TY - JOUR A1 - Steiner, Thomas A1 - Zachary, Marie A1 - Bauer, Susanne A1 - Müller, Martin J. A1 - Krischke, Markus A1 - Radziej, Sandra A1 - Klepsch, Maximilian A1 - Huettel, Bruno A1 - Eisenreich, Wolfgang A1 - Rudel, Thomas A1 - Beier, Dagmar T1 - Central Role of Sibling Small RNAs NgncR_162 and NgncR_163 in Main Metabolic Pathways of Neisseria gonorrhoeae JF - mBio N2 - Small bacterial regulatory RNAs (sRNAs) have been implicated in the regulation of numerous metabolic pathways. In most of these studies, sRNA-dependent regulation of mRNAs or proteins of enzymes in metabolic pathways has been predicted to affect the metabolism of these bacteria. However, only in a very few cases has the role in metabolism been demonstrated. Here, we performed a combined transcriptome and metabolome analysis to define the regulon of the sibling sRNAs NgncR_162 and NgncR_163 (NgncR_162/163) and their impact on the metabolism of Neisseria gonorrhoeae. These sRNAs have been reported to control genes of the citric acid and methylcitric acid cycles by posttranscriptional negative regulation. By transcriptome analysis, we now expand the NgncR_162/163 regulon by several new members and provide evidence that the sibling sRNAs act as both negative and positive regulators of target gene expression. Newly identified NgncR_162/163 targets are mostly involved in transport processes, especially in the uptake of glycine, phenylalanine, and branched-chain amino acids. NgncR_162/163 also play key roles in the control of serine-glycine metabolism and, hence, probably affect biosyntheses of nucleotides, vitamins, and other amino acids via the supply of one-carbon (C\(_1\)) units. Indeed, these roles were confirmed by metabolomics and metabolic flux analysis, which revealed a bipartite metabolic network with glucose degradation for the supply of anabolic pathways and the usage of amino acids via the citric acid cycle for energy metabolism. Thus, by combined deep RNA sequencing (RNA-seq) and metabolomics, we significantly extended the regulon of NgncR_162/163 and demonstrated the role of NgncR_162/163 in the regulation of central metabolic pathways of the gonococcus. KW - sRNA KW - Neisseria gonorrhoeae KW - posttranscriptional regulation KW - amino acid transporter KW - bipartite metabolism Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-313323 VL - 14 ER - TY - JOUR A1 - Değirmenci, Laura A1 - Rogé Ferreira, Fabio Luiz A1 - Vukosavljevic, Adrian A1 - Heindl, Cornelia A1 - Keller, Alexander A1 - Geiger, Dietmar A1 - Scheiner, Ricarda T1 - Sugar perception in honeybees JF - Frontiers in Physiology N2 - Honeybees (Apis mellifera) need their fine sense of taste to evaluate nectar and pollen sources. Gustatory receptors (Grs) translate taste signals into electrical responses. In vivo experiments have demonstrated collective responses of the whole Gr-set. We here disentangle the contributions of all three honeybee sugar receptors (AmGr1-3), combining CRISPR/Cas9 mediated genetic knock-out, electrophysiology and behaviour. We show an expanded sugar spectrum of the AmGr1 receptor. Mutants lacking AmGr1 have a reduced response to sucrose and glucose but not to fructose. AmGr2 solely acts as co-receptor of AmGr1 but not of AmGr3, as we show by electrophysiology and using bimolecular fluorescence complementation. Our results show for the first time that AmGr2 is indeed a functional receptor on its own. Intriguingly, AmGr2 mutants still display a wildtype-like sugar taste. AmGr3 is a specific fructose receptor and is not modulated by a co-receptor. Eliminating AmGr3 while preserving AmGr1 and AmGr2 abolishes the perception of fructose but not of sucrose. Our comprehensive study on the functions of AmGr1, AmGr2 and AmGr3 in honeybees is the first to combine investigations on sugar perception at the receptor level and simultaneously in vivo. We show that honeybees rely on two gustatory receptors to sense all relevant sugars. KW - AmGr1 KW - AmGr2 KW - AmGr3 KW - sugar responsiveness KW - proboscis extension response (PER) KW - gustatory receptors (Grs) KW - honeybee taste perception Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-302284 SN - 1664-042X VL - 13 ER - TY - JOUR A1 - Sexauer, Moritz A1 - Bhasin, Hemal A1 - Schön, Maria A1 - Roitsch, Elena A1 - Wall, Caroline A1 - Herzog, Ulrike A1 - Markmann, Katharina T1 - A micro RNA mediates shoot control of root branching JF - Nature Communications N2 - Plants extract mineral nutrients from the soil, or from interactions with mutualistic soil microbes via their root systems. Adapting root architecture to nutrient availability enables efficient resource utilization, particularly in patchy and dynamic environments. Root growth responses to soil nitrogen levels are shoot-mediated, but the identity of shoot-derived mobile signals regulating root growth responses has remained enigmatic. Here we show that a shoot-derived micro RNA, miR2111, systemically steers lateral root initiation and nitrogen responsiveness through its root target TML (TOO MUCH LOVE) in the legume Lotus japonicus, where miR2111 and TML were previously shown to regulate symbiotic infections with nitrogen fixing bacteria. Intriguingly, systemic control of lateral root initiation by miR2111 and TML/HOLT (HOMOLOGUE OF LEGUME TML) was conserved in the nonsymbiotic ruderal Arabidopsis thaliana, which follows a distinct ecological strategy. Thus, the miR2111-TML/HOLT regulon emerges as an essential, conserved factor in adaptive shoot control of root architecture in dicots. KW - evolutionary developmental biology KW - plant development KW - plant molecular biology KW - plant signalling Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-357472 VL - 14 ER - TY - JOUR A1 - Amatobi, Kelechi M. A1 - Ozbek-Unal, Ayten Gizem A1 - Schäbler, Stefan A1 - Deppisch, Peter A1 - Helfrich-Förster, Charlotte A1 - Mueller, Martin J. A1 - Wegener, Christian A1 - Fekete, Agnes T1 - The circadian clock is required for rhythmic lipid transport in Drosophila in interaction with diet and photic condition JF - Journal of Lipid Research N2 - Modern lifestyle is often at odds with endogenously driven rhythmicity, which can lead to circadian disruption and metabolic syndrome. One signature for circadian disruption is a reduced or altered metabolite cycling in the circulating tissue reflecting the current metabolic status. Drosophila is a well-established model in chronobiology, but day-time dependent variations of transport metabolites in the fly circulation are poorly characterized. Here, we sampled fly hemolymph throughout the day and analyzed diacylglycerols (DGs), phosphoethanolamines (PEs) and phosphocholines (PCs) using LC-MS. In wild-type flies kept on sugar-only medium under a light-dark cycle, all transport lipid species showed a synchronized bimodal oscillation pattern with maxima at the beginning and end of the light phase which were impaired in period01 clock mutants. In wild-type flies under constant dark conditions, the oscillation became monophasic with a maximum in the middle of the subjective day. In strong support of clock-driven oscillations, levels of the targeted lipids peaked once in the middle of the light phase under time-restricted feeding independent of the time of food intake. When wild-type flies were reared on full standard medium, the rhythmic alterations of hemolymph lipid levels were greatly attenuated. Our data suggest that the circadian clock aligns daily oscillations of DGs, PEs, and PCs in the hemolymph to the anabolic siesta phase, with a strong influence of light on phase and modality. KW - hemolymph lipids KW - lipidomics KW - circadian rhythm KW - feeding KW - locomotor activity KW - light-driven metabolism Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-349961 VL - 64 IS - 10 ER - TY - JOUR A1 - Lu, Jinping A1 - Dreyer, Ingo A1 - Dickinson, Miles Sasha A1 - Panzer, Sabine A1 - Jaślan, Dawid A1 - Navarro-Retamal, Carlos A1 - Geiger, Dietmar A1 - Terpitz, Ulrich A1 - Becker, Dirk A1 - Stroud, Robert M. A1 - Marten, Irene A1 - Hedrich, Rainer T1 - Vicia faba SV channel VfTPC1 is a hyperexcitable variant of plant vacuole two pore channels JF - eLife N2 - To fire action-potential-like electrical signals, the vacuole membrane requires the two-pore channel TPC1, formerly called SV channel. The TPC1/SV channel functions as a depolarization-stimulated, non-selective cation channel that is inhibited by luminal Ca\(^{2+}\). In our search for species-dependent functional TPC1 channel variants with different luminal Ca\(^{2+}\) sensitivity, we found in total three acidic residues present in Ca\(^{2+}\) sensor sites 2 and 3 of the Ca\(^{2+}\)-sensitive AtTPC1 channel from Arabidopsis thaliana that were neutral in its Vicia faba ortholog and also in those of many other Fabaceae. When expressed in the Arabidopsis AtTPC1-loss-of-function background, wild-type VfTPC1 was hypersensitive to vacuole depolarization and only weakly sensitive to blocking luminal Ca\(^{2+}\). When AtTPC1 was mutated for these VfTPC1-homologous polymorphic residues, two neutral substitutions in Ca\(^{2+}\) sensor site 3 alone were already sufficient for the Arabidopsis At-VfTPC1 channel mutant to gain VfTPC1-like voltage and luminal Ca\(^{2+}\) sensitivity that together rendered vacuoles hyperexcitable. Thus, natural TPC1 channel variants exist in plant families which may fine-tune vacuole excitability and adapt it to environmental settings of the particular ecological niche. KW - A. thaliana KW - Brassicaceae KW - Fabaceae KW - pore KW - potassium channel KW - voltage gating KW - vacuolar calcium sensor Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-350264 VL - 12 ER - TY - JOUR A1 - Thomas, Sarah A1 - Fiebig, Juliane E. A1 - Kuhn, Eva-Maria A1 - Mayer, Dominik S. A1 - Filbeck, Sebastian A1 - Schmitz, Werner A1 - Krischke, Markus A1 - Gropp, Roswitha A1 - Mueller, Thomas D. T1 - Design of glycoengineered IL-4 antagonists employing chemical and biosynthetic glycosylation JF - ACS Omega N2 - Interleukin-4 (IL-4) plays a key role in atopic diseases. It coordinates T-helper cell differentiation to subtype 2, thereby directing defense toward humoral immunity. Together with Interleukin-13, IL-4 further induces immunoglobulin class switch to IgE. Antibodies of this type activate mast cells and basophilic and eosinophilic granulocytes, which release pro-inflammatory mediators accounting for the typical symptoms of atopic diseases. IL-4 and IL-13 are thus major targets for pharmaceutical intervention strategies to treat atopic diseases. Besides neutralizing antibodies against IL-4, IL-13, or its receptors, IL-4 antagonists can present valuable alternatives. Pitrakinra, an Escherichia coli-derived IL-4 antagonist, has been evaluated in clinical trials for asthma treatment in the past; however, deficits such as short serum lifetime and potential immunogenicity among others stopped further development. To overcome such deficits, PEGylation of therapeutically important proteins has been used to increase the lifetime and proteolytic stability. As an alternative, glycoengineering is an emerging strategy used to improve pharmacokinetics of protein therapeutics. In this study, we have established different strategies to attach glycan moieties to defined positions in IL-4. Different chemical attachment strategies employing thiol chemistry were used to attach a glucose molecule at amino acid position 121, thereby converting IL-4 into a highly effective antagonist. To enhance the proteolytic stability of this IL-4 antagonist, additional glycan structures were introduced by glycoengineering utilizing eucaryotic expression. IL-4 antagonists with a combination of chemical and biosynthetic glycoengineering could be useful as therapeutic alternatives to IL-4 neutralizing antibodies already used to treat atopic diseases. KW - Interleukin-4 (IL-4) KW - atopic diseases KW - IL-4 antagonists KW - glycoengineering KW - biosynthetic glycosylation KW - chemical glycosylation Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-350278 SN - 2470-1343 VL - 8 IS - 28 ER - TY - JOUR A1 - Faist, Hanna A1 - Ankenbrand, Markus J. A1 - Sickel, Wiebke A1 - Hentschel, Ute A1 - Keller, Alexander A1 - Deeken, Rosalia T1 - Opportunistic bacteria of grapevine crown galls are equipped with the genomic repertoire for opine utilization JF - Genome Biology and Evolution N2 - Young grapevines (Vitis vinifera) suffer and eventually can die from the crown gall disease caused by the plant pathogen Allorhizobium vitis (Rhizobiaceae). Virulent members of A. vitis harbor a tumor-inducing plasmid and induce formation of crown galls due to the oncogenes encoded on the transfer DNA. The expression of oncogenes in transformed host cells induces unregulated cell proliferation and metabolic and physiological changes. The crown gall produces opines uncommon to plants, which provide an important nutrient source for A. vitis harboring opine catabolism enzymes. Crown galls host a distinct bacterial community, and the mechanisms establishing a crown gall–specific bacterial community are currently unknown. Thus, we were interested in whether genes homologous to those of the tumor-inducing plasmid coexist in the genomes of the microbial species coexisting in crown galls. We isolated 8 bacterial strains from grapevine crown galls, sequenced their genomes, and tested their virulence and opine utilization ability in bioassays. In addition, the 8 genome sequences were compared with 34 published bacterial genomes, including closely related plant-associated bacteria not from crown galls. Homologous genes for virulence and opine anabolism were only present in the virulent Rhizobiaceae. In contrast, homologs of the opine catabolism genes were present in all strains including the nonvirulent members of the Rhizobiaceae and non-Rhizobiaceae. Gene neighborhood and sequence identity of the opine degradation cluster of virulent and nonvirulent strains together with the results of the opine utilization assay support the important role of opine utilization for cocolonization in crown galls, thereby shaping the crown gall community. KW - Vitis vinifera KW - bacterial community KW - Agrobacterium KW - Allorhizobium vitis KW - Ti plasmids KW - de novo sequenced genomes Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-350172 VL - 15 IS - 12 ER - TY - JOUR A1 - Lübbe, Torben A1 - Lamarque, Laurent J. A1 - Delzon, Sylvain A1 - Torres Ruiz, José M. A1 - Burlett, Régis A1 - Leuschner, Christoph A1 - Schuldt, Bernhard T1 - High variation in hydraulic efficiency but not xylem safety between roots and branches in four temperate broad–leaved tree species JF - Functional Ecology N2 - Xylem hydraulic safety and efficiency are key traits determining tree fitness in a warmer and drier world. While numerous plant hydraulic studies have focused on branches, our understanding of root hydraulic functioning remains limited, although roots control water uptake, influence stomatal regulation and have commonly been considered as the most vulnerable organ along the hydraulic pathway. We investigated 11 traits related to xylem safety and efficiency along the hydraulic pathway in four temperate broad-leaved tree species. Continuous vessel tapering from coarse roots to stems and branches caused considerable reduction in hydraulic efficiency. Wood density was always lowest in roots, but did not decline linearly along the flow path. In contrast, xylem embolism resistance (P50) did not differ significantly between roots and branches, except for one species. The limited variation in xylem safety between organs did not adequately reflect the corresponding reductions in vessel diameter (by ~70%) and hydraulic efficiency (by ~85%). Although we did not observe any trade-off between xylem safety and specific conductivity, vessel diameter, vessel lumen fraction and wood density were related to embolism resistance, both across and partly within organs. We conclude that coarse roots are not highly vulnerable to xylem embolism as commonly believed, indicating that hydraulic failure during soil drying might be restricted to fine roots. KW - embolism resistance KW - wood density KW - wood anatomy KW - vulnerability curve KW - vessel tapering KW - flow path KW - hydraulic architecture KW - hydraulic conductivity Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-318587 SN - 0269-8463 VL - 36 IS - 3 SP - 699 EP - 712 ER - TY - JOUR A1 - Schilcher, Felix A1 - Hilsmann, Lioba A1 - Ankenbrand, Markus J. A1 - Krischke, Markus A1 - Mueller, Martin J. A1 - Steffan-Dewenter, Ingolf A1 - Scheiner, Ricarda T1 - Honeybees are buffered against undernourishment during larval stages JF - Frontiers in Insect Science N2 - The negative impact of juvenile undernourishment on adult behavior has been well reported for vertebrates, but relatively little is known about invertebrates. In honeybees, nutrition has long been known to affect task performance and timing of behavioral transitions. Whether and how a dietary restriction during larval development affects the task performance of adult honeybees is largely unknown. We raised honeybees in-vitro, varying the amount of a standardized diet (150 µl, 160 µl, 180 µl in total). Emerging adults were marked and inserted into established colonies. Behavioral performance of nurse bees and foragers was investigated and physiological factors known to be involved in the regulation of social organization were quantified. Surprisingly, adult honeybees raised under different feeding regimes did not differ in any of the behaviors observed. No differences were observed in physiological parameters apart from weight. Honeybees were lighter when undernourished (150 µl), while they were heavier under the overfed treatment (180 µl) compared to the control group raised under a normal diet (160 µl). These data suggest that dietary restrictions during larval development do not affect task performance or physiology in this social insect despite producing clear effects on adult weight. We speculate that possible effects of larval undernourishment might be compensated during the early period of adult life. KW - nutrition KW - juvenile hormone KW - nurse bees KW - foragers KW - triglycerides KW - undernourishment KW - task allocation Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-304646 SN - 2673-8600 VL - 2 ER - TY - JOUR A1 - Scherzer, Sönke A1 - Huang, Shouguang A1 - Iosip, Anda A1 - Kreuzer, Ines A1 - Yokawa, Ken A1 - Al-Rasheid, Khaled A. S. A1 - Heckmann, Manfred A1 - Hedrich, Rainer T1 - Ether anesthetics prevents touch-induced trigger hair calcium-electrical signals excite the Venus flytrap JF - Scientific reports N2 - Plants do not have neurons but operate transmembrane ion channels and can get electrical excited by physical and chemical clues. Among them the Venus flytrap is characterized by its peculiar hapto-electric signaling. When insects collide with trigger hairs emerging the trap inner surface, the mechanical stimulus within the mechanosensory organ is translated into a calcium signal and an action potential (AP). Here we asked how the Ca\(^{2+}\) wave and AP is initiated in the trigger hair and how it is feed into systemic trap calcium-electrical networks. When Dionaea muscipula trigger hairs matures and develop hapto-electric excitability the mechanosensitive anion channel DmMSL10/FLYC1 and voltage dependent SKOR type Shaker K\(^{+}\) channel are expressed in the sheering stress sensitive podium. The podium of the trigger hair is interface to the flytrap’s prey capture and processing networks. In the excitable state touch stimulation of the trigger hair evokes a rise in the podium Ca2+ first and before the calcium signal together with an action potential travel all over the trap surface. In search for podium ion channels and pumps mediating touch induced Ca\(^{2+}\) transients, we, in mature trigger hairs firing fast Ca\(^{2+}\) signals and APs, found OSCA1.7 and GLR3.6 type Ca\(^{2+}\) channels and ACA2/10 Ca\(^{2+}\) pumps specifically expressed in the podium. Like trigger hair stimulation, glutamate application to the trap directly evoked a propagating Ca\(^{2+}\) and electrical event. Given that anesthetics affect K\(^+\) channels and glutamate receptors in the animal system we exposed flytraps to an ether atmosphere. As result propagation of touch and glutamate induced Ca\(^{2+}\) and AP long-distance signaling got suppressed, while the trap completely recovered excitability when ether was replaced by fresh air. In line with ether targeting a calcium channel addressing a Ca\(^{2+}\) activated anion channel the AP amplitude declined before the electrical signal ceased completely. Ether in the mechanosensory organ did neither prevent the touch induction of a calcium signal nor this post stimulus decay. This finding indicates that ether prevents the touch activated, glr3.6 expressing base of the trigger hair to excite the capture organ. KW - biophysics KW - drug discovery KW - physiology KW - plan sciences Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-300411 VL - 12 ER - TY - JOUR A1 - Kumar, Manish A1 - Waite, Pierre-André A1 - Paligi, Sharath Shyamappa A1 - Schuldt, Bernhard T1 - Influence of juvenile growth on xylem safety and efficiency in three temperate tree species JF - Forests N2 - The evolution of the internal water transport system was a prerequisite for high plant productivity. In times of climate change, understanding the dependency of juvenile growth on xylem hydraulic physiology is therefore of high importance. Here, we explored various wood anatomical, hydraulic, and leaf morphological traits related to hydraulic safety and efficiency in three temperate broadleaved tree species (Acer pseudoplatanus, Betula pendula, and Sorbus aucuparia). We took advantage of a severe natural heat wave that resulted in different climatic growing conditions for even-aged plants from the same seed source growing inside a greenhouse and outside. Inside the greenhouse, the daily maximum vapour pressure deficit was on average 36% higher than outside during the growing seasons. Because of the higher atmospheric moisture stress, the biomass production differed up to 5.6-fold between both groups. Except for one species, a high productivity was associated with a high hydraulic efficiency caused by large xylem vessels and a large, supported leaf area. Although no safety-efficiency trade-off was observed, productivity was significantly related to P\(_{50}\) in two of the tree species but without revealing any clear pattern. A considerable plasticity in given traits was observed between both groups, with safety-related traits being more static while efficiency-related traits revealed a higher intra-specific plasticity. This was associated with other wood anatomical and leaf morphological adjustments. We confirm that a high hydraulic efficiency seems to be a prerequisite for a high biomass production, while our controversial results on the growth–xylem safety relationship confirm that safety-efficiency traits are decoupled and that their relationship with juvenile growth and water regime is species-specific. KW - hydraulic efficiency KW - biomass KW - growth rate KW - hydraulic variability KW - phenotypic plasticity KW - safety-efficiency trade-off KW - vulnerability curve Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-278889 SN - 1999-4907 VL - 13 IS - 6 ER - TY - JOUR A1 - de Souza, Aline Xavier A1 - Riederer, Markus A1 - Leide, Jana T1 - Multifunctional contribution of the inflated fruiting calyx: implication for cuticular barrier profiles of the solanaceous genera Physalis, Alkekengi, and Nicandra JF - Frontiers in Plant Science N2 - Pivotal barrier properties of the hydrophobic plant cuticle covering aerial plant surfaces depend on its physicochemical composition. Among plant species and organs, compounds of this boundary layer between the plant interior and the environment vary considerably but cuticle-related studies comparing different organs from the same plant species are still scarce. Thus, this study focused on the cuticle profiles of Physalis peruviana, Physalis ixocarpa, Alkekengi officinarum, and Nicandra physalodes species. Inflated fruiting calyces enveloping fruits make Physalis, Alkekengi, and Nicandra highly recognizable genera among the Solanoideae subfamily. Although the inflation of fruiting calyces is well discussed in the literature still little is known about their post-floral functionalities. Cuticular composition, surface structure, and barrier function were examined and compared in fully expanded amphistomatous leaves, ripe astomatous fruits, and fully inflated hypostomatous fruiting calyces. Species- and organ-specific abundances of non-glandular and glandular trichomes revealed high structural diversity, covering not only abaxial and adaxial leaf surfaces but also fruiting calyx surfaces, whereas fruits were glabrous. Cuticular waxes, which limit non-stomatal transpiration, ranged from <1 μg cm\(^{−2}\) on P. peruviana fruiting calyces and N. physalodes fruits to 22 μg cm\(^{−2}\) on P. peruviana fruits. Very-long-chain aliphatic compounds, notably n-alkanes, iso-, and anteiso-branched alkanes, alkanols, alkanoic acids, and alkyl esters, dominated the cuticular wax coverages (≥86%). Diversity of cuticular wax patterns rose from leaves to fruiting calyces and peaked in fruits. The polymeric cutin matrix providing the structural framework for cuticular waxes was determined to range from 81 μg cm\(^{−2}\) for N. physalodes to 571 μg cm\(^{−2}\) for A. officinarum fruits. Cuticular transpiration barriers were highly efficient, with water permeabilities being ≤5 × 10\(^{−5}\) m s\(^{−1}\). Only the cuticular water permeability of N. physalodes fruits was 10 × 10\(^{−5}\) m s\(^{−1}\) leading to their early desiccation and fruits that easily split, whereas P. peruviana, P. ixocarpa, and A. officinarum bore fleshy fruits for extended periods after maturation. Regarding the functional significance, fruiting calyces establish a physicochemical shield that reduces water loss and enables fruit maturation within a protective microclimate, and promotes different seed dispersal strategies among plant species investigated. KW - inflated fruiting calyx KW - leaf KW - fruit KW - plant cuticle KW - wax composition KW - Physalis KW - Alkekengi KW - Nicandra Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-280251 SN - 1664-462X VL - 13 ER - TY - JOUR A1 - Lambour, Benjamin A1 - Glenz, René A1 - Forner, Carmen A1 - Krischke, Markus A1 - Mueller, Martin J. A1 - Fekete, Agnes A1 - Waller, Frank T1 - Sphingolipid long-chain base phosphate degradation can be a rate-limiting step in long-chain base homeostasis JF - Frontiers in Plant Science N2 - Sphingolipid long-chain bases (LCBs) are building blocks for membrane-localized sphingolipids, and are involved in signal transduction pathways in plants. Elevated LCB levels are associated with the induction of programmed cell death and pathogen-derived toxin-induced cell death. Therefore, levels of free LCBs can determine survival of plant cells. To elucidate the contribution of metabolic pathways regulating high LCB levels, we applied the deuterium-labeled LCB D-erythro-sphinganine-d7 (D7-d18:0), the first LCB in sphingolipid biosynthesis, to Arabidopsis leaves and quantified labeled LCBs, LCB phosphates (LCB-Ps), and 14 abundant ceramide (Cer) species over time. We show that LCB D7-d18:0 is rapidly converted into the LCBs d18:0P, t18:0, and t18:0P. Deuterium-labeled ceramides were less abundant, but increased over time, with the highest levels detected for Cer(d18:0/16:0), Cer(d18:0/24:0), Cer(t18:0/16:0), and Cer(t18:0/22:0). A more than 50-fold increase of LCB-P levels after leaf incubation in LCB D7-d18:0 indicated that degradation of LCBs via LCB-Ps is important, and we hypothesized that LCB-P degradation could be a rate-limiting step to reduce high levels of LCBs. To functionally test this hypothesis, we constructed a transgenic line with dihydrosphingosine-1-phosphate lyase 1 (DPL1) under control of an inducible promotor. Higher expression of DPL1 significantly reduced elevated LCB-P and LCB levels induced by Fumonisin B1, and rendered plants more resistant against this fungal toxin. Taken together, we provide quantitative data on the contribution of major enzymatic pathways to reduce high LCB levels, which can trigger cell death. Specifically, we provide functional evidence that DPL1 can be a rate-limiting step in regulating high LCB levels. KW - sphingolipid KW - long-chain base KW - plant sphingolipid metabolism KW - cell death KW - metabolic flux analysis KW - dihydrosphingosine-1-phosphate lyase KW - LC–MS/MS Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-277679 SN - 1664-462X VL - 13 ER - TY - JOUR A1 - Siverino, Claudia A1 - Fahmy-Garcia, Shorouk A1 - Mumcuoglu, Didem A1 - Oberwinkler, Heike A1 - Muehlemann, Markus A1 - Mueller, Thomas A1 - Farrell, Eric A1 - van Osch, Gerjo J. V. M. A1 - Nickel, Joachim T1 - Site-directed immobilization of an engineered bone morphogenetic protein 2 (BMP2) variant to collagen-based microspheres induces bone formation in vivo JF - International Journal of Molecular Sciences N2 - For the treatment of large bone defects, the commonly used technique of autologous bone grafting presents several drawbacks and limitations. With the discovery of the bone-inducing capabilities of bone morphogenetic protein 2 (BMP2), several delivery techniques were developed and translated to clinical applications. Implantation of scaffolds containing adsorbed BMP2 showed promising results. However, off-label use of this protein-scaffold combination caused severe complications due to an uncontrolled release of the growth factor, which has to be applied in supraphysiological doses in order to induce bone formation. Here, we propose an alternative strategy that focuses on the covalent immobilization of an engineered BMP2 variant to biocompatible scaffolds. The new BMP2 variant harbors an artificial amino acid with a specific functional group, allowing a site-directed covalent scaffold functionalization. The introduced artificial amino acid does not alter BMP2′s bioactivity in vitro. When applied in vivo, the covalently coupled BMP2 variant induces the formation of bone tissue characterized by a structurally different morphology compared to that induced by the same scaffold containing ab-/adsorbed wild-type BMP2. Our results clearly show that this innovative technique comprises translational potential for the development of novel osteoinductive materials, improving safety for patients and reducing costs. KW - bone morphogenetic protein 2 (BMP2) KW - bone regeneration KW - covalent coupling KW - subcutaneous animal model Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-284572 SN - 1422-0067 VL - 23 IS - 7 ER - TY - JOUR A1 - Weithmann, Greta A1 - Link, Roman M. A1 - Banzragch, Bat-Enerel A1 - Würzberg, Laura A1 - Leuschner, Christoph A1 - Schuldt, Bernhard T1 - Soil water availability and branch age explain variability in xylem safety of European beech in Central Europe JF - Oecologia N2 - Xylem embolism resistance has been identified as a key trait with a causal relation to drought-induced tree mortality, but not much is known about its intra-specific trait variability (ITV) in dependence on environmental variation. We measured xylem safety and efficiency in 300 European beech (Fagus sylvatica L.) trees across 30 sites in Central Europe, covering a precipitation reduction from 886 to 522 mm year−1. A broad range of variables that might affect embolism resistance in mature trees, including climatic and soil water availability, competition, and branch age, were examined. The average P50 value varied by up to 1 MPa between sites. Neither climatic aridity nor structural variables had a significant influence on P50. However, P50 was less negative for trees with a higher soil water storage capacity, and positively related to branch age, while specific conductivity (Ks) was not significantly associated with either of these variables. The greatest part of the ITV for xylem safety and efficiency was attributed to random variability within populations. We conclude that the influence of site water availability on P50 and Ks is low in European beech, and that the high degree of within-population variability for P50, partly due to variation in branch age, hampers the identification of a clear environmental signal. KW - Bodenwasser KW - Buche KW - Mitteleuropa KW - Xylem KW - Available soil water capacity KW - Climatic water balance KW - Embolism resistance KW - Hegyi competition index KW - Hydraulic conductivity KW - Hydraulic plasticity KW - Precipitation gradient KW - Xylem vulnerability curve Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-324228 VL - 198 IS - 3 ER - TY - JOUR A1 - Karimi, Sohail M. A1 - Freund, Matthias A1 - Wager, Brittney M. A1 - Knoblauch, Michael A1 - Fromm, Jörg A1 - M. Mueller, Heike A1 - Ache, Peter A1 - Krischke, Markus A1 - Mueller, Martin J. A1 - Müller, Tobias A1 - Dittrich, Marcus A1 - Geilfus, Christoph-Martin A1 - Alfaran, Ahmed H. A1 - Hedrich, Rainer A1 - Deeken, Rosalia T1 - Under salt stress guard cells rewire ion transport and abscisic acid signaling JF - New Phytologist N2 - Soil salinity is an increasingly global problem which hampers plant growth and crop yield. Plant productivity depends on optimal water-use efficiency and photosynthetic capacity balanced by stomatal conductance. Whether and how stomatal behavior contributes to salt sensitivity or tolerance is currently unknown. This work identifies guard cell-specific signaling networks exerted by a salt-sensitive and salt-tolerant plant under ionic and osmotic stress conditions accompanied by increasing NaCl loads. We challenged soil-grown Arabidopsis thaliana and Thellungiella salsuginea plants with short- and long-term salinity stress and monitored genome-wide gene expression and signals of guard cells that determine their function. Arabidopsis plants suffered from both salt regimes and showed reduced stomatal conductance while Thellungiella displayed no obvious stress symptoms. The salt-dependent gene expression changes of guard cells supported the ability of the halophyte to maintain high potassium to sodium ratios and to attenuate the abscisic acid (ABA) signaling pathway which the glycophyte kept activated despite fading ABA concentrations. Our study shows that salinity stress and even the different tolerances are manifested on a single cell level. Halophytic guard cells are less sensitive than glycophytic guard cells, providing opportunities to manipulate stomatal behavior and improve plant productivity. KW - soil KW - stomata KW - abscisic acid (ABA) KW - glycophyte Arabidopsis KW - guard cell KW - halophyte Thellungiella/Eutrema KW - ion transport KW - salt stress Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-259635 VL - 231 IS - 3 ER - TY - JOUR A1 - Schilcher, Felix A1 - Hilsmann, Lioba A1 - Rauscher, Lisa A1 - Değirmenci, Laura A1 - Krischke, Markus A1 - Krischke, Beate A1 - Ankenbrand, Markus A1 - Rutschmann, Benjamin A1 - Mueller, Martin J. A1 - Steffan-Dewenter, Ingolf A1 - Scheiner, Ricarda T1 - In vitro rearing changes social task performance and physiology in honeybees JF - Insects N2 - In vitro rearing of honeybee larvae is an established method that enables exact control and monitoring of developmental factors and allows controlled application of pesticides or pathogens. However, only a few studies have investigated how the rearing method itself affects the behavior of the resulting adult honeybees. We raised honeybees in vitro according to a standardized protocol: marking the emerging honeybees individually and inserting them into established colonies. Subsequently, we investigated the behavioral performance of nurse bees and foragers and quantified the physiological factors underlying the social organization. Adult honeybees raised in vitro differed from naturally reared honeybees in their probability of performing social tasks. Further, in vitro-reared bees foraged for a shorter duration in their life and performed fewer foraging trips. Nursing behavior appeared to be unaffected by rearing condition. Weight was also unaffected by rearing condition. Interestingly, juvenile hormone titers, which normally increase strongly around the time when a honeybee becomes a forager, were significantly lower in three- and four-week-old in vitro bees. The effects of the rearing environment on individual sucrose responsiveness and lipid levels were rather minor. These data suggest that larval rearing conditions can affect the task performance and physiology of adult bees despite equal weight, pointing to an important role of the colony environment for these factors. Our observations of behavior and metabolic pathways offer important novel insight into how the rearing environment affects adult honeybees. KW - honeybee KW - artificial rearing KW - behavior KW - in vitro KW - juvenile hormone KW - triglycerides KW - PER KW - foraging KW - nursing Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-252305 SN - 2075-4450 VL - 13 IS - 1 ER - TY - JOUR A1 - Röll, Alexander A1 - Ramesha, Mundre N. A1 - Link, Roman M. A1 - Hertel, Dietrich A1 - Schuldt, Bernhard A1 - Patil, Shekhargouda L. A1 - Hölscher, Dirk T1 - Water availability controls the biomass increment of Melia dubia in South India JF - Forests N2 - Farmland tree cultivation is considered an important option for enhancing wood production. In South India, the native leaf-deciduous tree species Melia dubia is popular for short-rotation plantations. Across a rainfall gradient from 420 to 2170 mm year\(^{–1}\), we studied 186 farmland woodlots between one and nine years in age. The objectives were to identify the main factors controlling aboveground biomass (AGB) and growth rates. A power-law growth model predicts an average stand-level AGB of 93.8 Mg ha\(^{–1}\) for nine-year-old woodlots. The resulting average annual AGB increment over the length of the rotation cycle is 10.4 Mg ha\(^{–1}\) year\(^{–1}\), which falls within the range reported for other tropical tree plantations. When expressing the parameters of the growth model as functions of management, climate and soil variables, it explains 65% of the variance in AGB. The results indicate that water availability is the main driver of the growth of M. dubia. Compared to the effects of water availability, the effects of soil nutrients are 26% to 60% smaller. We conclude that because of its high biomass accumulation rates in farm forestry, M. dubia is a promising candidate for short-rotation plantations in South India and beyond. KW - aboveground biomass KW - climatological water deficit KW - farm forestry KW - farmland woodlots KW - rainfall gradient KW - soil KW - wood production Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-250150 SN - 1999-4907 VL - 12 IS - 12 ER - TY - JOUR A1 - Tang, Ruijing A1 - Yang, Shang A1 - Nagel, Georg A1 - Gao, Shiqiang T1 - mem-iLID, a fast and economic protein purification method JF - Bioscience Reports N2 - Protein purification is the vital basis to study the function, structure and interaction of proteins. Widely used methods are affinity chromatography-based purifications, which require different chromatography columns and harsh conditions, such as acidic pH and/or adding imidazole or high salt concentration, to elute and collect the purified proteins. Here we established an easy and fast purification method for soluble proteins under mild conditions, based on the light-induced protein dimerization system improved light-induced dimer (iLID), which regulates protein binding and release with light. We utilize the biological membrane, which can be easily separated by centrifugation, as the port to anchor the target proteins. In Xenopus laevis oocyte and Escherichia coli, the blue light-sensitive part of iLID, AsLOV2-SsrA, was targeted to the plasma membrane by different membrane anchors. The other part of iLID, SspB, was fused with the protein of interest (POI) and expressed in the cytosol. The SspB-POI can be captured to the membrane fraction through light-induced binding to AsLOV2-SsrA and then released purely to fresh buffer in the dark after simple centrifugation and washing. This method, named mem-iLID, is very flexible in scale and economic. We demonstrate the quickly obtained yield of two pure and fully functional enzymes: a DNA polymerase and a light-activated adenylyl cyclase. Furthermore, we also designed a new SspB mutant for better dissociation and less interference with the POI, which could potentially facilitate other optogenetic manipulations of protein–protein interaction. KW - light-induced dimerization KW - membrane anchor KW - Optogenetics KW - protein purification Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-261420 VL - 41 IS - 7 ER - TY - JOUR A1 - Zhou, Yang A1 - Ding, Meiqi A1 - Duan, Xiaodong A1 - Konrad, Kai R. A1 - Nagel, Georg A1 - Gao, Shiqiang T1 - Extending the Anion Channelrhodopsin-Based Toolbox for Plant Optogenetics JF - Membranes N2 - Optogenetics was developed in the field of neuroscience and is most commonly using light-sensitive rhodopsins to control the neural activities. Lately, we have expanded this technique into plant science by co-expression of a chloroplast-targeted β-carotene dioxygenase and an improved anion channelrhodopsin GtACR1 from the green alga Guillardia theta. The growth of Nicotiana tabacum pollen tube can then be manipulated by localized green light illumination. To extend the application of analogous optogenetic tools in the pollen tube system, we engineered another two ACRs, GtACR2, and ZipACR, which have different action spectra, light sensitivity and kinetic features, and characterized them in Xenopus laevis oocytes, Nicotiana benthamiana leaves and N. tabacum pollen tubes. We found that the similar molecular engineering method used to improve GtACR1 also enhanced GtACR2 and ZipACR performance in Xenopus laevis oocytes. The ZipACR1 performed in N. benthamiana mesophyll cells and N. tabacum pollen tubes with faster kinetics and reduced light sensitivity, allowing for optogenetic control of anion fluxes with better temporal resolution. The reduced light sensitivity would potentially facilitate future application in plants, grown under low ambient white light, combined with an optogenetic manipulation triggered by stronger green light. KW - optogenetics KW - rhodopsin KW - light-sensitive anion channel KW - surface potential recording KW - pollen tube Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-236617 SN - 2077-0375 VL - 11 IS - 4 ER - TY - JOUR A1 - Tian, Yuehui A1 - Nagel, Georg A1 - Gao, Shiqiang T1 - An engineered membrane-bound guanylyl cyclase with light-switchable activity JF - BMC Biology N2 - Background Microbial rhodopsins vary in their chemical properties, from light sensitive ion transport to different enzymatic activities. Recently, a novel family of two-component Cyclase (rhod)opsins (2c-Cyclop) from the green algae Chlamydomonas reinhardtii and Volvox carteri was characterized, revealing a light-inhibited guanylyl cyclase (GC) activity. More genes similar to 2c-Cyclop exist in algal genomes, but their molecular and physiological functions remained uncharacterized. Results Chlamyopsin-5 (Cop5) from C. reinhardtii is related to Cr2c-Cyclop1 (Cop6) and can be expressed in Xenopus laevis oocytes, but shows no GC activity. Here, we exchanged parts of Cop5 with the corresponding ones of Cr2c-Cyclop1. When exchanging the opsin part of Cr2c-Cyclop1 with that of Cop5, we obtained a bi-stable guanylyl cyclase (switch-Cyclop1) whose activity can be switched by short light flashes. The GC activity of switch-Cyclop1 is increased for hours by a short 380 nm illumination and switched off (20-fold decreased) by blue or green light. switch-Cyclop1 is very light-sensitive and can half-maximally be activated by ~ 150 photons/nm2 of 380 nm (~ 73 J/m2) or inhibited by ~ 40 photons/nm\(^2\) of 473 nm (~ 18 J/m\(^2\)). Conclusions This engineered guanylyl cyclase is the first light-switchable enzyme for cGMP level regulation. Light-regulated cGMP production with high light-sensitivity is a promising technique for the non-invasive investigation of the effects of cGMP signaling in many different tissues. KW - Chlamydomonas reinhardtii KW - cyclic GMP KW - guanylyl cyclase KW - optogenetics KW - rhodopsin Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-259181 VL - 19 IS - 1 ER - TY - JOUR A1 - Li, Kunkun A1 - Prada, Juan A1 - Damineli, Daniel S. C. A1 - Liese, Anja A1 - Romeis, Tina A1 - Dandekar, Thomas A1 - Feijó, José A. A1 - Hedrich, Rainer A1 - Konrad, Kai Robert T1 - An optimized genetically encoded dual reporter for simultaneous ratio imaging of Ca\(^{2+}\) and H\(^{+}\) reveals new insights into ion signaling in plants JF - New Phytologist N2 - Whereas the role of calcium ions (Ca\(^{2+}\)) in plant signaling is well studied, the physiological significance of pH‐changes remains largely undefined. Here we developed CapHensor, an optimized dual‐reporter for simultaneous Ca\(^{2+}\) and pH ratio‐imaging and studied signaling events in pollen tubes (PTs), guard cells (GCs), and mesophyll cells (MCs). Monitoring spatio‐temporal relationships between membrane voltage, Ca\(^{2+}\)‐ and pH‐dynamics revealed interconnections previously not described. In tobacco PTs, we demonstrated Ca\(^{2+}\)‐dynamics lag behind pH‐dynamics during oscillatory growth, and pH correlates more with growth than Ca\(^{2+}\). In GCs, we demonstrated abscisic acid (ABA) to initiate stomatal closure via rapid cytosolic alkalization followed by Ca2+ elevation. Preventing the alkalization blocked GC ABA‐responses and even opened stomata in the presence of ABA, disclosing an important pH‐dependent GC signaling node. In MCs, a flg22‐induced membrane depolarization preceded Ca2+‐increases and cytosolic acidification by c. 2 min, suggesting a Ca\(^{2+}\)/pH‐independent early pathogen signaling step. Imaging Ca2+ and pH resolved similar cytosol and nuclear signals and demonstrated flg22, but not ABA and hydrogen peroxide to initiate rapid membrane voltage‐, Ca\(^{2+}\)‐ and pH‐responses. We propose close interrelation in Ca\(^{2+}\)‐ and pH‐signaling that is cell type‐ and stimulus‐specific and the pH having crucial roles in regulating PT growth and stomata movement. KW - abscisic acid (ABA) KW - calcium KW - flg22 KW - guard cells KW - imaging KW - ion signaling KW - pH KW - pollen tube Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-239847 VL - 230 IS - 6 SP - 2292 EP - 2310 ER - TY - JOUR A1 - Nuhkat, Maris A1 - Brosché, Mikael A1 - Stoezle-Feix, Sonja A1 - Dietrich, Petra A1 - Hedrich, Rainer A1 - Roelfsema, M. Rob G. A1 - Kollist, Hannes T1 - Rapid depolarization and cytosolic calcium increase go hand-in-hand in mesophyll cells' ozone response JF - New Phytologist N2 - Plant stress signalling involves bursts of reactive oxygen species (ROS), which can be mimicked by the application of acute pulses of ozone. Such ozone-pulses inhibit photosynthesis and trigger stomatal closure in a few minutes, but the signalling that underlies these responses remains largely unknown. We measured changes in Arabidopsis thaliana gas exchange after treatment with acute pulses of ozone and set up a system for simultaneous measurement of membrane potential and cytosolic calcium with the fluorescent reporter R-GECO1. We show that within 1 min, prior to stomatal closure, O\(_{3}\) triggered a drop in whole-plant CO\(_{2}\) uptake. Within this early phase, O\(_{3}\) pulses (200–1000 ppb) elicited simultaneous membrane depolarization and cytosolic calcium increase, whereas these pulses had no long-term effect on either stomatal conductance or photosynthesis. In contrast, pulses of 5000 ppb O\(_{3}\) induced cell death, systemic Ca\(^{2+}\) signals and an irreversible drop in stomatal conductance and photosynthetic capacity. We conclude that mesophyll cells respond to ozone in a few seconds by distinct pattern of plasma membrane depolarizations accompanied by an increase in the cytosolic calcium ion (Ca\(^{2+}\)) level. These responses became systemic only at very high ozone concentrations. Thus, plants have rapid mechanism to sense and discriminate the strength of ozone signals. KW - reactive oxygen species (ROS) KW - Arabidopsis thaliana KW - Ca\(^{2+}\) indicator KW - Ca\(^{2+}\) signalling KW - membrane depolarization KW - mesophyll KW - ozone Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-259646 VL - 232 IS - 4 ER - TY - JOUR A1 - Dindas, Julian A1 - Dreyer, Ingo A1 - Huang, Shouguang A1 - Hedrich, Rainer A1 - Roelfsema, M. Rob G. T1 - A voltage-dependent Ca\(^{2+}\) homeostat operates in the plant vacuolar membrane JF - New Phytologist N2 - Cytosolic calcium signals are evoked by a large variety of biotic and abiotic stimuli and play an important role in cellular and long distance signalling in plants. While the function of the plasma membrane in cytosolic Ca\(^{2+}\) signalling has been intensively studied, the role of the vacuolar membrane remains elusive. A newly developed vacuolar voltage clamp technique was used in combination with live-cell imaging, to study the role of the vacuolar membrane in Ca\(^{2+}\) and pH homeostasis of bulging root hair cells of Arabidopsis. Depolarisation of the vacuolar membrane caused a rapid increase in the Ca\(^{2+}\) concentration and alkalised the cytosol, while hyperpolarisation led to the opposite responses. The relationship between the vacuolar membrane potential, the cytosolic pH and Ca2+ concentration suggests that a vacuolar H\(^{+}\)/Ca\(^{2+}\) exchange mechanism plays a central role in cytosolic Ca2+ homeostasis. Mathematical modelling further suggests that the voltage-dependent vacuolar Ca\(^{2+}\) homeostat could contribute to calcium signalling when coupled to a recently discovered K\(^{+}\) channel-dependent module for electrical excitability of the vacuolar membrane. KW - voltage clamp KW - Arabidopsis thaliana KW - calcium signalling KW - computational cell biology KW - cpYFP cytosolic pH reporter KW - R-GECO1 cytosolic Ca\(^{2+}\) reporter KW - TPC1 channel KW - vacuolar membrane Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-259627 VL - 230 IS - 4 ER - TY - JOUR A1 - Fröschel, Christian T1 - In-depth evaluation of root infection systems using the vascular fungus Verticillium longisporum as soil-borne model pathogen JF - Plant Methods N2 - Background While leaves are far more accessible for analysing plant defences, roots are hidden in the soil, leading to difficulties in studying soil-borne interactions. Inoculation strategies for infecting model plants with model root pathogens are described in the literature, but it remains demanding to obtain a methodological overview. To address this challenge, this study uses the model root pathogen Verticillium longisporum on Arabidopsis thaliana host plants and provides recommendations for selecting appropriate infection systems to investigate how plants cope with root pathogens. Results A novel root infection system is introduced, while two existing ones are precisely described and optimized. Step-by-step protocols are presented and accompanied by pathogenicity tests, transcriptional analyses of indole-glucosinolate marker genes and independent confirmations using reporter constructs. Advantages and disadvantages of each infection system are assessed. Overall, the results validate the importance of indole-glucosinolates as secondary metabolites that limit the Verticillium propagation in its host plant. Conclusion Detailed assistances on studying host defence strategies and responses against V. longisporum is provided. Furthermore, other soil-borne microorganisms (e.g., V. dahliae) or model plants, such as economically important oilseed rape and tomato, can be introduced in the infection systems described. Hence, these proven manuals can support finding a root infection system for your specific research questions to further decipher root-microbe interactions. KW - Arabidopsis thaliana KW - Brassica napus KW - indole-glucosinolates KW - plant defence KW - root infection systems KW - root pathogens KW - soil-borne microorganisms KW - Solanum lycopersicum KW - Verticillium dahliae KW - Verticillium longisporum Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-260807 VL - 17 ER - TY - JOUR A1 - Rasouli, Fatemeh A1 - Kiani-Pouya, Ali A1 - Shabala, Lana A1 - Li, Leiting A1 - Tahir, Ayesha A1 - Yu, Min A1 - Hedrich, Rainer A1 - Chen, Zhonghua A1 - Wilson, Richard A1 - Zhang, Heng A1 - Shabala, Sergey T1 - Salinity effects on guard cell proteome in Chenopodium quinoa JF - International Journal of Molecular Sciences N2 - Epidermal fragments enriched in guard cells (GCs) were isolated from the halophyte quinoa (Chenopodium quinoa Wild.) species, and the response at the proteome level was studied after salinity treatment of 300 mM NaCl for 3 weeks. In total, 2147 proteins were identified, of which 36% were differentially expressed in response to salinity stress in GCs. Up and downregulated proteins included signaling molecules, enzyme modulators, transcription factors and oxidoreductases. The most abundant proteins induced by salt treatment were desiccation-responsive protein 29B (50-fold), osmotin-like protein OSML13 (13-fold), polycystin-1, lipoxygenase, alpha-toxin, and triacylglycerol lipase (PLAT) domain-containing protein 3-like (eight-fold), and dehydrin early responsive to dehydration (ERD14) (eight-fold). Ten proteins related to the gene ontology term “response to ABA” were upregulated in quinoa GC; this included aspartic protease, phospholipase D and plastid-lipid-associated protein. Additionally, seven proteins in the sucrose–starch pathway were upregulated in the GC in response to salinity stress, and accumulation of tryptophan synthase and L-methionine synthase (enzymes involved in the amino acid biosynthesis) was observed. Exogenous application of sucrose and tryptophan, L-methionine resulted in reduction in stomatal aperture and conductance, which could be advantageous for plants under salt stress. Eight aspartic proteinase proteins were highly upregulated in GCs of quinoa, and exogenous application of pepstatin A (an inhibitor of aspartic proteinase) was accompanied by higher oxidative stress and extremely low stomatal aperture and conductance, suggesting a possible role of aspartic proteinase in mitigating oxidative stress induced by saline conditions. KW - quinoa KW - guard cell KW - stomata KW - salt stress KW - proteomics analysis Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-285625 SN - 1422-0067 VL - 22 IS - 1 ER - TY - JOUR A1 - Huang, Shouguang A1 - Ding, Meiqi A1 - Roelfsema, M. Rob G. A1 - Dreyer, Ingo A1 - Scherzer, Sönke A1 - Al-Rasheid, Khaled A. S A1 - Gao, Shiqiang A1 - Nagel, Georg A1 - Hedrich, Rainer A1 - Konrad, Kai R. T1 - Optogenetic control of the guard cell membrane potential and stomatal movement by the light-gated anion channel GtACR1 JF - Science Advances N2 - Guard cells control the aperture of plant stomata, which are crucial for global fluxes of CO\(_2\) and water. In turn, guard cell anion channels are seen as key players for stomatal closure, but is activation of these channels sufficient to limit plant water loss? To answer this open question, we used an optogenetic approach based on the light-gated anion channelrhodopsin 1 (GtACR1). In tobacco guard cells that express GtACR1, blue- and green-light pulses elicit Cl\(^-\) and NO\(_3\)\(^-\) currents of -1 to -2 nA. The anion currents depolarize the plasma membrane by 60 to 80 mV, which causes opening of voltage-gated K+ channels and the extrusion of K+. As a result, continuous stimulation with green light leads to loss of guard cell turgor and closure of stomata at conditions that provoke stomatal opening in wild type. GtACR1 optogenetics thus provides unequivocal evidence that opening of anion channels is sufficient to close stomata. KW - abscisic-acid activation KW - Arabidopsis thaliana KW - H+-atpase KW - signal transduction KW - potassium channel KW - intact plants KW - K+ channels KW - R-type KW - CO2 KW - SLAC1 Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-260925 VL - 7 IS - 28 ER - TY - JOUR A1 - Schieferle, Sebastian A1 - Tappe, Beeke A1 - Korte, Pamela A1 - Mueller, Martin J. A1 - Berger, Susanne T1 - Pathogens and Elicitors Induce Local and Systemic Changes in Triacylglycerol Metabolism in Roots and in Leaves of Arabidopsis thaliana JF - Biology N2 - Simple Summary Abiotic and biotic stress conditions result in profound changes in plant lipid metabolism. Vegetable oil consists of triacylglycerols, which are important energy and carbon storage compounds in seeds of various plant species. These compounds are also present in vegetative tissue, and levels have been reported to increase with different abiotic stresses in leaves. This work shows that triacylglycerols accumulate in roots and in distal, non-treated leaves upon treatment with a fungal pathogen or lipopolysaccharide (a common bacterial-derived elicitor in animals and plants). Treatment of leaves with a bacterial pathogen or a bacterial effector molecule results in triacylglycerol accumulation in leaves, but not systemically in roots. These results suggest that elicitor molecules are sufficient to induce an increase in triacylglycerol levels, and that unidirectional long-distance signaling from roots to leaves is involved in pathogen and elicitor-induced triacylglycerol accumulation. Abstract Interaction of plants with the environment affects lipid metabolism. Changes in the pattern of phospholipids have been reported in response to abiotic stress, particularly accumulation of triacylglycerols, but less is known about the alteration of lipid metabolism in response to biotic stress and leaves have been more intensively studied than roots. This work investigates the levels of lipids in roots as well as leaves of Arabidopsis thaliana in response to pathogens and elicitor molecules by UPLC-TOF-MS. Triacylglycerol levels increased in roots and systemically in leaves upon treatment of roots with the fungus Verticillium longisporum. Upon spray infection of leaves with the bacterial pathogen Pseudomonas syringae, triacylglycerols accumulated locally in leaves but not in roots. Treatment of roots with a bacterial lipopolysaccharide elicitor induced a strong triacylglycerol accumulation in roots and leaves. Induction of the expression of the bacterial effector AVRRPM1 resulted in a dramatic increase of triacylglycerol levels in leaves, indicating that elicitor molecules are sufficient to induce accumulation of triacylglycerols. These results give insight into local and systemic changes to lipid metabolism in roots and leaves in response to biotic stresses. KW - triacylglycerols KW - membrane remodeling KW - pathogens KW - elicitors KW - effectors Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-246198 SN - 2079-7737 VL - 10 IS - 9 ER - TY - JOUR A1 - Ghirardo, Andrea A1 - Nosenko, Tetyana A1 - Kreuzwieser, Jürgen A1 - Winkler, J. Barbro A1 - Kruse, Jörg A1 - Albert, Andreas A1 - Merl-Pham, Juliane A1 - Lux, Thomas A1 - Ache, Peter A1 - Zimmer, Ina A1 - Alfarraj, Saleh A1 - Mayer, Klaus F. X. A1 - Hedrich, Rainer A1 - Rennenberg, Heinz A1 - Schnitzler, Jörg-Peter T1 - Protein expression plasticity contributes to heat and drought tolerance of date palm JF - Oecologia N2 - Climate change is increasing the frequency and intensity of warming and drought periods around the globe, currently representing a threat to many plant species. Understanding the resistance and resilience of plants to climate change is, therefore, urgently needed. As date palm (Phoenix dactylifera) evolved adaptation mechanisms to a xeric environment and can tolerate large diurnal and seasonal temperature fluctuations, we studied the protein expression changes in leaves, volatile organic compound emissions, and photosynthesis in response to variable growth temperatures and soil water deprivation. Plants were grown under controlled environmental conditions of simulated Saudi Arabian summer and winter climates challenged with drought stress. We show that date palm is able to counteract the harsh conditions of the Arabian Peninsula by adjusting the abundances of proteins related to the photosynthetic machinery, abiotic stress and secondary metabolism. Under summer climate and water deprivation, these adjustments included efficient protein expression response mediated by heat shock proteins and the antioxidant system to counteract reactive oxygen species formation. Proteins related to secondary metabolism were downregulated, except for the P. dactylifera isoprene synthase (PdIspS), which was strongly upregulated in response to summer climate and drought. This study reports, for the first time, the identification and functional characterization of the gene encoding for PdIspS, allowing future analysis of isoprene functions in date palm under extreme environments. Overall, the current study shows that reprogramming of the leaf protein profiles confers the date palm heat- and drought tolerance. We conclude that the protein plasticity of date palm is an important mechanism of molecular adaptation to environmental fluctuations. KW - abiotic stress KW - isoprene KW - proteomics KW - photosynthesis KW - Phoenix dactylifera Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-308075 SN - 0029-8549 SN - 1432-1939 VL - 197 IS - 4 ER - TY - JOUR A1 - Dorji, Yonten A1 - Schuldt, Bernhard A1 - Neudam, Liane A1 - Dorji, Rinzin A1 - Middleby, Kali A1 - Isasa, Emilie A1 - Körber, Klaus A1 - Ammer, Christian A1 - Annighöfer, Peter A1 - Seidel, Dominik T1 - Three-dimensional quantification of tree architecture from mobile laser scanning and geometry analysis JF - Trees N2 - Key message Mobile laser scanning and geometrical analysis revealed relationships between tree geometry and seed dispersal mechanism, latitude of origin, as well as growth. Abstract The structure and dynamics of a forest are defined by the architecture and growth patterns of its individual trees. In turn, tree architecture and growth result from the interplay between the genetic building plans and environmental factors. We set out to investigate whether (1) latitudinal adaptations of the crown shape occur due to characteristic solar elevation angles at a species’ origin, (2) architectural differences in trees are related to seed dispersal strategies, and (3) tree architecture relates to tree growth performance. We used mobile laser scanning (MLS) to scan 473 trees and generated three-dimensional data of each tree. Tree architectural complexity was then characterized by fractal analysis using the box-dimension approach along with a topological measure of the top heaviness of a tree. The tree species studied originated from various latitudinal ranges, but were grown in the same environmental settings in the arboretum. We found that trees originating from higher latitudes had significantly less top-heavy geometries than those from lower latitudes. Therefore, to a certain degree, the crown shape of tree species seems to be determined by their original habitat. We also found that tree species with wind-dispersed seeds had a higher structural complexity than those with animal-dispersed seeds (p < 0.001). Furthermore, tree architectural complexity was positively related to the growth performance of the trees (p < 0.001). We conclude that the use of 3D data from MLS in combination with geometrical analysis, including fractal analysis, is a promising tool to investigate tree architecture. KW - tree architecture KW - LiDAR KW - fractal analysis KW - seed dispersal strategy KW - latitude KW - tree growth Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-307501 SN - 0931-1890 SN - 1432-2285 VL - 35 IS - 4 ER - TY - JOUR A1 - Krauss, Jochen A1 - Vikuk, Veronika A1 - Young, Carolyn A. A1 - Krischke, Markus A1 - Mueller, Martin J. A1 - Baerenfaller, Katja T1 - Epichloë endophyte infection rates and alkaloid content in commercially available grass seed mixtures in Europe JF - Microorganisms N2 - Fungal endophytes of the genus Epichloë live symbiotically in cool season grass species and can produce alkaloids toxic to insects and vertebrates, yet reports of intoxication of grazing animals have been rare in Europe in contrast to overseas. However, due to the beneficial resistance traits observed in Epichloë infected grasses, the inclusion of Epichloë in seed mixtures might become increasingly advantageous. Despite the toxicity of fungal alkaloids, European seed mixtures are rarely tested for Epichloë infection and their infection status is unknown for consumers. In this study, we tested 24 commercially available seed mixtures for their infection rates with Epichloë endophytes and measured the concentrations of the alkaloids ergovaline, lolitrem B, paxilline, and peramine. We detected Epichloë infections in six seed mixtures, and four contained vertebrate and insect toxic alkaloids typical for Epichloë festucae var. lolii infecting Lolium perenne. As Epichloë infected seed mixtures can harm livestock, when infected grasses become dominant in the seeded grasslands, we recommend seed producers to test and communicate Epichloë infection status or avoiding Epichloë infected seed mixtures. KW - Epichloë spp. KW - grass endophytes KW - cool-season grass species KW - infection rates KW - alkaloids KW - toxicity KW - livestock KW - horses KW - Lolium perenne KW - perennial ryegrass Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-203323 SN - 2076-2607 VL - 8 IS - 4 ER - TY - JOUR A1 - Krauss, Jochen A1 - Vikuk, Veronika A1 - Young, Carolyn A. A1 - Krischke, Markus A1 - Mueller, Martin J. A1 - Baerenfaller, Katja T1 - Correction: Krauss, J., et al. Epichloë endophyte infection rates and alkaloid content in commercially available grass seed mixtures in Europe. Microorganisms 2020, 8, 498 JF - Microorganisms N2 - No abstract available. KW - Epichloë KW - endophyte Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-216254 SN - 2076-2607 VL - 8 IS - 10 ER - TY - JOUR A1 - Thurow, Corinna A1 - Krischke, Markus A1 - Mueller, Martin J. A1 - Gatz, Christiane T1 - Induction of jasmonoyl-isoleucine (JA-Ile)-dependent JASMONATE ZIM-DOMAIN (JAZ) genes in NaCl-treated Arabidopsis thaliana roots can occur at very low JA-Ile levels and in the absence of the JA/JA-Ile transporter JAT1/AtABCG16 JF - Plants N2 - The plant hormone jasmonoyl-isoleucine (JA-Ile) is an important regulator of plant growth and defense in response to various biotic and abiotic stress cues. Under our experimental conditions, JA-Ile levels increased approximately seven-fold in NaCl-treated Arabidopsis thaliana roots. Although these levels were around 1000-fold lower than in wounded leaves, genes of the JA-Ile signaling pathway were induced by a factor of 100 or more. Induction was severely compromised in plants lacking the JA-Ile receptor CORONATINE INSENSITIVE 1 or enzymes required for JA-Ile biosynthesis. To explain efficient gene expression at very low JA-Ile levels, we hypothesized that salt-induced expression of the JA/JA-Ile transporter JAT1/AtABCG16 would lead to increased nuclear levels of JA-Ile. However, mutant plants with different jat1 alleles were similar to wild-type ones with respect to salt-induced gene expression. The mechanism that allows COI1-dependent gene expression at very low JA-Ile levels remains to be elucidated. KW - allene oxide synthase KW - CORONATINE INSENSITIVE 1 KW - jasmonoyl-isoleucine KW - JA/JA-Ile transport protein JAT1 KW - roots KW - salt Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-219382 SN - 2223-7747 VL - 9 IS - 12 ER - TY - JOUR A1 - Ellsäßer, Florian A1 - Röll, Alexander A1 - Ahongshangbam, Joyson A1 - Waite, Pierre-André A1 - Hendrayanto, A1 - Schuldt, Bernhard A1 - Hölscher, Dirk T1 - Predicting tree sap flux and stomatal conductance from drone-recorded surface temperatures in a mixed agroforestry system — a machine learning approach JF - Remote Sensing N2 - Plant transpiration is a key element in the hydrological cycle. Widely used methods for its assessment comprise sap flux techniques for whole-plant transpiration and porometry for leaf stomatal conductance. Recently emerging approaches based on surface temperatures and a wide range of machine learning techniques offer new possibilities to quantify transpiration. The focus of this study was to predict sap flux and leaf stomatal conductance based on drone-recorded and meteorological data and compare these predictions with in-situ measured transpiration. To build the prediction models, we applied classical statistical approaches and machine learning algorithms. The field work was conducted in an oil palm agroforest in lowland Sumatra. Random forest predictions yielded the highest congruence with measured sap flux (r\(^2\) = 0.87 for trees and r\(^2\) = 0.58 for palms) and confidence intervals for intercept and slope of a Passing-Bablok regression suggest interchangeability of the methods. Differences in model performance are indicated when predicting different tree species. Predictions for stomatal conductance were less congruent for all prediction methods, likely due to spatial and temporal offsets of the measurements. Overall, the applied drone and modelling scheme predicts whole-plant transpiration with high accuracy. We conclude that there is large potential in machine learning approaches for ecological applications such as predicting transpiration. KW - transpiration KW - method comparison KW - UAV KW - oil palm KW - multiple linear regression KW - support vector machine KW - random forest KW - artificial neural network Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-220059 SN - 2072-4292 VL - 12 IS - 24 ER - TY - JOUR A1 - Fuchs, Sebastian A1 - Hertel, Dietrich A1 - Schuldt, Bernhard A1 - Leuschner, Christoph T1 - Effects of summer drought on the fine root system of five broadleaf tree species along a precipitation gradient JF - Forests N2 - While much research has addressed the aboveground response of trees to climate warming and related water shortage, not much is known about the drought sensitivity of the fine root system, in particular of mature trees. This study investigates the response of topsoil (0–10 cm) fine root biomass (FRB), necromass (FRN), and fine root morphology of five temperate broadleaf tree species (Acer platanoides L., Carpinus betulus L., Fraxinus excelsior L., Quercus petraea (Matt.) Liebl., Tilia cordata Mill.) to a reduction in water availability, combining a precipitation gradient study (nine study sites; mean annual precipitation (MAP): 920–530 mm year\(^{−1}\)) with the comparison of a moist period (average spring conditions) and an exceptionally dry period in the summer of the subsequent year. The extent of the root necromass/biomass (N/B) ratio increase was used as a measure of the species’ belowground sensitivity to water deficits. We hypothesized that the N/B ratio increases with long-term (precipitation gradient) and short-term reductions (moist vs. dry period) of water availability, while FRB changes only a little. In four of the five species (exception: A. platanoides), FRB did not change with a reduction in MAP, whereas FRN and N/B ratio increased toward the dry sites under ample water supply (exception: Q. petraea). Q. petraea was also the only species not to reduce root tip frequency after summer drought. Different slopes of the N/B ratio-MAP relation similarly point at a lower belowground drought sensitivity of Q. petraea than of the other species. After summer drought, all species lost the MAP dependence of the N/B ratio. Thus, fine root mortality increased more at the moister than the drier sites, suggesting a generally lower belowground drought sensitivity of the drier stands. We conclude that the five species differ in their belowground drought response. Q. petraea follows the most conservative soil exploration strategy with a generally smaller FRB and more drought-tolerant fine roots, as it maintains relatively constant FRB, FRN, and morphology across spatial and temporal dimensions of soil water deficits. KW - Acer platanoides KW - Carpinus betulus KW - fine root biomass KW - fine root necromass KW - Fraxinus excelsior KW - necromass/biomass ratio KW - Quercus petraea KW - root morphology KW - Tilia cordata KW - water availability Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-203189 SN - 1999-4907 VL - 11 IS - 3 ER - TY - JOUR A1 - Vikuk, Veronika A1 - Fuchs, Benjamin A1 - Krischke, Markus A1 - Mueller, Martin J. A1 - Rueb, Selina A1 - Krauss, Jochen T1 - Alkaloid Concentrations of Lolium perenne Infected with Epichloë festucae var. lolii with Different Detection Methods—A Re-Evaluation of Intoxication Risk in Germany? JF - Journal of Fungi N2 - Mycotoxins in agriculturally used plants can cause intoxication in animals and can lead to severe financial losses for farmers. The endophytic fungus Epichloë festucae var. lolii living symbiotically within the cool season grass species Lolium perenne can produce vertebrate and invertebrate toxic alkaloids. Hence, an exact quantitation of alkaloid concentrations is essential to determine intoxication risk for animals. Many studies use different methods to detect alkaloid concentrations, which complicates the comparability. In this study, we showed that alkaloid concentrations of individual plants exceeded toxicity thresholds on real world grasslands in Germany, but not on the population level. Alkaloid concentrations on five German grasslands with high alkaloid levels peaked in summer but were also below toxicity thresholds on population level. Furthermore, we showed that alkaloid concentrations follow the same seasonal trend, regardless of whether plant fresh or dry weight was used, in the field and in a common garden study. However, alkaloid concentrations were around three times higher when detected with dry weight. Finally, we showed that alkaloid concentrations can additionally be biased to different alkaloid detection methods. We highlight that toxicity risks should be analyzed using plant dry weight, but concentration trends of fresh weight are reliable. KW - Epichloë KW - Lolium perenne KW - toxicity KW - grasslands KW - HPLC/UPLC methods KW - endophyte KW - plant fresh/dry weight KW - alkaloid detection methods KW - mycotoxins KW - phenology Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-213171 SN - 2309-608X VL - 6 IS - 3 ER - TY - JOUR A1 - Osman, Mohamed A1 - Stigloher, Christian A1 - Mueller, Martin J. A1 - Waller, Frank T1 - An improved growth medium for enhanced inoculum production of the plant growth-promoting fungus Serendipita indica JF - Plant Methods N2 - Background The plant endophytic fungus Serendipita indica colonizes roots of a wide range of plant species and can enhance growth and stress resistance of these plants. Due to its ease of axenic cultivation and its broad host plant range including the model plant Arabidopsis thaliana and numerous crop plants, it is widely used as a model fungus to study beneficial fungus-root interactions. In addition, it was suggested to be utilized for commercial applications, e.g. to enhance yield in barley and other species. To produce inoculum, S. indica is mostly cultivated in a complex Hill-Kafer medium (CM medium), however, growth in this medium is slow, and yield of chlamydospores, which are often used for plant root inoculation, is relatively low. Results We tested and optimized a simple vegetable juice-based medium for an enhanced yield of fungal inoculum. The described vegetable juice (VJ) medium is based on commercially available vegetable juice and is easy to prepare. VJ medium was superior to the currently used CM medium with respect to biomass production in liquid medium and hyphal growth on agar plates. Using solid VJ medium supplemented with sucrose (VJS), a high amount of chlamydospores developed already after 8 days of cultivation, producing significantly more spores than on CM medium. Use of VJ medium is not restricted to S. indica, as it also supported growth of two pathogenic fungi often used in plant pathology experiments: the ascomycete Fusarium graminearum, the causal agent of Fusarium head blight disease on wheat and barley, and Verticillium longisporum, the causal agent of verticillium wilt. Conclusions The described VJ medium is recommended for streamlined and efficient production of inoculum for the plant endophytic fungus Serendipita indica and might prove superior for the propagation of other fungi for research purposes. KW - Serendipita indica KW - Plant root endophyte KW - Inoculum production KW - Complex medium KW - Aspergillus medium KW - Vegetable juice KW - Plant growth promotion Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-229186 VL - 16 ER - TY - JOUR A1 - Schäbler, Stefan A1 - Amatobi, Kelechi M. A1 - Horn, Melanie A1 - Rieger, Dirk A1 - Helfrich‑Förster, Charlotte A1 - Mueller, Martin J. A1 - Wegener, Christian A1 - Fekete, Agnes T1 - Loss of function in the Drosophila clock gene period results in altered intermediary lipid metabolism and increased susceptibility to starvation JF - Cellular and Molecular Life Sciences N2 - The fruit fly Drosophila is a prime model in circadian research, but still little is known about its circadian regulation of metabolism. Daily rhythmicity in levels of several metabolites has been found, but knowledge about hydrophobic metabolites is limited. We here compared metabolite levels including lipids between period\(^{01}\) (per\(^{01}\)) clock mutants and Canton-S wildtype (WT\(_{CS}\)) flies in an isogenic and non-isogenic background using LC–MS. In the non-isogenic background, metabo-lites with differing levels comprised essential amino acids, kynurenines, pterinates, glycero(phospho)lipids, and fatty acid esters. Notably, detectable diacylglycerols (DAG) and acylcarnitines (AC), involved in lipid metabolism, showed lower levels in per\(^{01}\) mutants. Most of these differences disappeared in the isogenic background, yet the level differences for AC as well as DAG were consistent for fly bodies. AC levels were dependent on the time of day in WTCS in phase with food consumption under LD conditions, while DAGs showed weak daily oscillations. Two short-chain ACs continued to cycle even in constant darkness. per\(^{01}\) mutants in LD showed no or very weak diel AC oscillations out of phase with feeding activity. The low levels of DAGs and ACs in per\(^{01}\) did not correlate with lower total food consumption, body mass or weight. Clock mutant flies showed higher sensitivity to starvation independent of their background-dependent activity level. Our results suggest that neither feeding, energy storage nor mobilisation is significantly affected in per\(^{01}\) mutants, but point towards impaired mitochondrial activity, supported by upregulation of the mitochondrial stress marker 4EBP in the clock mutants KW - circadian rhythms KW - metabolomics KW - mitochondrial activity KW - tryptophan KW - acylcarnitine KW - feeding Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-232432 SN - 1420-682X VL - 77 ER - TY - JOUR A1 - Fukushima, Kenji A1 - Pollock, David D. T1 - Amalgamated cross-species transcriptomes reveal organ-specific propensity in gene expression evolution JF - Nature Communications N2 - The origins of multicellular physiology are tied to evolution of gene expression. Genes can shift expression as organisms evolve, but how ancestral expression influences altered descendant expression is not well understood. To examine this, we amalgamate 1,903 RNA-seq datasets from 182 research projects, including 6 organs in 21 vertebrate species. Quality control eliminates project-specific biases, and expression shifts are reconstructed using gene-family-wise phylogenetic Ornstein-Uhlenbeck models. Expression shifts following gene duplication result in more drastic changes in expression properties than shifts without gene duplication. The expression properties are tightly coupled with protein evolutionary rate, depending on whether and how gene duplication occurred. Fluxes in expression patterns among organs are nonrandom, forming modular connections that are reshaped by gene duplication. Thus, if expression shifts, ancestral expression in some organs induces a strong propensity for expression in particular organs in descendants. Regardless of whether the shifts are adaptive or not, this supports a major role for what might be termed preadaptive pathways of gene expression evolution. KW - phylogenetic trees KW - adaptive conflict KW - divergence times KW - duplicate genes KW - recent origin KW - package KW - selection KW - alignmen KW - rates KW - biology Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-230468 VL - 11, ER - TY - JOUR A1 - Kunz, Tobias C. A1 - Götz, Ralph A1 - Gao, Shiqiang A1 - Sauer, Markus A1 - Kozjak-Pavlovic, Vera T1 - Using Expansion Microscopy to Visualize and Characterize the Morphology of Mitochondrial Cristae JF - Frontiers in Cell and Developmental Biology N2 - Mitochondria are double membrane bound organelles indispensable for biological processes such as apoptosis, cell signaling, and the production of many important metabolites, which includes ATP that is generated during the process known as oxidative phosphorylation (OXPHOS). The inner membrane contains folds called cristae, which increase the membrane surface and thus the amount of membrane-bound proteins necessary for the OXPHOS. These folds have been of great interest not only because of their importance for energy conversion, but also because changes in morphology have been linked to a broad range of diseases from cancer, diabetes, neurodegenerative diseases, to aging and infection. With a distance between opposing cristae membranes often below 100 nm, conventional fluorescence imaging cannot provide a resolution sufficient for resolving these structures. For this reason, various highly specialized super-resolution methods including dSTORM, PALM, STED, and SIM have been applied for cristae visualization. Expansion Microscopy (ExM) offers the possibility to perform super-resolution microscopy on conventional confocal microscopes by embedding the sample into a swellable hydrogel that is isotropically expanded by a factor of 4–4.5, improving the resolution to 60–70 nm on conventional confocal microscopes, which can be further increased to ∼ 30 nm laterally using SIM. Here, we demonstrate that the expression of the mitochondrial creatine kinase MtCK linked to marker protein GFP (MtCK-GFP), which localizes to the space between the outer and the inner mitochondrial membrane, can be used as a cristae marker. Applying ExM on mitochondria labeled with this construct enables visualization of morphological changes of cristae and localization studies of mitochondrial proteins relative to cristae without the need for specialized setups. For the first time we present the combination of specific mitochondrial intermembrane space labeling and ExM as a tool for studying internal structure of mitochondria. KW - Expansion microscopy KW - mitochondria KW - cristae KW - structured illumination microscope KW - ultrastructure Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-208296 SN - 2296-634X VL - 8 ER - TY - JOUR A1 - Ferber, Elena A1 - Gerhards, Julian A1 - Sauer, Miriam A1 - Krischke, Markus A1 - Dittrich, Marcus T. A1 - Müller, Tobias A1 - Berger, Susanne A1 - Fekete, Agnes A1 - Mueller, Martin J. T1 - Chemical Priming by Isothiocyanates Protects Against Intoxication by Products of the Mustard Oil Bomb JF - Frontiers in Plant Science N2 - In Brassicaceae, tissue damage triggers the mustard oil bomb i.e., activates the degradation of glucosinolates by myrosinases leading to a rapid accumulation of isothiocyanates at the site of damage. Isothiocyanates are reactive electrophilic species (RES) known to covalently bind to thiols in proteins and glutathione, a process that is not only toxic to herbivores and microbes but can also cause cell death of healthy plant tissues. Previously, it has been shown that subtoxic isothiocyanate concentrations can induce transcriptional reprogramming in intact plant cells. Glutathione depletion by RES leading to breakdown of the redox potential has been proposed as a central and common RES signal transduction mechanism. Using transcriptome analyses, we show that after exposure of Arabidopsis seedlings (grown in liquid culture) to subtoxic concentrations of sulforaphane hundreds of genes were regulated without depletion of the cellular glutathione pool. Heat shock genes were among the most highly up-regulated genes and this response was found to be dependent on the canonical heat shock factors A1 (HSFA1). HSFA1-deficient plants were more sensitive to isothiocyanates than wild type plants. Moreover, pretreatment of Arabidopsis seedlings with subtoxic concentrations of isothiocyanates increased resistance against exposure to toxic levels of isothiocyanates and, hence, may reduce the autotoxicity of the mustard oil bomb by inducing cell protection mechanisms. KW - autotoxicity KW - heat shock response KW - isothiocyanates KW - mustard oil bomb KW - reactive electrophilic species KW - redox homeostasis KW - sulforaphane Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-207104 SN - 1664-462X VL - 11 ER - TY - JOUR A1 - Rasouli, Fatemeh A1 - Kiani-Pouya, Ali A1 - Li, Leiting A1 - Zhang, Heng A1 - Chen, Zhonghua A1 - Hedrich, Rainer A1 - Wilson, Richard A1 - Shabala, Sergey T1 - Sugar beet (Beta vulgaris) guard cells responses to salinity stress: a proteomic analysis JF - International Journal of Molecular Sciences N2 - Soil salinity is a major environmental constraint affecting crop growth and threatening global food security. Plants adapt to salinity by optimizing the performance of stomata. Stomata are formed by two guard cells (GCs) that are morphologically and functionally distinct from the other leaf cells. These microscopic sphincters inserted into the wax-covered epidermis of the shoot balance CO\(_2\) intake for photosynthetic carbon gain and concomitant water loss. In order to better understand the molecular mechanisms underlying stomatal function under saline conditions, we used proteomics approach to study isolated GCs from the salt-tolerant sugar beet species. Of the 2088 proteins identified in sugar beet GCs, 82 were differentially regulated by salt treatment. According to bioinformatics analysis (GO enrichment analysis and protein classification), these proteins were involved in lipid metabolism, cell wall modification, ATP biosynthesis, and signaling. Among the significant differentially abundant proteins, several proteins classified as “stress proteins” were upregulated, including non-specific lipid transfer protein, chaperone proteins, heat shock proteins, inorganic pyrophosphatase 2, responsible for energized vacuole membrane for ion transportation. Moreover, several antioxidant enzymes (peroxide, superoxidase dismutase) were highly upregulated. Furthermore, cell wall proteins detected in GCs provided some evidence that GC walls were more flexible in response to salt stress. Proteins such as L-ascorbate oxidase that were constitutively high under both control and high salinity conditions may contribute to the ability of sugar beet GCs to adapt to salinity by mitigating salinity-induced oxidative stress. KW - guard cells KW - stomata KW - sugar beet KW - salt stress KW - proteomic Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-285765 SN - 1422-0067 VL - 21 IS - 7 ER - TY - JOUR A1 - Geiger, Dietmar T1 - Plant glucose transporter structure and function JF - Pflügers Archiv - European Journal of Physiology N2 - The carbohydrate D-glucose is the main source of energy in living organisms. In contrast to animals, as well as most fungi, bacteria, and archaea, plants are capable to synthesize a surplus of sugars characterizing them as autothrophic organisms. Thus, plants are de facto the source of all food on earth, either directly or indirectly via feed to livestock. Glucose is stored as polymeric glucan, in animals as glycogen and in plants as starch. Despite serving a general source for metabolic energy and energy storage, glucose is the main building block for cellulose synthesis and represents the metabolic starting point of carboxylate- and amino acid synthesis. Finally yet importantly, glucose functions as signalling molecule conveying the plant metabolic status for adjustment of growth, development, and survival. Therefore, cell-to-cell and long-distance transport of photoassimilates/sugars throughout the plant body require the fine-tuned activity of sugar transporters facilitating the transport across membranes. The functional plant counterparts of the animal sodium/glucose transporters (SGLTs) are represented by the proton-coupled sugar transport proteins (STPs) of the plant monosaccharide transporter(-like) family (MST). In the framework of this special issue on “Glucose Transporters in Health and Disease,” this review gives an overview of the function and structure of plant STPs in comparison to the respective knowledge obtained with the animal Na+-coupled glucose transporters (SGLTs). KW - STP KW - sugar transport protein KW - glucose transport KW - plant photoassimilate partitioning Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-280643 VL - 472 IS - 9 ER - TY - JOUR A1 - Li, Shan A1 - Li, Xin A1 - Link, Roman A1 - Li, Ren A1 - Deng, Liping A1 - Schuldt, Bernhard A1 - Jiang, Xiaomei A1 - Zhao, Rongjun A1 - Zheng, Jingming A1 - Li, Shuang A1 - Yin, Yafang T1 - Influence of cambial age and axial height on the spatial patterns of xylem traits in Catalpa bungei, a ring-porous tree species native to China JF - Forests N2 - Studying how cambial age and axial height affects wood anatomical traits may improve our understanding of xylem hydraulics, heartwood formation and axial growth. Radial strips were collected from six different heights (0–11.3 m) along the main trunk of three Manchurian catalpa (Catalpa bungei) trees, yielding 88 samples. In total, thirteen wood anatomical vessel and fiber traits were observed usinglight microscopy (LM) and scanning electron microscopy (SEM), and linear models were used to analyse the combined effect of axial height, cambial age and their interaction. Vessel diameter differed by about one order of magnitude between early- and latewood, and increased significantly with both cambial age and axial height in latewood, while it was positively affected by cambial age and independent of height in earlywood. Vertical position further had a positive effect on earlywood vessel density, and negative effects on fibre wall thickness, wall thickness to diameter ratio and length. Cambial age had positive effects on the pit membrane diameter and vessel element length, while the annual diameter growth decreased with both cambial age and axial position. In contrast, early- and latewood fiber diameter were unaffected by both cambial age and axial height. We further observed an increasing amount of tyloses from sapwood to heartwood, accompanied by an increase of warty layers and amorphous deposits on cell walls, bordered pit membranes and pit apertures. This study highlights the significant effects of cambial age and vertical position on xylem anatomical traits, and confirms earlier work that cautions to take into account xylem spatial position when interpreting wood anatomical structures, and thus, xylem hydraulic functioning. KW - wood anatomy KW - vertical and radial variation KW - earlywood KW - latewood KW - growth ring width KW - tyloses KW - pit membrane diameter KW - vessel lumen diameter KW - fibre length Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-196297 SN - 1999-4907 VL - 10 IS - 8 ER - TY - JOUR A1 - Nickel, Joachim A1 - Mueller, Thomas D. T1 - Specification of BMP signaling JF - Cells N2 - Bone Morphogenetic Proteins (BMPs) together with the Growth and Differentiation Factors (GDFs) form the largest subgroup of the Transforming Growth Factor (TGF)β family and represent secreted growth factors, which play an essential role in many aspects of cell communication in higher organisms. As morphogens they exert crucial functions during embryonal development, but are also involved in tissue homeostasis and regeneration in the adult organism. Their involvement in maintenance and repair processes of various tissues and organs made these growth factors highly interesting targets for novel pharmaceutical applications in regenerative medicine. A hallmark of the TGFβ protein family is that all of the more than 30 growth factors identified to date signal by binding and hetero-oligomerization of a very limited set of transmembrane serine-threonine kinase receptors, which can be classified into two subgroups termed type I and type II. Only seven type I and five type II receptors exist for all 30plus TGFβ members suggesting a pronounced ligand-receptor promiscuity. Indeed, many TGFβ ligands can bind the same type I or type II receptor and a particular receptor of either subtype can usually interact with and bind various TGFβ ligands. The possible consequence of this ligand-receptor promiscuity is further aggravated by the finding that canonical TGFβ signaling of all family members seemingly results in the activation of just two distinct signaling pathways, that is either SMAD2/3 or SMAD1/5/8 activation. While this would implicate that different ligands can assemble seemingly identical receptor complexes that activate just either one of two distinct pathways, in vitro and in vivo analyses show that the different TGFβ members exert quite distinct biological functions with high specificity. This discrepancy indicates that our current view of TGFβ signaling initiation just by hetero-oligomerization of two receptor subtypes and transduction via two main pathways in an on-off switch manner is too simplified. Hence, the signals generated by the various TGFβ members are either quantitatively interpreted using the subtle differences in their receptor-binding properties leading to ligand-specific modulation of the downstream signaling cascade or additional components participating in the signaling activation complex allow diversification of the encoded signal in a ligand-dependent manner at all cellular levels. In this review we focus on signal specification of TGFβ members, particularly of BMPs and GDFs addressing the role of binding affinities, specificities, and kinetics of individual ligand-receptor interactions for the assembly of specific receptor complexes with potentially distinct signaling properties. KW - TGFβ/BMP signaling KW - ligand-receptor promiscuity KW - signal specification Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-193869 SN - 2073-4409 VL - 8 IS - 12 ER - TY - JOUR A1 - Elmaidomy, Abeer H. A1 - Mohammed, Rabab A1 - Hassan, Hossam M. A1 - Owis, Asmaa I. A1 - Rateb, Mostafa E. A1 - Khanfar, Mohammad A. A1 - Krischke, Markus A1 - Mueller, Martin J. A1 - Abdelmohsen, Usama Ramadan T1 - Metabolomic profiling and cytotoxic tetrahydrofurofuran lignans investigations from Premna odorata Blanco JF - Metabolites N2 - Metabolomic profiling of different Premna odorata Blanco (Lamiaceae) organs, bark, wood, young stems, flowers, and fruits dereplicated 20, 20, 10, 20, and 20 compounds, respectively, using LC–HRESIMS. The identified metabolites (1–34) belonged to different chemical classes, including iridoids, flavones, phenyl ethanoids, and lignans. A phytochemical investigation of P. odorata bark afforded one new tetrahydrofurofuran lignan, 4β-hydroxyasarinin 35, along with fourteen known compounds. The structure of the new compound was confirmed using extensive 1D and 2D NMR, and HRESIMS analyses. A cytotoxic investigation of compounds 35–38 against the HL-60, HT-29, and MCF-7 cancer cell lines, using the MTT assay showed that compound 35 had cytotoxic effects against HL-60 and MCF-7 with IC50 values of 2.7 and 4.2 µg/mL, respectively. A pharmacophore map of compounds 35 showed two hydrogen bond acceptor (HBA) aligning the phenoxy oxygen atoms of benzodioxole moieties, two aromatic ring features vectored on the two phenyl rings, one hydrogen bond donor (HBD) feature aligning the central hydroxyl group and thirteen exclusion spheres which limit the boundaries of sterically inaccessible regions of the target’s active site. KW - Premna KW - lignan KW - metabolomic KW - cytotoxic KW - pharmacophore map Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-193187 SN - 2218-1989 VL - 9 IS - 10 ER - TY - JOUR A1 - Duan, Xiaodong A1 - Nagel, Georg A1 - Gao, Shiqiang T1 - Mutated channelrhodopsins with increased sodium and calcium permeability JF - Applied Sciences N2 - (1) Background: After the discovery and application of Chlamydomonas reinhardtii channelrhodopsins, the optogenetic toolbox has been greatly expanded with engineered and newly discovered natural channelrhodopsins. However, channelrhodopsins of higher Ca\(^{2+}\) conductance or more specific ion permeability are in demand. (2) Methods: In this study, we mutated the conserved aspartate of the transmembrane helix 4 (TM4) within Chronos and PsChR and compared them with published ChR2 aspartate mutants. (3) Results: We found that the ChR2 D156H mutant (XXM) showed enhanced Na\(^+\) and Ca\(^{2+}\) conductance, which was not noticed before, while the D156C mutation (XXL) influenced the Na\(^+\) and Ca\(^{2+}\) conductance only slightly. The aspartate to histidine and cysteine mutations of Chronos and PsChR also influenced their photocurrent, ion permeability, kinetics, and light sensitivity. Most interestingly, PsChR D139H showed a much-improved photocurrent, compared to wild type, and even higher Na+ selectivity to H\(^+\) than XXM. PsChR D139H also showed a strongly enhanced Ca\(^{2+}\) conductance, more than two-fold that of the CatCh. (4) Conclusions: We found that mutating the aspartate of the TM4 influences the ion selectivity of channelrhodopsins. With the large photocurrent and enhanced Na\(^+\) selectivity and Ca\(^{2+}\) conductance, XXM and PsChR D139H are promising powerful optogenetic tools, especially for Ca\(^{2+}\) manipulation. KW - optogenetics KW - channelrhodopsins KW - sodium KW - calcium KW - DC gate Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-197435 SN - 2076-3417 VL - 9 IS - 4 ER - TY - JOUR A1 - Youssif, Khayrya A. A1 - Haggag, Eman G. A1 - Elshamy, Ali M. A1 - Rabeh, Mohamed A. A1 - Gabr, Nagwan M. A1 - Seleem, Amany A1 - Salem, M. Alaraby A1 - Hussein, Ahmed S. A1 - Krischke, Markus A1 - Mueller, Martin J. A1 - Ramadan Abdelmohsen, Usama T1 - Anti-Alzheimer potential, metabolomic profiling and molecular docking of green synthesized silver nanoparticles of Lampranthus coccineus and Malephora lutea aqueous extracts JF - PLoS ONE N2 - The green synthesis of silver nanoparticles (SNPs) using plant extracts is an eco-friendly method. It is a single step and offers several advantages such as time reducing, cost-effective and environmental non-toxic. Silver nanoparticles are a type of Noble metal nanoparticles and it has tremendous applications in the field of diagnostics, therapeutics, antimicrobial activity, anticancer and neurodegenerative diseases. In the present work, the aqueous extracts of aerial parts of Lampranthus coccineus and Malephora lutea F. Aizoaceae were successfully used for the synthesis of silver nanoparticles. The formation of silver nanoparticles was early detected by a color change from pale yellow to reddish-brown color and was further confirmed by transmission electron microscope (TEM), UV–visible spectroscopy, Fourier transform infrared (FTIR) spectroscopy, dynamic light scattering (DLS), X-ray diffraction (XRD), and energy-dispersive X-ray diffraction (EDX). The TEM analysis of showed spherical nanoparticles with a mean size between 12.86 nm and 28.19 nm and the UV- visible spectroscopy showed λ\(_{max}\) of 417 nm, which confirms the presence of nanoparticles. The neuroprotective potential of SNPs was evaluated by assessing the antioxidant and cholinesterase inhibitory activity. Metabolomic profiling was performed on methanolic extracts of L. coccineus and M. lutea and resulted in the identification of 12 compounds, then docking was performed to investigate the possible interaction between the identified compounds and human acetylcholinesterase, butyrylcholinesterase, and glutathione transferase receptor, which are associated with the progress of Alzheimer’s disease. Overall our SNPs highlighted its promising potential in terms of anticholinesterase and antioxidant activity as plant-based anti-Alzheimer drug and against oxidative stress. KW - Nanoparticles KW - Silver KW - Alzheimer's disease KW - Glutathione KW - Antioxidants KW - Serine proteases KW - Brain diseases KW - Metabolomics Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-202696 VL - 14 IS - 11 ER - TY - JOUR A1 - Liu, Yi A1 - Maierhofer, Tobias A1 - Rybak, Katarzyna A1 - Sklenar, Jan A1 - Breakspear, Andy A1 - Johnston, Matthew G. A1 - Fliegmann, Judith A1 - Huang, Shouguang A1 - Roelfsema, M. Rob G. A1 - Felix, Georg A1 - Faulkner, Christine A1 - Menke, Frank L.H. A1 - Geiger, Dietmar A1 - Hedrich, Rainer A1 - Robatzek, Silke T1 - Anion channel SLAH3 is a regulatory target of chitin receptor-associated kinase PBL27 in microbial stomatal closure JF - eLife N2 - In plants, antimicrobial immune responses involve the cellular release of anions and are responsible for the closure of stomatal pores. Detection of microbe-associated molecular patterns (MAMPs) by pattern recognition receptors (PRRs) induces currents mediated via slow-type (S-type) anion channels by a yet not understood mechanism. Here, we show that stomatal closure to fungal chitin is conferred by the major PRRs for chitin recognition, LYK5 and CERK1, the receptor-like cytoplasmic kinase PBL27, and the SLAH3 anion channel. PBL27 has the capacity to phosphorylate SLAH3, of which S127 and S189 are required to activate SLAH3. Full activation of the channel entails CERK1, depending on PBL27. Importantly, both S127 and S189 residues of SLAH3 are required for chitin-induced stomatal closure and anti-fungal immunity at the whole leaf level. Our results demonstrate a short signal transduction module from MAMP recognition to anion channel activation, and independent of ABA-induced SLAH3 activation. KW - plants Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-202631 VL - 8 ER - TY - JOUR A1 - Jaślan, Dawid A1 - Dreyer, Ingo A1 - Lu, Jinping A1 - O'Malley, Ronan A1 - Dindas, Julian A1 - Marten, Irene A1 - Hedrich, Rainer T1 - Voltage-dependent gating of SV channel TPC1 confers vacuole excitability JF - Nature Communications N2 - In contrast to the plasma membrane, the vacuole membrane has not yet been associated with electrical excitation of plants. Here, we show that mesophyll vacuoles from Arabidopsis sense and control the membrane potential essentially via the K\(^+\)-permeable TPC1 and TPK channels. Electrical stimuli elicit transient depolarization of the vacuole membrane that can last for seconds. Electrical excitability is suppressed by increased vacuolar Ca\(^{2+}\) levels. In comparison to wild type, vacuoles from the fou2 mutant, harboring TPC1 channels insensitive to luminal Ca\(^{2+}\), can be excited fully by even weak electrical stimuli. The TPC1-loss-of-function mutant tpc1-2 does not respond to electrical stimulation at all, and the loss of TPK1/TPK3-mediated K\(^{+}\) transport affects the duration of TPC1-dependent membrane depolarization. In combination with mathematical modeling, these results show that the vacuolar K\(^+\)-conducting TPC1 and TPK1/TPK3 channels act in concert to provide for Ca\(^{2+}\)- and voltage-induced electrical excitability to the central organelle of plant cells. KW - Biophysics KW - Plant signalling Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-202029 VL - 10 ER - TY - JOUR A1 - Staiger, Simona A1 - Seufert, Pascal A1 - Arand, Katja A1 - Burghardt, Markus A1 - Popp, Christian A1 - Riederer, Markus T1 - The permeation barrier of plant cuticles: uptake of active ingredients is limited by very long-chain aliphatic rather than cyclic wax compounds JF - Pest Management Science N2 - BACKGROUND: The barrier to diffusion of organic solutes across the plant cuticle is composed of waxes consisting of very long-chain aliphatic (VLCA) and, to varying degrees, cyclic compounds like pentacyclic triterpenoids. The roles of both fractions in controlling cuticular penetration by organic solutes, e.g. the active ingredients (AI) of pesticides, are unknown to date. We studied thepermeabilityof isolated leaf cuticularmembranes from Garcinia xanthochymus andPrunus laurocerasus for lipophilic azoxystrobin and theobromine as model compounds for hydrophilic AIs. RESULTS: The wax of P. laurocerasus consists of VLCA (12%) and cyclic compounds (88%), whereas VLCAs make up 97% of the wax of G. xanthochymus.We showthat treating isolated cuticles with methanol almost quantitatively releases the cyclic fraction while leaving the VLCA fraction essentially intact. All VLCAs were subsequently removed using chloroform. In both species, the permeance of the two model compounds did not change significantly after methanol treatment, whereas chloroform extraction had a large effect on organic solute permeability. CONCLUSION: The VLCA wax fractionmakes up the permeability barrier for organic solutes, whereas cyclic compounds even in high amounts have a negligible role. This is of significance when optimizing the foliar uptake of pesticides. KW - cuticular permeability KW - active ingredients KW - very long-chain aliphatic compounds KW - cyclic compounds KW - pesicicles Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-204778 VL - 75 IS - 12 ER - TY - JOUR A1 - Zhang, Yonghong A1 - Zheng, Lanlan A1 - Zheng, Yan A1 - Zhou, Chao A1 - Huang, Ping A1 - Xiao, Xiao A1 - Zhao, Yongheng A1 - Hao, Xincai A1 - Hu, Zhubing A1 - Chen, Qinhua A1 - Li, Hongliang A1 - Wang, Xuanbin A1 - Fukushima, Kenji A1 - Wang, Guodong A1 - Li, Chen T1 - Assembly and Annotation of a Draft Genome of the Medicinal Plant Polygonum cuspidatum JF - Frontiers in Plant Science N2 - Polygonum cuspidatum (Japanese knotweed, also known as Huzhang in Chinese), a plant that produces bioactive components such as stilbenes and quinones, has long been recognized as important in traditional Chinese herbal medicine. To better understand the biological features of this plant and to gain genetic insight into the biosynthesis of its natural products, we assembled a draft genome of P. cuspidatum using Illumina sequencing technology. The draft genome is ca. 2.56 Gb long, with 71.54% of the genome annotated as transposable elements. Integrated gene prediction suggested that the P. cuspidatum genome encodes 55,075 functional genes, including 6,776 gene families that are conserved in the five eudicot species examined and 2,386 that are unique to P. cuspidatum. Among the functional genes identified, 4,753 are predicted to encode transcription factors. We traced the gene duplication history of P. cuspidatum and determined that it has undergone two whole-genome duplication events about 65 and 6.6 million years ago. Roots are considered the primary medicinal tissue, and transcriptome analysis identified 2,173 genes that were expressed at higher levels in roots compared to aboveground tissues. Detailed phylogenetic analysis demonstrated expansion of the gene family encoding stilbene synthase and chalcone synthase enzymes in the phenylpropanoid metabolic pathway, which is associated with the biosynthesis of resveratrol, a pharmacologically important stilbene. Analysis of the draft genome identified 7 abscisic acid and water deficit stress-induced protein-coding genes and 14 cysteine-rich transmembrane module genes predicted to be involved in stress responses. The draft de novo genome assembly produced in this study represents a valuable resource for the molecular characterization of medicinal compounds in P. cuspidatum, the improvement of this important medicinal plant, and the exploration of its abiotic stress resistance. KW - genome assembly KW - resveratrol biosynthesis KW - whole-genome duplication KW - medicinal plant KW - stress tolerance KW - Polygonum cuspidatum Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-189279 SN - 1664-462X VL - 10 ER - TY - JOUR A1 - Raheem, Dotsha J. A1 - Tawfike, Ahmed F. A1 - Abdelmohsen, Usama R. A1 - Edrada-Ebel, RuAngelie A1 - Fitzsimmons-Thoss, Vera T1 - Application of metabolomics and molecular networking in investigating the chemical profile and antitrypanosomal activity of British bluebells (\(Hyacinthoides\) \(non-scripta\)) JF - Scientific Reports N2 - Bulb, leaf, scape and flower samples of British bluebells (Hyacinthoides non-scripta) were collected regularly for one growth period. Methanolic extracts of freeze-dried and ground samples showed antitrypanosomal activity, giving more than 50% inhibition, for 20 out of 41 samples. High-resolution mass spectrometry was used in the dereplication of the methanolic extracts of the different plant parts. The results revealed differences in the chemical profile with bulb samples being distinctly different from all aerial parts. High molecular weight metabolites were more abundant in the flowers, shoots and leaves compared to smaller molecular weight ones in the bulbs. The anti-trypanosomal activity of the extracts was linked to the accumulation of high molecular weight compounds, which were matched with saponin glycosides, while triterpenoids and steroids occurred in the inactive extracts. Dereplication studies were employed to identify the significant metabolites via chemotaxonomic filtration and considering their previously reported bioactivities. Molecular networking was implemented to look for similarities in fragmentation patterns between the isolated saponin glycoside at m/z 1445.64 [M + formic-H](-) equivalent to C64H104O33 and the putatively found active metabolite at m/z 1283.58 [M + formic-H](-) corresponding to scillanoside L-1. A combination of metabolomics and bioactivity-guided approaches resulted in the isolation of a norlanostane-type saponin glycoside with antitrypanosoma I activity of 98.9% inhibition at 20 mu M. KW - Drug discovery KW - Metabolomics Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-224935 VL - 9 ER - TY - JOUR A1 - Hupp, Sabrina A1 - Rosenkranz, Maaria A1 - Bonfig, Katharina A1 - Pandey, Chandana A1 - Roitsch, Thomas T1 - Noninvasive Phenotyping of Plant–Pathogen Interaction: Consecutive In Situ Imaging of Fluorescing Pseudomonas syringae, Plant Phenolic Fluorescence, and Chlorophyll Fluorescence in Arabidopsis Leaves JF - Frontiers in Plant Science N2 - Plant–pathogen interactions have been widely studied, but mostly from the site of the plant secondary defense. Less is known about the effects of pathogen infection on plant primary metabolism. The possibility to transform a fluorescing protein into prokaryotes is a promising phenotyping tool to follow a bacterial infection in plants in a noninvasive manner. In the present study, virulent and avirulent Pseudomonas syringae strains were transformed with green fluorescent protein (GFP) to follow the spread of bacteria in vivo by imaging Pulse-Amplitude-Modulation (PAM) fluorescence and conventional binocular microscopy. The combination of various wavelengths and filters allowed simultaneous detection of GFP-transformed bacteria, PAM chlorophyll fluorescence, and phenolic fluorescence from pathogen-infected plant leaves. The results show that fluorescence imaging allows spatiotemporal monitoring of pathogen spread as well as phenolic and chlorophyll fluorescence in situ, thus providing a novel means to study complex plant–pathogen interactions and relate the responses of primary and secondary metabolism to pathogen spread and multiplication. The study establishes a deeper understanding of imaging data and their implementation into disease screening. KW - green fluorescence protein (GFP) KW - plant–pathogen interaction KW - imaging PAM KW - chlorophyll fluorescence imaging KW - phenolic compounds Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-189425 SN - 1664-462X VL - 10 IS - 1239 ER - TY - JOUR A1 - Keller, Alexander A1 - Brandel, Annette A1 - Becker, Mira C. A1 - Balles, Rebecca A1 - Abdelmohsen, Usama Ramadan A1 - Ankenbrand, Markus J. A1 - Sickel, Wiebke T1 - Wild bees and their nests host Paenibacillus bacteria with functional potential of avail JF - Microbiome N2 - Background: In previous studies, the gram-positive firmicute genus Paenibacillus was found with significant abundances in nests of wild solitary bees. Paenibacillus larvae is well-known for beekeepers as a severe pathogen causing the fatal honey bee disease American foulbrood, and other members of the genus are either secondary invaders of European foulbrood or considered a threat to honey bees. We thus investigated whether Paenibacillus is a common bacterium associated with various wild bees and hence poses a latent threat to honey bees visiting the same flowers. Results: We collected 202 samples from 82 individuals or nests of 13 bee species at the same location and screened each for Paenibacillus using high-throughput sequencing-based 16S metabarcoding. We then isolated the identified strain Paenibacillus MBD-MB06 from a solitary bee nest and sequenced its genome. We did find conserved toxin genes and such encoding for chitin-binding proteins, yet none specifically related to foulbrood virulence or chitinases. Phylogenomic analysis revealed a closer relationship to strains of root-associated Paenibacillus rather than strains causing foulbrood or other accompanying diseases. We found anti-microbial evidence within the genome, confirmed by experimental bioassays with strong growth inhibition of selected fungi as well as gram-positive and gram-negative bacteria. Conclusions: The isolated wild bee associate Paenibacillus MBD-MB06 is a common, but irregularly occurring part of wild bee microbiomes, present on adult body surfaces and guts and within nests especially in megachilids. It was phylogenetically and functionally distinct from harmful members causing honey bee colony diseases, although it shared few conserved proteins putatively toxic to insects that might indicate ancestral predisposition for the evolution of insect pathogens within the group. By contrast, our strain showed anti-microbial capabilities and the genome further indicates abilities for chitin-binding and biofilm-forming, suggesting it is likely a useful associate to avoid fungal penetration of the bee cuticula and a beneficial inhabitant of nests to repress fungal threats in humid and nutrient-rich environments of wild bee nests. KW - 16S metabarcoding KW - American foulbrood KW - anti-microbial activit KW - bacterial genomics KW - bioassays KW - European foulbrood KW - Paenibacterin KW - phylogenomics KW - bee disease KW - pathogen vector Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-177554 VL - 6 IS - 229 ER - TY - JOUR A1 - Tian, Yuehui A1 - Gao, Shiqiang A1 - von der Heyde, Eva Laura A1 - Hallmann, Armin A1 - Nagel, Georg T1 - Two-component cyclase opsins of green algae are ATP-dependent and light-inhibited guanylyl cyclases JF - BMC Biology N2 - Background: The green algae Chlamydomonas reinhardtii and Volvox carteri are important models for studying light perception and response, expressing many different photoreceptors. More than 10 opsins were reported in C. reinhardtii, yet only two—the channelrhodopsins—were functionally characterized. Characterization of new opsins would help to understand the green algae photobiology and to develop new tools for optogenetics. Results: Here we report the characterization of a novel opsin family from these green algae: light-inhibited guanylyl cyclases regulated through a two-component-like phosphoryl transfer, called “two-component cyclase opsins” (2c-Cyclops). We prove the existence of such opsins in C. reinhardtii and V. carteri and show that they have cytosolic N- and C-termini, implying an eight-transmembrane helix structure. We also demonstrate that cGMP production is both light-inhibited and ATP-dependent. The cyclase activity of Cr2c-Cyclop1 is kept functional by the ongoing phosphorylation and phosphoryl transfer from the histidine kinase to the response regulator in the dark, proven by mutagenesis. Absorption of a photon inhibits the cyclase activity, most likely by inhibiting the phosphoryl transfer. Overexpression of Vc2c-Cyclop1 protein in V. carteri leads to significantly increased cGMP levels, demonstrating guanylyl cyclase activity of Vc2c-Cyclop1 in vivo. Live cell imaging of YFP-tagged Vc2c-Cyclop1 in V. carteri revealed a development-dependent, layer-like structure at the immediate periphery of the nucleus and intense spots in the cell periphery. Conclusions: Cr2c-Cyclop1 and Vc2c-Cyclop1 are light-inhibited and ATP-dependent guanylyl cyclases with an unusual eight-transmembrane helix structure of the type I opsin domain which we propose to classify as type Ib, in contrast to the 7 TM type Ia opsins. Overexpression of Vc2c-Cyclop1 protein in V. carteri led to a significant increase of cGMP, demonstrating enzyme functionality in the organism of origin. Fluorescent live cell imaging revealed that Vc2c-Cyclop1 is located in the periphery of the nucleus and in confined areas at the cell periphery. KW - chlamydomonas reinhardtii KW - volvox carteri KW - two-component system KW - chlamyopsin KW - optogenetics Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-177516 VL - 16 IS - 144 ER - TY - JOUR A1 - Scheib, Ulrike A1 - Broser, Matthias A1 - Constantin, Oana M. A1 - Yang, Shang A1 - Gao, Shiqiang A1 - Mukherjee, Shatanik A1 - Stehfest, Katja A1 - Nagel, Georg A1 - Gee, Christine E. A1 - Hegemann, Peter T1 - Rhodopsin-cyclases for photocontrol of cGMP/cAMP and 2.3 Å structure of the adenylyl cyclase domain JF - Nature Communications N2 - The cyclic nucleotides cAMP and cGMP are important second messengers that orchestrate fundamental cellular responses. Here, we present the characterization of the rhodopsinguanylyl cyclase from Catenaria anguillulae (CaRhGC), which produces cGMP in response to green light with a light to dark activity ratio > 1000. After light excitation the putative signaling state forms with tau = 31 ms and decays with tau = 570 ms. Mutations (up to 6) within the nucleotide binding site generate rhodopsin-adenylyl cyclases (CaRhACs) of which the double mutated YFP-CaRhAC (E497K/C566D) is the most suitable for rapid cAMP production in neurons. Furthermore, the crystal structure of the ligand-bound AC domain (2.25 angstrom) reveals detailed information about the nucleotide binding mode within this recently discovered class of enzyme rhodopsin. Both YFP-CaRhGC and YFP-CaRhAC are favorable optogenetic tools for non-invasive, cell-selective, and spatio-temporally precise modulation of cAMP/cGMP with light. KW - Enzymes KW - Molecular biophysics KW - Molecular neuroscience KW - X-ray crystallography Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-228517 VL - 9 ER - TY - JOUR A1 - Abdelhafez, Omnia Hesham A1 - Fawzy, Michael Atef A1 - Fahim, John Refaat A1 - Desoukey, Samar Yehia A1 - Krischke, Markus A1 - Mueller, Martin J. A1 - Abdelmohsen, Usama Ramadan T1 - Hepatoprotective potential of Malvaviscus arboreus against carbon tetrachloride-induced liver injury in rats JF - PLoS ONE N2 - Malvaviscus arboreus Cav. is a medicinal plant belonging to family Malvaceae with both ethnomedical and culinary value; however, its phytochemical and biological profiles have been scarcely studied. Accordingly, this work was designed to explore the chemical composition and the hepatoprotective potential of M. arboreus against carbon tetrachloride (CCl\(_4\))-induced hepatotoxicity. The total extract of the aerial parts and its derived fractions (petroleum ether, dichloromethane, ethyl acetate, and aqueous) were orally administered to rats for six consecutive days, followed by injection of CCl\(_4\) (1:1 v/v, in olive oil, 1.5 ml/kg, i.p.) on the next day. Results showed that the ethyl acetate and dichloromethane fractions significantly alleviated liver injury in rats as indicated by the reduced levels of alanine transaminase (ALT), aspartate transaminase (AST), alkaline phosphatase (ALP), total bilirubin (TB), and malondialdehyde (MDA), along with enhancement of the total antioxidant capacities of their livers, with the maximum effects were recorded by the ethyl acetate fraction. Moreover, the protective actions of both fractions were comparable to those of silymarin (100 mg/kg), and have been also substantiated by histopathological evaluations. On the other hand, liquid chromatography-high resolution electrospray ionization mass spectrometry (LC‒HR‒ESI‒MS) metabolomic profiling of the crude extract of M. arboreus aerial parts showed the presence of a variety of phytochemicals, mostly phenolics, whereas the detailed chemical analysis of the most active fraction (i.e. ethyl acetate) resulted in the isolation and identification of six compounds for the first time in the genus, comprising four phenolic acids; β-resorcylic, caffeic, protocatechuic, and 4-hydroxyphenylacetic acids, in addition to two flavonoids; trifolin and astragalin. Such phenolic principles, together with their probable synergistic antioxidant and liver-protecting properties, seem to contribute to the observed hepatoprotective potential of M. arboreus. KW - high performance liquid chromatography KW - phenols KW - phytochemicals KW - antioxidants KW - metabolomics KW - medicinal plants KW - Egypt KW - xenobiotic metabolism KW - Malvaviscus arboreus Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-177243 VL - 13 IS - 8 ER - TY - JOUR A1 - Rostás, Michael A1 - Bollmann, Felix A1 - Saville, David A1 - Riedel, Michael T1 - Ants contribute to pollination but not to reproduction in a rare calcareous grassland forb JF - PeerJ N2 - The number of plants pollinated by ants is surprisingly low given the abundance of ants and the fact that they are common visitors of angiosperms. Generally ants are considered as nectar robbers that do not provide pollination service. We studied the pollination system of the endangered dry grassland forb Euphorbia seguieriana and found two ant species to be the most frequent visitors of its flowers. Workers of Formica cunicularia carried five times more pollen than smaller Tapinoma erraticum individuals, but significantly more viable pollen was recovered from the latter. Overall, the viability of pollen on ant cuticles was significantly lower (p < 0.001)-presumably an antibiotic effect of the metapleural gland secretion. A marking experiment suggested that ants were unlikely to facilitate outcrossing as workers repeatedly returned to the same individual plant. In open pollinated plants and when access was given exclusively to flying insects, fruit set was nearly 100%. In plants visited by ants only, roughly one third of flowers set fruit, and almost none set fruit when all insects were excluded. The germination rate of seeds from flowers pollinated by flying insects was 31 +/- 7% in contrast to 1 +/- 1% resulting from ant pollination. We conclude that inbreeding depression may be responsible for the very low germination rate in ant pollinated flowers and that ants, although the most frequent visitors, play a negligible or even deleterious role in the reproduction of E. seguieriana. Our study reiterates the need to investigate plant fitness effects beyond seed set in order to confirm ant-plant mutualisms. KW - Ants KW - Breeding system KW - Geitonogamy KW - Germination KW - Inbreeding depression KW - Metapleural gland KW - Siberian spurge KW - Foraging behaviour KW - Pollen KW - Ecology KW - Entomology Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-227053 VL - 6 ER - TY - JOUR A1 - Hürter, Anna-Lena A1 - Fort, Sébastian A1 - Cottaz, Sylvain A1 - Hedrich, Rainer A1 - Geiger, Dietmar A1 - Roelfsema, M. Rob G. T1 - Mycorrhizal lipochitinoligosaccharides (LCOs) depolarize root hairs of Medicago truncatula JF - PLoS ONE N2 - Arbuscular Mycorrhiza and Root Nodule Symbiosis are symbiotic interactions with a high benefit for plant growth and crop production. Thus, it is of great interest to understand the developmental process of these symbioses in detail. We analysed very early symbiotic responses of Medicago truncatula root hair cells, by stimulation with lipochitinoligosaccharides specific for the induction of nodules (Nod-LCOs), or the interaction with mycorrhiza (Myc-LCOs). Intracellular micro electrodes were used, in combination with Ca\(^{2+}\) sensitive reporter dyes, to study the relations between cytosolic Ca\(^{2+}\) signals and membrane potential changes. We found that sulfated Myc- as well as Nod-LCOs initiate a membrane depolarization, which depends on the chemical composition of these signaling molecules, as well as the genotype of the plants that were studied. A successive application of sulfated Myc-LCOs and Nod-LCOs resulted only in a single transient depolarization, indicating that Myc-LCOs can repress plasma membrane responses to Nod-LCOs. In contrast to current models, the Nod-LCO-induced depolarization precedes changes in the cytosolic Ca\(^{2+}\) level of root hair cells. The Nod-LCO induced membrane depolarization thus is most likely independent of cytosolic Ca\(^{2+}\) signals and nuclear Ca\(^{2+}\) spiking. KW - depolarization KW - Medicago truncatula KW - lipochitinoligosaccharides Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-176841 VL - 13 IS - 5 ER - TY - JOUR A1 - Schäfer, Nadine A1 - Friedrich, Maximilian A1 - Jørgensen, Morten Egevang A1 - Kollert, Sina A1 - Koepsell, Hermann A1 - Wischmeyer, Erhard A1 - Lesch, Klaus-Peter A1 - Geiger, Dietmar A1 - Döring, Frank T1 - Functional analysis of a triplet deletion in the gene encoding the sodium glucose transporter 3, a potential risk factor for ADHD JF - PLoS ONE N2 - Sodium-glucose transporters (SGLT) belong to the solute carrier 5 family, which is characterized by sodium dependent transport of sugars and other solutes. In contrast, the human SGLT3 (hSGLT3) isoform, encoded by SLC5A4, acts as a glucose sensor that does not transport sugar but induces membrane depolarization by Na\(^{+}\) currents upon ligand binding. Whole-exome sequencing (WES) of several extended pedigrees with high density of attention-deficit/hyperactivity disorder (ADHD) identified a triplet ATG deletion in SLC5A4 leading to a single amino acid loss (ΔM500) in the hSGLT3 protein imperfectly co-segregating with the clinical phenotype of ADHD. Since mutations in homologous domains of hSGLT1 and hSGLT2 were found to affect intestinal and renal function, respectively, we analyzed the functional properties of hSGLT3[wt] and [ΔM500] by voltage clamp and current clamp recordings from cRNA-injected Xenopus laevis oocytes. The cation conductance of hSGLT3[wt] was activated by application of glucose or the specific agonist 1-desoxynojirimycin (DNJ) as revealed by inward currents in the voltage clamp configuration and cell depolarization in the current clamp mode. Almost no currents and changes in membrane potential were observed when glucose or DNJ were applied to hSGLT3[ΔM500]-injected oocytes, demonstrating a loss of function by this amino acid deletion in hSGLT3. To monitor membrane targeting of wt and mutant hSGLT3, fusion constructs with YFP were generated, heterologously expressed in Xenopus laevis oocytes and analyzed for membrane fluorescence by confocal microscopy. In comparison to hSGLT3[wt] the fluorescent signal of mutant [ΔM500] was reduced by 43% indicating that the mutant phenotype might mainly result from inaccurate membrane targeting. As revealed by homology modeling, residue M500 is located in TM11 suggesting that in addition to the core structure (TM1-TM10) of the transporter, the surrounding TMs are equally crucial for transport/sensor function. In conclusion, our findings indicate that the deletion [ΔM500] in hSGLT3 inhibits membrane targeting and thus largely disrupts glucose-induced sodium conductance, which may, in interaction with other ADHD risk-related gene variants, influence the risk for ADHD in deletion carriers. KW - Xenopus laevis oocytes KW - ADHD KW - glucose KW - cell membranes KW - membrane proteins KW - membrane potential KW - crystal structure KW - amino acid analysis Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-176495 VL - 13 IS - 10 ER - TY - JOUR A1 - Beck, Sebastian A1 - Yu-Strzelczyk, Jing A1 - Pauls, Dennis A1 - Constantin, Oana M. A1 - Gee, Christine E. A1 - Ehmann, Nadine A1 - Kittel, Robert J. A1 - Nagel, Georg A1 - Gao, Shiqiang T1 - Synthetic light-activated ion channels for optogenetic activation and inhibition JF - Frontiers in Neuroscience N2 - Optogenetic manipulation of cells or living organisms became widely used in neuroscience following the introduction of the light-gated ion channel channelrhodopsin-2 (ChR2). ChR2 is a non-selective cation channel, ideally suited to depolarize and evoke action potentials in neurons. However, its calcium (Ca2\(^{2+}\)) permeability and single channel conductance are low and for some applications longer-lasting increases in intracellular Ca\(^{2+}\) might be desirable. Moreover, there is need for an efficient light-gated potassium (K\(^{+}\)) channel that can rapidly inhibit spiking in targeted neurons. Considering the importance of Ca\(^{2+}\) and K\(^{+}\) in cell physiology, light-activated Ca\(^{2+}\)-permeant and K\(^{+}\)-specific channels would be welcome additions to the optogenetic toolbox. Here we describe the engineering of novel light-gated Ca\(^{2+}\)-permeant and K\(^{+}\)-specific channels by fusing a bacterial photoactivated adenylyl cyclase to cyclic nucleotide-gated channels with high permeability for Ca\(^{2+}\) or for K\(^{+}\), respectively. Optimized fusion constructs showed strong light-gated conductance in Xenopus laevis oocytes and in rat hippocampal neurons. These constructs could also be used to control the motility of Drosophila melanogaster larvae, when expressed in motoneurons. Illumination led to body contraction when motoneurons expressed the light-sensitive Ca\(^{2+}\)-permeant channel, and to body extension when expressing the light-sensitive K\(^{+}\) channel, both effectively and reversibly paralyzing the larvae. Further optimization of these constructs will be required for application in adult flies since both constructs led to eclosion failure when expressed in motoneurons. KW - optogenetics KW - calcium KW - potassium KW - bPAC KW - CNG channel KW - cAMP KW - Drosophila melanogaster motoneuron KW - rat hippocampal neurons Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-177520 VL - 12 IS - 643 ER - TY - JOUR A1 - Lagler, Charlotte A1 - El-Mesery, Mohamed A1 - Kübler, Alexander Christian A1 - Müller-Richter, Urs Dietmar Achim A1 - Stühmer, Thorsten A1 - Nickel, Joachim A1 - Müller, Thomas Dieter A1 - Wajant, Harald A1 - Seher, Axel T1 - The anti-myeloma activity of bone morphogenetic protein 2 predominantly relies on the induction of growth arrest and is apoptosis-independent JF - PLoS ONE N2 - Multiple myeloma (MM), a malignancy of the bone marrow, is characterized by a pathological increase in antibody-producing plasma cells and an increase in immunoglobulins (plasmacytosis). In recent years, bone morphogenetic proteins (BMPs) have been reported to be activators of apoptotic cell death in neoplastic B cells in MM. Here, we use bone morphogenetic protein 2 (BMP2) to show that the "apoptotic" effect of BMPs on human neoplastic B cells is dominated by anti-proliferative activities and cell cycle arrest and is apoptosis-independent. The anti-proliferative effect of BMP2 was analysed in the human cell lines KMS12-BM and L363 using WST-1 and a Coulter counter and was confirmed using CytoTox assays with established inhibitors of programmed cell death (zVAD-fmk and necrostatin-1). Furthermore, apoptotic activity was compared in both cell lines employing western blot analysis for caspase 3 and 8 in cells treated with BMP2 and FasL. Additionally, expression profiles of marker genes of different cell death pathways were analysed in both cell lines after stimulation with BMP2 for 48h using an RT-PCR-based array. In our experiments we observed that there was rather no reduction in absolute cell number, but cells stopped proliferating following treatment with BMP2 instead. The time frame (48–72 h) after BMP2 treatment at which a reduction in cell number is detectable is too long to indicate a directly BMP2-triggered apoptosis. Moreover, in comparison to robust apoptosis induced by the approved apoptotic factor FasL, BMP2 only marginally induced cell death. Consistently, neither the known inhibitor of apoptotic cell death zVAD-fmk nor the necroptosis inhibitor necrostatin-1 was able to rescue myeloma cell growth in the presence of BMP2. KW - apoptosis KW - gene expression KW - necrotic cell death KW - multiple myeloma KW - cell metabolism KW - cell cycle and cell division KW - B cells Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-158993 VL - 12 IS - 10 ER - TY - JOUR A1 - Cheng, Cheng A1 - Othman, Eman M. A1 - Stopper, Helga A1 - Edrada-Ebel, RuAngelie A1 - Hentschel, Ute A1 - Abdelmohsen, Usama Ramadan T1 - Isolation of petrocidin A, a new cytotoxic cyclic dipeptide from the marine sponge-derived bacterium \(Streptomyces\) sp. SBT348 JF - Marine Drugs N2 - A new cyclic dipeptide, petrocidin A (\(\textbf{1}\)), along with three known compounds—2,3-dihydroxybenzoic acid (\(\textbf{2}\)), 2,3-dihydroxybenzamide (\(\textbf{3}\)), and maltol (\(\textbf{4}\))—were isolated from the solid culture of \(Streptomyces\) sp. SBT348. The strain \(Streptomyces\) sp. SBT348 had been prioritized in a strain collection of 64 sponge-associated actinomycetes based on its distinct metabolomic profile using liquid chromatography/high-resolution mass spectrometry (LC-HRMS) and nuclear magnetic resonance (NMR). The absolute configuration of all α-amino acids was determined by HPLC analysis after derivatization with Marfey’s reagent and comparison with commercially available reference amino acids. Structure elucidation was pursued in the presented study by mass spectrometry and NMR spectral data. Petrocidin A (\(\textbf{1}\)) and 2,3-dihydroxybenzamide (\(\textbf{3}\)) exhibited significant cytotoxicity towards the human promyelocytic HL-60 and the human colon adenocarcinoma HT-29 cell lines. These results demonstrated the potential of sponge-associated actinomycetes for the discovery of novel and pharmacologically active natural products. KW - biology KW - sponges KW - actinomycetes KW - streptomyces KW - cyclic dipeptide KW - cytotoxic Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-172644 VL - 15 IS - 12 ER - TY - JOUR A1 - Salker, Madhuri S. A1 - Singh, Yogesh A1 - Zeng, Ni A1 - Chen, Hong A1 - Zhang, Shaqiu A1 - Umbach, Anja T. A1 - Fakhri, Hajar A1 - Kohlhofer, Ursula A1 - Quintanilla-Martinez, Leticia A1 - Durairaj, Ruban R. Peter A1 - Barros, Flavio S. V. A1 - Vrljicak, Pavle A1 - Ott, Sascha A1 - Brucker, Sara Y. A1 - Wallwiener, Diethelm A1 - Madunić, Ivana Vrhovac A1 - Breljak, Davorka A1 - Sabolić, Ivan A1 - Koepsell, Hermann A1 - Brosens, Jan J. A1 - Lang, Florian T1 - Loss of endometrial sodium glucose cotransporter SGLT1 is detrimental to embryo survival and fetal growth in pregnancy JF - Scientific Reports N2 - Embryo implantation requires a hospitable uterine environment. A key metabolic change that occurs during the peri-implantation period, and throughout early pregnancy, is the rise in endometrial glycogen content. Glycogen accumulation requires prior cellular uptake of glucose. Here we show that both human and murine endometrial epithelial cells express the high affinity Na\(^+\)-coupled glucose carrier SGLT1. Ussing chamber experiments revealed electrogenic glucose transport across the endometrium in wild type (\(Slc5a1^{+/+}\)) but not in SGLT1 defcient (\(Slc5a1^{−/−}\)) mice. Endometrial glycogen content, litter size and weight of offspring at birth were signifcantly lower in \(Slc5a1^{−/−}\) mice. In humans, \(SLC5A1\) expression was upregulated upon decidualization of primary endometrial stromal cells. Endometrial \(SLC5A1\) expression during the implantation window was attenuated in patients with recurrent pregnancy loss when compared with control subjects. Our fndings reveal a novel mechanism establishing adequate endometrial glycogen stores for pregnancy. Disruption of this histiotrophic pathway leads to adverse pregnancy outcome. KW - biology KW - embryology KW - intrauterine growth KW - paediatric research Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-173814 VL - 7 ER - TY - JOUR A1 - Balasubramanian, Srikkanth A1 - Othman, Eman M. A1 - Kampik, Daniel A1 - Stopper, Helga A1 - Hentschel, Ute A1 - Ziebuhr, Wilma A1 - Oelschlaeger, Tobias A. A1 - Abdelmohsen, Usama R. T1 - Marine sponge-derived Streptomyces sp SBT343 extract inhibits staphylococcal biofilm formation JF - Frontiers in Microbiology N2 - Staphylococcus epidermidis and Staphylococcus aureus are opportunistic pathogens that cause nosocomial and chronic biofilm-associated infections. Indwelling medical devices and contact lenses are ideal ecological niches for formation of staphylococcal biofilms. Bacteria within biofilms are known to display reduced susceptibilities to antimicrobials and are protected from the host immune system. High rates of acquired antibiotic resistances in staphylococci and other biofilm-forming bacteria further hamper treatment options and highlight the need for new anti-biofilm strategies. Here, we aimed to evaluate the potential of marine sponge-derived actinomycetes in inhibiting biofilm formation of several strains of S. epidermidis, S. aureus, and Pseudomonas aeruginosa. Results from in vitro biofilm-formation assays, as well as scanning electron and confocal microscopy, revealed that an organic extract derived from the marine sponge-associated bacterium Streptomyces sp. SBT343 significantly inhibited staphylococcal biofilm formation on polystyrene, glass and contact lens surfaces, without affecting bacterial growth. The extract also displayed similar antagonistic effects towards the biofilm formation of other S. epidermidis and S. aureus strains tested but had no inhibitory effects towards Pseudomonas biofilms. Interestingly the extract, at lower effective concentrations, did not exhibit cytotoxic effects on mouse fibroblast, macrophage and human corneal epithelial cell lines. Chemical analysis by High Resolution Fourier Transform Mass Spectrometry (HRMS) of the Streptomyces sp. SBT343 extract proportion revealed its chemical richness and complexity. Preliminary physico-chemical characterization of the extract highlighted the heat-stable and non-proteinaceous nature of the active component(s). The combined data suggest that the Streptomyces sp. SBT343 extract selectively inhibits staphylococcal biofilm formation without interfering with bacterial cell viability. Due to absence of cell toxicity, the extract might represent a good starting material to develop a future remedy to block staphylococcal biofilm formation on contact lenses and thereby to prevent intractable contact lens-mediated ocular infections. KW - medicine KW - marine sponges KW - actinomycetes KW - Streptomyces KW - staphilococci KW - biofilms KW - contact lens Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-171844 VL - 8 ER - TY - JOUR A1 - Van Steenbergen, Anne A1 - Balteau, Magali A1 - Ginion, Audrey A1 - Ferté, Laura A1 - Battault, Sylvain A1 - de Meester de Ravenstein, Christophe A1 - Balligand, Jean-Luc A1 - Daskalopoulos, Evangelos-Panagiotis A1 - Gilon, Patrick A1 - Despa, Florin A1 - Despa, Sanda A1 - Vanoverschelde, Jean-Louis A1 - Horman, Sandrine A1 - Koepsell, Hermann A1 - Berry, Gerard A1 - Hue, Louis A1 - Bertrand, Luc A1 - Beauloye, Christophe T1 - Sodium-myoinositol cotransporter-1, SMIT1, mediates the production of reactive oxygen species induced by hyperglycemia in the heart JF - Scientific Reports N2 - Hyperglycemia (HG) stimulates the production of reactive oxygen species in the heart through activation of NADPH oxidase 2 (NOX2). This production is independent of glucose metabolism but requires sodium/glucose cotransporters (SGLT). Seven SGLT isoforms (SGLT1 to 6 and sodium-myoinositol cotransporter-1, SMIT1) are known, although their expression and function in the heart remain elusive. We investigated these 7 isoforms and found that only SGLT1 and SMIT1 were expressed in mouse, rat and human hearts. In cardiomyocytes, galactose (transported through SGLT1) did not activate NOX2. Accordingly, SGLT1 deficiency did not prevent HG-induced NOX2 activation, ruling it out in the cellular response to HG. In contrast, myo-inositol (transported through SMIT1) reproduced the toxic effects of HG. SMIT1 overexpression exacerbated glucotoxicity and sensitized cardiomyocytes to HG, whereas its deletion prevented HG-induced NOX2 activation. In conclusion, our results show that heart SMIT1 senses HG and triggers NOX2 activation. This could participate in the redox signaling in hyperglycemic heart and contribute to the pathophysiology of diabetic cardiomyopathy. KW - hyperglycemia KW - Sodium-myoinositol cotransporter-1 (SMIT1) KW - glucose metabolism KW - heart KW - NADPH oxidase 2 (NOX2) KW - sodium/glucose cotransporters (SGLT) KW - cardiomyocytes Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-180891 VL - 7 ER - TY - JOUR A1 - Weiste, Christoph A1 - Pedrotti, Lorenzo A1 - Selvanayagam, Jebasingh A1 - Muralidhara, Prathibha A1 - Fröschel, Christian A1 - Novák, Ondřej A1 - Ljung, Karin A1 - Hanson, Johannes A1 - Dröge-Laser, Wolfgang T1 - The Arabidopsis bZIP11 transcription factor links low-energy signalling to auxin-mediated control of primary root growth JF - PLoS Genetics N2 - Plants have to tightly control their energy homeostasis to ensure survival and fitness under constantly changing environmental conditions. Thus, it is stringently required that energy-consuming stress-adaptation and growth-related processes are dynamically tuned according to the prevailing energy availability. The evolutionary conserved SUCROSE NON-FERMENTING1 RELATED KINASES1 (SnRK1) and the downstream group C/S\(_{1}\) basic leucine zipper (bZIP) transcription factors (TFs) are well-characterised central players in plants’ low-energy management. Nevertheless, mechanistic insights into plant growth control under energy deprived conditions remains largely elusive. In this work, we disclose the novel function of the low-energy activated group S\(_{1}\) bZIP11-related TFs as regulators of auxin-mediated primary root growth. Whereas transgenic gain-of-function approaches of these bZIPs interfere with the activity of the root apical meristem and result in root growth repression, root growth of loss-of-function plants show a pronounced insensitivity to low-energy conditions. Based on ensuing molecular and biochemical analyses, we propose a mechanistic model, in which bZIP11-related TFs gain control over the root meristem by directly activating IAA3/SHY2 transcription. IAA3/SHY2 is a pivotal negative regulator of root growth, which has been demonstrated to efficiently repress transcription of major auxin transport facilitators of the PIN-FORMED (PIN) gene family, thereby restricting polar auxin transport to the root tip and in consequence auxin-driven primary root growth. Taken together, our results disclose the central low-energy activated SnRK1-C/S\(_{1}\)-bZIP signalling module as gateway to integrate information on the plant’s energy status into root meristem control, thereby balancing plant growth and cellular energy resources. KW - root growth KW - sucrose KW - auxins KW - meristems KW - regulator genes KW - genetically modified plants KW - gene expression KW - plant growth and development Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-157742 VL - 13 IS - 2 ER - TY - JOUR A1 - Jodeleit, Henrika A1 - Palamides, Pia A1 - Beigel, Florian A1 - Mueller, Thomas A1 - Wolf, Eckhard A1 - Siebeck, Matthias A1 - Gropp, Roswitha T1 - Design and validation of a disease network of inflammatory processes in the NSG-UC mouse model JF - Journal of Translational Medicine N2 - Background: Ulcerative colitis (UC) is a highly progressive inflammatory disease that requires the interaction of epithelial, immune, endothelial and muscle cells and fibroblasts. Previous studies suggested two inflammatory conditions in UC-patients: ‘acute’ and ‘remodeling’ and that the design of a disease network might improve the understanding of the inflammatory processes. The objective of the study was to design and validate a disease network in the NOD-SCID IL2rγ\(^{null}\) (NSG)-UC mouse model to get a better understanding of the inflammatory processes. Methods: Leukocytes were isolated from the spleen of NSG-UC mice and subjected to flow cytometric analysis. RT-PCR and RNAseq analysis were performed from distal parts of the colon. Based on these analyses and the effects of interleukins, chemokines and growth factors described in the literature, a disease network was designed. To validate the disease network the effect of infliximab and pitrakinra was tested in the NSG-UC model. A clinical- and histological score, frequencies of human leukocytes isolated from spleen and mRNA expression levels from distal parts of the colon were determined. Results: Analysis of leukocytes isolated from the spleen of challenged NSG-UC mice corroborated CD64, CD163 and CD1a expressing CD14+ monocytes, CD1a expressing CD11b+ macrophages and HGF, TARC, IFNγ and TGFß1 mRNA as inflammatory markers. The disease network suggested that a proinflammatory condition elicited by IL-17c and lipids and relayed by cytotoxic T-cells, Th17 cells and CD1a expressing macrophages and monocytes. Conversely, the remodeling condition was evoked by IL-34 and TARC and promoted by Th2 cells and M2 monocytes. Mice benefitted from treatment with infliximab as indicated by the histological- and clinical score. As predicted by the disease network infliximab reduced the proinflammatory response by suppressing M1 monocytes and CD1a expressing monocytes and macrophages and decreased levels of IFNγ, TARC and HGF mRNA. As predicted by the disease network inflammation aggravated in the presence of pitrakinra as indicated by the clinical and histological score, elevated frequencies of CD1a expressing macrophages and TNFα and IFNγ mRNA levels. Conclusions: The combination of the disease network and the NSG-UC animal model might be developed into a powerful tool to predict efficacy or in-efficacy and potential mechanistic side effects. KW - Autoimmunity KW - Disease network KW - Inflammatory bowel disease KW - NSG KW - NSG-UC KW - Ulcerative colitis Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-225516 VL - 15 ER - TY - JOUR A1 - Shady, Nourhan Hisham A1 - El-Hossary, Ebaa M. A1 - Fouad, Mostafa A. A1 - Gulder, Tobias A. M. A1 - Kamel, Mohamed Salah A1 - Abdelmohsen, Usama Ramadan T1 - Bioactive natural products of marine sponges from the Genus Hyrtios JF - Molecules N2 - Marine sponges are known as a rich source for novel bioactive compounds with valuable pharmacological potential. One of the most predominant sponge genera is Hyrtios, reported to have various species such as Hyrtios erectus, Hyrtios reticulatus, Hyrtios gumminae, Hyrtios communis, and Hyrtios tubulatus and a number of undescribed species. Members of the genus Hyrtios are a rich source of natural products with diverse and valuable biological activities, represented by different chemical classes including alkaloids, sesterterpenes and sesquiterpenes. This review covers the literature until June 2016, providing a complete survey of all compounds isolated from the genus Hyrtios with their corresponding biological activities whenever applicable. KW - alkaloids KW - bioactive KW - marine natural products KW - marine sponges KW - Hyrtios Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-158227 VL - 22 IS - 5 ER - TY - JOUR A1 - Münch, Miriam A1 - Hsin, Chih-Hsuan A1 - Ferber, Elena A1 - Berger, Susanne A1 - Müller, Martin J. T1 - Reactive electrophilic oxylipins trigger a heat stress-like response through HSFA1 transcription factors JF - Journal of Experimental Botany N2 - Electrophilic oxylipins trigger a heat-shock-like response in the absence of heat through the canonical heat-shock transcription factor A1, thereby helping to cope with stresses associated with protein damage.Abiotic and biotic stresses are often characterized by an induction of reactive electrophile species (RES) such as the jasmonate 12-oxo-phytodienoic acid (OPDA) or the structurally related phytoprostanes. Previously, RES oxylipins have been shown massively to induce heat-shock-response (HSR) genes including HSP101 chaperones. Moreover, jasmonates have been reported to play a role in basal thermotolerance. We show that representative HSR marker genes are strongly induced by RES oxylipins through the four master regulator transcription factors HSFA1a, b, d, and e essential for short-term adaptation to heat stress in Arabidopsis. When compared with Arabidopsis seedlings treated at the optimal acclimation temperature of 37 A degrees C, the exogenous application of RES oxylipins at 20 A degrees C induced a much weaker induction of HSP101 at both the gene and protein expression levels which, however, was not sufficient to confer short-term acquired thermotolerance. Moreover, jasmonate-deficient mutant lines displayed a wild-type-like HSR and were not compromised in acquiring thermotolerance. Hence, the OPDA- and RES oxylipin-induced HSR is not sufficient to protect seedlings from severe heat stress but may help plants to cope better with stresses associated with protein unfolding by inducing a battery of chaperones in the absence of heat. KW - arabidopsis-thaliana KW - shock response KW - gene-expression KW - model KW - acquired thermotolerance KW - 12-oxo-phytodienoic acid KW - thermotolerance KW - plants KW - detoxification KW - acquisition KW - activation KW - heat stress KW - jasmonates KW - phytoprostanes KW - reactive electrophilic species KW - unfolded protein response Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-186766 VL - 67 IS - 21 ER - TY - JOUR A1 - Joensuu, Johanna A1 - Altimir, Nuria A1 - Hakola, Hannele A1 - Rostás, Michael A1 - Raivonen, Maarit A1 - Vestenius, Mika A1 - Aaltonen, Hermanni A1 - Riederer, Markus A1 - Bäck, Jaana T1 - Role of needle surface waxes in dynamic exchange of mono- and sesquiterpenes JF - Atmospheric Chemistry and Physics N2 - Biogenic volatile organic compounds (BVOCs) produced by plants have a major role in atmospheric chemistry. The different physicochemical properties of BVOCs affect their transport within and out of the plant as well as their reactions along the way. Some of these compounds may accumulate in or on the waxy surface layer of conifer needles and participate in chemical reactions on or near the foliage surface. The aim of this work was to determine whether terpenes, a key category of BVOCs produced by trees, can be found on the epicuticles of Scots pine (Pinus sylvestris L.) and, if so, how they compare with the terpenes found in shoot emissions of the same tree. We measured shoot-level emissions of pine seedlings at a remote outdoor location in central Finland and subsequently analysed the needle surface waxes for the same compounds. Both emissions and wax extracts were clearly dominated by monoterpenes, but the proportion of sesquiterpenes was higher in the wax extracts. There were also differences in the terpene spectra of the emissions and the wax extracts. The results, therefore, support the existence of BVOC associated to the epicuticular waxes. We briefly discuss the different pathways for terpenes to reach the needle surfaces and the implications for air chemistry. KW - needle surface waxes KW - biogenic volatile organic compounds KW - Pinus sylvestris L. KW - atmospheric chemistry Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-171324 VL - 16 IS - 12 ER - TY - JOUR A1 - Vendelova, Emilia A1 - de Lima, Jeferson Camargo A1 - Lorenzatto, Karina Rodrigues A1 - Monteiro, Karina Mariante A1 - Mueller, Thomas A1 - Veepaschit, Jyotishman A1 - Grimm, Clemens A1 - Brehm, Klaus A1 - Hrčková, Gabriela A1 - Lutz, Manfred B. A1 - Ferreira, Henrique B. A1 - Nono, Justin Komguep T1 - Proteomic Analysis of Excretory-Secretory Products of Mesocestoides corti Metacestodes Reveals Potential Suppressors of Dendritic Cell Functions JF - PLoS Neglected Tropical Diseases N2 - Accumulating evidences have assigned a central role to parasite-derived proteins in immunomodulation. Here, we report on the proteomic identification and characterization of immunomodulatory excretory-secretory (ES) products from the metacestode larva (tetrathyridium) of the tapeworm Mesocestoides corti (syn. M. vogae). We demonstrate that ES products but not larval homogenates inhibit the stimuli-driven release of the pro-inflammatory, Th1-inducing cytokine IL-12p70 by murine bone marrow-derived dendritic cells (BMDCs). Within the ES fraction, we biochemically narrowed down the immunosuppressive activity to glycoproteins since active components were lipid-free, but sensitive to heat- and carbohydrate-treatment. Finally, using bioassay-guided chromatographic analyses assisted by comparative proteomics of active and inactive fractions of the ES products, we defined a comprehensive list of candidate proteins released by M. corti tetrathyridia as potential suppressors of DC functions. Our study provides a comprehensive library of somatic and ES products and highlight some candidate parasite factors that might drive the subversion of DC functions to facilitate the persistence of M. corti tetrathyridia in their hosts. KW - proteomic analysis KW - excretory-secretory KW - Mesocestoides corti Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-166742 VL - 10 IS - 10 ER - TY - JOUR A1 - Palamides, Pia A1 - Jodeleit, Henrika A1 - Föhlinger, Michael A1 - Beigel, Florian A1 - Herbach, Nadja A1 - Mueller, Thomas A1 - Wolf, Eckhard A1 - Siebeck, Matthias A1 - Gropp, Roswitha T1 - A mouse model for ulcerative colitis based on NOD-scid IL2R gamma(null) mice reconstituted with peripheral blood mononuclear cells from affected individuals JF - Disease Models & Mechanisms N2 - Animal models reflective of ulcerative colitis (UC) remain a major challenge, and yet are crucial to understand mechanisms underlying the onset of disease and inflammatory characteristics of relapses and remission. Mouse models in which colitis-like symptoms are induced through challenge with toxins such as oxazolone, dextran sodium sulfate (DSS) or 2,4,6-trinitrobenzenesulfonic acid (TNBS) have been instrumental in understanding the inflammatory processes of UC. However, these neither reflect the heterogeneous symptoms observed in the UC-affected population nor can they be used to test the efficacy of inhibitors developed against human targets where high sequence and structural similarity of the respective ligands is lacking. In an attempt to overcome these problems, we have developed a mouse model that relies on NOD-scid IL2R γnull mice reconstituted with peripheral blood mononuclear cells derived from UC-affected individuals. Upon challenge with ethanol, mice developed colitis-like symptoms and changes in the colon architecture, characterized by influx of inflammatory cells, edema, crypt loss, crypt abscesses and epithelial hyperplasia, as previously observed in immune-competent mice. TARC, TGFβ1 and HGF expression increased in distal parts of the colon. Analysis of human leucocytes isolated from mouse spleen revealed an increase in frequencies of CD1a+, CD64+, CD163+ and TSLPR+ CD14+ monocytes, and antigen-experienced CD44+ CD4+ and CD8+ T-cells in response to ethanol. Analysis of human leucocytes from the colon of challenged mice identified CD14+ monocytes and CD11b+ monocytes as the predominant populations. Quantitative real-time PCR (RT-PCR) analysis from distal parts of the colon indicated that IFNγ might be one of the cytokines driving inflammation. Treatment with infliximab ameliorated symptoms and pathological manifestations, whereas pitrakinra had no therapeutic benefit. Thus, this model is partially reflective of the human disease and might help to increase the translation of animal and clinical studies. KW - animal models KW - Ulcerative colitis KW - NSG mice KW - Infliximab KW - Pitrakinra Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-164946 VL - 9 ER - TY - JOUR A1 - Walper, Elisabeth A1 - Weiste, Christoph A1 - Mueller, Martin J. A1 - Hamberg, Mats A1 - Dröge-Laser, Wolfgang T1 - Screen Identifying Arabidopsis Transcription Factors Involved in the Response to 9-Lipoxygenase-Derived Oxylipins JF - PLoS One N2 - 13-Lipoxygenase-derived oxylipins, such as jasmonates act as potent signaling molecules in plants. Although experimental evidence supports the impact of oxylipins generated by the 9-Lipoxygenase (9-LOX) pathway in root development and pathogen defense, their signaling function in plants remains largely elusive. Based on the root growth inhibiting properties of the 9-LOX-oxylipin 9-HOT (9-hydroxy-10,12,15-octadecatrienoic acid), we established a screening approach aiming at identifying transcription factors (TFs) involved in signaling and/or metabolism of this oxylipin. Making use of the AtTORF-Ex (Arabidopsis thaliana Transcription Factor Open Reading Frame Expression) collection of plant lines overexpressing TF genes, we screened for those TFs which restore root growth on 9-HOT. Out of 6,000 lines, eight TFs were recovered at least three times and were therefore selected for detailed analysis. Overexpression of the basic leucine Zipper (bZIP) TF TGA5 and its target, the monoxygenase CYP81D11 reduced the effect of added 9-HOT, presumably due to activation of a detoxification pathway. The highly related ETHYLENE RESPONSE FACTORs ERF106 and ERF107 induce a broad detoxification response towards 9-LOX-oxylipins and xenobiotic compounds. From a set of 18 related group S-bZIP factors isolated in the screen, bZIP11 is known to participate in auxin-mediated root growth and may connect oxylipins to root meristem function. The TF candidates isolated in this screen provide starting points for further attempts to dissect putative signaling pathways involving 9-LOX-derived oxylipins. KW - Jasmonic acid KW - root growth KW - arabidopsis thaliana KW - detoxification KW - seedlings KW - stress signaling cascade KW - hyperexpression techniques KW - ranscription factors Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-146857 VL - 11 IS - 4 ER - TY - JOUR A1 - Zhu, Min A1 - Shabala, Lana A1 - Cuin, Tracey A. A1 - Huang, Xin A1 - Zhou, Meixue A1 - Munns, Rana A1 - Shabala, Sergey T1 - Nax loci affect SOS1-like Na\(^+\)/H\(^+\) exchanger expression and activity in wheat JF - Journal of Experimental Botany N2 - Salinity stress tolerance in durum wheat is strongly associated with a plant's ability to control Na\(^+\) delivery to the shoot. Two loci, termed Nax1 and Nax2, were recently identified as being critical for this process and the sodium transporters HKT1;4 and HKT1; 5 were identified as the respective candidate genes. These transporters retrieve Na\(^+\) from the xylem, thus limiting the rates of Na\(^+\) transport from the root to the shoot. In this work, we show that the Nax loci also affect activity and expression levels of the SOS1-like Na\(^+\)/H\(^+\) exchanger in both root cortical and stelar tissues. Net Na\(^+\) efflux measured in isolated steles from salt-treated plants, using the non-invasive ion flux measuring MIFE technique, decreased in the sequence: Tamaroi (parental line)>Nax1=Nax2>Nax1:Nax2 lines. This efflux was sensitive to amiloride (a known inhibitor of the Na\(^+\)/H\(^+\) exchanger) and was mirrored by net H\(^+\) flux changes. TdSOS1 relative transcript levels were 6-10-fold lower in Nax lines compared with Tamaroi. Thus, it appears that Nax loci confer two highly complementary mechanisms, both of which contribute towards reducing the xylem Na\(^+\) content. One enhances the retrieval of Na\(^+\) back into the root stele via HKT1;4 or HKT1;5, whilst the other reduces the rate of Na\(^+\) loading into the xylem via SOS1. It is suggested that such duality plays an important adaptive role with greater versatility for responding to a changing environment and controlling Na\(^+\) delivery to the shoot. KW - HKT transporter KW - potassium KW - salinity stress KW - sequestration KW - sodium KW - xylem loading Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-190908 VL - 67 IS - 3 ER - TY - JOUR A1 - Chopra, Martin A1 - Biehl, Marlene A1 - Steinfatt, Tim A1 - Brandl, Andreas A1 - Kums, Juliane A1 - Amich, Jorge A1 - Vaeth, Martin A1 - Kuen, Janina A1 - Holtappels, Rafaela A1 - Podlech, Jürgen A1 - Mottok, Anja A1 - Kraus, Sabrina A1 - Jordán-Garotte, Ana-Laura A1 - Bäuerlein, Carina A. A1 - Brede, Christian A1 - Ribechini, Eliana A1 - Fick, Andrea A1 - Seher, Axel A1 - Polz, Johannes A1 - Ottmueller, Katja J. A1 - Baker, Jeannette A1 - Nishikii, Hidekazu A1 - Ritz, Miriam A1 - Mattenheimer, Katharina A1 - Schwinn, Stefanie A1 - Winter, Thorsten A1 - Schäfer, Viktoria A1 - Krappmann, Sven A1 - Einsele, Hermann A1 - Müller, Thomas D. A1 - Reddehase, Matthias J. A1 - Lutz, Manfred B. A1 - Männel, Daniela N. A1 - Berberich-Siebelt, Friederike A1 - Wajant, Harald A1 - Beilhack, Andreas T1 - Exogenous TNFR2 activation protects from acute GvHD via host T reg cell expansion JF - Journal of Experimental Medicine N2 - Donor CD4\(^+\)Foxp3\(^+\) regulatory T cells (T reg cells) suppress graft-versus-host disease (GvHD) after allogeneic hematopoietic stem cell transplantation (HCT allo-HCT]). Current clinical study protocols rely on the ex vivo expansion of donor T reg cells and their infusion in high numbers. In this study, we present a novel strategy for inhibiting GvHD that is based on the in vivo expansion of recipient T reg cells before allo-HCT, exploiting the crucial role of tumor necrosis factor receptor 2 (TNFR2) in T reg cell biology. Expanding radiation-resistant host T reg cells in recipient mice using a mouse TNFR2-selective agonist before allo-HCT significantly prolonged survival and reduced GvHD severity in a TNFR2-and T reg cell-dependent manner. The beneficial effects of transplanted T cells against leukemia cells and infectious pathogens remained unaffected. A corresponding human TNFR2-specific agonist expanded human T reg cells in vitro. These observations indicate the potential of our strategy to protect allo-HCT patients from acute GvHD by expanding T reg cells via selective TNFR2 activation in vivo. KW - Tumor-necrosis-factor KW - Regulatory-cells KW - Bone marrow transplantantation KW - Graft-versus-leukemia KW - Rheumatoid arthritis KW - Autoimmune diseases KW - Factor receptor KW - Alpha therapy KW - Expression KW - Suppression Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-187640 VL - 213 IS - 9 ER - TY - JOUR A1 - Horn, Hannes A1 - Keller, Alexander A1 - Hildebrandt, Ulrich A1 - Kämpfer, Peter A1 - Riederer, Markus A1 - Hentschel, Ute T1 - Draft genome of the \(Arabidopsis\) \(thaliana\) phyllosphere bacterium, \(Williamsia\) sp. ARP1 JF - Standards in Genomic Sciences N2 - The Gram-positive actinomycete \(Williamsia\) sp. ARP1 was originally isolated from the \(Arabidopsis\) \(thaliana\) phyllosphere. Here we describe the general physiological features of this microorganism together with the draft genome sequence and annotation. The 4,745,080 bp long genome contains 4434 protein-coding genes and 70 RNA genes. To our knowledge, this is only the second reported genome from the genus \(Williamsia\) and the first sequenced strain from the phyllosphere. The presented genomic information is interpreted in the context of an adaptation to the phyllosphere habitat. KW - arabidopsis thaliana KW - whole genome sequencing KW - adaption KW - Williamsia sp. ARP1 KW - phyllosphere KW - draft genome KW - next generation sequencing KW - assembly KW - annotation Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-146008 VL - 11 IS - 8 ER - TY - JOUR A1 - Böhm, Jennifer A1 - Scherzer, Sönke A1 - Krol, Elzbieta A1 - Kreuzer, Ines A1 - von Meyer, Katharina A1 - Lorey, Christian A1 - Mueller, Thomas D. A1 - Shabala, Lana A1 - Monte, Isabel A1 - Salano, Roberto A1 - Al-Rasheid, Khaled A. S. A1 - Rennenberg, Heinz A1 - Shabala, Sergey A1 - Neher, Erwin A1 - Hedrich, Rainer T1 - The Venus Flytrap Dionaea muscipula Counts Prey-Induced Action Potentials to Induce Sodium Uptake JF - Current Biology N2 - Carnivorous plants, such as the Venus flytrap (Dionaea muscipula), depend on an animal diet when grown in nutrient-poor soils. When an insect visits the trap and tilts the mechanosensors on the inner surface, action potentials (APs) are fired. After a moving object elicits two APs, the trap snaps shut, encaging the victim. Panicking preys repeatedly touch the trigger hairs over the subsequent hours, leading to a hermetically closed trap, which via the gland-based endocrine system is flooded by a prey-decomposing acidic enzyme cocktail. Here, we asked the question as to how many times trigger hairs have to be stimulated (e.g., now many APs are required) for the flytrap to recognize an encaged object as potential food, thus making it worthwhile activating the glands. By applying a series of trigger-hair stimulations, we found that the touch hormone jasmonic acid (JA) signaling pathway is activated after the second stimulus, while more than three APs are required to trigger an expression of genes encoding prey-degrading hydrolases, and that this expression is proportional to the number of mechanical stimulations. A decomposing animal contains a sodium load, and we have found that these sodium ions enter the capture organ via glands. We identified a flytrap sodium channel DmHKT1 as responsible for this sodium acquisition, with the number of transcripts expressed being dependent on the number of mechano-electric stimulations. Hence, the number of APs a victim triggers while trying to break out of the trap identifies the moving prey as a struggling Na+-rich animal and nutrition for the plant. KW - Venusfliegenfalle KW - Dionaea muscipula Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-128054 VL - 26 IS - 3 ER - TY - JOUR A1 - Joensuu, Johanna A1 - Altimir, Nuria A1 - Hakola, Hannele A1 - Rostás, Michael A1 - Raivonen, Maarit A1 - Vestenius, Mika A1 - Aaltonen, Hermanni A1 - Riederer, Markus A1 - Bäck, Jaana T1 - Role of needle surface waxes in dynamic exchange of mono- and sesquiterpenes JF - Atmospheric Chemistry and Physics N2 - Biogenic volatile organic compounds (BVOCs) produced by plants have a major role in atmospheric chemistry. The different physicochemical properties of BVOCs affect their transport within and out of the plant as well as their reactions along the way. Some of these compounds may accumulate in or on the waxy surface layer of conifer needles and participate in chemical reactions on or near the foliage surface. The aim of this work was to determine whether terpenes, a key category of BVOCs produced by trees, can be found on the epicuticles of Scots pine (Pinus sylvestris L.) and, if so, how they compare with the terpenes found in shoot emissions of the same tree. We measured shoot-level emissions of pine seedlings at a remote outdoor location in central Finland and subsequently analysed the needle surface waxes for the same compounds. Both emissions and wax extracts were clearly dominated by monoterpenes, but the proportion of sesquiterpenes was higher in the wax extracts. There were also differences in the terpene spectra of the emissions and the wax extracts. The results, therefore, support the existence of BVOC associated to the epicuticular waxes. We briefly discuss the different pathways for terpenes to reach the needle surfaces and the implications for air chemistry. KW - Biogenic KW - volatile KW - organic KW - compounds Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-198547 VL - 16 ER - TY - JOUR A1 - Böhm, Jennifer A1 - Scherzer, Sönke A1 - Krol, Elzbieta A1 - Kreuzer, Ines A1 - von Meyer, Katharina A1 - Lorey, Christian A1 - Mueller, Thomas D. A1 - Shabala, Lana A1 - Monte, Isabel A1 - Solano, Roberto A1 - Al-Rasheid, Khaled A. S. A1 - Rennenberg, Heinz A1 - Shabala, Sergey A1 - Neher, Erwin A1 - Hedrich, Rainer T1 - The Venus flytrap Dionaea muscipula counts prey-induced action potentials to induce sodium uptake JF - Current Biology N2 - Carnivorous plants, such as the Venus flytrap (Dionaea muscipula), depend on an animal diet when grown in nutrient-poor soils. When an insect visits the trap and tilts the mechanosensors on the inner surface, action potentials (APs) are fired. After a moving object elicits two APs, the trap snaps shut, encaging the victim. Panicking preys repeatedly touch the trigger hairs over the subsequent hours, leading to a hermetically closed trap, which via the gland-based endocrine system is flooded by a prey-decomposing acidic enzyme cocktail. Here, we asked the question as to how many times trigger hairs have to be stimulated (e.g., now many APs are required) for the flytrap to recognize an encaged object as potential food, thus making it worthwhile activating the glands. By applying a series of trigger-hair stimulations, we found that the touch hormone jasmonic acid (JA) signaling pathway is activated after the second stimulus, while more than three APs are required to trigger an expression of genes encoding prey-degrading hydrolases, and that this expression is proportional to the number of mechanical stimulations. A decomposing animal contains a sodium load, and we have found that these sodium ions enter the capture organ via glands. We identified a flytrap sodium channel DmHKT1 as responsible for this sodium acquisition, with the number of transcripts expressed being dependent on the number of mechano-electric stimulations. Hence, the number of APs a victim triggers while trying to break out of the trap identifies the moving prey as a struggling Na\(^+\)-rich animal and nutrition for the plant. KW - jasmonic acid biosynthesis KW - gene expression KW - signal transduction KW - transporters KW - Arabidopsis Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-190870 VL - 26 IS - 3 ER - TY - JOUR A1 - Nukarinen, Ella A1 - Nägele, Thomas A1 - Pedrotti, Lorenzo A1 - Wurzinger, Bernhard A1 - Mair, Andrea A1 - Landgraf, Ramona A1 - Börnke, Frederik A1 - Hanson, Johannes A1 - Teige, Markus A1 - Baena-Gonzalez, Elena A1 - Dröge-Laser, Wolfgang A1 - Weckwerth, Wolfram T1 - Quantitative phosphoproteomics reveals the role of the AMPK plant ortholog SnRK1 as a metabolic master regulator under energy deprivation JF - Scientific Reports N2 - Since years, research on SnRK1, the major cellular energy sensor in plants, has tried to define its role in energy signalling. However, these attempts were notoriously hampered by the lethality of a complete knockout of SnRK1. Therefore, we generated an inducible amiRNA::SnRK1α2 in a snrk1α1 knock out background (snrk1α1/α2) to abolish SnRK1 activity to understand major systemic functions of SnRK1 signalling under energy deprivation triggered by extended night treatment. We analysed the in vivo phosphoproteome, proteome and metabolome and found that activation of SnRK1 is essential for repression of high energy demanding cell processes such as protein synthesis. The most abundant effect was the constitutively high phosphorylation of ribosomal protein S6 (RPS6) in the snrk1α1/α2 mutant. RPS6 is a major target of TOR signalling and its phosphorylation correlates with translation. Further evidence for an antagonistic SnRK1 and TOR crosstalk comparable to the animal system was demonstrated by the in vivo interaction of SnRK1α1 and RAPTOR1B in the cytosol and by phosphorylation of RAPTOR1B by SnRK1α1 in kinase assays. Moreover, changed levels of phosphorylation states of several chloroplastic proteins in the snrk1α1/α2 mutant indicated an unexpected link to regulation of photosynthesis, the main energy source in plants. KW - phosphoproteomics KW - SnRK1 KW - energy deprivation KW - plants Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-167638 VL - 6 IS - 31697 ER - TY - JOUR A1 - Bhavsar, Shefalee K. A1 - Singh, Yogesh A1 - Sharma, Piyush A1 - Khairnar, Vishal A1 - Hosseinzadeh, Zohreh A1 - Zhang, Shaqiu A1 - Palmada, Monica A1 - Sabolic, Ivan A1 - Koepsell, Hermann A1 - Lang, Karl S. A1 - Lang, Philipp A. A1 - Lang, Florian T1 - Expression of JAK3 Sensitive Na\(^+\) Coupled Glucose Carrier SGLT1 in Activated Cytotoxic T Lymphocytes JF - Cellular Physiology and Biochemistry N2 - Background: Similar to tumor cells, activated T-lymphocytes generate ATP mainly by glycolytic degradation of glucose. Lymphocyte glucose uptake involves non-concentrative glucose carriers of the GLUT family. In contrast to GLUT isoforms, Na+-coupled glucose-carrier SGLT1 accumulates glucose against glucose gradients and is effective at low extracellular glucose concentrations. The present study explored expression and regulation of SGLT1 in activated murine splenic cytotoxic T cells (CTLs) and human Jurkat T cells. Methods: FACS analysis, immunofluorescence, confocal microscopy, chemiluminescence and Western blotting were employed to estimate SGLT1 expression, function and regulation in lymphocytes, as well as dual electrode voltage clamp in SGLT1 ± JAK3 expressing Xenopus oocytes to quantify the effect of janus kinase3 (JAK3) on SGLT1 function. Results: SGLT1 is expressed in murine CTLs and also in human Jurkat T cells. 2-(N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino)-2-deoxyglucose uptake was significantly decreased by SGLT1-blocker phloridzin (0.2 mM) and by pharmacological inhibition of JAK3 with WHI-P131 (156 µM), WHI-P154 (11.2 µM) and JAK3 inhibitor VI (0.5 µM). Electrogenic glucose transport (Iglucose) in Xenopus oocytes expressing human SGLT1 was increased by additional expression of human wild type JAK3, active A568VJAK3 but not inactive K851AJAK3. Coexpression of JAK3 enhanced the maximal transport rate without significantly modifying affinity of the carrier. Iglucose in SGLT1+JAK3 expressing oocytes was significantly decreased by WHI-P154 (11.2 µM). JAK3 increased the SGLT1 protein abundance in the cell membrane. Inhibition of carrier insertion by brefeldin A (5 µM) in SGLT1+JAK3 expressing oocytes resulted in a decline of Iglucose, which was similar in presence and absence of JAK3. Conclusions: SGLT1 is expressed in murine cytotoxic T cells and human Jurkat T cells and significantly contributes to glucose uptake in those cells post activation. JAK3 up-regulates SGLT1 activity by increasing the carrier protein abundance in the cell membrane, an effect enforcing cellular glucose uptake into activated lymphocytes and thus contributing to the immune response. KW - tumor cell KW - Cytotoxic T lymphocytes KW - Glucose uptake KW - Jurkat T cells KW - Energy depletion KW - Janus kinase Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-164900 VL - 39 IS - 3 ER - TY - JOUR A1 - Boschert, V. A1 - Frisch, C. A1 - Back, J. W. A1 - van Pee,, K. A1 - Weidauer, S. E. A1 - Muth, E.-M. A1 - Schmieder, P. A1 - Beerbaum, M. A1 - Knappik, A. A1 - Timmerman, P. A1 - Mueller, T. D. T1 - The sclerostin-neutralizing antibody AbD09097 recognizes an epitope adjacent to sclerostin's binding site for the Wnt co-receptor LRP6 JF - Open Biology N2 - The glycoprotein sclerostin has been identified as a negative regulator of bone growth. It exerts its function by interacting with the Wnt co-receptor LRP5/6, blocks the binding of Wnt factors and thereby inhibits Wnt signalling. Neutralizing anti-sclerostin antibodies are able to restore Wnt activity and enhance bone growth thereby presenting a new osteoanabolic therapy approach for diseases such as osteoporosis. We have generated various Fab antibodies against human and murine sclerostin using a phage display set-up. Biochemical analyses have identified one Fab developed against murine sclerostin, AbD09097 that efficiently neutralizes sclerostin's Wnt inhibitory activity. In vitro interaction analysis using sclerostin variants revealed that this neutralizing Fab binds to sclerostin's flexible second loop, which has been shown to harbour the LRP5/6 binding motif. Affinity maturation was then applied to AbD09097, providing a set of improved neutralizing Fab antibodies which particularly bind human sclerostin with enhanced affinity. Determining the crystal structure of AbD09097 provides first insights into how this antibody might recognize and neutralize sclerostin. Together with the structure–function relationship derived from affinity maturation these new data will foster the rational design of new and highly efficient anti-sclerostin antibodies for the therapy of bone loss diseases such as osteoporosis. KW - phage display KW - Wnt signalling KW - sclerostin KW - neutralizing antibody KW - osteoporosis Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-177925 VL - 6 ER - TY - JOUR A1 - Böhm, J. A1 - Scherzer, S. A1 - Shabala, S. A1 - Krol, E. A1 - Neher, E. A1 - Mueller, T. D. A1 - Hedrich, R. T1 - Venus flytrap HKT1-type channel provides for prey sodium uptake into carnivorous plant without conflicting with electrical excitability JF - Molecular Plant N2 - The animal diet of the carnivorous Venus flytrap, Dionaea muscipula, contains a sodium load that enters the capture organ via an HKT1-type sodium channel, expressed in special epithelia cells on the inner trap lobe surface. DmHKT1 expression and sodium uptake activity is induced upon prey contact. Here, we analyzed the HKT1 properties required for prey sodium osmolyte management of carnivorous Dionaea. Analyses were based on homology modeling, generation of model-derived point mutants, and their functional testing in Xenopus oocytes. We showed that the wild-type HKT1 and its Na\(^+\)- and K\(^+\)-permeable mutants function as ion channels rather than K\(^+\) transporters driven by proton or sodium gradients. These structural and biophysical features of a high-capacity, Na\(^+\)-selective ion channel enable Dionaea glands to manage prey-derived sodium loads without confounding the action potential-based information management of the flytrap. KW - sodium channel KW - HKT1 KW - Dionaea muscipula KW - action potential KW - glands KW - sodium uptake Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-189803 VL - 9 IS - 3 ER - TY - JOUR A1 - Klughammer, Christof A1 - Schreiber, Ulrich T1 - Deconvolution of ferredoxin, plastocyanin, and P700 transmittance changes in intact leaves with a new type of kinetic LED array spectrophotometer JF - Photosynthesis Research N2 - A newly developed compact measuring system for assessment of transmittance changes in the near-infrared spectral region is described; it allows deconvolution of redox changes due to ferredoxin (Fd), P700, and plastocyanin (PC) in intact leaves. In addition, it can also simultaneously measure chlorophyll fluorescence. The major opto-electronic components as well as the principles of data acquisition and signal deconvolution are outlined. Four original pulse-modulated dual-wavelength difference signals are measured (785-840 nm, 810-870 nm, 870-970 nm, and 795-970 nm). Deconvolution is based on specific spectral information presented graphically in the form of 'Differential Model Plots' (DMP) of Fd, P700, and PC that are derived empirically from selective changes of these three components under appropriately chosen physiological conditions. Whereas information on maximal changes of Fd is obtained upon illumination after dark-acclimation, maximal changes of P700 and PC can be readily induced by saturating light pulses in the presence of far-red light. Using the information of DMP and maximal changes, the new measuring system enables on-line deconvolution of Fd, P700, and PC. The performance of the new device is demonstrated by some examples of practical applications, including fast measurements of flash relaxation kinetics and of the Fd, P700, and PC changes paralleling the polyphasic fluorescence rise upon application of a 300-ms pulse of saturating light. KW - Chlorophyll fluorescence KW - Cyclic electron transport KW - FeS proteins KW - Flash relaxation kinetics KW - Photosystem I KW - Polyphasic fluorescence rise KW - Thioredoxin Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-189050 VL - 128 IS - 2 ER - TY - JOUR A1 - Cicova, Zdenka A1 - Dejung, Mario A1 - Skalicky, Tomas A1 - Eisenhuth, Nicole A1 - Hanselmann, Steffen A1 - Morriswood, Brooke A1 - Figueiredo, Luisa M. A1 - Butter, Falk A1 - Janzen, Christian J. T1 - Two flagellar BAR domain proteins in Trypanosoma brucei with stage-specific regulation JF - Scientific Reports N2 - Trypanosomes are masters of adaptation to different host environments during their complex life cycle. Large-scale proteomic approaches provide information on changes at the cellular level, and in a systematic way. However, detailed work on single components is necessary to understand the adaptation mechanisms on a molecular level. Here, we have performed a detailed characterization of a bloodstream form (BSF) stage-specific putative flagellar host adaptation factor Tb927.11.2400, identified previously in a SILAC-based comparative proteome study. Tb927.11.2400 shares 38% amino acid identity with TbFlabarin (Tb927.11.2410), a procyclic form (PCF) stage-specific flagellar BAR domain protein. We named Tb927.11.2400 TbFlabarin-like (TbFlabarinL), and demonstrate that it originates from a gene duplication event, which occurred in the African trypanosomes. TbFlabarinL is not essential for the growth of the parasites under cell culture conditions and it is dispensable for developmental differentiation from BSF to the PCF in vitro. We generated TbFlabarinL-specific antibodies, and showed that it localizes in the flagellum. Co-immunoprecipitation experiments together with a biochemical cell fractionation suggest a dual association of TbFlabarinL with the flagellar membrane and the components of the paraflagellar rod. KW - parasite biology KW - protein translocation KW - Trypanosoma brucei Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-181021 VL - 6 ER - TY - JOUR A1 - Jakobson, Liina A1 - Vaahtera, Lauri A1 - Tõldsepp, Kadri A1 - Nuhkat, Maris A1 - Wang, Cun A1 - Wang, Yuh-Shuh A1 - Hõrak, Hanna A1 - Valk, Ervin A1 - Pechter, Priit A1 - Sindarovska, Yana A1 - Tang, Jing A1 - Xiao, Chuanlei A1 - Xu, Yang A1 - Talas, Ulvi Gerst A1 - García-Sosa, Alfonso T. A1 - Kangasjärvi, Saijaliisa A1 - Maran, Uko A1 - Remm, Maido A1 - Roelfsema, M. Rob G. A1 - Hu, Honghong A1 - Kangasjärvi, Jaakko A1 - Loog, Mart A1 - Schroeder, Julian I. A1 - Kollist, Hannes A1 - Brosché, Mikael T1 - Natural Variation in Arabidopsis Cvi-0 Accession Reveals an Important Role of MPK12 in Guard Cell CO\(_{2}\) Signaling JF - PLoS Biology N2 - Plant gas exchange is regulated by guard cells that form stomatal pores. Stomatal adjustments are crucial for plant survival; they regulate uptake of CO\(_{2}\) for photosynthesis, loss of water, and entrance of air pollutants such as ozone. We mapped ozone hypersensitivity, more open stomata, and stomatal CO\(_{2}\)-insensitivity phenotypes of the Arabidopsis thaliana accession Cvi-0 to a single amino acid substitution in MITOGEN-ACTIVATED PROTEIN (MAP) KINASE 12 (MPK12). In parallel, we showed that stomatal CO\(_{2}\)-insensitivity phenotypes of a mutant cis (CO\(_{2}\)-insensitive) were caused by a deletion of MPK12. Lack of MPK12 impaired bicarbonate-induced activation of S-type anion channels. We demonstrated that MPK12 interacted with the protein kinase HIGH LEAF TEMPERATURE 1 (HT1)—a central node in guard cell CO\(_{2}\) signaling—and that MPK12 functions as an inhibitor of HT1. These data provide a new function for plant MPKs as protein kinase inhibitors and suggest a mechanism through which guard cell CO\(_{2}\) signaling controls plant water management. KW - MPK12 KW - CO\(_{2}\) signaling KW - Arabidopsis thaliana KW - Cvi-0 Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-166657 VL - 14 IS - 12 ER - TY - JOUR A1 - Shepard, Blythe D. A1 - Cheval, Lydie A1 - Peterlin, Zita A1 - Firestein, Stuart A1 - Koepsell, Hermann A1 - Doucet, Alain A1 - Pluznick, Jennifer L. T1 - A Renal Olfactory Receptor Aids in Kidney Glucose Handling JF - Scientific Reports N2 - Olfactory receptors (ORs) are G protein-coupled receptors which serve important sensory functions beyond their role as odorant detectors in the olfactory epithelium. Here we describe a novel role for one of these ORs, Olfr1393, as a regulator of renal glucose handling. Olfr1393 is specifically expressed in the kidney proximal tubule, which is the site of renal glucose reabsorption. Olfr1393 knockout mice exhibit urinary glucose wasting and improved glucose tolerance, despite euglycemia and normal insulin levels. Consistent with this phenotype, Olfr1393 knockout mice have a significant decrease in luminal expression of Sglt1, a key renal glucose transporter, uncovering a novel regulatory pathway involving Olfr1393 and Sglt1. In addition, by utilizing a large scale screen of over 1400 chemicals we reveal the ligand profile of Olfr1393 for the first time, offering new insight into potential pathways of physiological regulation for this novel signaling pathway. KW - olfactory receptor KW - Olfr1393 KW - kidney KW - glucose handling Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-167605 VL - 6 IS - 35215 ER - TY - JOUR A1 - Gallo, Linda A. A1 - Ward, Micheal S. A1 - Fotheringham, Amelia K. A1 - Zhuang, Aowen A1 - Borg, Danielle J. A1 - Flemming, Nicole B. A1 - Harvie, Ben M. A1 - Kinneally, Toni L. A1 - Yeh, Shang-Ming A1 - McCarthy, Domenica A. A1 - Koepsell, Hermann A1 - Vallon, Volker A1 - Pollock, Carol A1 - Panchapakesan, Usha A1 - Forbes, Josephine M. T1 - Once daily administration of the SGLT2 inhibitor, empagliflozin, attenuates markers of renal fibrosis without improving albuminuria in diabetic db/db mice JF - Scientific Reports N2 - Blood glucose control is the primary strategy to prevent complications in diabetes. At the onset of kidney disease, therapies that inhibit components of the renin angiotensin system (RAS) are also indicated, but these approaches are not wholly effective. Here, we show that once daily administration of the novel glucose lowering agent, empagliflozin, an SGLT2 inhibitor which targets the kidney to block glucose reabsorption, has the potential to improve kidney disease in type 2 diabetes. In male db/db mice, a 10-week treatment with empagliflozin attenuated the diabetes-induced upregulation of profibrotic gene markers, fibronectin and transforming-growth-factor-beta. Other molecular (collagen IV and connective tissue growth factor) and histological (tubulointerstitial total collagen and glomerular collagen IV accumulation) benefits were seen upon dual therapy with metformin. Albuminuria, urinary markers of tubule damage (kidney injury molecule-1, KIM-1 and neutrophil gelatinase-associated lipocalin, NGAL), kidney growth, and glomerulosclerosis, however, were not improved with empagliflozin or metformin, and plasma and intra-renal renin activity was enhanced with empagliflozin. In this model, blood glucose lowering with empagliflozin attenuated some molecular and histological markers of fibrosis but, as per treatment with metformin, did not provide complete renoprotection. Further research to refine the treatment regimen in type 2 diabetes and nephropathy is warranted. KW - SGLT2 inhibitor KW - empagliflozin KW - glucose lowering agent KW - kidney disease KW - type 2 diabetes Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-167678 VL - 6 IS - 26428 ER - TY - JOUR A1 - Schuster, Ann-Christin A1 - Burghardt, Markus A1 - Alfarhan, Ahmed A1 - Bueno, Amauri A1 - Hedrich, Rainer A1 - Leide, Jana A1 - Thomas, Jacob A1 - Riederer, Markus T1 - Effectiveness of cuticular transpiration barriers in a desert plant at controlling water loss at high temperatures JF - AoB Plants N2 - Maintaining the integrity of the cuticular transpiration barrier even at elevated temperatures is of vital importance especially for hot-desert plants. Currently, the temperature dependence of the leaf cuticular water permeability and its relationship with the chemistry of the cuticles are not known for a single desert plant. This study investigates whether (i) the cuticular permeability of a desert plant is lower than that of species from non-desert habitats, (ii) the temperature-dependent increase of permeability is less pronounced than in those species and (iii) whether the susceptibility of the cuticular permeability barrier to high temperatures is related to the amounts or properties of the cutin or the cuticular waxes. We test these questions with Rhazya stricta using the minimum leaf water vapour conductance (gmin) as a proxy for cuticular water permeability. gmin of R. stricta (5.41 × 10\(^{-5}\) m s\(^{-1}\) at 25 °C) is in the upper range of all existing data for woody species from various non-desert habitats. At the same time, in R. stricta, the effect of temperature (15-50 °C) on gmin (2.4-fold) is lower than in all other species (up to 12-fold). Rhazya stricta is also special since the temperature dependence of gmin does not become steeper above a certain transition temperature. For identifying the chemical and physical foundation of this phenomenon, the amounts and the compositions of cuticular waxes and cutin were determined. The leaf cuticular wax (251.4 μg cm\(^{-2}\)) is mainly composed of pentacyclic triterpenoids (85.2% of total wax) while long-chain aliphatics contribute only 3.4%. In comparison with many other species, the triterpenoid-to-cutin ratio of R. stricta (0.63) is high. We propose that the triterpenoids deposited within the cutin matrix restrict the thermal expansion of the polymer and, thus, prevent thermal damage to the highly ordered aliphatic wax barrier even at high temperatures. KW - conductance KW - triterpenoids KW - aliphatic compounds KW - cuticular transpiration KW - cuticular wax KW - cutin KW - desert KW - minimum KW - plant cuticle KW - temperature KW - transition temperature Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-160963 VL - 8 ER - TY - JOUR A1 - Jahn, Martin T. A1 - Markert, Sebastian M. A1 - Ryu, Taewoo A1 - Ravasi, Timothy A1 - Stigloher, Christian A1 - Hentschel, Ute A1 - Moitinho-Silva, Lucas T1 - Shedding light on cell compartmentation in the candidate phylum Poribacteria by high resolution visualisation and transcriptional profiling JF - Scientific Reports N2 - Assigning functions to uncultivated environmental microorganisms continues to be a challenging endeavour. Here, we present a new microscopy protocol for fluorescence in situ hybridisation-correlative light and electron microscopy (FISH-CLEM) that enabled, to our knowledge for the first time, the identification of single cells within their complex microenvironment at electron microscopy resolution. Members of the candidate phylum Poribacteria, common and uncultivated symbionts of marine sponges, were used towards this goal. Cellular 3D reconstructions revealed bipolar, spherical granules of low electron density, which likely represent carbon reserves. Poribacterial activity profiles were retrieved from prokaryotic enriched sponge metatranscriptomes using simulation-based optimised mapping. We observed high transcriptional activity for proteins related to bacterial microcompartments (BMC) and we resolved their subcellular localisation by combining FISH-CLEM with immunohistochemistry (IHC) on ultra-thin sponge tissue sections. In terms of functional relevance, we propose that the BMC-A region may be involved in 1,2-propanediol degradation. The FISH-IHC-CLEM approach was proven an effective toolkit to combine -omics approaches with functional studies and it should be widely applicable in environmental microbiology. KW - high resolution visualisation KW - transcriptional profiling KW - FISH-CLEM KW - cell compartmentation Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-167513 VL - 6 IS - 35860 ER - TY - JOUR A1 - Burgsdorf, Ilia A1 - Slaby, Beate M. A1 - Handley, Kim M. A1 - Haber, Markus A1 - Blom, Jochen A1 - Marshall, Christopher W. A1 - Gilbert, Jack A. A1 - Hentschel, Ute A1 - Steindler, Laura T1 - Lifestyle Evolution in Cyanobacterial Symbionts of Sponges JF - mBio N2 - The "Candidatus Synechococcus spongiarum" group includes different clades of cyanobacteria with high 16S rRNA sequence identity (~99%) and is the most abundant and widespread cyanobacterial symbiont of marine sponges. The first draft genome of a "Ca. Synechococcus spongiarum" group member was recently published, providing evidence of genome reduction by loss of genes involved in several nonessential functions. However, "Ca. Synechococcus spongiarum" includes a variety of clades that may differ widely in genomic repertoire and consequently in physiology and symbiotic function. Here, we present three additional draft genomes of "Ca. Synechococcus spongiarum," each from a different clade. By comparing all four symbiont genomes to those of free-living cyanobacteria, we revealed general adaptations to life inside sponges and specific adaptations of each phylotype. Symbiont genomes shared about half of their total number of coding genes. Common traits of "Ca. Synechococcus spongiarum" members were a high abundance of DNA modification and recombination genes and a reduction in genes involved in inorganic ion transport and metabolism, cell wall biogenesis, and signal transduction mechanisms. Moreover, these symbionts were characterized by a reduced number of antioxidant enzymes and low-weight peptides of photosystem II compared to their free-living relatives. Variability within the "Ca. Synechococcus spongiarum" group was mostly related to immune system features, potential for siderophore-mediated iron transport, and dependency on methionine from external sources. The common absence of genes involved in synthesis of residues, typical of the O antigen of free-living Synechococcus species, suggests a novel mechanism utilized by these symbionts to avoid sponge predation and phage attack. IMPORTANCE While the Synechococcus/Prochlorococcus-type cyanobacteria are widely distributed in the world's oceans, a subgroup has established its niche within marine sponge tissues. Recently, the first genome of sponge-associated cyanobacteria, " Candidatus Synechococcus spongiarum," was described. The sequencing of three representatives of different clades within this cyanobacterial group has enabled us to investigate intraspecies diversity, as well as to give a more comprehensive understanding of the common symbiotic features that adapt "Ca. Synechococcus spongiarum" to its life within the sponge host. KW - marine Synechococcus strains KW - ribosomal RNA genes KW - single cell KW - vertical transmission KW - microbial communities KW - sequence analysis KW - spacer sequences KW - genomic analysis KW - web server KW - reveals Y1 - 2015 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-143117 VL - 6 IS - 3 ER - TY - JOUR A1 - Jurowich, Christian Ferdinand A1 - Otto, Christoph A1 - Rikkala, Prashanth Reddy A1 - Wagner, Nicole A1 - Vrhovac, Ivana A1 - Sabolić, Ivan A1 - Germer, Christoph-Thomas A1 - Koepsell, Hermann T1 - Ileal interposition in rats with experimental type 2 like diabetes improves glycemic control independently of glucose absorption JF - Journal of Diabetes Research N2 - Bariatric operations in obese patients with type 2 diabetes often improve diabetes before weight loss is observed. In patients mainly Roux-en-Y-gastric bypass with partial stomach resection is performed. Duodenojejunal bypass (DJB) and ileal interposition (IIP) are employed in animal experiments. Due to increased glucose exposition of L-cells located in distal ileum, all bariatric surgery procedures lead to higher secretion of antidiabetic glucagon like peptide-1 (GLP-1) after glucose gavage. After DJB also downregulation of Na\(^{+}\)-D-glucose cotransporter SGLT1 was observed. This suggested a direct contribution of decreased glucose absorption to the antidiabetic effect of bariatric surgery. To investigate whether glucose absorption is also decreased after IIP, we induced diabetes with decreased glucose tolerance and insulin sensitivity in male rats and investigated effects of IIP on diabetes and SGLT1. After IIP, we observed weight-independent improvement of glucose tolerance, increased insulin sensitivity, and increased plasma GLP-1 after glucose gavage. The interposed ileum was increased in diameter and showed increased length of villi, hyperplasia of the epithelial layer, and increased number of L-cells. The amount of SGLT1-mediated glucose uptake in interposed ileum was increased 2-fold reaching the same level as in jejunum. Thus, improvement of glycemic control by bariatric surgery does not require decreased glucose absorption. KW - glucagon like peptide-1 KW - food intake KW - body weight KW - cotransporter SGLT1 KW - bariatric surgery KW - biliopancreatic diversion KW - intestinal glucose KW - gut hormones KW - duodenal jejunal bypass KW - Y-gastric bypass Y1 - 2015 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-149166 VL - 2015 IS - 490365 ER - TY - JOUR A1 - Planes, Maria D. A1 - Niñoles, Regina A1 - Rubio, Lourdes A1 - Bissoli, Gaetano A1 - Bueso, Eduardo A1 - García-Sánchez, María J. A1 - Alejandro, Santiago A1 - Gonzalez-Guzmán, Miguel A1 - Hedrich, Rainer A1 - Rodriguez, Pedro L. A1 - Fernández, José A. A1 - Serrano, Ramón T1 - A mechanism of growth inhibition by abscisic acid in germinating seeds of Arabidopsis thaliana based on inhibition of plasma membrane \(H^+\)-ATPase and decreased cytosolic pH, \(K^+\), and anions JF - Journal of Experimental Botany N2 - The stress hormone abscisic acid (ABA) induces expression of defence genes in many organs, modulates ion homeostasis and metabolism in guard cells, and inhibits germination and seedling growth. Concerning the latter effect, several mutants of Arabidopsis thaliana with improved capability for \(H^+\) efflux (wat1-1D, overexpression of AKT1 and ost2-1D) are less sensitive to inhibition by ABA than the wild type. This suggested that ABA could inhibit \(H^+\) efflux (\(H^+\)-ATPase) and induce cytosolic acidification as a mechanism of growth inhibition. Measurements to test this hypothesis could not be done in germinating seeds and we used roots as the most convenient system. ABA inhibited the root plasma-membrane H+-ATPase measured in vitro (ATP hydrolysis by isolated vesicles) and in vivo (\(H^+\) efflux from seedling roots). This inhibition involved the core ABA signalling elements: PYR/PYL/RCAR ABA receptors, ABA-inhibited protein phosphatases (HAB1), and ABA-activated protein kinases (SnRK2.2 and SnRK2.3). Electrophysiological measurements in root epidermal cells indicated that ABA, acting through the PYR/PYL/RCAR receptors, induced membrane hyperpolarization (due to \(K^+\) efflux through the GORK channel) and cytosolic acidification. This acidification was not observed in the wat1-1D mutant. The mechanism of inhibition of the \(H^+\)-ATPase by ABA and its effects on cytosolic pH and membrane potential in roots were different from those in guard cells. ABA did not affect the in vivo phosphorylation level of the known activating site (penultimate threonine) of (\(H^+\)-ATPase in roots, and SnRK2.2 phosphorylated in vitro the C-terminal regulatory domain of (\(H^+\)-ATPase while the guard-cell kinase SnRK2.6/OST1 did not. KW - ABA receptors KW - cytosolic pH KW - ion channels KW - microelectrodes KW - protein kinase KW - proton efflux Y1 - 2015 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-121221 VL - 66 IS - 3 ER - TY - JOUR A1 - Cheng, Cheng A1 - MacIntyre, Lynsey A1 - Ramadan Abdelmohsen, Usama A1 - Horn, Hannes A1 - Polymenakou, Paraskevi N. A1 - Edrada-Ebel, RuAngelie A1 - Hentschel, Ute T1 - Biodiversity, Anti-Trypanosomal Activity Screening, and Metabolomic Profiling of Actinomycetes Isolated from Mediterranean Sponges JF - PLoS One N2 - Marine sponge–associated actinomycetes are considered as promising sources for the discovery of novel biologically active compounds. In the present study, a total of 64 actinomycetes were isolated from 12 different marine sponge species that had been collected offshore the islands of Milos and Crete, Greece, eastern Mediterranean. The isolates were affiliated to 23 genera representing 8 different suborders based on nearly full length 16S rRNA gene sequencing. Four putatively novel species belonging to genera Geodermatophilus, Microlunatus, Rhodococcus and Actinomycetospora were identified based on a 16S rRNA gene sequence similarity of < 98.5% to currently described strains. Eight actinomycete isolates showed bioactivities against Trypanosma brucei brucei TC221 with half maximal inhibitory concentration (IC50) values <20 μg/mL. Thirty four isolates from the Milos collection and 12 isolates from the Crete collection were subjected to metabolomic analysis using high resolution LC-MS and NMR for dereplication purposes. Two isolates belonging to the genera Streptomyces (SBT348) and Micromonospora (SBT687) were prioritized based on their distinct chemistry profiles as well as their anti-trypanosomal activities. These findings demonstrated the feasibility and efficacy of utilizing metabolomics tools to prioritize chemically unique strains from microorganism collections and further highlight sponges as rich source for novel and bioactive actinomycetes. KW - streptomyces KW - drug metabolism KW - metabolites KW - ribosomal RNA KW - metabolomics KW - actinobacteria KW - sponges KW - secondary metabolites Y1 - 2015 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-125138 VL - 10 IS - 9 ER - TY - JOUR A1 - Horn, Hannes A1 - Hentschel, Ute A1 - Ramadan Abdelmohsen, Usama T1 - Mining Genomes of Three Marine Sponge-Associated Actinobacterial Isolates for Secondary Metabolism JF - Genome Announcements N2 - Here, we report the draft genome sequences of three actinobacterial isolates, Micromonospora sp. RV43, Rubrobacter sp. RV113, and Nocardiopsis sp. RV163 that had previously been isolated from Mediterranean sponges. The draft genomes were analyzed for the presence of gene clusters indicative of secondary metabolism using antiSMASH 3.0 and NapDos pipelines. Our findings demonstrated the chemical richness of sponge-associated actinomycetes and the efficacy of genome mining in exploring the genomic potential of sponge-derived actinomycetes. Y1 - 2015 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-124887 VL - 3 IS - 5 ER - TY - JOUR A1 - Adelfinger, Marion A1 - Bessler, Simon A1 - Cecil, Alexander A1 - Langbein-Laugwitz, Johanna A1 - Frentzen, Alexa A1 - Gentschev, Ivaylo A1 - Szalay, Aladar A. T1 - Preclinical Testing Oncolytic Vaccinia Virus Strain GLV-5b451 Expressing an Anti-VEGF Single-Chain Antibody for Canine Cancer Therapy JF - Viruses N2 - Virotherapy on the basis of oncolytic vaccinia virus (VACV) strains is a novel approach for canine cancer therapy. Here we describe, for the first time, the characterization and the use of VACV strain GLV-5b451 expressing the anti-vascular endothelial growth factor (VEGF) single-chain antibody (scAb) GLAF-2 as therapeutic agent against different canine cancers. Cell culture data demonstrated that GLV-5b451 efficiently infected and destroyed all four tested canine cancer cell lines including: mammary carcinoma (MTH52c), mammary adenoma (ZMTH3), prostate carcinoma (CT1258), and soft tissue sarcoma (STSA-1). The GLV-5b451 virus-mediated production of GLAF-2 antibody was observed in all four cancer cell lines. In addition, this antibody specifically recognized canine VEGF. Finally, in canine soft tissue sarcoma (CSTS) xenografted mice, a single systemic administration of GLV-5b451 was found to be safe and led to anti-tumor effects resulting in the significant reduction and substantial long-term inhibition of tumor growth. A CD31-based immuno-staining showed significantly decreased neo-angiogenesis in GLV-5b451-treated tumors compared to the controls. In summary, these findings indicate that GLV-5b451 has potential for use as a therapeutic agent in the treatment of CSTS. KW - canine cancer therapy KW - canine soft tissue sarcoma (CSTS) KW - oncolytic virus KW - cancer KW - canine cancer cell lines KW - antibody production KW - angiogenesis Y1 - 2015 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-125705 VL - 7 ER - TY - JOUR A1 - Klammert, Uwe A1 - Müller, Thomas D. A1 - Hellmann, Tina V. A1 - Wuerzler, Kristian K. A1 - Kotzsch, Alexander A1 - Schliermann, Anna A1 - Schmitz, Werner A1 - Kuebler, Alexander C. A1 - Sebald, Walter A1 - Nickel, Joachim T1 - GDF-5 can act as a context-dependent BMP-2 antagonist JF - BMC Biology N2 - Background Bone morphogenetic protein (BMP)-2 and growth and differentiation factor (GDF)-5 are two related transforming growth factor (TGF)-β family members with important functions in embryonic development and tissue homeostasis. BMP-2 is best known for its osteoinductive properties whereas GDF-5—as evident from its alternative name, cartilage derived morphogenetic protein 1—plays an important role in the formation of cartilage. In spite of these differences both factors signal by binding to the same subset of BMP receptors, raising the question how these different functionalities are generated. The largest difference in receptor binding is observed in the interaction with the type I receptor BMPR-IA. GDF-5, in contrast to BMP-2, shows preferential binding to the isoform BMPR-IB, which is abrogated by a single amino acid (A57R) substitution. The resulting variant, GDF-5 R57A, represents a “BMP-2 mimic” with respect to BMP receptor binding. In this study we thus wanted to analyze whether the two growth factors can induce distinct signals via an identically composed receptor. Results Unexpectedly and dependent on the cellular context, GDF-5 R57A showed clear differences in its activity compared to BMP-2. In ATDC-5 cells, both ligands induced alkaline phosphatase (ALP) expression with similar potency. But in C2C12 cells, the BMP-2 mimic GDF-5 R57A (and also wild-type GDF-5) clearly antagonized BMP-2-mediated ALP expression, despite signaling in both cell lines occurring solely via BMPR-IA. The BMP-2- antagonizing properties of GDF-5 and GDF-5 R57A could also be observed in vivo when implanting BMP-2 and either one of the two GDF-5 ligands simultaneously at heterotopic sites. Conclusions Although comparison of the crystal structures of the GDF-5 R57A:BMPR-IAEC- and BMP-2:BMPR-IAEC complex revealed small ligand-specific differences, these cannot account for the different signaling characteristics because the complexes seem identical in both differently reacting cell lines. We thus predict an additional component, most likely a not yet identified GDF-5-specific co-receptor, which alters the output of the signaling complexes. Hence the presence or absence of this component then switches GDF-5′s signaling capabilities to act either similar to BMP-2 or as a BMP-2 antagonist. These findings might shed new light on the role of GDF-5, e.g., in cartilage maintenance and/or limb development in that it might act as an inhibitor of signaling events initiated by other BMPs. KW - growth and differentiation factor 5 KW - ligand-receptor complex KW - crystal structure KW - antagonist Y1 - 2015 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-125550 VL - 13 IS - 77 ER - TY - JOUR A1 - Zhang, Yi A1 - Lee, Chil-Woo A1 - Wehner, Nora A1 - Imdahl, Fabian A1 - Svetlana, Veselova A1 - Weiste, Christoph A1 - Dröge-Laser, Wolfgang A1 - Deeken, Rosalia T1 - Regulation of Oncogene Expression in T-DNA-Transformed Host Plant Cells JF - PLoS Pathogens N2 - Virulent Agrobacterium tumefaciens strains integrate their T-DNA into the plant genome where the encoded agrobacterial oncogenes are expressed and cause crown gall disease. Essential for crown gall development are IaaH (indole-3-acetamide hydrolase), IaaM (tryptophan monooxygenase) and Ipt (isopentenyl transferase), which encode enzymes for the biosynthesis of auxin (IaaH, IaaM) and cytokinin (Ipt). Although these oncogenes are well studied as the tumor-inducing principle, nothing is known about the regulation of oncogene expression in plant cells. Our studies show that the intergenic regions (IGRs) between the coding sequences (CDS) of the three oncogenes function as promoters in plant cells. These promoters possess a eukaryotic sequence organization and cis-regulatory elements for the binding of plant transcription factors. WRKY18, WRKY40, WRKY60 and ARF5 were identified as activators of the Ipt promoter whereas IaaH and IaaM is constitutively expressed and no transcription factor further activates their promoters. Consistent with these results, the wrky triple mutant plants in particular, develops smaller crown galls than wild-type and exhibits a reduced Ipt transcription, despite the presence of an intact ARF5 gene. WRKY40 and WRKY60 gene expression is induced by A. tumefaciens within a few hours whereas the ARF5 gene is transcribed later during crown gall development. The WRKY proteins interact with ARF5 in the plant nucleus, but only WRKY40 together with ARF5 synergistically boosts the activation of the Ipt promoter in an auxin-dependent manner. From our data, we propose that A. tumefaciens initially induces WRKY40 gene expression as a pathogen defense response of the host cell. The WRKY protein is recruited to induce Ipt expression, which initiates cytokinin-dependent host cell division. With increasing auxin levels triggered by ubiquitous expression of IaaH and IaaM, ARF5 is activated and interacts with WRKY40 to potentiate Ipt expression and balance cytokinin and auxin levels for further cell proliferation. KW - luminescence KW - oncogenes KW - agrobacterium tumefaciens KW - transcription factors KW - auxins KW - gene expression KW - cytokinins KW - plant cells Y1 - 2015 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-125256 VL - 11 IS - 1 ER -