@article{MuenchHsinFerberetal.2016,
  author    = {M{\"u}nch, Miriam and Hsin, Chih-Hsuan and Ferber, Elena and Berger, Susanne and M{\"u}ller, Martin J.},
  title     = {Reactive electrophilic oxylipins trigger a heat stress-like response through HSFA1 transcription factors},
  series = {Journal of Experimental Botany},
  volume    = {67},
  journal   = {Journal of Experimental Botany},
  number    = {21},
  doi       = {10.1093/jxb/erw376},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-186766},
  pages     = {6139-6148},
  year      = {2016},
  abstract  = {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.},
  language  = {en}
}
@article{JoensuuAltimirHakolaetal.2016,
  author    = {Joensuu, Johanna and Altimir, Nuria and Hakola, Hannele and Rost{\´a}s, Michael and Raivonen, Maarit and Vestenius, Mika and Aaltonen, Hermanni and Riederer, Markus and B{\"a}ck, Jaana},
  title     = {Role of needle surface waxes in dynamic exchange of mono- and sesquiterpenes},
  series = {Atmospheric Chemistry and Physics},
  volume    = {16},
  journal   = {Atmospheric Chemistry and Physics},
  number    = {12},
  doi       = {10.5194/acp-2015-1024},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-171324},
  pages     = {7813-7823},
  year      = {2016},
  abstract  = {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.},
  language  = {en}
}
@article{VendelovadeLimaLorenzattoetal.2016,
  author    = {Vendelova, Emilia and de Lima, Jeferson Camargo and Lorenzatto, Karina Rodrigues and Monteiro, Karina Mariante and Mueller, Thomas and Veepaschit, Jyotishman and Grimm, Clemens and Brehm, Klaus and Hrčkov{\´a}, Gabriela and Lutz, Manfred B. and Ferreira, Henrique B. and Nono, Justin Komguep},
  title     = {Proteomic Analysis of Excretory-Secretory Products of Mesocestoides corti Metacestodes Reveals Potential Suppressors of Dendritic Cell Functions},
  series = {PLoS Neglected Tropical Diseases},
  volume    = {10},
  journal   = {PLoS Neglected Tropical Diseases},
  number    = {10},
  doi       = {10.1371/journal.pntd.0005061},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-166742},
  pages     = {e0005061},
  year      = {2016},
  abstract  = {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.},
  language  = {en}
}
@article{PalamidesJodeleitFoehlingeretal.2016,
  author    = {Palamides, Pia and Jodeleit, Henrika and F{\"o}hlinger, Michael and Beigel, Florian and Herbach, Nadja and Mueller, Thomas and Wolf, Eckhard and Siebeck, Matthias and Gropp, Roswitha},
  title     = {A mouse model for ulcerative colitis based on NOD-scid IL2R gamma(null) mice reconstituted with peripheral blood mononuclear cells from affected individuals},
  series = {Disease Models \& Mechanisms},
  volume    = {9},
  journal   = {Disease Models \& Mechanisms},
  doi       = {10.1242/dmm.025452},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-164946},
  pages     = {985-997},
  year      = {2016},
  abstract  = {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.},
  language  = {en}
}
@article{WalperWeisteMuelleretal.2016,
  author    = {Walper, Elisabeth and Weiste, Christoph and Mueller, Martin J. and Hamberg, Mats and Dr{\"o}ge-Laser, Wolfgang},
  title     = {Screen Identifying Arabidopsis Transcription Factors Involved in the Response to 9-Lipoxygenase-Derived Oxylipins},
  series = {PLoS One},
  volume    = {11},
  journal   = {PLoS One},
  number    = {4},
  doi       = {10.1371/journal.pone.0153216},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-146857},
  pages     = {e0153216},
  year      = {2016},
  abstract  = {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.},
  language  = {en}
}
@phdthesis{Oenel2016,
  author    = {{\"O}nel, Ayla},
  title     = {Synthese und Relevanz von Oxylipinen in Bl{\"a}ttern, Wurzeln und Samen von \(Arabidopsis\) \(thaliana\)},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-141647},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2016},
  abstract  = {Die Lipidoxidation kann sowohl enzymatisch als auch nicht enzymatisch erfolgen. Der erste Schritt der enzymatischen Oxidation wird durch Lipoxygenasen katalysiert, von welchen es in Arabidopsis thaliana sechs verschiedene Isoformen gibt. Dabei werden die Lipoxygenasen nach dem Kohlenstoffatom klassifiziert, welches sie oxidieren. Somit geh{\"o}ren die LOX1 und LOX5 zu den 9-Lipoxygenasen, w{\"a}hrend LOX2, LOX3, LOX4 und LOX6 zu den 13 Lipoxygenasen z{\"a}hlen. W{\"a}hrend der Samenalterung findet vermehrt eine Lipidperoxidation statt, welche mit einem Verfall des Samens sowie einer verringerten Keimrate korreliert. Im Rahmen dieser Arbeit wurde zun{\"a}chst erfolgreich ein System zur k{\"u}nstlichen Samenalterung von Arabidopsis thaliana etabliert. Bei der k{\"u}nstlichen Alterung stiegen {\"a}hnlich wie bei der nat{\"u}rlichen Samenalterung oxidierte Lipide an und die Keimrate fiel ab. Nach Alterung konnte ein Anstieg von sechs verschiedenen oxidierten Triacylglycerolen detektiert werden. Es konnte in dieser Arbeit mit Hilfe von Mutanten mit Defekten in mehreren der Lipoxygenase Gene gezeigt werden, dass die Oxidation dieser veresterten Fetts{\"a}uren zum gr{\"o}ßten Teil nicht enzymatisch erfolgt. Bei der Alterung stiegen zudem enzymatisch gebildete 9 Lipoxygenase Produkte wie freie Hydroxy- und Ketofetts{\"a}uren an. Bei einer Analyse der freien oxidierten Fetts{\"a}uren konnte ebenfalls mit Lipoxygenase Mutanten ermittelt werden, dass diese haupts{\"a}chlich via LOX1 oxidiert werden. Die Untersuchung der Keimraten der Lipoxygenase Mutanten nach Alterung zeigte in mehreren Versuchen eine leicht erh{\"o}hte Keimrate der lox1 im Vergleich zum Wildtyp. Eine exogene Behandlung von Wildtyp Samen mit verschiedenen 9-Lipoxygenase Produkten, welche bei der Alterung ansteigen, f{\"u}hrte allerdings nicht zu einer Keimungshemmung. Somit scheinen Produkte wie Hydroxy- und Ketofetts{\"a}uren der 9-Lipoxygenase LOX1 nicht die Hauptursache f{\"u}r die Keimungshemmung nach Alterung zu sein. Dar{\"u}ber hinaus konnte in dieser Arbeit gezeigt werden, dass eine Behandlung der Bl{\"u}ten des Wildtyps mit Methyljasmonat zu einer signifikant h{\"o}heren Keimrate der Samen im Vergleich zu Samen von unbehandelten Pflanzen nach Alterung f{\"u}hrt. Ein „Lipidprofiling" der Samen von mit Methyljasmonat behandelten Pflanzen wies signifikant geringere Gehalte sowohl an freien als auch veresterten oxidierten Fetts{\"a}uren auf, was mit einer erh{\"o}hten Lebensf{\"a}higkeit korrelierte. Diese Erkenntnisse k{\"o}nnten von großer Relevanz f{\"u}r die Landwirtschaft sein, falls eine {\"U}bertragung auf Nutzpflanzen m{\"o}glich ist. Ein weiterer Schwerpunkt dieser Arbeit war eine eingehende Untersuchung der Rolle und Funktion der LOX6. Mit Hilfe von GUS F{\"a}rbungen konnte eine Lokalisation der LOX6 in Bl{\"a}ttern und Wurzeln nachgewiesen werden. Zudem wurde ein 35SLOX6GFP Konstrukt erstellt und in Arabidopsis thaliana Pflanzen stabil transformiert. Mit den selektionierten Linien k{\"o}nnte in Zukunft auch die intrazellul{\"a}re Lokalisation der LOX6 untersucht werden. Außerdem wurden Konstrukte mit dem Reportergen GFP und AOS sowie LOX2 hinter dem 35S Promotor kloniert, welche ebenfalls f{\"u}r weitere Lokalisations- und Kolokalisationsstudien genutzt werden k{\"o}nnen. Zudem wurde mit der Klonierung eines Konstruktes begonnen, um in Zukunft einen spezifischen LOX6 Antik{\"o}rper herstellen und auch die endogene LOX6 Lokalisation in dem Wildtyp analysieren zu k{\"o}nnen. Um die Produkte der LOX6 zu untersuchen, wurden 35SLOX6 Linien sowie die lox6 Mutante verwendet. Obwohl Hydroxyfetts{\"a}uren und Jasmonate Folgeprodukte der LOX6 sind, wiesen die 35SLOX6 Linien weder basal, noch nach Stress erh{\"o}hte Gehalte dieser im Vergleich zum Wildtyp auf. Somit geben die 35SLOX6 Linien einen Hinweis darauf, dass LOX6 im Wildtyp nicht limitierend f{\"u}r die Produktion von Hydroxyfetts{\"a}uren und Jasmonaten sein k{\"o}nnte. Um zu untersuchen, ob das Substrat der LOX6 der limitierende Faktor sein k{\"o}nnte, wurde eine Behandlung mit α Linolens{\"a}ure durchgef{\"u}hrt. Dabei entstanden allerdings nicht mehr Folgeprodukte der LOX6, sondern es fand sowohl in den 35SLOX6 Linien als auch in dem Wildtyp eine massive nicht enzymatische radikalische Oxidation der Fetts{\"a}uren statt. Um festzustellen, ob sich durch eine LOX6 {\"U}berexpression das Metabolom {\"a}ndert, wurde eine „untargeted Analyse" mit 35SLOX6 Linien durchgef{\"u}hrt. Diese zeigte vier Metabolite, welche in den 35SLOX6 Linien im Vergleich zum Wildtyp unterschiedlich stark vorhanden waren. Zudem sollte untersucht werden, ob sich die Physiologie und Stressresistenz in den {\"U}berexpressionslinien im Vergleich zum Wildtyp unterscheiden. Dabei zeichneten sich die 35SLOX6 Linien durch kleinere, hellere und rundere Bl{\"a}tter aus. Zudem wurden die Wurzeln der 35SLOX6 Linien bei Fraßversuchen mit Pocellio scaber im Vergleich zum Wildtyp weniger bevorzugt gefressen. Diese Erkenntnisse sowie die generierten Konstrukte und Pflanzenlinien k{\"o}nnen in der Zukunft einen weiteren Einblick in die vielf{\"a}ltigen Funktionen und Produkte der LOX6 gew{\"a}hren.},
  subject      = {Jasmonate},
  language  = {de}
}
@phdthesis{Lind2016,
  author    = {Lind, Christof Martin},
  title     = {W{\"a}hrend der Evolution von Landpflanzen geriet der Anionenkanal SLAC1 unter die Kontrolle des ABA-Signalwegs},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-141669},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2016},
  abstract  = {Die ersten Landpflanzen standen vor der Herausforderung sich mit der wechselnden Verf{\"u}gbarkeit von Wasser an Land arrangieren zu m{\"u}ssen. Daraus ergab sich die Notwendigkeit den Wasserverlust zu minimieren und dennoch ausreichend CO2 f{\"u}r die Photosynthese aufzunehmen (Raven, 2002). Im Laufe der Evolution der Pflanzen entstanden mehrere Anpassungen an diese neuen Gegebenheiten, die schließlich auch zur Entstehung von regulierbaren {\"O}ffnungen, den Stomata, in der Blattepidermis f{\"u}hrte. Zwei Schließzellen umschließen das Stoma und regulieren {\"u}ber die Aufnahme oder Abgabe von osmotisch-aktiven Teilchen ihren Turgordruck und damit die {\"O}ffnungsweite des Stomas. Das Kation Kalium und die Anionen Chlorid und Nitrat repr{\"a}sentieren die Hauptosmotika, die je nach Bedarf durch Transportproteine {\"u}ber die Plasmamembran der Schließzellen geschleust werden. In den Samenpflanzen wie zum Beispiel der Modellpflanze Arabidopsis thaliana, ist der Signalweg in Schließzellen, der bei Trockenheit zu einem schnellen Schluss des Stomas f{\"u}hrt bereits sehr gut untersucht. Bei Wassermangel synthetisiert die Pflanze das Trockenstresshormon ABA (Abscisins{\"a}ure). Das Hormon wird durch ABA-Rezeptoren erkannt und resultiert schließlich in der Aktivit{\"a}t der Proteinkinase OST1. Daraufhin reguliert diese Kinase zum einen die Transkription ABA-abh{\"a}ngiger Gene, die der Pflanze eine langfristige Adaptation an Trockenheit und Austrocknungstoleranz verleiht. Zum anderen, phosphoryliert OST1 den Anionenkanal SLAC1 und aktiviert ihn so. Die Aktivit{\"a}t des Kanals initiiert schließlich den Stomaschluss durch einen Ausstrom von Anionen aus den Schließzellen, der mit einer Depolarisation der Schließzellmembran einhergeht. Der ABA-Signalweg, der zur transkriptionellen Regulation von Genen und der damit verbunden Trockentoleranz f{\"u}hrt ist ein sehr stark konservierter und evolutiv sehr alter Signalweg, der in allen Geweben von Pflanzen bei Trockenheit beschritten wird. Der schnelle ABA-Signalweg, der die Aktivit{\"a}t der SLAC1 Anionenkan{\"a}le reguliert, ist auf Schließzellen begrenzt. Da sich Schließzellen aber erst sp{\"a}t in der Evolution von Landpflanzen etablierten, erhob sich die Frage, wann in der Evolution geriet SLAC1 unter die Kontrolle das ABA-Signalwegs? Geht diese Regulation von SLAC1 mit der Entstehung von Schließzellen einher oder bestand dieser Regulationsmechanismus bereits in Pflanzen, die keine Schließzellen besitzen. Zur Beantwortung dieser Frage untersuchte ich die einzelnen Komponenten des Signalwegs und ihre Beziehungen zu einander im heterologen Expressionssystem der Xenopus laevis Oozyten. Im Laufe dieser Arbeit wurden Schl{\"u}sselelemente des ABA-Signalwegs aus sechs verschiedenen Versuchspflanzen kloniert und in Oozyten charakterisiert. F{\"u}r die Untersuchung der Evolution des schnellen ABA-Signalwegs wurden die sechs Versuchspflanzen aus je einem rezenten Vertreter der Gr{\"u}nalgen (Klebsormidium nitens), der Lebermoose (Marchantia polymorpha), der Laubmoose (Physcomitrella patens), der Lycophyten (Selaginella moellendorffii) und der Farne (Ceratopteris richardii) ausgew{\"a}hlt und mit der Samenpflanze Arabidopsis thaliana verglichen. Die sechs Pflanzengruppen spalteten sich an unterschiedlichen Zeitpunkten im Laufe der pflanzlichen Evolution von der Entwicklung der restlichen Pflanzen ab und erlauben so einen bestm{\"o}glichen Einblick in den jeweiligen Entwicklungsstand der Landpflanzen w{\"a}hrend der Entstehung der einzelnen Pflanzenfamilien. Obwohl sich die ersten Stomata erst in den Laubmoosen entwickelten, besitzen schon die Gr{\"u}nalgen OST1-Kinasen und SLAC1-Kan{\"a}le. Interessanterweise konnte wir zeigen, dass schon die fr{\"u}hen OST1-Kinasen aus Algen und Moosen dazu in der Lage sind, in den h{\"o}her entwickelten Samenpflanzen die Rolle in der Regulation der ABA-abh{\"a}ngigen Expression von Genen zu {\"u}bernehmen. Außerdem zeigte sich im Laufe meiner biophysikalischen Untersuchungen, dass alle dreizehn getesteten OST1-Kinasen aus den sechs unterschiedlichen Versuchspflanzenarten in Lage sind, den Anionenkanal SLAC1 aus Arabidopsis in Xenopus Oozyten zu aktivieren. Diese Austauschbarkeit von den AtSLAC1-aktivierenden Kinasen deutet auf eine sehr starke Konservierung der Struktur und Funktion von OST1 hin. Anders verhielt es sich bei der funktionellen Analyse der Anionenkan{\"a}le aus den verschiedenen Versuchspflanzen: Hier bildete nur der evolution{\"a}r gesehen j{\"u}ngsten SLAC-Kanal AtSLAC1 aus Arabidopsis ein funktionelles P{\"a}rchen mit OST1. Die SLAC1 Kan{\"a}le aus der Gr{\"u}nalge, dem Lebermoos, den Lycophyten und dem Farn blieben ohne messbare Aktivit{\"a}t bei einer Co-expression mit den verschiedenen OST1 Kinasen. Nur beim Laubmoos (Physcomitrella patens) konnte noch ein funktionelles Kinase-Anionenkanal P{\"a}rchen gefunden werden. Struktur-Funktionsuntersuchungen erlaubten mir schließlich zu zeigen, dass bestimmte funktionelle Dom{\"a}nen sowohl im N-terminus als auch im C-terminus von SLAC1 erforderlich sind, um eine Aktivierung des Kanals durch OST1 Kinasen sicherzustellen.},
  subject      = {Evolution},
  language  = {de}
}
@phdthesis{Muench2016,
  author    = {M{\"u}nch, Miriam},
  title     = {Funktionelle Untersuchungen zur Oxylipin-abh{\"a}ngigen Regulation von Hitzeschockproteinen in \(Arabidopsis\) \(thaliana\)},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-140299},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2016},
  abstract  = {Oxylipine sind Signalmolek{\"u}le, die durch enzymatische Oxidation oder durch Autoxidation von mehrfach unges{\"a}ttigten Fetts{\"a}uren entstehen. Sie akkumulieren w{\"a}hrend einer Vielzahl von biotischen und abiotischen Stressen und spielen eine bedeutende Rolle bei der Abwehr verschiedener Stressoren. In vielen physiologischen Entwicklungsprozessen sind Oxylipine ebenfalls wichtig. Eine bisher wenig erforschte Untergruppe dieser Oxylipine bilden reaktive elektrophile Spezies, die sog. RES-Oxylipine. Hierzu geh{\"o}ren unter anderem der Jasmons{\"a}ure-Vorl{\"a}ufer 12 Oxophytodiens{\"a}ure (OPDA), aber auch (E)-2-Hexenal oder Phytoprostan A1 (PPA1). Diese Substanzen sind aufgrund einer α,β unges{\"a}ttigten Carbonylgruppe elektrophil und damit chemisch reaktiv. Diese Reaktivit{\"a}t wird als Grund f{\"u}r ihre biologische Aktivit{\"a}t angesehen: RES-Oxylipine sind Induktoren einer Reihe von Genen. Allerdings ist bisher wenig {\"u}ber den Signalweg sowie die Funktionen der RES-Oxylipine in Arabidopsis thaliana bekannt. Fast die H{\"a}lfte (40 \%) aller durch OPDA-induzierten Gene in A. thaliana sind abh{\"a}ngig von TGA-Transkriptionsfaktoren, jedoch werden OPDA-responsive Hitzeschockgene (z.B. Hitzeschockproteine) unabh{\"a}ngig von TGA-Transkriptionsfaktoren induziert. Außerdem gibt es Hinweise auf eine Akkumulation des RES-Oxylipins OPDA, aber auch des non-RES-Oxylipins Jasmons{\"a}ure (JA) durch eine Behandlung mit 38° C in A. thaliana. Eine exogene Applikation von JA bewirkt jedoch, im Gegensatz zu OPDA, keine Genexpression von Hitzeschockgenen in Arabidopsis. Ziel dieser Arbeit war es, die Funktion der RES-Oxylipine OPDA und Prostaglandin A1 (PGA1, ein Analogon zu PPA1) w{\"a}hrend der Hitzeschockantwort in Arabidopsis thaliana, sowie die TGA-unabh{\"a}ngige Signaltransduktion der Hitzeschockgene, aufzukl{\"a}ren. Durch einen Vergleich zweier bereits ver{\"o}ffentlichter Transkriptomdaten in silico konnte die {\"U}berschneidung des Hitze-induzierten- (1 h, 37 °C) und des OPDA-induzierten-Transkriptoms (4 h, 75 µM) genau analysiert werden. Es werden 30 Gene sowohl von OPDA als auch durch 37 °C mehr als dreifach hochreguliert. Dieses Ergebnis konnte durch realtime qPCR vier repr{\"a}sentativer Gene (HSP101, HSP26.5, DREB2A, HSFA2) best{\"a}tigt werden. Allerdings zeigten sich deutliche Unterschiede in der St{\"a}rke und Kinetik der Induktion: Hitze (37 °C) hat einen sehr viel st{\"a}rkeren Einfluss auf die Hochregulation der Genexpression als die getesteten RES-Oxylipine OPDA und PGA1 (unter 10 \% der Induktion durch 37 °C, Ausnahme DREB2A). Zudem resultiert eine Hitzebehandlung in einer schnellen und transienten Genexpression, das Maximum ist nach 1 bis 2 h erreicht w{\"a}hrend die Addition von RES-Oxylipinen eine langsamere Induktion der Genexpression bewirkt (Maximum nach 4 bis 6 h). Eine Genexpressionsanalyse mit verschiedenen Signaltransduktionsmutanten half bei der Aufkl{\"a}rung m{\"o}glicher Signaltransduktionskomponenten der RES-Oxylipine. So konnte gezeigt werden, dass der putative OPDA-Rezeptor Cyclophilin 20-3 sowie sein Interaktionspartner, das Protein Serin-Acetyltransferase 1, keine Bedeutung in der Regulation von Hitzeschockgenen durch RES-Oxylipine haben. Die Hitze-Masterregulatoren HSFA1 a,b,d (und e) jedoch sind f{\"u}r die Induktion der Hitzeschockgene HSP101, HSP26.5 und HSFA2 durch RES-Oxylipine essentiell und f{\"u}r DREB2A zumindest teilweise notwendig. Dennoch spielt der durch Hitze induzierbare Transkriptionsfaktor HSFA2 in der Signaltransduktion von RES-Oxylipinen (bez{\"u}glich der Hitzeschockgeninduktion) keine Rolle. Durch ein Screening strukturell verschiedener RES hinsichtlich ihrer Induktion von HSP101 konnte gekl{\"a}rt werden, dass nicht die Anwesenheit einer α,β unges{\"a}ttigten Carbonylgruppe, sondern vielmehr die Eigenschaft der Elektrophilie f{\"u}r die Induktion des HSP101 verantwortlich ist. Auch das RES Sulforaphan vermittelt, wie die RES-Oxylipine OPDA und PGA1, die Induktion der Hitzeschockgene {\"u}ber die HSFA1-Transkritionsfaktoren. Ein weiterer Schwerpunkt dieser Arbeit lag in der Quantifizierung der endogenen Oxylipine in zehn Tage alten Arabidopsis-Keimligen nach einer Hitzebehandlung unter Kurztag-Lichtbedingungen. Weder w{\"a}hrend eines kurzzeitigen Hitzestresses (bis zu 8 h) noch w{\"a}hrend einer l{\"a}ngerfristigen Hitzebehandlung (bis zu 7 Tage) steigt der Gehalt des RES Oxylipins OPDA signifikant an. Das non-RES-Oxylipin Jasmons{\"a}ure hingegen akkumuliert transient (Maximum 2 h nach Beginn eines Hitzestresses) und signifikant, allerdings ist dieser Anstieg in seiner St{\"a}rke (13fach) nicht vergleichbar mit einer Akkumulation beispielsweise nach Verwundung (hier ist ein 1000facher Anstieg m{\"o}glich). In weiteren Experimenten wurde eine m{\"o}gliche Korrelation der endogenen Oxylipin-Akkumulation (verursacht durch Verwundung oder osmotischen Stress) mit der Genexpression von Hitzeschockgenen untersucht. …},
  subject      = {Schmalwand <Arabidopsis>},
  language  = {de}
}
@article{ZhuShabalaCuinetal.2016,
  author    = {Zhu, Min and Shabala, Lana and Cuin, Tracey A. and Huang, Xin and Zhou, Meixue and Munns, Rana and Shabala, Sergey},
  title     = {Nax loci affect SOS1-like Na\(^+\)/H\(^+\) exchanger expression and activity in wheat},
  series = {Journal of Experimental Botany},
  volume    = {67},
  journal   = {Journal of Experimental Botany},
  number    = {3},
  doi       = {10.1093/jxb/erv493},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-190908},
  pages     = {835-844},
  year      = {2016},
  abstract  = {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.},
  language  = {en}
}
@article{ChopraBiehlSteinfattetal.2016,
  author    = {Chopra, Martin and Biehl, Marlene and Steinfatt, Tim and Brandl, Andreas and Kums, Juliane and Amich, Jorge and Vaeth, Martin and Kuen, Janina and Holtappels, Rafaela and Podlech, J{\"u}rgen and Mottok, Anja and Kraus, Sabrina and Jord{\´a}n-Garotte, Ana-Laura and B{\"a}uerlein, Carina A. and Brede, Christian and Ribechini, Eliana and Fick, Andrea and Seher, Axel and Polz, Johannes and Ottmueller, Katja J. and Baker, Jeannette and Nishikii, Hidekazu and Ritz, Miriam and Mattenheimer, Katharina and Schwinn, Stefanie and Winter, Thorsten and Sch{\"a}fer, Viktoria and Krappmann, Sven and Einsele, Hermann and M{\"u}ller, Thomas D. and Reddehase, Matthias J. and Lutz, Manfred B. and M{\"a}nnel, Daniela N. and Berberich-Siebelt, Friederike and Wajant, Harald and Beilhack, Andreas},
  title     = {Exogenous TNFR2 activation protects from acute GvHD via host T reg cell expansion},
  series = {Journal of Experimental Medicine},
  volume    = {213},
  journal   = {Journal of Experimental Medicine},
  number    = {9},
  doi       = {10.1084/jem.20151563},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-187640},
  pages     = {1881-1900},
  year      = {2016},
  abstract  = {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.},
  language  = {en}
}
@article{HornKellerHildebrandtetal.2016,
  author    = {Horn, Hannes and Keller, Alexander and Hildebrandt, Ulrich and K{\"a}mpfer, Peter and Riederer, Markus and Hentschel, Ute},
  title     = {Draft genome of the \(Arabidopsis\) \(thaliana\) phyllosphere bacterium, \(Williamsia\) sp. ARP1},
  series = {Standards in Genomic Sciences},
  volume    = {11},
  journal   = {Standards in Genomic Sciences},
  number    = {8},
  doi       = {10.1186/s40793-015-0122-x},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-146008},
  year      = {2016},
  abstract  = {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.},
  language  = {en}
}
@article{BoehmScherzerKroletal.2016,
  author    = {B{\"o}hm, Jennifer and Scherzer, S{\"o}nke and Krol, Elzbieta and Kreuzer, Ines and von Meyer, Katharina and Lorey, Christian and Mueller, Thomas D. and Shabala, Lana and Monte, Isabel and Salano, Roberto and Al-Rasheid, Khaled A. S. and Rennenberg, Heinz and Shabala, Sergey and Neher, Erwin and Hedrich, Rainer},
  title     = {The Venus Flytrap Dionaea muscipula Counts Prey-Induced Action Potentials to Induce Sodium Uptake},
  series = {Current Biology},
  volume    = {26},
  journal   = {Current Biology},
  number    = {3},
  doi       = {10.1016/j.cub.2015.11.057},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-128054},
  pages     = {286-295},
  year      = {2016},
  abstract  = {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.},
  subject      = {Venusfliegenfalle},
  language  = {en}
}
@phdthesis{Asmus2016,
  author    = {Asmus, Elisabeth},
  title     = {Mode of Action of Adjuvants for Foliar Application},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-138159},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2016},
  abstract  = {Adjuvants are compounds added to an agrochemical spray formulation to improve or modify the action of an active ingredient (AI) or the physico-chemical characteristics of the spray liquid. Adjuvants can have more than only one distinct mode of action (MoA) during the foliar spray application process and they are generally known to be the best tools to improve agrochemical formulations. The main objective for this work was to elucidate the basic MoA of adjuvants by uncoupling different aspects of the spray application. Laboratory experiments, beginning from retention and spreading characteristics, followed by humectant effects concerning the spray deposit on the leaf surface and ultimately the cuticular penetration of an AI, were figured out to evaluate overall in vivo effects of adjuvants which were also obtained in a greenhouse spray test. For this comprehensive study, the surfactant classes of non-ionic sorbitan esters (Span), polysorbates (Tween) and oleyl alcohol polyglycol ether (Genapol O) were generally considered because of their common promoting potential in agrochemical formulations and their structural diversity. The reduction of interfacial tension is one of the most crucial physico-chemical properties of surfactants. The dynamic surface tension (DST) was monitored to characterise the surface tension lowering behaviour which is known to influence the droplet formation and retention characteristics. The DST is a function of time and the critical time frame of droplet impact might be at about 100 ms. None of the selected surfactants were found to lower the surface tension sufficiently during this short timeframe (chapter I). At ca. 100 ms, Tween 20 resulted in the lowest DST value. When surfactant monomers are fully saturated at the droplet-air-interface, an equilibrium surface tension (STeq) value can be determined which may be used to predict spreading or run-off effects. The majority of selected surfactants resulted in a narrow distribution of STeq values, ranging between 30 and 45 mN m- 1. Nevertheless, all surfactants were able to decrease the surface tension considerably compared to pure water (72 mN m- 1). The influence of different surfactants on the wetting process was evaluated by studying time-dependent static contact angles on different surfaces and the droplet spread area on Triticum aestivum leaves after water evaporation. The spreading potential was observed to be better for Spans than for Tweens. Especially Span 20 showed maximum spreading results. To transfer laboratory findings to spray application, related to field conditions, retention and leaf coverage was measured quantitatively on wheat leaves by using a variable track sprayer. Since the retention process involves short time dynamics, it is well-known that the spray retention on a plant surface is not correlated to STeq but to DST values. The relationship between DST at ca. 100 ms and results from the track sprayer showed increasing retention results with decreasing DST, whereas at DST values below ca. 60 mN m- 1 no further retention improvement could be observed. Under field conditions, water evaporates from the droplet within a few seconds to minutes after droplet deposition on the leaf surface. Since precipitation of the AI must essentially being avoided by holding the AI in solution, so-called humectants are used as tank-mix adjuvants. The ability of pure surfactants to absorb water from the surrounding atmosphere was investigated comprehensively by analysing water sorption isotherms (chapter II). These isotherms showed an exponential shape with a steep water sorption increase starting at 60\% to 70\% RH. Water sorption was low for Spans and much more distinct for the polyethoxylated surfactants (Tweens and Genapol O series). The relationship between the water sorption behaviour and the molecular structure of surfactants was considered as the so-called humectant activity. With an increasing ethylene oxide (EO) content, the humectant activity increased concerning the particular class of Genapol O. However, it could be shown that the moisture absorption across all classes of selected surfactants correlates rather better with their hydrophilic-lipophilic balance values with the EO content. All aboveground organs of plants are covered by the cuticular membrane which is therefore the first rate limiting barrier for AI uptake. In vitro penetration experiments through an astomatous model cuticle were performed to study the effects of adjuvants on the penetration of the lipophilic herbicide Pinoxaden (PXD) (chapter III). In order to understand the influence of different adjuvant MoA like humectancy, experiments were performed under three different humidity levels. No explicit relationship could be found between humidity levels and the PXD penetration which might be explained by the fact that humidity effects would rather affect hydrophilic AIs than lipophilic ones. Especially for Tween 20, it became obvious that a complex balance between multiple MoA like spreading, humectancy and plasticising effects have to be considered. Greenhouse trials, focussing the adjuvant impact on in vivo action of PXD, were evaluated on five different grass-weed species (chapter III). Since agrochemical spray application and its following action on living plants also includes translocation processes in planta and species dependent physiological effects, this investigation may help to simulate the situation on the field. Even though the absolute weed damage was different, depending both on plant species and also on PXD rates, adjuvant effects in greenhouse experiments displayed the same ranking as in cuticular penetration studies: Tween 20 > Tween 80 > Span 20 ≥ Span 80. Thus, the present work shows for the first time that findings obtained in laboratory experiments can be successfully transferred to spray application studies on living plants concerning adjuvant MoA. A comparative analysis, using radar charts, could demonstrate systematic derivations from structural similarities of adjuvants to their MoA (summarising discussion and outlook). Exemplarily, Tween 20 and Tween 80 cover a wide range of selected variables by having no outstanding MoA improving one distinct process during foliar application, compared to non-ethoxylated Span 20 and Span 80 which primarily revealed a surface active action. Most adjuvants used in this study represent polydisperse mixtures bearing a complex distribution of EO and aliphatic chains. From this study it seems alike that adjuvants having a wide EO distribution offer broader potential than adjuvants with a small EO distribution. It might be a speculation that due to this broad distribution of single molecules, all bearing their individual specific physico-chemical nature, a wide range of properties concerning their MoA is covered.},
  subject      = {Adjuvans},
  language  = {en}
}
@article{JoensuuAltimirHakolaetal.2016,
  author    = {Joensuu, Johanna and Altimir, Nuria and Hakola, Hannele and Rost{\´a}s, Michael and Raivonen, Maarit and Vestenius, Mika and Aaltonen, Hermanni and Riederer, Markus and B{\"a}ck, Jaana},
  title     = {Role of needle surface waxes in dynamic exchange of mono- and sesquiterpenes},
  series = {Atmospheric Chemistry and Physics},
  volume    = {16},
  journal   = {Atmospheric Chemistry and Physics},
  doi       = {10.5194/acp-16-7813-2016},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-198547},
  pages     = {7813-7823},
  year      = {2016},
  abstract  = {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.},
  language  = {en}
}
@article{BoehmScherzerKroletal.2016,
  author    = {B{\"o}hm, Jennifer and Scherzer, S{\"o}nke and Krol, Elzbieta and Kreuzer, Ines and von Meyer, Katharina and Lorey, Christian and Mueller, Thomas D. and Shabala, Lana and Monte, Isabel and Solano, Roberto and Al-Rasheid, Khaled A. S. and Rennenberg, Heinz and Shabala, Sergey and Neher, Erwin and Hedrich, Rainer},
  title     = {The Venus flytrap Dionaea muscipula counts prey-induced action potentials to induce sodium uptake},
  series = {Current Biology},
  volume    = {26},
  journal   = {Current Biology},
  number    = {3},
  doi       = {10.1016/j.cub.2015.11.057},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-190870},
  pages     = {286-295},
  year      = {2016},
  abstract  = {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.},
  language  = {en}
}
@article{NukarinenNaegelePedrottietal.2016,
  author    = {Nukarinen, Ella and N{\"a}gele, Thomas and Pedrotti, Lorenzo and Wurzinger, Bernhard and Mair, Andrea and Landgraf, Ramona and B{\"o}rnke, Frederik and Hanson, Johannes and Teige, Markus and Baena-Gonzalez, Elena and Dr{\"o}ge-Laser, Wolfgang and Weckwerth, Wolfram},
  title     = {Quantitative phosphoproteomics reveals the role of the AMPK plant ortholog SnRK1 as a metabolic master regulator under energy deprivation},
  series = {Scientific Reports},
  volume    = {6},
  journal   = {Scientific Reports},
  number    = {31697},
  doi       = {10.1038/srep31697},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-167638},
  year      = {2016},
  abstract  = {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.},
  language  = {en}
}
@article{BhavsarSinghSharmaetal.2016,
  author    = {Bhavsar, Shefalee K. and Singh, Yogesh and Sharma, Piyush and Khairnar, Vishal and Hosseinzadeh, Zohreh and Zhang, Shaqiu and Palmada, Monica and Sabolic, Ivan and Koepsell, Hermann and Lang, Karl S. and Lang, Philipp A. and Lang, Florian},
  title     = {Expression of JAK3 Sensitive Na\(^+\) Coupled Glucose Carrier SGLT1 in Activated Cytotoxic T Lymphocytes},
  series = {Cellular Physiology and Biochemistry},
  volume    = {39},
  journal   = {Cellular Physiology and Biochemistry},
  number    = {3},
  doi       = {10.1159/000447827},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-164900},
  pages     = {1209-1228},
  year      = {2016},
  abstract  = {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.},
  language  = {en}
}
@article{BoschertFrischBacketal.2016,
  author    = {Boschert, V. and Frisch, C. and Back, J. W. and van Pee,, K. and Weidauer, S. E. and Muth, E.-M. and Schmieder, P. and Beerbaum, M. and Knappik, A. and Timmerman, P. and Mueller, T. D.},
  title     = {The sclerostin-neutralizing antibody AbD09097 recognizes an epitope adjacent to sclerostin's binding site for the Wnt co-receptor LRP6},
  series = {Open Biology},
  volume    = {6},
  journal   = {Open Biology},
  doi       = {10.1098/rsob.160120},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-177925},
  year      = {2016},
  abstract  = {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.},
  language  = {en}
}
@article{BoehmScherzerShabalaetal.2016,
  author    = {B{\"o}hm, J. and Scherzer, S. and Shabala, S. and Krol, E. and Neher, E. and Mueller, T. D. and Hedrich, R.},
  title     = {Venus flytrap HKT1-type channel provides for prey sodium uptake into carnivorous plant without conflicting with electrical excitability},
  series = {Molecular Plant},
  volume    = {9},
  journal   = {Molecular Plant},
  number    = {3},
  doi       = {10.1016/j.molp.2015.09.017},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-189803},
  pages     = {428-436},
  year      = {2016},
  abstract  = {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.},
  language  = {en}
}
@article{KlughammerSchreiber2016,
  author    = {Klughammer, Christof and Schreiber, Ulrich},
  title     = {Deconvolution of ferredoxin, plastocyanin, and P700 transmittance changes in intact leaves with a new type of kinetic LED array spectrophotometer},
  series = {Photosynthesis Research},
  volume    = {128},
  journal   = {Photosynthesis Research},
  number    = {2},
  doi       = {10.1007/s11120-016-0219-0},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-189050},
  pages     = {195-214},
  year      = {2016},
  abstract  = {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.},
  language  = {en}
}
@article{CicovaDejungSkalickyetal.2016,
  author    = {Cicova, Zdenka and Dejung, Mario and Skalicky, Tomas and Eisenhuth, Nicole and Hanselmann, Steffen and Morriswood, Brooke and Figueiredo, Luisa M. and Butter, Falk and Janzen, Christian J.},
  title     = {Two flagellar BAR domain proteins in Trypanosoma brucei with stage-specific regulation},
  series = {Scientific Reports},
  volume    = {6},
  journal   = {Scientific Reports},
  doi       = {10.1038/srep35826},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-181021},
  year      = {2016},
  abstract  = {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.},
  language  = {en}
}
@article{JakobsonVaahteraToldseppetal.2016,
  author    = {Jakobson, Liina and Vaahtera, Lauri and T{\~o}ldsepp, Kadri and Nuhkat, Maris and Wang, Cun and Wang, Yuh-Shuh and H{\~o}rak, Hanna and Valk, Ervin and Pechter, Priit and Sindarovska, Yana and Tang, Jing and Xiao, Chuanlei and Xu, Yang and Talas, Ulvi Gerst and Garc{\´i}a-Sosa, Alfonso T. and Kangasj{\"a}rvi, Saijaliisa and Maran, Uko and Remm, Maido and Roelfsema, M. Rob G. and Hu, Honghong and Kangasj{\"a}rvi, Jaakko and Loog, Mart and Schroeder, Julian I. and Kollist, Hannes and Brosch{\´e}, Mikael},
  title     = {Natural Variation in Arabidopsis Cvi-0 Accession Reveals an Important Role of MPK12 in Guard Cell CO\(_{2}\) Signaling},
  series = {PLoS Biology},
  volume    = {14},
  journal   = {PLoS Biology},
  number    = {12},
  doi       = {10.1371/journal.pbio.2000322},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-166657},
  pages     = {e2000322},
  year      = {2016},
  abstract  = {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.},
  language  = {en}
}
@article{ShepardChevalPeterlinetal.2016,
  author    = {Shepard, Blythe D. and Cheval, Lydie and Peterlin, Zita and Firestein, Stuart and Koepsell, Hermann and Doucet, Alain and Pluznick, Jennifer L.},
  title     = {A Renal Olfactory Receptor Aids in Kidney Glucose Handling},
  series = {Scientific Reports},
  volume    = {6},
  journal   = {Scientific Reports},
  number    = {35215},
  doi       = {10.1038/srep35215},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-167605},
  year      = {2016},
  abstract  = {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.},
  language  = {en}
}
@article{GalloWardFotheringhametal.2016,
  author    = {Gallo, Linda A. and Ward, Micheal S. and Fotheringham, Amelia K. and Zhuang, Aowen and Borg, Danielle J. and Flemming, Nicole B. and Harvie, Ben M. and Kinneally, Toni L. and Yeh, Shang-Ming and McCarthy, Domenica A. and Koepsell, Hermann and Vallon, Volker and Pollock, Carol and Panchapakesan, Usha and Forbes, Josephine M.},
  title     = {Once daily administration of the SGLT2 inhibitor, empagliflozin, attenuates markers of renal fibrosis without improving albuminuria in diabetic db/db mice},
  series = {Scientific Reports},
  volume    = {6},
  journal   = {Scientific Reports},
  number    = {26428},
  doi       = {10.1038/srep26428},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-167678},
  year      = {2016},
  abstract  = {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.},
  language  = {en}
}
@article{SchusterBurghardtAlfarhanetal.2016,
  author    = {Schuster, Ann-Christin and Burghardt, Markus and Alfarhan, Ahmed and Bueno, Amauri and Hedrich, Rainer and Leide, Jana and Thomas, Jacob and Riederer, Markus},
  title     = {Effectiveness of cuticular transpiration barriers in a desert plant at controlling water loss at high temperatures},
  series = {AoB Plants},
  volume    = {8},
  journal   = {AoB Plants},
  doi       = {10.1093/aobpla/plw027},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-160963},
  pages     = {plw027},
  year      = {2016},
  abstract  = {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.},
  language  = {en}
}
@article{JahnMarkertRyuetal.2016,
  author    = {Jahn, Martin T. and Markert, Sebastian M. and Ryu, Taewoo and Ravasi, Timothy and Stigloher, Christian and Hentschel, Ute and Moitinho-Silva, Lucas},
  title     = {Shedding light on cell compartmentation in the candidate phylum Poribacteria by high resolution visualisation and transcriptional profiling},
  series = {Scientific Reports},
  volume    = {6},
  journal   = {Scientific Reports},
  number    = {35860},
  doi       = {10.1038/srep35860},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-167513},
  year      = {2016},
  abstract  = {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.},
  language  = {en}
}