TY - JOUR A1 - Aso, Yoshinori A1 - Herb, Andrea A1 - Ogueta, Maite A1 - Siwanowicz, Igor A1 - Templier, Thomas A1 - Friedrich, Anja B. A1 - Ito, Kei A1 - Scholz, Henrike A1 - Tanimoto, Hiromu T1 - Three Dopamine Pathways Induce Aversive Odor Memories with Different Stability JF - PLoS Genetics N2 - Animals acquire predictive values of sensory stimuli through reinforcement. In the brain of Drosophila melanogaster, activation of two types of dopamine neurons in the PAM and PPL1 clusters has been shown to induce aversive odor memory. Here, we identified the third cell type and characterized aversive memories induced by these dopamine neurons. These three dopamine pathways all project to the mushroom body but terminate in the spatially segregated subdomains. To understand the functional difference of these dopamine pathways in electric shock reinforcement, we blocked each one of them during memory acquisition. We found that all three pathways partially contribute to electric shock memory. Notably, the memories mediated by these neurons differed in temporal stability. Furthermore, combinatorial activation of two of these pathways revealed significant interaction of individual memory components rather than their simple summation. These results cast light on a cellular mechanism by which a noxious event induces different dopamine signals to a single brain structure to synthesize an aversive memory. KW - dynamics KW - serotonin KW - expression KW - melanogaster KW - neurons form KW - olfactory memory KW - long-term-memory KW - drosophila mushroom body KW - sensitization KW - localization Y1 - 2012 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-130631 VL - 8 IS - 7 ER - TY - JOUR A1 - Huser, Annina A1 - Rohwedder, Astrid A1 - Apostolopoulou, Anthi A. A1 - Widmann, Annekathrin A1 - Pfitzenmaier, Johanna E. A1 - Maiolo, Elena M. A1 - Selcho, Mareike A1 - Pauls, Dennis A1 - von Essen, Alina A1 - Gupta, Tript A1 - Sprecher, Simon G. A1 - Birman, Serge A1 - Riemensperger, Thomas A1 - Stocker, Reinhard F. A1 - Thum, Andreas S. T1 - The Serotonergic Central Nervous System of the Drosophila Larva: Anatomy and Behavioral Function JF - PLoS One N2 - The Drosophila larva has turned into a particularly simple model system for studying the neuronal basis of innate behaviors and higher brain functions. Neuronal networks involved in olfaction, gustation, vision and learning and memory have been described during the last decade, often up to the single-cell level. Thus, most of these sensory networks are substantially defined, from the sensory level up to third-order neurons. This is especially true for the olfactory system of the larva. Given the wealth of genetic tools in Drosophila it is now possible to address the question how modulatory systems interfere with sensory systems and affect learning and memory. Here we focus on the serotonergic system that was shown to be involved in mammalian and insect sensory perception as well as learning and memory. Larval studies suggested that the serotonergic system is involved in the modulation of olfaction, feeding, vision and heart rate regulation. In a dual anatomical and behavioral approach we describe the basic anatomy of the larval serotonergic system, down to the single-cell level. In parallel, by expressing apoptosis-inducing genes during embryonic and larval development, we ablate most of the serotonergic neurons within the larval central nervous system. When testing these animals for naive odor, sugar, salt and light perception, no profound phenotype was detectable; even appetitive and aversive learning was normal. Our results provide the first comprehensive description of the neuronal network of the larval serotonergic system. Moreover, they suggest that serotonin per se is not necessary for any of the behaviors tested. However, our data do not exclude that this system may modulate or fine-tune a wide set of behaviors, similar to its reported function in other insect species or in mammals. Based on our observations and the availability of a wide variety of genetic tools, this issue can now be addressed. KW - term memory KW - light avoidance KW - decision making KW - olfactory memory KW - immunoreactive neurons KW - containing neurons KW - moth manduca sexta KW - head involution KW - mushroom bodies KW - biogenic amines Y1 - 2012 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-130437 VL - 7 IS - 10 ER - TY - JOUR A1 - Naseem, Muhammad A1 - Dandekar, Thomas T1 - The Role of Auxin-Cytokinin Antagonism in Plant-Pathogen Interactions JF - PLOS Pathogens N2 - No abstract available. KW - disease KW - pseudomas-syringae KW - arabidpsis thaliana KW - immunity KW - organogenesis KW - transcription KW - resistance KW - crosstalk Y1 - 2012 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-131901 VL - 8 IS - 11 ER - TY - JOUR A1 - Rhiem, Kerstin A1 - Engel, Christoph A1 - Graeser, Monika A1 - Zachariae, Silke A1 - Kast, Karin A1 - Kiechle, Marion A1 - Ditsch, Nina A1 - Janni, Wolfgang A1 - Mundhenke, Christoph A1 - Golatta, Michael A1 - Varga, Dominic A1 - Preisler-Adams, Sabine A1 - Heinrich, Tilman A1 - Bick, Ulrich A1 - Gadzicki, Dorothea A1 - Briest, Susanne A1 - Meindl, Alfons A1 - Schmutzler, Rita K. T1 - The risk of contralateral breast cancer in patients from BRCA1/2 negative high risk families as compared to patients from BRCA1 or BRCA2 positive families: a retrospective cohort study JF - Breast Cancer Research N2 - Introduction: While it has been reported that the risk of contralateral breast cancer in patients from BRCA1 or BRCA2 positive families is elevated, little is known about contralateral breast cancer risk in patients from high risk families that tested negative for BRCA1/2 mutations. Methods: A retrospective, multicenter cohort study was performed from 1996 to 2011 and comprised 6,235 women with unilateral breast cancer from 6,230 high risk families that had tested positive for BRCA1 (n = 1,154) or BRCA2 (n = 575) mutations or tested negative (n = 4,501). Cumulative contralateral breast cancer risks were calculated using the Kaplan-Meier product-limit method and were compared between groups using the log-rank test. Cox regression analysis was applied to assess the impact of the age at first breast cancer and the familial history stratified by mutation status. Results: The cumulative risk of contralateral breast cancer 25 years after first breast cancer was 44.1% (95%CI, 37.6% to 50.6%) for patients from BRCA1 positive families, 33.5% (95%CI, 22.4% to 44.7%) for patients from BRCA2 positive families and 17.2% (95%CI, 14.5% to 19.9%) for patients from families that tested negative for BRCA1/2 mutations. Younger age at first breast cancer was associated with a higher risk of contralateral breast cancer. For women who had their first breast cancer before the age of 40 years, the cumulative risk of contralateral breast cancer after 25 years was 55.1% for BRCA1, 38.4% for BRCA2, and 28.4% for patients from BRCA1/2 negative families. If the first breast cancer was diagnosed at the age of 50 or later, 25-year cumulative risks were 21.6% for BRCA1, 15.5% for BRCA2, and 12.9% for BRCA1/2 negative families. Conclusions: Contralateral breast cancer risk in patients from high risk families that tested negative for BRCA1/2 mutations is similar to the risk in patients with sporadic breast cancer. Thus, the mutation status should guide decision making for contralateral mastectomy. KW - contralateral breast cancer KW - BRCA1/2 negative KW - BRCA1 positive KW - BRCA2 positive Y1 - 2012 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-135715 VL - 14 IS - 6 ER - TY - JOUR A1 - Merget, Benjamin A1 - Koetschan, Christian A1 - Hackl, Thomas A1 - Förster, Frank A1 - Dandekar, Thomas A1 - Müller, Tobias A1 - Schultz, Jörg A1 - Wolf, Matthias T1 - The ITS2 Database JF - Journal of Visual Expression N2 - The internal transcribed spacer 2 (ITS2) has been used as a phylogenetic marker for more than two decades. As ITS2 research mainly focused on the very variable ITS2 sequence, it confined this marker to low-level phylogenetics only. However, the combination of the ITS2 sequence and its highly conserved secondary structure improves the phylogenetic resolution1 and allows phylogenetic inference at multiple taxonomic ranks, including species delimitation. The ITS2 Database presents an exhaustive dataset of internal transcribed spacer 2 sequences from NCBI GenBank accurately reannotated. Following an annotation by profile Hidden Markov Models (HMMs), the secondary structure of each sequence is predicted. First, it is tested whether a minimum energy based fold (direct fold) results in a correct, four helix conformation. If this is not the case, the structure is predicted by homology modeling. In homology modeling, an already known secondary structure is transferred to another ITS2 sequence, whose secondary structure was not able to fold correctly in a direct fold. The ITS2 Database is not only a database for storage and retrieval of ITS2 sequence-structures. It also provides several tools to process your own ITS2 sequences, including annotation, structural prediction, motif detection and BLAST search on the combined sequence-structure information. Moreover, it integrates trimmed versions of 4SALE and ProfDistS for multiple sequence-structure alignment calculation and Neighbor Joining tree reconstruction. Together they form a coherent analysis pipeline from an initial set of sequences to a phylogeny based on sequence and secondary structure. In a nutshell, this workbench simplifies first phylogenetic analyses to only a few mouse-clicks, while additionally providing tools and data for comprehensive large-scale analyses. KW - homology modeling KW - molecular systematics KW - internal transcribed spacer 2 KW - alignment KW - genetics KW - secondary structure KW - ribosomal RNA KW - phylogenetic tree KW - phylogeny Y1 - 2012 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-124600 VL - 61 IS - e3806 ER - TY - JOUR A1 - Heisig, Julia A1 - Weber, David A1 - Englberger, Eva A1 - Winkler, Anja A1 - Kneitz, Susanne A1 - Sung, Wing-Kin A1 - Wolf, Elmar A1 - Eilers, Martin A1 - Wei, Chia-Lin A1 - Gessler, Manfred T1 - Target Gene Analysis by Microarrays and Chromatin Immunoprecipitation Identifies HEY Proteins as Highly Redundant bHLH Repressors N2 - HEY bHLH transcription factors have been shown to regulate multiple key steps in cardiovascular development. They can be induced by activated NOTCH receptors, but other upstream stimuli mediated by TGFß and BMP receptors may elicit a similar response. While the basic and helix-loop-helix domains exhibit strong similarity, large parts of the proteins are still unique and may serve divergent functions. The striking overlap of cardiac defects in HEY2 and combined HEY1/HEYL knockout mice suggested that all three HEY genes fulfill overlapping function in target cells. We therefore sought to identify target genes for HEY proteins by microarray expression and ChIPseq analyses in HEK293 cells, cardiomyocytes, and murine hearts. HEY proteins were found to modulate expression of their target gene to a rather limited extent, but with striking functional interchangeability between HEY factors. Chromatin immunoprecipitation revealed a much greater number of potential binding sites that again largely overlap between HEY factors. Binding sites are clustered in the proximal promoter region especially of transcriptional regulators or developmental control genes. Multiple lines of evidence suggest that HEY proteins primarily act as direct transcriptional repressors, while gene activation seems to be due to secondary or indirect effects. Mutagenesis of putative DNA binding residues supports the notion of direct DNA binding. While class B E-box sequences (CACGYG) clearly represent preferred target sequences, there must be additional and more loosely defined modes of DNA binding since many of the target promoters that are efficiently bound by HEY proteins do not contain an Ebox motif. These data clearly establish the three HEY bHLH factors as highly redundant transcriptional repressors in vitro and in vivo, which explains the combinatorial action observed in different tissues with overlapping expression. KW - Biologie Y1 - 2012 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-75341 ER - TY - JOUR A1 - Hsieh, Yu-Lung A1 - Linsenmair, Karl Eduard T1 - Seasonal dynamics of arboreal spider diversity in a temperate forest N2 - Measuring and estimating biodiversity patterns is a fundamental task of the scientist working to support conservation and informmanagement decisions.Most biodiversity studies in temperate regions were often carried out over a very short period of time (e.g., a single season) and it is often—at least tacitly—assumed that these short-termfindings are representative of long-termgeneral patterns.However, should the studied biodiversity pattern in fact contain significant temporal dynamics, perhaps leading to contradictory conclusions. Here, we studied the seasonal diversity dynamics of arboreal spider communities dwelling in 216 European beeches (Fagus sylvatica L.) to assess the spider community composition in the following seasons: two cold seasons (I:November 2005–January 2006; II: February–April) and two warm seasons (III: May–July; IV: August–October). We show that the usually measured diversity of the warmseason community (IV: 58 estimated species) alone did not deliver a reliable image of the overall diversity present in these trees, and therefore, we recommend it should not be used for sampling protocols aimed at providing a full picture of a forest’s biodiversity in the temperate zones. In particular, when the additional samplings of other seasons (I, II, III) were included, the estimated species richness nearly doubled (108). Community I possessed the lowest diversity and evenness due to the harsh winter conditions: this community was comprised of one dominant species together with several species low in abundance. Similarity was lowest (38.6%) between seasonal communities I and III, indicating a significant species turnover due to recolonization, so that community III had the highest diversity. Finally, using nonparametric estimators, we found that further sampling in late winter (February–April) is most needed to complete our inventory. Our study clearly demonstrates that seasonal dynamics of communities should be taken into account when studying biodiversity patterns of spiders, and probably forest arthropods in general. KW - Biologie KW - Araneae KW - canopy fogging KW - European beech KW - recolonization KW - species richness estimation KW - true diversity Y1 - 2012 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-75158 ER - TY - JOUR A1 - Dandekar, Thomas A1 - Fieselmann, Astrid A1 - Popp, Jasmin A1 - Hensel, Michael T1 - Salmonella enterica: a surprisingly well-adapted intracellular lifestyle JF - Frontiers in Microbiology N2 - The infectious intracellular lifestyle of Salmonella enterica relies on the adaptation to nutritional conditions within the Salmonella-containing vacuole (SCV) in host cells. We summarize latest results on metabolic requirements for Salmonella during infection. This includes intracellular phenotypes of mutant strains based on metabolic modeling and experimental tests, isotopolog profiling using (13)C-compounds in intracellular Salmonella, and complementation of metabolic defects for attenuated mutant strains towards a comprehensive understanding of the metabolic requirements of the intracellular lifestyle of Salmonella. Helpful for this are also genomic comparisons. We outline further recent studies and which analyses of intracellular phenotypes and improved metabolic simulations were done and comment on technical required steps as well as progress involved in the iterative refinement of metabolic flux models, analyses of mutant phenotypes, and isotopolog analyses. Salmonella lifestyle is well-adapted to the SCV and its specific metabolic requirements. Salmonella metabolism adapts rapidly to SCV conditions, the metabolic generalist Salmonella is quite successful in host infection. KW - Salmonella enterica KW - metabolism KW - Salmonella-containing vacuole KW - regulation KW - virulence Y1 - 2012 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-123135 ER - TY - JOUR A1 - Schneider, Christof W. A1 - Tautz, Jürgen A1 - Grünewald, Bernd A1 - Fuchs, Stefan T1 - RFID Tracking of Sublethal Effects of Two Neonicotinoid Insecticides on the Foraging Behavior of Apis mellifera JF - PLoS One N2 - The development of insecticides requires valid risk assessment procedures to avoid causing harm to beneficial insects and especially to pollinators such as the honeybee Apis mellifera. In addition to testing according to current guidelines designed to detect bee mortality, tests are needed to determine possible sublethal effects interfering with the animal's vitality and behavioral performance. Several methods have been used to detect sublethal effects of different insecticides under laboratory conditions using olfactory conditioning. Furthermore, studies have been conducted on the influence insecticides have on foraging activity and homing ability which require time-consuming visual observation. We tested an experimental design using the radiofrequency identification (RFID) method to monitor the influence of sublethal doses of insecticides on individual honeybee foragers on an automated basis. With electronic readers positioned at the hive entrance and at an artificial food source, we obtained quantifiable data on honeybee foraging behavior. This enabled us to efficiently retrieve detailed information on flight parameters. We compared several groups of bees, fed simultaneously with different dosages of a tested substance. With this experimental approach we monitored the acute effects of sublethal doses of the neonicotinoids imidacloprid (0.15-6 ng/bee) and clothianidin (0.05-2 ng/bee) under field-like circumstances. At field-relevant doses for nectar and pollen no adverse effects were observed for either substance. Both substances led to a significant reduction of foraging activity and to longer foraging flights at doses of >= 0.5 ng/bee (clothianidin) and >= 1.5 ng/bee (imidacloprid) during the first three hours after treatment. This study demonstrates that the RFID-method is an effective way to record short-term alterations in foraging activity after insecticides have been administered once, orally, to individual bees. We contribute further information on the understanding of how honeybees are affected by sublethal doses of insecticides. KW - memory KW - nicotinic acetylcholine-receptors KW - unpaired median neurons KW - honey bees KW - learning performances KW - toxicity KW - hymenoptera KW - pesticides KW - relevance KW - agonist Y1 - 2012 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-131753 VL - 7 IS - 1 ER - TY - JOUR A1 - Sanges, C. A1 - Scheuermann, C. A1 - Zahedi, R. P. A1 - Sickmann, A. A1 - Lamberti, A. A1 - Migliaccio, N. A1 - Baljuls, A. A1 - Marra, M. A1 - Zappavigna, S. A1 - Rapp, U. A1 - Abbruzzese, A. A1 - Caraglia, M. A1 - Arcari, P. T1 - Raf kinases mediate the phosphorylation of eukaryotic translation elongation factor 1A and regulate its stability in eukaryotic cells JF - Cell Death & Disease N2 - We identified eukaryotic translation elongation factor 1A (eEF1A) Raf-mediated phosphorylation sites and defined their role in the regulation of eEF1A half-life and of apoptosis of human cancer cells. Mass spectrometry identified in vitro S21 and T88 as phosphorylation sites mediated by B-Raf but not C-Raf on eEF1A1 whereas S21 was phosphorylated on eEF1A2 by both B-and C-Raf. Interestingly, S21 belongs to the first eEF1A GTP/GDP-binding consensus sequence. Phosphorylation of S21 was strongly enhanced when both eEF1A isoforms were preincubated prior the assay with C-Raf, suggesting that the eEF1A isoforms can heterodimerize thus increasing the accessibility of S21 to the phosphate. Overexpression of eEF1A1 in COS 7 cells confirmed the phosphorylation of T88 also in vivo. Compared with wt, in COS 7 cells overexpressed phosphodeficient (A) and phospho-mimicking (D) mutants of eEF1A1 (S21A/D and T88A/D) and of eEF1A2 (S21A/D), resulted less stable and more rapidly proteasome degraded. Transfection of S21 A/D eEF1A mutants in H1355 cells increased apoptosis in comparison with the wt isoforms. It indicates that the blockage of S21 interferes with or even supports C-Raf induced apoptosis rather than cell survival. Raf-mediated regulation of this site could be a crucial mechanism involved in the functional switching of eEF1A between its role in protein biosynthesis and its participation in other cellular processes. KW - signal transduction KW - mass spectrometry KW - elongation KW - protein docking KW - factor EEF1A2 KW - cancer-cells KW - lung cancer KW - EF-1A KW - Raf kinases KW - aminoacyl-transfer-RNA KW - tyrosine phosphorylation KW - factor 1-alpha KW - nucleotide exchange KW - polyarcylamide gels KW - chain KW - apoptosis KW - ubiquitin Y1 - 2012 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-134673 VL - 3 IS - e276 ER -