Project description:The centromere-specific Histone H3-variant CENH3 (also known as CENP-A) is considered to be an epigenetic mark for establishment and propagation of centromere identity. Pulse-induction of CENH3 (Drosophila CID) in Schneider S2 cells incorporates into noncentromeric regions and generates CID islands that resist clearing from chromosome arms for multiple cell generations. We demonstrate that CID islands represent functional ectopic kinetochores, which are non-randomly distributed on the chromosome and display a preferential localization near telomeres and pericentric heterochromatin in transcriptionally silent, intergenic chromatin domains. Although overexpression of heterochromatin protein 1 (HP1) or increasing Histone acetylation interferes with CID islands formation on a global scale, induction of a locally defined region of synthetic heterochromatin by targeting HP1-LacI fusions to stably integrated Lac Operator arrays produces a proximal hotspot for CID islands formation. These data suggest that the characteristics of regions bordering heterochromatin promote de novo kinetochore assembly and thereby contribute to centromere identity. ArrayExpress Release Date: 2011-07-15 Person Roles: submitter Person Last Name: Diehl Person First Name: Sarah Person Mid Initials: Person Email: diehl@immunbio.mpg.de Person Phone: (+49) 761 5108 795 Person Address: Stuebeweg 51, 79108 Freiburg im Breisgau, Germany Person Affiliation: Max-Planck-Institute for Immunobiology and Epigenetics Person Roles: investigator Person Last Name: Heun Person First Name: Patrick Person Mid Initials: Person Email: heun@immunbio.mpg.de Person Phone: (+49) 761 5108 717 Person Address: Stuebeweg 51, 79108 Freiburg im Breisgau, Germany Person Affiliation: Max-Planck-Institute for Immunobiology and Epigenetics Publication Title: Heterochromatin boundaries are hotspots for de novo kinetochore formation. Publication Author List: Agata Olszak, Dominic van Essen, Antonio J. Pereira, Sarah Diehl, Thomas Manke, Helder Maiato, Simona Saccani and Patrick Heun
Project description:This micro-array helps establishing the function of Akirin, a nuclear protein with unknown domains, a putative interacting partner, in the transcriptional regulation of the targets of Relish, a NF-kB factor required to fight Gram(-) bacteria infection in Drosophila melanogaster. S2 cells were knocked down for Relish, Akirin and immune-challenged by Calcium-phosphate transient transfection of dsRNA and over-expressing PGRP-LC vector. Positively transfected cells were sorted by co-expressed Tomato and RNA was purified and analysed by a micro-array
Project description:WARNING: This library was yield low amount of material and it was over-amplified by PCR. This libraries are used study the robustness of several statitical methods against PCR artifacts. ChIP experiments were performed on Arabidopsis wildtype inflorescences using an antibody raised against a C-terminal peptide of SEP3. ArrayExpress Release Date: 2011-04-27 Publication Title: ChIP-seq Analysis in R (CSAR): An R package for the statistical detection of protein-bound genomic regions Publication Author List: Jose M. Muino, Kerstin Kaufmann, Roeland C. H. J. van Ham, Gerco C. Angenent, and Pawel Krajewski Person Roles: submitter Person Last Name: Muino Person First Name: Jose Person Mid Initials: M. Person Email: jose.muino@wur.nl Person Phone: 0317-481122 Person Address: Droevendaalsesteeg 1, P.O. Box 16, 6700 AA Wageningen, The Netherlands Person Affiliation: Plant Research International B.V.
Project description:RNAi of signal transduction components in Drosophila S2 cells We performed RNAi knockdown experiments on 15 different signal transduction components in Drosophila S2 cells and prepared RNA libraries from the poly-adenylated fraction of the RNA. SOLiD sequencing of strand-specific, barcoded transcriptome libraries yielded expression profiles allowing us to extract common pathway signatures and indicated that Cka may function as novel regulator in Ras/MAPK signaling. ArrayExpress Release Date: 2011-07-08 Person Roles: investigator Person Last Name: Boutros Person First Name: Michael Person Email: m.boutros@dkfz.de Person Address: Deutsches Krebsforschungszentrum, Signaling and Functional Genomics (B110), Im Neuenheimer Feld 580, 69120 Heidelberg, Germany Person Affiliation: Signaling and Functional Genomics, DKFZ Person Roles: investigator Person Last Name: Sandmann Person First Name: Thomas Person Email: t.sandmann@dkfz.de Person Address: Deutsches Krebsforschungszentrum, Signaling and Functional Genomics (B110), Im Neuenheimer Feld 580, 69120 Heidelberg, Germany Person Affiliation: Signaling and Functional Genomics, DKFZ Person Roles: investigator Person Last Name: Horn Person First Name: Thomas Person Email: t.horn@dkfz.de Person Address: Deutsches Krebsforschungszentrum, Signaling and Functional Genomics (B110), Im Neuenheimer Feld 580, 69120 Heidelberg, Germany Person Affiliation: Signaling and Functional Genomics, DKFZ Person Roles: submitter Person Last Name: Kerr Person First Name: Grainne Person Email: g.kerr@dkfz.de Person Address: Deutsches Krebsforschungszentrum, Signaling and Functional Genomics (B110), Im Neuenheimer Feld 580, 69120 Heidelberg, Germany Person Affiliation: Signaling and Functional Genomics, DKFZ
Project description:ChiP-seq profiling of Drosophila melanogaster salivary glands to identify targets for NSL1 and MCRS2. ArrayExpress Release Date: 2010-04-16 Publication Title: The Nonspecific Lethal Complex Is a Transcriptional Regulator in Drosophila Publication Author List: Raja SJ, Charapitsa I, Conrad T, Vaquerizas JM, Gebhardt P, Holz H, Kadlec J, Fraterman S, Luscombe NM, Akhtar A. Person Roles: submitter Person Last Name: Vaquerizas Person First Name: Juan Person Mid Initials: M Person Email: jvaquerizas@ebi.ac.uk Person Phone: Person Address: Person Affiliation: EBI
Project description:Genome scale metabolic model of Drosophila gut microbe Acetobacter fabarum
Abstract -
An important goal for many nutrition-based microbiome studies is to identify the metabolic function of microbes in complex microbial communities and their impact on host physiology. This research can be confounded by poorly understood effects of community composition and host diet on the metabolic traits of individual taxa. Here, we investigated these multiway interactions by constructing and analyzing metabolic models comprising every combination of five bacterial members of the Drosophila gut microbiome (from single taxa to the five-member community of Acetobacter and Lactobacillus species) under three nutrient regimes. We show that the metabolic function of Drosophila gut bacteria is dynamic, influenced by community composition, and responsive to dietary modulation. Furthermore, we show that ecological interactions such as competition and mutualism identified from the growth patterns of gut bacteria are underlain by a diversity of metabolic interactions, and show that the bacteria tend to compete for amino acids and B vitamins more frequently than for carbon sources. Our results reveal that, in addition to fermentation products such as acetate, intermediates of the tricarboxylic acid (TCA) cycle, including 2-oxoglutarate and succinate, are produced at high flux and cross-fed between bacterial taxa, suggesting important roles for TCA cycle intermediates in modulating Drosophila gut microbe interactions and the potential to influence host traits. These metabolic models provide specific predictions of the patterns of ecological and metabolic interactions among gut bacteria under different nutrient regimes, with potentially important consequences for overall community metabolic function and nutritional interactions with the host.IMPORTANCE Drosophila is an important model for microbiome research partly because of the low complexity of its mostly culturable gut microbiota. Our current understanding of how Drosophila interacts with its gut microbes and how these interactions influence host traits derives almost entirely from empirical studies that focus on individual microbial taxa or classes of metabolites. These studies have failed to capture fully the complexity of metabolic interactions that occur between host and microbe. To overcome this limitation, we reconstructed and analyzed 31 metabolic models for every combination of the five principal bacterial taxa in the gut microbiome of Drosophila This revealed that metabolic interactions between Drosophila gut bacterial taxa are highly dynamic and influenced by cooccurring bacteria and nutrient availability. Our results generate testable hypotheses about among-microbe ecological interactions in the Drosophila gut and the diversity of metabolites available to influence host traits.
Project description:Neurons are highly polarized cells with distinct protein compositions in axonal and dendritic compartments. Cellular mechanisms controlling polarized protein sorting have been described for mature nervous system but little is known about the segregation in newly differentiated neurons. In a forward genetic screen for regulators of Drosophila brain circuit development, we identified mutations in <span style="color: rgb(54, 54, 54); font-style: normal; font-weight: 400; background-color: rgb(245, 245, 245);">Serine Palmitoyltransferase </span>(SPT), an evolutionary conserved enzyme in sphingolipid biosynthesis. Here we show that reduced levels of sphingolipids in SPT mutants cause axonal morphology defects similar to loss of cell recognition molecule Dscam. Loss- and gain-of-function studies show that neuronal sphingolipids are critical to prevent aggregation of axonal and dendritic Dscam isoforms, thereby ensuring precise Dscam localization to support axon branch segregation. Furthermore, SPT mutations causing neurodegenerative HSAN-I disorder in humans also result in formation of stable Dscam aggregates and axonal branch phenotypes in Drosophila neurons, indicating a causal link between developmental protein sorting defects and neuronal dysfunction.