Identification of genes dependent on the Ecdysone receptor (EcR) at the onset of metamorphosis in Drosophila
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ABSTRACT:
ORGANISM(S): Drosophila melanogaster
PROVIDER: GSE3069 | GEO | 2005/10/04
SECONDARY ACCESSION(S): PRJNA93165
REPOSITORIES: GEO
Similar Datasets
Project description:This study identifies those genes that are dependent on EcR for their proper regulation at the onset of metamorphosis in Drosophila melanogaster. Experiment Overall Design: hs-EcRi-11 third instar larvae were heat-treated twice at 37°C, each time for 1 hour, at 24 hours and 18 hours prior to pupariation, as described [29]. RNA was harvested for microarray analysis at -4, 0, and 4 hours relative to pupariation from three independent collections of animals for each time point. Data obtained from these arrays was compared to array data from control animals at the same stages of development to identify EcR-dependent genes.
2007-11-11 | E-GEOD-3069 | biostudies-arrayexpress
Project description:This study identifies genes that show EcR-dependent gene expression in MB neurons at the onset of axon pruning. Keywords: nuclear receptor gene regulation
2008-06-01 | GSE10013 | GEO
Project description:Coupling immunity and development is essential to ensure survival despite changing internal conditions in the organism. The metamorphosis of the fruit fly represents a striking example of drastic and systemic physiological changes that need to be integrated with the innate immune system. However, the mechanisms that coordinate development and immune cell activity in the transition from larva to adult in Drosophila remain to elucidate. The steroid hormone ecdysone is known to act as a key coordinator of metamorphosis. This hormone activates a nuclear receptor, the Ecdysone Receptor (EcR), which acts as a heterodimer with its partner Ultraspiracle (USP). Together, they activate the transcription of primary response genes, which in turn activate the transcription of a battery of late response genes. We have revealed that regulation of macrophage-like cells (hemocytes) by the steroid hormone ecdysone is essential for an effective innate immune response over metamorphosis. We have shown that in response to ecdysone signalling, hemocytes rapidly up regulate actin dynamics, motility and phagocytosis of apoptotic corpses, and acquire the ability to chemotax to damaged epithelia. Most importantly, individuals lacking ecdysone-activated hemocytes are defective in bacterial phagocytosis and are fatally susceptible to infection by bacteria ingested at larval stages, despite the normal systemic production of antimicrobial peptides. This decrease in survival is comparable to the one observed in pupae lacking immune cells altogether, indicating that ecdysone-regulation is essential to hemocyte immune functions and survival after infection. To better understand the ecdysone regulation of hemocyte activities, we have performed gene expression analysis. In order to identify the genes which expression change at the onset of metamorphosis, we have sorted hemocytes from 3rd instar larvae and from young prepupae and compared their gene expression. Moreover, and in order to identify which genes are regulated by the ecdysone signalling, we have used individuals expressing a dominant negative form of the Ecdysone Receptor specifically in their hemocytes. We have sorted hemocytes from 3rd instar and young prepupae of this genotype to compare their gene expression to the gene expression in larvae and prepupae from the control individuals. Hemocytes were isolated by FACS from selected 3rd instar larvae (at the late feeding stage) and prepupae (from 1h to 2h after puparium formation - APF) corresponding to two different genotypes: individuals w;HmlDeltaGal4, UAS-GFP/+ that express GFP specifically in hemocytes (genotype control), and individuals w;HmlDeltaGal4; UAS-GFP/UAS-EcRB1DN W650A which hemocytes express an Ecdysone Receptor Dominant Negative construct in addition to the GFP (EcRDN). For each of the four conditions we performed three biological replicates.
2013-10-25 | E-GEOD-49326 | biostudies-arrayexpress
Project description:Coupling immunity and development is essential to ensure survival despite changing internal conditions in the organism. The metamorphosis of the fruit fly represents a striking example of drastic and systemic physiological changes that need to be integrated with the innate immune system. However, the mechanisms that coordinate development and immune cell activity in the transition from larva to adult in Drosophila remain to elucidate. The steroid hormone ecdysone is known to act as a key coordinator of metamorphosis. This hormone activates a nuclear receptor, the Ecdysone Receptor (EcR), which acts as a heterodimer with its partner Ultraspiracle (USP). Together, they activate the transcription of primary response genes, which in turn activate the transcription of a battery of late response genes. We have revealed that regulation of macrophage-like cells (hemocytes) by the steroid hormone ecdysone is essential for an effective innate immune response over metamorphosis. We have shown that in response to ecdysone signalling, hemocytes rapidly up regulate actin dynamics, motility and phagocytosis of apoptotic corpses, and acquire the ability to chemotax to damaged epithelia. Most importantly, individuals lacking ecdysone-activated hemocytes are defective in bacterial phagocytosis and are fatally susceptible to infection by bacteria ingested at larval stages, despite the normal systemic production of antimicrobial peptides. This decrease in survival is comparable to the one observed in pupae lacking immune cells altogether, indicating that ecdysone-regulation is essential to hemocyte immune functions and survival after infection. To better understand the ecdysone regulation of hemocyte activities, we have performed gene expression analysis. In order to identify the genes which expression change at the onset of metamorphosis, we have sorted hemocytes from 3rd instar larvae and from young prepupae and compared their gene expression. Moreover, and in order to identify which genes are regulated by the ecdysone signalling, we have used individuals expressing a dominant negative form of the Ecdysone Receptor specifically in their hemocytes. We have sorted hemocytes from 3rd instar and young prepupae of this genotype to compare their gene expression to the gene expression in larvae and prepupae from the control individuals.
2013-10-25 | GSE49326 | GEO
Project description:Ecdysone signaling has long been studied as a paradigm for how hormones can synchronize development events in tissues throughout the animal. At the genetic level, ecdysone acts through its receptor, EcR, which has been classically thought to act at a relatively small number of canonical, ecdysone-responsive genes which then go on to activate the effectors of cellular processes. However, in spite of the decades of work studying EcR, the understanding of how EcR promotes changes in gene expression genome-wide in vivo remains incomplete. To examine EcR’s role in promoting changes in gene expression, we use a tissue-specific GAL4 driver to knockdown EcR throughout wing development and perform RNAseq on both WT wings and EcR-RNAi wings at -6h after puparium formation (APF) and +6hAPF. We find that EcR is required to promote thousands of gene expression changes genome-wide. To determine whether EcR is directly effecting these changes, we perform CUT&RUN in wings to identify EcR binding sites genome-wide. We find that EcR directly binds thousands of sites genome-wide, including many genes important for wing development. Collectively, these data suggest that EcR does not only act the top of a signaling cascade, but, instead, directly effects the response to ecdysone at multiple levels.
2019-04-24 | GSE124254 | GEO
Project description:In Drosophila, the ecdysone steroid hormone is essential for coordinating developmental timing across physically separated tissues. Ecdysone directly impacts genome function through its receptor, a heterodimer of the EcR and Usp proteins. Ligand binding to EcR triggers a transcriptional cascade, including activation of a set of primary response transcription factors. The hierarchical organization of this pathway has left the direct role of EcR in mediating ecdysone responses obscured. Here, we investigate the role of EcR in controlling tissue-specific ecdysone responses, focusing on two tissues that diverge in their response to rising ecdysone titers: the larval salivary gland, which undergoes programmed destruction, and the wing imaginal disc, which initiates metamorphosis. We find that EcR functions bimodally, with both gene repressive and activating functions, even at the same developmental stage. We find that EcR DNA binding profiles are highly tissue-specific, and transgenic reporter analyses demonstrate that EcR plays a direct role in controlling enhancer activity. Despite a strong correlation between tissue-specific EcR binding and tissue-specific open chromatin, we find that EcR does not control chromatin accessibility at genomic targets. We conclude that EcR contributes extensively to tissue-specific ecdysone responses. However, control over access to its binding sites is subordinated to other transcription factors.
2022-09-12 | GSE202809 | GEO
Project description:In Drosophila, the ecdysone steroid hormone is essential for coordinating developmental timing across physically separated tissues. Ecdysone directly impacts genome function through its receptor, a heterodimer of the EcR and Usp proteins. Ligand binding to EcR triggers a transcriptional cascade, including activation of a set of primary response transcription factors. The hierarchical organization of this pathway has left the direct role of EcR in mediating ecdysone responses obscured. Here, we investigate the role of EcR in controlling tissue-specific ecdysone responses, focusing on two tissues that diverge in their response to rising ecdysone titers: the larval salivary gland, which undergoes programmed destruction, and the wing imaginal disc, which initiates metamorphosis. We find that EcR functions bimodally, with both gene repressive and activating functions, even at the same developmental stage. We find that EcR DNA binding profiles are highly tissue-specific, and transgenic reporter analyses demonstrate that EcR plays a direct role in controlling enhancer activity. Despite a strong correlation between tissue-specific EcR binding and tissue-specific open chromatin, we find that EcR does not control chromatin accessibility at genomic targets. We conclude that EcR contributes extensively to tissue-specific ecdysone responses. However, control over access to its binding sites is subordinated to other transcription factors.
2022-09-12 | GSE202808 | GEO
Project description:In Drosophila, the ecdysone steroid hormone is essential for coordinating developmental timing across physically separated tissues. Ecdysone directly impacts genome function through its receptor, a heterodimer of the EcR and Usp proteins. Ligand binding to EcR triggers a transcriptional cascade, including activation of a set of primary response transcription factors. The hierarchical organization of this pathway has left the direct role of EcR in mediating ecdysone responses obscured. Here, we investigate the role of EcR in controlling tissue-specific ecdysone responses, focusing on two tissues that diverge in their response to rising ecdysone titers: the larval salivary gland, which undergoes programmed destruction, and the wing imaginal disc, which initiates metamorphosis. We find that EcR functions bimodally, with both gene repressive and activating functions, even at the same developmental stage. We find that EcR DNA binding profiles are highly tissue-specific, and transgenic reporter analyses demonstrate that EcR plays a direct role in controlling enhancer activity. Despite a strong correlation between tissue-specific EcR binding and tissue-specific open chromatin, we find that EcR does not control chromatin accessibility at genomic targets. We conclude that EcR contributes extensively to tissue-specific ecdysone responses. However, control over access to its binding sites is subordinated to other transcription factors.
2022-09-12 | GSE202807 | GEO
Project description:MicroRNAs (miRNAs) are endogenous RNA molecules that contribute to the regulation of gene expression post-transcriptionally. Recently, patterns of sequence evolution and evolutionary emergence of miRNAs have been analyzed in detail. However, the extent to which miRNA expression levels vary within and between species, the role of stabilizing selection versus other evolutionary mechanisms in shaping the temporal dynamics of these changes, and how this variation might unveil the interplay between miRNAs and mRNAs remain poorly understood. This is especially true during key developmental transitions involving miRNA regulation. Combining deep-sequencing with multi-species microarrays, we assayed miRNA expression levels immediately before (≥18BPF) and after (PF) the increase in steroid hormone ecdysone that triggers metamorphosis. We did so both at the intra- and interspecific levels in the Drosophila melanogaster species group. In contrast to their sequence conservation, ~25% of the analyzed miRNAs differed significantly in expression levels at ≥18BPF and/or PF across D. melanogaster strains. Additionally, ~33% showed modifications in their pattern of expression bias between developmental timepoints. Relative to the patterns of evolution, changes in miRNA abundance at PF accumulate linearly over evolutionary time while similar changes at ≥18BPF do not. Importantly, expression levels of ≥18BPF-enriched miRNAs are the most variable within and between species and therefore the least likely to evolve under stabilizing selection, especially as compared to non-developmentally enriched miRNAs. Overall, functional attributes such as expression ubiquity are more tightly associated with lower levels of miRNA expression polymorphism at PF than at ≥18BPF. Furthermore, ≥18BPF- and PF-enriched miRNAs showed opposite patterns of covariation in expression with mRNAs, which was found to denote the type of regulatory relationship between miRNA and mRNA. By focusing on the miRNA expression levels at the onset of metamorphosis, our results have unveiled contrasting functional patterns of evolutionary divergence during ontogeny.
2014-08-06 | GSE57438 | GEO
Project description:In Drosophila, male-specific FRU (FRUM) is required to establish the potential for courtship behaviors, but the downstream effectors of FRUM during development are largely unknown. A microarray-based approach identified genes that are differentially expressed as a consequence of FRUM in pupae, in both whole body and CNS tissues. Genes were also identified that are sex-differentially expressed in CNS tissues. The FRUM-regulated sets were significantly overrepresented with genes also regulated by the ecdysone regulatory pathway. Two EcR isoforms (EcRA and EcRB1) are expressed in FRUM-expressing neurons during distinct periods of metamorphosis. Males with abrogated EcRA function in FRUM-expressing neurons aggressively court other males. Transcriptional profiles of mutants with abrogated EcRA function in the fru circuit demonstrate that EcR and FRUM regulate common gene sets, including the early gene broad. These results demonstrate a novel role for EcR in specifying male courtship behavior through its actions specifically in the FRUM neural circuitry.
2009-09-21 | GSE11752 | GEO