Drosophila melanogaster
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA283208 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:The Notch pathway is a well conserved cell to cell communication mechanism that is normally involved in many developmental processes and when aberrantly activated it leads to diseases such as cancer. One such example is the neural stem cell tumours that arise from constitutive Notch activity in Drosophila neuroblasts from the larval Central Nervous System (CNS). To investigate how hyper-activation of Notch in larval neuroblasts leads to tumours, we mapped genome-widely the regions that are bound by Su(H) (the core Notch pathway transcription factor, known as CSL in mammals). We combined these results with the profiling of upregulated mRNAs in CNSs where Notch is hyper-activated for 24h vs control CNSs and identified 127 putative direct Notch targets in the hyperplastic CNSs. Included were genes associated with the neuroblast maintenance and self-renewal programme and genes coding for temporal transcription factors, which are involved in neuroblast progression and generation of progeny with specific identity over time. Thus, Notch induces neural stem cell tumors by promoting the expression of genes that contribute to stem cell identity and by reprogramming expression of temporal factors that regulate maturity. Su(H) binding profile in Drosophila larval CNSs where Notch is constitutively active for 24 hours. In total there are 3 samples of Su(H) ChIP in Notch hyper-activated larval CNSs.
2015-12-15 | E-GEOD-68614 | biostudies-arrayexpress
Project description:The Notch pathway is a well conserved cell to cell communication mechanism that is normally involved in many developmental processes and when aberrantly activated it leads to diseases such as cancer. One such example is the neural stem cell tumours that arise from constitutive Notch activity in Drosophila neuroblasts from the larval Central Nervous System (CNS). To investigate how hyper-activation of Notch in larval neuroblasts leads to tumours, we mapped genome-widely the regions that are bound by Su(H) (the core Notch pathway transcription factor, known as CSL in mammals). We combined these results with the profiling of upregulated mRNAs in CNSs where Notch is hyper-activated for 24h vs control CNSs and identified 127 putative direct Notch targets in the hyperplastic CNSs. Included were genes associated with the neuroblast maintenance and self-renewal programme and genes coding for temporal transcription factors, which are involved in neuroblast progression and generation of progeny with specific identity over time. Thus, Notch induces neural stem cell tumors by promoting the expression of genes that contribute to stem cell identity and by reprogramming expression of temporal factors that regulate maturity.
2015-12-15 | GSE68614 | GEO
Project description:Aim: Su(H) chromatin occupancy profiling by ChIP on larval wing imaginal discs of Drosophila melanogaster to study the cooperation between Notch activation and loss of epithelial polarity (scrib mutation) during neoplastic growth. Results: The combination of Notch activation and scribble mutation (NS) does not lead to a general redeployment of Su(H) binding as compared to individual conditions (Notch only (N), and scrib mutation only (S))
2021-10-08 | GSE185490 | GEO
Project description:The conserved Notch pathway functions in diverse developmental and disease-related processes, requiring mechanisms to ensure appropriate target-selection and gene activation in each context. To investigate, we partitioned Drosophila chromatin into different states, based on histone modifications, establishing the preferred chromatin conditions for binding of CSL, the Notch pathway transcription factor. While most histone modifications were unchanged by CSL binding or Notch activation, rapid changes in H3K56 acetylation occurred at Notch regulated-enhancers. This modification extended over large regions, required the histone acetyl-transferase CBP and was independent of transcription. Such rapid changes in H3K56 acetylation are a conserved indicator of enhancer activation, also occurring at mammalian Notch-regulated Hey1 and at Drosophila ecdysone-regulated genes. This core histone modification may therefore underpin the changes in chromatin accessibility needed to promote transcription following signaling activation. Su(H) profile of BG3 cells in control condition and EGTA treated condition. In total 8 samples, 4 replicates of Su(H) ChIP in hbss condition and 4 replicates of Su(H) ChIP in EGTA treated BG3 cells.
2015-07-01 | E-GEOD-66225 | biostudies-arrayexpress
Project description:The conserved Notch pathway functions in diverse developmental and disease-related processes, requiring mechanisms to ensure appropriate target-selection and gene activation in each context. To investigate, we partitioned Drosophila chromatin into different states, based on histone modifications, establishing the preferred chromatin conditions for binding of CSL, the Notch pathway transcription factor. While most histone modifications were unchanged by CSL binding or Notch activation, rapid changes in H3K56 acetylation occurred at Notch regulated-enhancers. This modification extended over large regions, required the histone acetyl-transferase CBP and was independent of transcription. Such rapid changes in H3K56 acetylation are a conserved indicator of enhancer activation, also occurring at mammalian Notch-regulated Hey1 and at Drosophila ecdysone-regulated genes. This core histone modification may therefore underpin the changes in chromatin accessibility needed to promote transcription following signaling activation. Su(H) profile of Kc cells transfected with GFP-Su(H). In total 6 samples, 3 replicates of anti-GFP ChIP and corresponding total input samples in Kc cells.
2015-07-01 | E-GEOD-66226 | biostudies-arrayexpress
Project description:Notch signaling is an evolutionarily conserved signal transduction pathway that is essential for metazoan development. At the molecular level, the key components of the Notch pathway are the NOTCH-family receptors, the ligands of the DSL (Delta, Serrate, Lag-2) family and the transcription factor CSL [CBF1/RBPJ, Su(H), Lag-1]. Upon ligand binding, the NOTCH Intra-Cellular Domain (NOTCH ICD) translocates into the nucleus and forms a complex with RBPJ to activate the transcription of target genes. In the absence of NOTCH ICD, RBPJ acts as a transcriptional repressor. Using a proteomic approach, we identified L3MBTL3 as a novel interactor of RBPJ. We discovered that L3MBTL3 competes with NOTCH ICD for binding to RBPJ. In the absence of NOTCH ICD, RBPJ recruits L3MBTL3 and its co-factor KDM1A [lysine (K)-specific demethylase 1A] to the promoters/enhancers of Notch target genes to promote H3K4me2 demethylation and transcriptional repression. In three distinct cell contexts in which Notch signaling governs cell fate, i.e., mature T-cells as well as brain and breast tumor cells, the loss of L3MBTL3 results in the de-repression of Notch target genes. Finally, the genetic analyses of the homologs of RBPJ and L3MBTL3 in Drosophila melanogaster and Caenorhabditis elegans demonstrate that the functional link between RBPJ/Su(H)/lag-1 and L3MBTL3/dL(3)mbt/lin-61 is evolutionarily conserved, thus identifying L3MBTL3 as a universal modulator of Notch signaling in metazoans.
2017-10-17 | PXD004196 | Pride
Project description:Aim: mRNA profile of larval wing imaginal discs of Drosophila melanogaster to study the cooperation between Notch activation and loss of epithelial polarity (scrib mutation) during neoplastic growth. Results: The combination of Notch activation and scribble mutation (NS) results in mRNA expression changes that, while partly overlapping with Notch only (N), and with scrib mutation only (S), are unique to the combination
2021-10-07 | GSE185339 | GEO
Project description:Notch signalling is involved in a multitude of developmental decisions and its aberrant activation is linked to many diseases, including cancers. One such example is the neural stem cell tumours that arise from constitutive Notch activity in Drosophila neuroblasts. To investigate how hyper-activation of Notch in larval neuroblasts leads to tumours, we combined results from profiling the upregulated mRNAs and mapping the regions bound by Su(H) (the core Notch pathway transcription factor ). This identified 127 putative direct Notch targets that were up-regulated in the hyperplastic tissue. These genes were highly enriched for transcription factors (TFs) and overlapped significantly with a previously identified regulatory programme dependent on the proneural transcription factor Asense. Included were genes associated with the neuroblast maintenance and self-renewal programme that we validated as Notch regulated in vivo. A second category contained so-called temporal transcription factors, which are involved in neuroblast progression. Normally expressed in specific time windows, several temporal transcription factors were ectopically expressed in the stem cell tumours, suggesting that Notch had reprogrammed the normal temporal hierarchy. Indeed, the Notch-induced hyperplasia was reduced by mutations affecting two of the temporal factors which, conversely, were sufficient to induce mild hyperplasia on their own. Altogether the results demonstrate that Notch induces neural stem cell tumors by promoting the expression of genes that contribute to stem cell identity and by reprogramming expression of temporal factors that regulate maturity.
2016-10-18 | E-MTAB-3561 | biostudies-arrayexpress
Project description:Drosophila neuroblasts have emerged as a model for stem cell biology that is ideal for genetic analysis but is limited by the lack of cell-type specific gene expression data. Here, we describe a methodology to isolate large numbers of pure neuroblasts and differentiating neurons that retain both cell cycle and lineage characteristics. We determine transcriptional profiles by mRNA sequencing and identify 28 predicted neuroblast specific transcription factors, which can be arranged in a network containing hubs for Notch signaling, growth control and chromatin regulation. Overexpression and RNAi for these factors identify Klumpfuss as a regulator of self-renewal. We show that loss of Klu function causes premature differentiation while overexpression results in the formation of transplantable brain tumors. Our data represent a valuable resource for Drosophila developmental neurobiology and we describes methodology that can be applied to other invertebrate stem cell lineages as well. comparison of transcriptomes of Drosophila melanogaster larval neuroblasts and their differentiated daughter cells (neurons)
2012-08-21 | E-GEOD-38764 | biostudies-arrayexpress
Project description:Several co-repressors interact directly with the DNA-binding protein CSL [Su(H) in Drosophila] and are proposed to keep target genes silenced in the absence of Notch activity. To investigate co-repressor activity in the context of this well defined signalling pathway, we analysed the genome-wide binding profile of the best-characterized CSL co-repressor in Drosophila, Hairless, in Kc cells and in wing imaginal discs. The binding profile in wing discs of a second CSL interacting repressor, SMRTER, was also analysed. There was significant overlap between Hairless and Su(H), both in Kc cells and in wing discs, where they were predominantly found in chromatin with active enhancer marks. The Hairless complex was widely present at some Notch regulated enhancers in the wing disc,but no binding was detected at others, indicating that it is not essential for silencing per se. Analysis of target enhancers confirmed differential requirements for Hairless. SMRTER binding significantly overlapped with Hairless, rather than complementing it, and many enhancers were apparently co-bound by both factors. Our analysis indicates that the actions of Hairless and SMRTER gate the enhancers to Notch activity and to Ecdysone signalling respectively, to ensure that the appropriate levels and timing of target gene expression are achieved.
2017-12-31 | GSE97599 | GEO