Project description:PSC overexpression can cause phenotypes specifically in an rbf1 mutant background, likely due to a sensitization to PSC-induced phenotypes. The goal of this study is to understand the interaction between rbf1 hypomorphic mutation and the overexpression of Polycomb group gene Posterior sex combs. We used Drosophila larval eye imaginal discs that were mutant for rbf1 or overexpressing PSC and compared these to control larval eye discs to assess changes in gene expression. We identified a common set of genes that are deregulated when rbf1 is mutated or when PSC is overexpressed. RNA was extracted from eye imaginal discs dissected from third instar Drosophila larvae. Samples were amplified and hybridized to Affymetrix Drosophila Genome 2.0 Array. To better understand the effects of rbf1 mutation and PSC overexpression, we compared the gene expression of rbf1 mutant eye discs and eye discs overexpressing PSC to control eye discs.
Project description:In this study we use Tag-sequencing in eye-antennal and wing imaginal discs across Drosophila species to determine a set of conserved eye-specific developmental genes. Next, we perform motif discovery analysis using the tool i-cisTarget, to depict the core gene developmental network underlying compound eye photoreceptor. The Glass position weight matrix appears as the most highly overrepresented motif, thus positioning Glass as a master regulator in compound eye photoreceptor development. Differential gene expression analysis by RNA-seq in D.melanogaster wild-type eye-antennal versus glass mutant [gl 60j] shows that the majority of our predicted Glass targets show strong downregulation in the glass mutant. This SuperSeries is composed of the following subset Series: GSE39781: RNA-seq in wild-type and glass mutant eye-antennal discs in Drosophila melanogaster GSE39782: Tag-seq profiling in eye-antennal and wing imaginal discs of D. melanogaster, D. yakuba and D. virilis
Project description:To probe mechanistic determinants of Yki function in mitochondrial biogenesis, we conducted a genome-wide microarray experiment, and specifically compared expression patterns of genes from control (GMR gal4) and Yorkie over-expressing (GMR gal4; UAS yki) pupal eye discs. The above mentioned genotypes were grown at 29 deg C and at about 40 hrs after pupariation, the pupal eye discs were dissected. RNA was extracted from the pupal eye discs, purified and used to generate microarray probes that were hybridized to the Drosophila genome 2 arrays (Affymetrix). The Gene Chip Operating system (Affymetrix) and dCHIP program (Harvard University) were used to generate pairwise comparisons between the transcription profiles of control and Yorkie over-expressing discs.
Project description:We have used microarrays to identify genes expressed and required for the second mitotic wave (SMW) during eye development. Eye discs expressing Spitz under the control of GMR Gal4 have no SMW as Spitz promotes G1 arrest, ectopic differentiation also occures. To control for the ectopic differentiation, Spi expressing eye antennal discs were compared to eye antennal discs expressing activated RasV12. In discs expresseding RasV12 under the control of GMRGal4 the SMW takes place normally prior to any ectopic differentiation. We used microarrays to detail the global programme of gene expression underlying cellularisation and identified distinct classes of up-regulated genes during this process. Experiment Overall Design: Drosophila eye antennal imaginal discs expressing either UAS RasV12 or UAS Spi under the control of GMRGal4 were dissected from 3rd instar larvae for RNA extraction and hybridization on Affymetrix microarrays.
Project description:Apoptosis is an important process to eliminate cells from tissue which have incurred irreparable DNA damage. While dE2F1/dDP complexes respond to such damage by transcriptionally activating apoptotic genes, previous data suggests that activation of the previously characterized apoptotic target genes of dE2F1/dDP alone may not be the only gene regulation important for gamma irradiation-induced apoptosis. Here we report that following irradiation in dDP mutant 3rd instar larval eye imaginal discs, many genes important for oxidative phosphorylation are down-regulated, which are not down-regulated following irradiation in wild type eye discs. Biological triplicates of wild type, dDP mutant and de2f1, deleted in the posterior, eye discs were untreated or irradiated with 40Gy of gamma radiation. Total RNA was extracted by Trizol from untreated eye discs and from irradiated eye discs 4h after irradiation. RNA was column purified. PCR amplified RNAs were hybridized on Affymetrix Drosophila Genome 2.0 Array.
Project description:Genomic enhancers regulate spatio-temporal gene expression by recruiting specific combinations of transcription factors (TFs). When TFs are bound to active regulatory regions, they displace canonical nucleosomes, making these regions biochemically detectable as nucleosome-depleted regions or accessible/open chromatin. Here we ask whether open chromatin profiling can be used to identify the entire repertoire of active promoters and enhancers underlying tissue-specific gene expression during normal development and oncogenesis in vivo. To this end, we first compare two different approaches to detect open chromatin in vivo using the Drosophila eye primordium as a model system: FAIRE-seq, based on physical separation of open versus closed chromatin; and ATAC-seq, based on preferential integration of a transposon into open chromatin. We find that both methods reproducibly capture the tissue-specific chromatin activity of regulatory regions, including promoters, enhancers, and insulators. Using both techniques, we screened for regulatory regions that become ectopically active during Ras-dependent oncogenesis, and identified 3778 regions that become (over-)activated during tumor development. Next, we applied motif discovery to search for candidate transcription factors that could bind these regions and identified AP-1 and Stat92E as key regulators. We validated the importance of Stat92E in the development of the tumors by introducing a loss of function Stat92E mutant, which was sufficient to rescue the tumor phenotype. Additionally we tested if the predicted Stat92E responsive regulatory regions are genuine, using ectopic induction of JAK/STAT signaling in developing eye discs, and observed that similar chromatin changes indeed occurred. Finally, we determine that these are functionally significant regulatory changes, as nearby target genes are up- or down-regulated. In conclusion, we show that FAIRE-seq and ATAC-seq based open chromatin profiling, combined with motif discovery, is a straightforward approach to identify functional genomic regulatory regions, master regulators, and gene regulatory networks controlling complex in vivo processes. FAIRE-Seq in Drosophila wild type eye-antennal imaginal discs (2 wt strains); ATAC-Seq in Drosophila wild type eye-antennal imaginal discs (3 wt strains) ; FAIRE-Seq in Drosophila Ras/Scrib induced eye disc tumors (1 early and 1 late); ATAC-Seq in Drosophila Ras/Scrib induced eye disc tumors (1 early and 1 late); ATAC-Seq in Drosophila eye discs with Unpaired over-expression (2 biological replicates); CTCF ChIP-seq in Drosophila eye discs; ChIP-seq input in Drosophila eye discs
Project description:Atonal is a proneural transcription factor expressed in the Drosophila eye imaginal discs. To characterize the putative targes of Atonal in the eye discs we have used an endogenously GFP-tagged version of atonal to immunoprecipate disc samples with anti-GFP antibodies
Project description:We have used microarrays to identify genes expressed and required for the second mitotic wave (SMW) during eye development. Eye discs expressing Spitz under the control of GMR Gal4 have no SMW as Spitz promotes G1 arrest, ectopic differentiation also occures. To control for the ectopic differentiation, Spi expressing eye antennal discs were compared to eye antennal discs expressing activated RasV12. In discs expresseding RasV12 under the control of GMRGal4 the SMW takes place normally prior to any ectopic differentiation. We used microarrays to detail the global programme of gene expression underlying cellularisation and identified distinct classes of up-regulated genes during this process. Keywords: Comparison of eye antennal discs of two different over expression genotypes
Project description:The goal of this study was to examine RNA expression levels in the Drosophila larval eye and antennal discs and determine whether higher levels of transcription were correlated with the ability of transgenes to drive pairing with their homologous endogenous loci between chromosomes. Additionally, RNA expression levels were compared between the eye and antennal discs to determine whether increased insulator protein expression contributed to increased pairing in the eye disc.
Project description:Although the JAK/STAT pathway regulates numerous processes in vertebrates and invertebrates through modulating transcription, its functionally-relevant transcriptional targets remain largely unknown. With one jak and one stat (stat92E), Drosophila provides a powerful system for finding new JAK/STAT target genes. Genome-wide expression profiling on eye discs in which Stat92E is hyperactivated, revealed 584 differentially-regulated genes, including known targets domeless, socs36E and wingless. Other differentially-regulated genes (chinmo, lama, Mo25, Imp-L2, Serrate, Delta) were validated and may represent new Stat92E targets. Genetic experiments revealed that Stat92E cell-autonomously represses Serrate, which encodes a Notch ligand. Loss of Stat92E led to de-repression of Serrate in the dorsal eye, resulting in ectopic Notch signaling and aberrant eye growth there. Thus, our micro-array documents a new Stat92E target gene and a previously-unidentified inhibitory action of Stat92E on Notch signaling. These data suggest that this study will be a useful resource for the identification of additional Stat92E targets. Identification of the JAK/STAT pathway target genes in the Drosophila eye disc Keywords: Genotype comparison Gene expression profiles from five biological replicates of eye discs with yw (control) and GMR-upd (overexpressing JAK/STAT ligand unpaired) were compared using genome wide mRNA expression profiling by Affymetrix genechip arrays (Drosophila 2.0) and key targets were validated by clonal analysis, in situ hybridization, immunohistochemical staining and quantitative real-time PCR.