Project description:Profiling of changes in steady state RNA levels upon RNAi-mediated knockdown of the chromosomal kinase JIL-1 in Drosophila S2 cells.
Project description:Profiling of changes in steady state RNA levels upon RNAi-mediated knockdown of the chromosomal kinase JIL-1 in Drosophila S2 cells. Drosophila S2 cells were incubated 7 days after treatment with 10 µg of dsRNA directed against GST/EGFP or JIL-1, respectively. 5 biological replicates per target have been collected.
Project description:In this work, we use RNAi and subsequent RNA isolation and Affymetrix Expression array analysis to map the genome-wide transcriptional targets of 107 of the strongest cell cycle regulators. Drosophila S2 cells were used with RNAi target gene knockdown compared to control (GFP dsRNA). RMA normalized data re-annotated using a custom CDF is available on the FTP site for this experiment. E-MTAB-1648, E-MTAB-1364 and E-MTAB-453 are all data from: Bonke M, et al. (2013) Transcriptional networks controlling the cell cycle. G3 (Bethesda) 3, 75-90, PMID: 23316440.
Project description:The Drosophila phagocytic receptor Eater is expressed specifically in phagocytic hemocytes. It contributes to host immune defense and is required for survival of bacterial infections. Eater is involved in recognition and phagocytosis of bacteria. We used microarrays to determine whether any gene expression changes after bacterial phagocytosis are dependent on the expression of the phagocytic scavenger receptor Eater. We found transcriptional regulation in response to bacterial internalization, but no significant differences between controls and samples in which eater expression had been diminshed by RNAi eater knock down. Drosophila S2 cells, a hemocyte-derived cell line with phagocytic properties, were exposed to a mixture of Gram-positive and Gram-negative bacteria at conditions of 50% of cell binding. At different time points of synchronized phagocytosis (30, 90 and 180 minutes) total RNA was extracted and subjected to microarray analysis. We compared S2 cells in which Eater expression was decreased by RNA interference with control S2 cells exposed to irrelevant double-stranded (pBR322). Three independent experiments were performed corresponding to three biological replicates. Decreased phagocytosis due to RNAi eater knock down was controlled in all cases.
Project description:Dosage compensation refers to the equalization of most X-linked gene products between males and females. In Drosophila, it is mediated by the MSL complex that preferentially associates with numerous sites on the X chromosome in somatic cells of males, and is responsible for an enhancement of the transcriptional rate of a substantial number of X-linked genes. Here we show that topoisomerase II (Topo II) is an integral part of the mechanistic basis of dosage compensation and we highlight a novel function for this enzyme. A widely accepted model of transcription postulates that the moving bubble generated by an RNA polymerase elongating complex induces positive DNA supercoiling in the region ahead of the complex and negative supercoiling in its wake. These transitory changes in supercoiling are resolved by the action of topoisomerases. We have investigated the role of Topo II in dosage compensation by RNAi-mediated depletion, and we have used chromatin immunoprecipitation to determine its genomic distribution and relative abundance on X-linked genes. Topo II is enriched on dosage compensated genes and this enrichment is independent from the approximate two-fold enhancement in transcription of these genes. We have demonstrated an RNA-dependent association of Topo II with MLE, the ATPase-helicase subunit of the MSL complex. Our results indicate a role for Topo II that is additional to and different from its function in restoring normal DNA superhelicity during the transcription process. We suggest that the enhanced level of Topo II alters the DNA supercoiling of compensated gene units to facilitate transcription and could provide a basis for the recent report that the MSL complex enhances transcription by increasing the rate of elongation of RNA polymerase II. Investigation of dosage compensated gene expression levels in S2 and S2 Topo II RNAi knockdown cells. mRNA was isolated from S2 cells and S2 cells with RNAi knockdown of Topo II. The mRNA was then converted to cDNA and hybridized to a NimbleGen D. melanogaster gene expression array. 2 replicates each.
Project description:Heterochromatin-protein 1 (HP1) is a functionally diverse family of proteins. In particular, Drosophila dHP1c forms a complex with the transcription factors WOC and ROW (dHP1EU) that localizes at euchromatin and regulates gene expression. We used microarrays to analyse the changes in gene expression after row depletion by RNAi. For expression profiling analyses, total RNAs were prepared from control S2 cells and upon RNAi-mediated depletion of ROW, converted to cDNA and hybridized to Drosophila Genome 2.0 GeneChip (Affymetrix).