Project description:Histones of higher eukaryotes are assembled into chromatin primarily during DNA replication, but at other times the histone H3.3 variant replaces canonical H3. We introduce a novel strategy for profiling epigenetic patterns based on H3.3 replacement, using microarrays covering about one third of the Drosophila melanogaster genome at 100-bp resolution. Striking patterns of H3.3 replacement were found over active genes and transposons. H3.3 replacement occurs prominently at sites of abundant RNA polymerase II and methylated H3 lysine-4 throughout the genome, and is enhanced on the dosage-compensated male X chromosome. Active genes are depleted of histones at promoters and are enriched in H3.3 from upstream to downstream of transcription units. Based on these findings, we propose that deposition and inheritance of actively modified H3.3 in regulatory regions maintains transcriptionally active chromatin. Keywords: Chromatin affinity-purification on microarray
Project description:Identification of the interaction partners of the protein ecdysoneless (Ecd) in Drosophila melanogaster S2 cells as well as profiling of the changes in binding for mutant, truncated Ecd del34 protein.
Project description:Histone H3 is assembled into nucleosomes during replication but is replaced by the H3.3 variant at sites of active transcription. Thus replacement levels provide a quantitative measure of histone turnover during transcriptional elongation and other active processes in dividing cells. Here we provide new insights into epigenetic regulation with the first genome-wide chromatin profile at 100-bp resolution, based on measurements of H3.3 levels throughout the Drosophila genome. These data are unpublished. Keywords: Chromatin affinity-purification on microarray
