Project description:We report here the genome-wide localization of the histone acetyltransferase MYST5 (cg1984) in Drosophila. ChIP-seq analysis was performed with two anti-MYST5 antibodies in S2 cells. We found MYST5 to bind to the promoters of actively transcribed genes. MYST5 furthermore showed extensive colocalization with boundary/ insulator factors, including Chriz/ Chromator, CP190, dCTCF and BEAF-32, which mediate the organization of the genome into functionally distinct topological domains. Altogether, our data suggest a broad role for MYST5 both in gene-specific transcriptional regulation and in the organization of the genome into chromatin domains. Examination of genome-wide MYST5 localization in S2 cells
Project description:We report here the genome-wide localization of the histone acetyltransferase MYST5 (cg1984) in Drosophila. ChIP-seq analysis was performed with two anti-MYST5 antibodies in S2 cells. We found MYST5 to bind to the promoters of actively transcribed genes. MYST5 furthermore showed extensive colocalization with boundary/ insulator factors, including Chriz/ Chromator, CP190, dCTCF and BEAF-32, which mediate the organization of the genome into functionally distinct topological domains. Altogether, our data suggest a broad role for MYST5 both in gene-specific transcriptional regulation and in the organization of the genome into chromatin domains.
2016-02-23 | GSE66212 | GEO
Project description:Polycomb chromatin domains in Drosophila
Project description:We report the evolutionary behaviour of Polycomb group proteins, their recruitment factors and their underlying sequences by performing ChIP-seq analysis in 4-5 different Drosophila species. We demonstrate an extremely high conservation of Polycomb repressive domains across Drosophila species We validate few cases of PRE divergence that shows that cis-driven PRE evolution is a rare event. We further show that PHO recruitment to Polycomb domains is evolutionarily robust to motif changes and that PRC1 stabilizes binding of its key recruiter ChIP-seq analysis of histone marks and chromatin associated factors across 4-5 Drosophila species
Project description:Interphase chromatin is organized into topologically associating domains (TADs). Within TADs, chromatin looping interactions are formed between DNA regulatory elements, but their functional importance for the establishment of the 3D genome organization and gene regulation during development is unclear. Using high-resolution Hi-C experiments, we analyze higher order 3D chromatin organization during Drosophila embryogenesis and identify active and repressive chromatin loops that are established with different kinetics and depend on distinct factors: Zelda-dependent active loops are formed before the midblastula transition between transcribed genes over long distances. Repressive loops within polycomb domains are formed after the midblastula transition between polycomb response elements by the action of GAGA factor and polycomb proteins. Perturbation of PRE function by CRISPR/Cas9 genome engineering affects polycomb domain formation and destabilizes polycomb-mediated silencing. Preventing loop formation without removal of polycomb components also decreases silencing efficiency, suggesting that chromatin architecture can play instructive roles in gene regulation during development.
Project description:CpG islands (CGIs) are key DNA regulatory elements in the vertebrate genome and are often found at gene promoters. In mammalian embryonic stem (ES) cells, CGIs are decorated by either the active or repressive histone marks, H3K4me3 and H3K27me3, respectively, or by both modifications (‘bivalent domains’), but their precise regulation is incompletely understood. Remarkably, we find that the polycomb repressive complex 2 (PRC2)-associated protein C17orf96 (a.k.a. esPRC2p48 and E130012A19Rik) is present at most CGIs in mouse ES cells. At PRC2-rich CGIs, loss of C17orf96 results in an increased chromatin binding of Suz12 and elevated H3K27me3 levels concomitant with gene repression. In contrast, at PRC2-poor CGIs, located at actively transcribed genes, C17orf96 colocalizes with RNA polymerase II and its depletion leads to a focusing of H3K4me3 in the core of CGIs. Our findings thus identify C17orf96 as a novel context-dependent CGI regulator. ChIP-seq of C17orf96, H3K4me3 and H3K27me3 in mouse ES cells (E14).
Project description:We report the evolutionary behaviour of Polycomb group proteins, their recruitment factors and their underlying sequences by performing ChIP-seq analysis in 4-5 different Drosophila species. We demonstrate an extremely high conservation of Polycomb repressive domains across Drosophila species We validate few cases of PRE divergence that shows that cis-driven PRE evolution is a rare event. We further show that PHO recruitment to Polycomb domains is evolutionarily robust to motif changes and that PRC1 stabilizes binding of its key recruiter
Project description:Polycomb repressive complexes are important histone modifiers, which silence gene expression, yet there exists a subset of polycomb-bound genes actively transcribed by RNA polymerase II. To investigate the switching between polycomb-repressed and active states, we sequence mRNA from OS25 mouse embryonic stem cells cultured in serum/LIF. To validate our finding that polycomb modulates stochastic gene expression and transcriptional bursting, we perform knockout experiments and we sequence mRNA from Ring1A knockout (untreated) and Ring1A/B double knockout cells with constitutive Ring1A knockout and tamoxifen-inducible conditional Ring1B knockout.
Project description:We report the evolutionary behaviour of Polycomb group proteins, their recruitment factors and their underlying sequences by performing ChIP-seq analysis in 4-5 different Drosophila species (GSE60428) and HiC analysis in Drosophila melanogaster. We demonstrate an extremely high conservation of Polycomb repressive domains across Drosophila species We validate few cases of PRE divergence that shows that cis-driven PRE evolution is a rare event. We further show that PHO recruitment to Polycomb domains is evolutionarily robust to motif changes and that PRC1 stabilizes binding of its key recruiter HiC experiments in wild type drosophila embryos