Project description:WS234 cells are an immortalized human cell line. Here we have explored the distribution of histone marks (H3K27me3, H3K27ac, H3K4me3, H3K4me1, and H3K9me3) across the genome in proliferative conditions.
Project description:We performed the newly mapping of genome-wide NFATc1 binding events in VEGF-stimulated primary cultured endothelial cells, by chromatin immunoprecipitation followed by high-throughput sequencing (ChIP-seq). Combined NFATc1 ChIP-seq profile and the epigenetic histone marks revealed that predominant NFATc1-occupied peaks were overlapped with promoter marking but not silencer marking. DNA microarrays with NFATc1 expression or knockdown indicated the predominant NFATc1 binding targets were correlated with induced patterns. Examination of NFATc1 and two different histone marks in HUVEC in the presence/absense of VEGF.
Project description:Lysine methylation is part of the posttranscriptional histone code employed to recruit modification specific readers to chromatin. Unbiased, quantitative mass spectrometry approaches combined with peptide pull-downs have been used to study histone methylation-dependent binders in mammalian cells. Here, we extend the study to birds by investigating the interaction partners for H3K4me3, H3K9me3, H3K27me3 and H3K36me3 in chicken (gallus gallus) and zebra finch (taeniopygia guttata) using label free quantitative proteomics. In general, we find very strong overlap in interaction partners for the trimethyl marks in birds compared to mammals, underscoring the known conserved function of these modifications. In agreement with their epigenetic role, we find binding of PHF2 and members of the TFIID, SAGA, SET1 and NURF complex to the activation mark H3K4me3. Our data furthermore supports the existence of a LID complex in vertebrates recruited to the H3K4me3. The repressive marks are bound by the HP1 proteins and the EED subunit of the PRC2 complex as well as by WIZ. Like the screens in mammals, we found ZNF462, ZNF828 and POGZ enriched at H3K9me3. However, we noted some unexpected differences. First, we did not observe the enrichment of CDYL and CDYL2 at the repressive marks. Second N-PAC (also known as GLYR1), an H3K36me3 interactor in mammals, is not binding to this modification in our screen. This suggests that despite strong conservation of the histone tail sequence, species-specific differences in epigenetic readers may have evolved.
Project description:Epigenetic states defined by chromatin can be maintained through mitotic cell division. However, it remains unknown how histone-based information is transmitted. Here we combine nascent chromatin capture (NCC) and triple-SILAC labelling to track histone modifications and histone variants during DNA replication and across the cell cycle. We show that post-translational modifications (PTMs) are transmitted with parental histones to newly replicated DNA. Di- and tri-methylation marks are diluted two-fold upon DNA replication, as a consequence of new histone deposition. Importantly, within one cell cycle all PTMs are restored. In general, new histones are modified to mirror the parental histones. However, H3K9me3 and H3K27me3 are propagated by continuous modification of parental and new histones, because the establishment of these marks extends over several cell generations. Together, our results reveal how histone marks propagate and demonstrate that chromatin states oscillate within the cell cycle.
Project description:Expression profiling of proliferating primary myoblasts obtained from vastus lateralis muscle biopsises from healthy individuals and stimulated with Vitamin D (100 nM 1,25(OH)2D3) or vehicle for 24h.