Background Bivalent chromatin (BvCR) is characterized by the presence of simultaneous active and repressive modifications on histone H3 proteins. Influencing expression of the genes, BvCR determine cell fate and direc...
Background Bivalent chromatin (BvCR) is characterized by the presence of simultaneous active and repressive modifications on histone H3 proteins. Influencing expression of the genes, BvCR determine cell fate and direct differentiation and lineage commitment in primary T cells and contribute to autoimmunity. Survivin is highly expressed during cell division and in effector Th1 cells contributing to aggravation of autoimmune inflammation. Survivin can physically bind to DNA, specifically to Threonine-3 of histone H3 (1). Thus, functional, and mechanistic data point to a potential chromatin regulatory role for survivin, potentially acting in combination with histone epigenetic modifications (EMs). Objectives The goal of our study is to establish the colocalization of survivin with BvCRs and to deduce functional effects of this collaboration on chromatin organization and gene expression. Methods Chromatin from CD4+ T cells of 14 female subjects was immunoprecipitated with survivin antibodies and histone H3K27ac, H3K27me3, H3K4me3 antibodies, and coupled with DNA sequencing (ChIPseq, Hiseq2000, Illumina). BvCR were identified as exact overlaps of the three histone EM peaks and the overlapping regions were searched for co-localization with survivin using the ‘ChIPPeakAnno' Bioconductor package. Tag counts K27me3>K27ac were defined as inactive/poised BvCR, while tag count K27me310e-5 were selected and scanned through the HOCOMOCO database to identify consensus transcription factor (TF) motifs. TFs co-localized with the BvCD were identified through ReMap database. To identify survivin sensitive genes, CD4 + T cells were treated with survivin inhibitor YM155 and a list of reproducible DEG (log2FC>[0.4], >1 experiment) was mapped and analysed for clustering with BvCR. Results Co-localization of survivin ChIP peaks with individual H3-peaks was si
暂无评论