Suppr超能文献

H3.3-H4 四聚体分裂事件的特征是细胞类型特异性增强子。

H3.3-H4 tetramer splitting events feature cell-type specific enhancers.

机构信息

College of Biological Sciences, China Agricultural University, Beijing, China.

出版信息

PLoS Genet. 2013 Jun;9(6):e1003558. doi: 10.1371/journal.pgen.1003558. Epub 2013 Jun 6.

Abstract

Previously, we reported that little canonical (H3.1-H4)(2) tetramers split to form "hybrid" tetramers consisted of old and new H3.1-H(4) dimers, but approximately 10% of (H3.3-H4)2 tetramers split during each cell cycle. In this report, we mapped the H3.3 nucleosome occupancy, the H3.3 nucleosome turnover rate and H3.3 nucleosome splitting events at the genome-wide level. Interestingly, H3.3 nucleosome turnover rate at the transcription starting sites (TSS) of genes with different expression levels display a bimodal distribution rather than a linear correlation towards the transcriptional activity, suggesting genes are either active with high H3.3 nucleosome turnover or inactive with low H3.3 nucleosome turnover. H3.3 nucleosome splitting events are enriched at active genes, which are in fact better markers for active transcription than H3.3 nucleosome occupancy itself. Although both H3.3 nucleosome turnover and splitting events are enriched at active genes, these events only display a moderate positive correlation, suggesting H3.3 nucleosome splitting events are not the mere consequence of H3.3 nucleosome turnover. Surprisingly, H3.3 nucleosomes with high splitting index are remarkably enriched at enhancers in a cell-type specific manner. We propose that the H3.3 nucleosomes at enhancers may be split by an active mechanism to regulate cell-type specific transcription.

摘要

先前,我们报道了小的经典 (H3.1-H4)(2)四聚体分裂形成由旧和新 H3.1-H(4)二聚体组成的“杂交”四聚体,但在每个细胞周期中,大约有 10%的 (H3.3-H4)2 四聚体分裂。在本报告中,我们在全基因组水平上绘制了 H3.3 核小体占有率、H3.3 核小体周转率和 H3.3 核小体分裂事件。有趣的是,不同表达水平基因的转录起始位点(TSS)处的 H3.3 核小体周转率呈双峰分布,而不是与转录活性呈线性相关,这表明基因要么具有高 H3.3 核小体周转率的活性,要么具有低 H3.3 核小体周转率的非活性。H3.3 核小体分裂事件在活性基因中富集,实际上比 H3.3 核小体占有率本身更好地标记活性转录。尽管 H3.3 核小体周转率和分裂事件都在活性基因中富集,但这些事件仅显示出中度正相关,表明 H3.3 核小体分裂事件不是 H3.3 核小体周转率的简单结果。令人惊讶的是,具有高分裂指数的 H3.3 核小体在细胞类型特异性方式中显著富集于增强子。我们提出,增强子处的 H3.3 核小体可能通过一种活跃的机制分裂,以调节细胞类型特异性转录。

https://cdn.ncbi.nlm.nih.gov/pmc/blobs/5824/3675017/94c55f303a8a/pgen.1003558.g001.jpg

文献AI研究员

20分钟写一篇综述,助力文献阅读效率提升50倍。

立即体验

用中文搜PubMed

大模型驱动的PubMed中文搜索引擎

马上搜索

文档翻译

学术文献翻译模型,支持多种主流文档格式。

立即体验