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A Method to Study de novo Formation of Chromatin Domains
Published on: August 23, 2019
赖于希拉的素H3.3沉积促进了在ES细胞的发育位点的PRC2招募
Laura A Banaszynski1, Duancheng Wen2, Scott Dewell3
1Laboratory of Chromatin Biology & Epigenetics, The Rockefeller University, New York, New York, 10065 USA.
Cell
|October 1, 2013
概括
基因组变异H3.3对于聚合体抑制复合体2 (PRC2) 在小鼠胚胎干细胞 (ESC) 中建立基因沉默标记 (H3K27me3) 是必不可少的. H3.3 枯竭减少了 PRC2 结合和 Hira 陪伴物相互作用,影响了分化.
科学领域:
- 表观遗传学和基因调控
- 染色体生物学 染色体生物学
- 发展生物学 发展生物学
背景情况:
- 多镇压复合体2 (PRC2) 对于通过基因素H3氨酸27三甲基化 (H3K27me3) 调节基因表达至关重要.
- 在Drosophila中,多结合点是动态的,并且富含着组素变体H3.3.3.
- 在哺乳动物胚胎干细胞 (ESCs) 中PRC2-介导的基因沉默中H3.3的作用仍然不完全理解.
研究的目的:
- 为了研究基因组变异H3.3在小鼠ESC中的发育基因促进器中PRC2建立H3K27me3标记中的作用.
- 阐明H3.3,PRC2和基因素伴侣Hira在维持染色质状态方面之间的功能关系,这对于差异化至关重要.
主要方法:
- 在小鼠ESC中H3.3的耗尽.
- 使用 de novo 合成的 ヒ斯沉积来测量核细胞周转率.
- 评估PRC2占用率和与Hira在目标基因促进者的相互作用.
- 希拉染色体局部化的分析.
主要成果:
- H3.3的耗尽导致H3K27me3在发育基因促进体的建立减少.
- 在H3.3耗尽后观察到核细胞周转率和PRC2占用率的减少.
- 需要H3.3来实现PRC2和基因素陪伴者Hira之间的相互作用.
- 希拉对染色质的局部化取决于H3.3.3.
结论:
- H3.3对于PRC2在小鼠ESC中正确建立H3K27me3至关重要.
- H3.3 通过与 Hira 基因组 Chaperone 相互作用,促进 PRC2 的招募和功能.
- 这些发现强调了H3.3在维持基因分化过程中基因调节所必需的染色体景观中的关键作用,独立于"活性"染色体状态.
相关概念视频
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