完整的S.S.的结构 脑膜细胞Rpd3S-核酶体复合体
bioRxiv : the preprint server for biology
|August 14, 2023
概括
Rpd3S复杂结构揭示了它如何结合核细胞来调节基因转录. 这种基因素脱乙酶复合物精确地向乙化基因素,确保在酵母中适当控制基因表达.
科学领域:
- 分子生物学分子生物学
- 表观遗传学 在表观遗传学中,表观遗传学是指表观遗传学.
- 结构生物学 结构生物学
背景情况:
- 基因表达调节的关键是基因乙化对基因表达调节至关重要.
- 酵母中的Rpd3S复合物去乙化组织蛋白,以抑制虚假转录.
- 在此之前,Rpd3S复合物的子单元固体测量和核细胞相互作用是未知的.
研究的目的:
- 确定与核细胞结合的完整Rpd3S复合物的冷EM结构.
- 阐明Rpd3S.Rpd3S.Rpd3S.Rpd3S.Rpd3S.Rpd3S.Rpd3S.Rpd3S.Rpd3S.Rpd3S.Rpd3S.Rpd3S.Rpd3S.Rpd3S.Rpd3S.Rpd3S.Rpd3S.Rpd3S.Rpd3S.Rpd3S.Rpd3S.Rpd3S.
- 了解Rpd3S是如何实现基质特异性的.
主要方法:
- 低温电子显微镜 (cryo-EM) 用于确定Rpd3S-核组合的结构.
- 生物化学分析以调查子单元相互作用和基质结合.
主要成果:
- 冷-EM结构显示了完整的Rpd3S复合体,包括五个子单元:Rpd3,Sin3,Rco1,Eaf3和Ume1.1.
- Sin3,两个Rco1和两个Eaf3子单位围绕Rpd3,协调Ume1结合.
- 该复合物与三甲基化H3尾巴 (H3K36me3) 结合,并与核细胞DNA,H2A-H2B酸性补丁和基因素H3.3相互作用.
- Sin3亚单元直接调节与乙化基因素基质的结合,赋予其特异性.
结论:
- 化EM结构阐明了Rpd3S复合体的结构和核细胞结合机制.
- 这提供了关于Rpd3S如何实现基质特异性的洞察力.
- 这些发现推动了我们对基因表达的表观遗传调节的理解.
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