人类染色体重塑PBAF复合体与核细胞结合的结构
Junjie Yuan1,2,3, Kangjing Chen1,2, Wenbo Zhang1,2
1MOE Key Laboratory of Protein Science, Tsinghua University, Beijing, China.
Nature
|April 28, 2022
概括
人类多相关BRG1相关因子 (PBAF) 复合结构揭示了SMARCA4运动子单元如何重塑核细胞. 疾病突变聚集在关键接口,提供对染色体重塑器功能和人类疾病的见解.
科学领域:
- 分子生物学
- 结构生物学
- 遗传学
背景情况:
- 核细胞由DNA包裹的基因组形成,作为获取遗传信息的障碍.
- 类似Snf2的染色体重塑剂利用ATP重新定位核细胞,在染色体交易中发挥关键作用.
研究的目的:
- 确定与核体结合的人类PBAF复合物的冷电子显微镜结构.
- 阐明PBAF复合体核细胞识别和重塑的机制.
- 了解SMARCA4相关的人类疾病的结构基础.
主要方法:
- 电子显微镜 (cryo-EM) 用于确定与核体结合的12个子单元的人类PBAF复合物的结构.
- 综合体内的子单元相互作用和功能接口的分析.
主要成果:
- 该结构显示了SMARCA4运动子单元参与核酶体的活性构造.
- 在SMARCA4中与疾病相关的突变位于染色体重塑的关键接口.
- 在它的Snf2 ATP合 (SnAc) 域中,SMARCA4利用了三种氨酸来结合核酶体的H2A-H2B酸性口袋.
- PBAF复合体表现出模块化,辅助子单元形成核体和基因组尾部结合的叶片,ARID2,PBRM1,PHF10和BRD7发挥了特定的作用.
结论:
- 这项研究提供了PBAF复合体如何识别和重塑核体的机制性见解.
- 这些发现为了解与SMARCA4突变相关的人类疾病提供了结构基础.
- PBAF的模块化组织突出了其子单位之间的功能专业化.
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