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乌比奎丁诱导的RNF168凝结促进了DNA双链断裂修复
Li-Li Feng1,2,3,4, Shu-Ying Bie5, Zhi-Heng Deng6
1Department of Pathology, Henan Provincial Key Laboratory of Radiation Medicine, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan 450052, China.
概括
在DNA双链断裂 (DSB) 时,RNF168经历液体-液体相分离 (LLPS),增强其修复功能. 这种由K63结合的多比基因引发的凝结,有助于招募像53BP1和BRCA1这样的关键修复因子,以有效修复DSB.
科学领域:
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
- 生物化学 生物化学
背景情况:
- DNA双链断裂 (DSB) 需要快速的修复因子积累.
- 液-液相分离 (LLPS) 越来越被认为是一种促进DSB修复的机制.
- RNF168是一种E3泛素连酶,通过使H2A.X.无处不在发挥作用,在DSB修复中发挥作用.
研究的目的:
- 调查RNF168是否在DSB站点进行LLPS.
- 阐明RNF168LLPS在DNA修复动态和效率中的作用.
主要方法:
- 细胞照射和成像,观察RNF168的凝聚.
- 在试验室用纯化的RNF168.8.进行蛋白质凝聚试验.
- 确定负责凝结的内在无序区域.
- 乌比基化试验用于评估RNF168的催化活性.
- 对DNA修复因子53BP1和BRCA1.1的招募试验.
主要成果:
- 在辐射后和体外,RNF168在核中形成类似液体的冷凝物.
- 一个内在无序的区域 (氨基酸460-550) 对于RNF168的凝结至关重要.
- 与K63结合的多比奎丁链显著增强了RNF168 LLPS.
- RNF168 LLPS增强了H2A.X的无处不在,创造了一个积极的反循环.
- 在RNF168中LLPS缺陷会损害53BP1和BRCA1的招募,并延迟DSB修复.
结论:
- 在DSB站点上,RNF168经历了K63结合的多基触发的LLPS.
- LLPS增强了RNF168的催化活性和修复因子的招募.
- 通过RNF168介导的LLPS对于高效的DNA双链断裂修复至关重要.
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