REV7单体无法参与双链断裂修复和转化合成,但可以抑制线粒错误
Faye M Vassel1, Daniel J Laverty2, Ke Bian1
1Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
International journal of molecular sciences
|November 14, 2023
概括
Rev7蛋白质二分化对于DNA修复和转化合成 (TLS) 是必不可少的,但并非用于所有细胞周期功能. 这项研究揭示了Rev7二分化在维持基因组稳定性方面的关键作用.
科学领域:
- 分子生物学分子生物学
- 遗传学 遗传学 是一个
- 细胞生物学 细胞生物学
背景情况:
- Rev7是调节DNA修复通路的关键蛋白质,包括转化合成 (TLS) 和双链断裂 (DSB) 修复.
- Rev7通过其HORMA域形成同分体,但这种二分化的功能意义尚未完全理解.
研究的目的:
- 研究Rev7二分化在DNA修复和细胞循环调节中的功能重要性.
- 描述Rev7二分化在细胞对DNA损伤剂的反应中的作用.
主要方法:
- 对表达野生型或二元化突变Rev7 (Rev7K44A/R124A/A135D) 的Rev7缺乏细胞的分析.
- 使用光宿主细胞激活试验来评估TLS的熟练程度.
- 评估了DNA修复能力,同源重组和细胞周期进展.
主要成果:
- 野生类型Rev7,但不是二分化突变,在Rev7缺乏细胞中恢复了对X射线和化剂的敏感性,并逆转了olaparib耐药性.
- Rev7二分化突变未能促进填补空隙的TLS和受损的屏蔽功能,导致DSB重组减少和同源重组增加.
- 该二分化突变在细胞循环调节中保留了部分功能,包括与Ran的相互作用和G2/M积累的救援,但不是线粒细胞的进展.
结论:
- Rev7二分化对于其在TLS和DSB修复中的功能至关重要,以及对调节亚纳相促进复合体至关重要.
- 虽然对于某些DNA修复过程至关重要,但Rev7二分化对于通过Ran相互作用进行线粒状组装是部分不可或缺的.
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