RAD51C-XRCC3复合体调节了FANCM介导的R循环分辨率,以保护基因组完整性
Satyaranjan Sahoo1, Tarun Nagraj1, Debanjali Bhattacharya1
1Department of Biochemistry, Indian Institute of Science, Bangalore 560012, India.
Science advances
|February 20, 2026
概括
该RAD51C-XRCC3复合物通过解决R环,一种涉及到Fanconi贫血 (FA) 的DNA结构来防止基因组不稳定. 这个复合体与FANCM相互作用,在复制应力期间管理R循环.
科学领域:
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
- 修复DNA修复DNA的修复
背景情况:
- 芬科尼贫血 (FA) 是一种罕见的遗传疾病,导致骨髓衰竭,出生缺陷和易患癌症.
- 在RAD51对应物中的突变与类似FA的疾病和癌症有关,在DNA修复中具有已知的作用,但在复制压力期间的功能不清楚.
研究的目的:
- 调查RAD51对应物,特别是RAD51C-XRCC3 (CX3) 综合体在Fanconi贫血路径和复制应激反应中的作用.
- 阐明CX3复合体影响R循环处理和基因组稳定性的机制.
主要方法:
- 研究了CX3复合体和FANCM之间的相互作用.
- 评估了CX3复合体功能和病理突变 (RAD51C R258H) 对R循环分辨率和基因组不稳定性的影响.
- 研究了CX3复合体在转录复制碰撞 (TRC) 中的作用.
主要成果:
- 在生理和复制压力下,CX3复合体抑制R环,TRC和基因组不稳定性.
- CX3复合物与FANCM物理相互作用,促进其招募到R循环站点进行解决.
- 一种病态的RAD51C突变损害了FANCM相互作用和R循环处理,导致基因组不稳定.
结论:
- CX3复合体通过调解R环耐受性,在Fanconi贫血途径中发挥着至关重要的作用.
- CX3复合物通过FANCM依赖的R循环分辨率防止R循环诱导的基因组不稳定性,独立于其叉维护作用.
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