RNF168在H2A/H2AX上无处不在的K13-15驱动DNA损伤信号传递
Francesca Mattiroli1, Joseph H A Vissers, Willem J van Dijk
1Division of Biochemistry and Center for Biomedical Genetics, Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX Amsterdam, The Netherlands.
Cell
|September 18, 2012
概括
在DNA损伤反应过程中,RNF168,而不是RNF8,在K13-15处单双化基因组H2A/H2AX. 这种特定的基因素无所不在化,而不仅仅是无所不在链,对于信号传输至关重要.
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:
- 对双链断裂 (DSB) 的DNA损伤反应 (DDR) 涉及到依赖于全域的信号传递.
- RNF8和RNF168是关键的E3连接酶,通过向H2A和H2AX基因组来启动这种反应.
研究的目的:
- 阐明RNF8和RNF168在DDR期间的基因组无化中的特定作用.
- 确定DSB信号传输中所涉及的精确的无处不在位置和链接.
主要方法:
- 基于RNF8和RNF168RING域的结构性突变发生.
- 在DSB部位分析基因组基化模式 (单基化和K63连接链).
- 使用突变RNF168无法向组织蛋白的功能评估.
主要成果:
- RNF8对核体H2A是不活跃的;RNF168在K13-15.5处催化H2A/H2AX单双化.
- 在RING域中带电的残留物决定了通过RNF8/RNF168.8的核细胞蛋白识别.
- 在K13-15中,K63泛素链与RNF168依赖的单泛素结合,而不是K118-119.
- RNF168能够准基因组,而不仅仅是催化泛素链,对于DDR信号传输至关重要.
结论:
- 在DSB修复过程中,RNF168是主要的E3结合酶,负责在K13-15处的H2A/H2AX单双化.
- 通过RNF168进行的特异性基因素泛基化是下游DDR信号的先决条件,独立于单独的泛基链形成.
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