BRCA1亚核位置和酸化状态的动态变化是由DNA损伤引起的
1The Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts 02115, USA.
Cell
|August 8, 1997
概括
在S阶段,BRCA1核焦点对DNA损伤有动态反应. 这些BRCA1复合体与受损的DNA相互作用,这表明它们在复制检查点中的作用.
科学领域:
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
- 遗传学 是一个遗传学.
背景情况:
- 在细胞周期的S阶段,BRCA1蛋白在细胞周期的S阶段形成离散的核焦点.
- 这些BRCA1焦点在应对DNA损伤时的功能尚未完全理解.
研究的目的:
- 为了研究BRCA1焦点在S阶段对DNA损伤的反应中的动态行为.
- 确定BRCA1酸化和相关蛋白在DNA损伤反应中的作用.
- 为了阐明BRCA1复合体在复制检查点中的参与.
主要方法:
- 用基尿素处理MCF7细胞以阻止DNA合成.
- 细胞被暴露在破坏DNA的物质中,如紫外线,菌素C和玛辐射.
- 分析了BRCA1酸化状况,BARD1,Rad51和PCNA局部.
- 在缺乏DNA-PK和ATM激酶的细胞中进行了实验.
主要成果:
- 基尿素诱导的DNA合成停止导致BRCA1焦点分散.
- 紫外线,菌素C和玛辐射也导致BRCA1焦点的损失,独立于DNA合成停止.
- BRCA1酸化变化与焦点损失和DNA损伤相关.
- 在受损时,BRCA1/BARD1/Rad51复合体定位在PCNA+复制结构上.
- 反应发生在缺乏DNA-PK和ATM的细胞中,这表明它们不是主要的介质.
结论:
- BRCA1 S阶段焦点是响应DNA损伤的动态结构.
- 含BRCA1复合体与受损的复制DNA相互作用.
- 这些发现表明BRCA1参与了对DNA损伤的复制检查点反应.
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