人类PARP-1对DNA损伤依赖的ADP-ribosylation的结构基础
Marie-France Langelier1, Jamie L Planck, Swati Roy
1Department of Biochemistry and Molecular Biology, The Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA 19107, USA.
概括
通过DNA损伤激活PARP-1多聚合酶 (PARP-1),涉及到一个崩的PARP-1域结构. 这种DNA诱导的构造破坏了催化域的稳定,增加了激活的蛋白质动态.
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 结构生物学 结构生物学
背景情况:
- 聚ADP-ribose) 聚合酶-1 (PARP-1) 对于修复DNA损伤至关重要.
- 它的激活机制,将DNA损伤检测与酶活性联系起来,仍然不清楚.
- PARP-1 具有模块化域结构,影响其功能.
研究的目的:
- 为了阐明通过DNA双链断裂激活PARP-1的结构机制.
- 了解PARP-1域如何与受损DNA相互作用.
- 揭示导致PARP-1催化活性的构造变化.
主要方法:
- 使用X射线晶体学来确定与DNA双链断裂结合的人类PARP-1域的结构.
- 在DNA结合复合体中对域组织和域间联系进行分析.
主要成果:
- PARP-1以单体的形式与DNA结合.
- 通过域间接触 (Zn1,Zn3,WGR) 的DNA损伤诱导了崩的PARP-1构造.
- 这种构造破坏了催化域 (CAT) 的稳定,增加了其动态.
结论:
- PARP-1的DNA依赖激活是由一个形状变化介导的.
- 由DNA结合诱导的催化域的动态增加是PARP-1激活的基础.
- 这种结构性洞察力为PARP-1在DNA修复中的作用提供了机制性的解释.
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