Rad50钉是一种结构,在DNA重组和修复过程中连接Mre11复合体
Karl-Peter Hopfner1, Lisa Craig, Gabriel Moncalian
1[1] Department of Molecular Biology and Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, California 92037, USA [2] Gene Center and Institute of Biochemistry, University of Munich, 81377 Munich, Germany.
Nature
|August 2, 2002
概括
Mre11复合体使用Rad50卷轴来桥接DNA,这对于染色体维护和DNA修复至关重要. 这种结构洞察力揭示了Rad50如何将DNA结合头与同源重组等过程联系起来.
科学领域:
- 分子生物学分子生物学
- 结构生物学 结构生物学
- 遗传学 是一个遗传学.
背景情况:
- Mre11复合体 (Mre11 Rad50 Nbs1) 对于DNA修复和染色体稳定性至关重要.
- 它在同源重组和端粒维护中的功能表明它在链接DNA基质中的作用,但机制尚不清楚.
研究的目的:
- 阐明Mre11复合物连接DNA基质的分子机制.
- 为了确定Rad50元件的桥梁功能的结构基础.
主要方法:
- 在Rad50卷轴-卷轴区域的X射线晶体 (2.2A分辨率).
- 生物化学测试. 生物化学测试.
- 电子显微镜. 电子显微镜.
主要成果:
- 在Rad50卷轴的顶部发现了一种新型的二极体接口,它具有相互锁定的Cys-X-X-Cys图案,结合一个Zn2+) 离子.
- 这些图案形成了高达1200A的灵活桥梁,连接Rad50卷轴-卷轴域.
- Rad50头基因的突变导致酵母对辐射敏感,并损害了Mre11结合.
结论:
- 拉德50线圈作为建筑元素,在DNA结合头之间形成金属介导的桥梁.
- 这些结构被建议在同源重组中将姐妹染色体连接起来,而DNA末端在非同源末端连接中.
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