Human RAD18 interacts with ubiquitylated chromatin components and facilitates RAD9 recruitment to DNA double strand breaks.
Human RAD18 interacts with ubiquitylated chromatin components and facilitates RAD9 recruitment to DNA double strand breaks.
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DOI：
10.1371/journal.pone.0023155
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发表时间：
2011
期刊：
影响因子：
3.7
通讯作者：
Baarends WM
中科院分区：
文献类型：
--
作者：
Inagaki A;Sleddens-Linkels E;van Cappellen WA;Hibbert RG;Sixma TK;Hoeijmakers JH;Grootegoed JA;Baarends WM
RAD 18是一种参与复制损伤旁路和DNA双链断裂（DSB）修复过程的泛素连接酶。我们发现RPA是细胞周期中RAD 18定位的动态模式所必需的，并且是RAD 18在γ辐射诱导的DNA损伤位点的积累所必需的。此外，在整个细胞周期和照射后，RAD 18与染色质相关的缀合泛素和泛素化H2 A共定位。这种定位模式依赖于一个完整的，泛素结合锌指结构域的存在。使用生物化学方法，我们表明，RAD 18直接结合到泛素化的H2 A和其他几个未知的泛素化染色质成分。这种相互作用也依赖于RAD 18锌指，并且在γ-辐射诱导DSB时增加。有趣的是，RAD 18并不总是与显示增强的H2 A泛素化的区域共定位。在人类女性原代成纤维细胞中，两条X染色体之一失活以平衡男性（XY）和女性（XX）细胞之间的X染色体基因表达，这种失活的X富含泛素化的H2 A，但很少积累RAD 18。这表明RAD 18与泛素化H2 A的结合是上下文依赖性的。关于RAD 18在DSB定位的功能相关性，我们发现RAD 18是将RAD 9（9-1-1检查点复合物的组分之一）募集到这些位点所必需的。RAD 9的募集需要RAD 18的RING和锌指结构域的功能。总之，我们的数据表明，通过泛素化的H2 A和其他泛素化的染色质组分，RAD 18与DSB的关联允许RAD 9的募集，RAD 9可能直接在DSB修复中起作用，而不依赖于检查点激酶CHK 1和CHK 2的下游激活。
RAD18 is an ubiquitin ligase involved in replicative damage bypass and DNA double-strand break (DSB) repair processes. We found that RPA is required for the dynamic pattern of RAD18 localization during the cell cycle, and for accumulation of RAD18 at sites of γ-irradiation-induced DNA damage. In addition, RAD18 colocalizes with chromatin-associated conjugated ubiquitin and ubiquitylated H2A throughout the cell cycle and following irradiation. This localization pattern depends on the presence of an intact, ubiquitin-binding Zinc finger domain. Using a biochemical approach, we show that RAD18 directly binds to ubiquitylated H2A and several other unknown ubiquitylated chromatin components. This interaction also depends on the RAD18 Zinc finger, and increases upon the induction of DSBs by γ-irradiation. Intriguingly, RAD18 does not always colocalize with regions that show enhanced H2A ubiquitylation. In human female primary fibroblasts, where one of the two X chromosomes is inactivated to equalize X-chromosomal gene expression between male (XY) and female (XX) cells, this inactive X is enriched for ubiquitylated H2A, but only rarely accumulates RAD18. This indicates that the binding of RAD18 to ubiquitylated H2A is context-dependent. Regarding the functional relevance of RAD18 localization at DSBs, we found that RAD18 is required for recruitment of RAD9, one of the components of the 9-1-1 checkpoint complex, to these sites. Recruitment of RAD9 requires the functions of the RING and Zinc finger domains of RAD18. Together, our data indicate that association of RAD18 with DSBs through ubiquitylated H2A and other ubiquitylated chromatin components allows recruitment of RAD9, which may function directly in DSB repair, independent of downstream activation of the checkpoint kinases CHK1 and CHK2.
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影响因子：
7.7
作者：
Bomar, Martha G.;Pai, Ming-Tao;Zhou, Pei
通讯作者：
Zhou, Pei
影响因子：
4.8
作者：
Burtelow, MA;Roos-Mattjus, PMK;Karnitz, LM
通讯作者：
Karnitz, LM
影响因子：
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作者：
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RAD18 传递 DNA 损伤信号以引发同源重组修复。
影响因子：
21.3
作者：
Huang, Jun;Huen, Michael S. Y.;Kim, Hongtae;Leung, Charles Chung Yun;Glover, J. N. Mark;Yu, Xiaochun;Chen, Junjie
通讯作者：
Chen, Junjie
影响因子：
16
作者：
Kannouche, PL;Wing, J;Lehmann, AR
通讯作者：
Lehmann, AR