Retention but not recruitment of Crb2 at double-strand breaks requires Rad1 and Rad3 complexes
Retention but not recruitment of Crb2 at double-strand breaks requires Rad1 and Rad3 complexes
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DOI：
10.1128/mcb.23.17.6150-6158.2003
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发表时间：
2003-09-01
影响因子：
5.3
通讯作者：
Russell, P
中科院分区：
文献类型：
--
作者：
Du, LL;Nakamura, TM;Russell, P
与芽殖酵母Rad 9和人53 BP 1和BRCA 1相关的裂殖酵母检查点蛋白Crb 2已被认为充当衔接蛋白，促进Rad 3-ad 26激酶对特定底物的磷酸化。为了进一步了解它在检查点信号传导中的作用，我们通过使用荧光显微镜检查了它在活细胞中的定位。在DNA损伤的反应中，Crb 2定位于不同的核灶，代表DNA双链断裂（DSB）的位点。Crb 2与Rad 22共定位于持久病灶，表明Crb 2在修复过程中保留在DNA损伤位点。损伤诱导的Crb 2病灶仍然在Rad 1，Rad 3和Rad 17复合物缺陷的细胞中形成，但这些病灶不像野生型细胞那样持久。我们的研究结果表明，Crb 2的功能，在网站的DNA损伤，其调节的持久定位在损伤位点可能参与促进DNA修复和/或维持检查点逮捕，而DNA修复正在进行中。
The fission yeast checkpoint protein Crb2, related to budding yeast Rad9 and human 53BP1 and BRCA1, has been suggested to act as an adapter protein facilitating the phosphorylation of specific substrates by Rad3-ad26 kinase. To further understand its role in checkpoint signaling, we examined its localization in live cells by using fluorescence microscopy. In response to DNA damage, Crb2 localizes to distinct nuclear foci, which represent sites of DNA double-strand breaks (DSBs). Crb2 colocalizes with Rad22 at persistent foci, suggesting that Crb2 is retained at sites of DNA damage during repair. Damage-induced Crb2 foci still form in cells defective in Rad1, Rad3, and Rad17 complexes, but these foci do not persist as long as in wild-type cells. Our results suggest that Crb2 functions at the sites of DNA damage, and its regulated persistent localization at damage sites may be involved in facilitating DNA repair and/or maintaining the checkpoint arrest while DNA repair is under way.