A requirement for PARP-1 for the assembly or stability of XRCC1 nuclear foci at sites of oxidative DNA damage
A requirement for PARP-1 for the assembly or stability of XRCC1 nuclear foci at sites of oxidative DNA damage
复制标题
DOI：
10.1093/nar/gkg761
复制
发表时间：
2003-10-01
影响因子：
14.9
通讯作者：
Caldecott, KW
中科院分区：
文献类型：
--
作者：
El-Khamisy, SF;Masutani, M;Caldecott, KW
聚（adp -核糖）聚合酶-1在DNA修复中的分子作用尚不清楚。在这里，我们发现单链断裂修复蛋白XRCC1在poly （adp -核糖）合成位点的DNA氧化损伤后迅速组装成离散的核病灶。在H2O2处理10 min后，聚腺苷核糖（adp -核糖）合成达到峰值，随后不久出现XRCC1聚焦峰。在随后的无药培养基中，poly （adp -核糖）和XRCC1病灶的两个位点都降低到背景水平，这与单链断裂修复过程的快速一致。与PARP-1物理相互作用的XRCC1 BRCT I结构域的突变大大减少了XRCC1在poly （adp -核糖）位点上的病灶形成。此外，我们在H2O2处理后Adprt1(-/-) mef中未能检测到XRCC1灶。这些数据表明，PARP-1是DNA氧化损伤后XRCC1核病灶的组装或稳定性所必需的，并表明这些病灶的形成是通过与聚adp核糖相互作用介导的。这些结果支持了一个模型，即PARP-1在DNA链断裂位点的快速激活通过募集分子支架蛋白XRCC1促进DNA修复。
The molecular role of poly (ADP-ribose) polymerase-1 in DNA repair is unclear. Here, we show that the single-strand break repair protein XRCC1 is rapidly assembled into discrete nuclear foci after oxidative DNA damage at sites of poly (ADP-ribose) synthesis. Poly (ADP-ribose) synthesis peaks during a 10 min treatment with H2O2 and the appearance of XRCC1 foci peaks shortly afterwards. Both sites of poly (ADP-ribose) and XRCC1 foci decrease to background levels during subsequent incubation in drug-free medium, consistent with the rapidity of the single-strand break repair process. The formation of XRCC1 foci at sites of poly (ADP-ribose) was greatly reduced by mutation of the XRCC1 BRCT I domain that physically interacts with PARP-1. Moreover, we failed to detect XRCC1 foci in Adprt1(-/-) MEFs after treatment with H2O2. These data demonstrate that PARP-1 is required for the assembly or stability of XRCC1 nuclear foci after oxidative DNA damage and suggest that the formation of these foci is mediated via interaction with poly (ADP-ribose). These results support a model in which the rapid activation of PARP-1 at sites of DNA strand breakage facilitates DNA repair by recruiting the molecular scaffold protein, XRCC1.