XRCC1 co-localizes and physically interacts with PCNA
XRCC1 co-localizes and physically interacts with PCNA
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DOI：
10.1093/nar/gkh556
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发表时间：
2004-04-01
影响因子：
14.9
通讯作者：
Wilson, DM
中科院分区：
文献类型：
--
作者：
Fan, JS;Otterlei, M;Wilson, DM
X射线修复交叉互补蛋白1（XRCC1）被认为在碱基切除修复和单链断裂修复（SSBR）中起支架蛋白的作用，因为它与参与这些相关途径的几种蛋白质相互作用，并且没有已知的酶活性。此外，研究表明XRCC1具有离散的G（1）和S相位特异性功能。为了进一步确定XRCC 1对DNA代谢的贡献，我们确定了这种蛋白质的体内定位模式，并寻找新的蛋白质相互作用物。我们在这里报告说，XRCC1共定位与增殖细胞核抗原（PCNA）在DNA复制灶，观察只在未受损的HeLa细胞的S期。此外，荧光共振能量转移（FRET）分析和免疫共沉淀表明，XRCC 1和PCNA是在一个复杂的，可能在体内物理相互作用。体外生化分析表明，这两种蛋白质直接缔合，相互作用由XRCC 1的氨基酸166和310之间的残基介导。目前的证据表明，XRCC 1通过与PCNA相互作用被隔离到DNA复制工厂的位点，以促进S期的有效SSBR。
X-ray Repair Cross Complementing 1 (XRCC1) is thought to function as a scaffolding protein in both base excision repair and single-strand break repair (SSBR), since it interacts with several proteins participating in these related pathways and has no known enzymatic activity. Moreover, studies indicate that XRCC1 possesses discrete G(1) and S phase-specific functions. To further define the contribution of XRCC1 to DNA metabolism, we determined the in vivo localization pattern of this protein and searched for novel protein interactors. We report here that XRCC1 co-localizes with proliferating cell nuclear antigen (PCNA) at DNA replication foci, observed exclusively in the S phase of undamaged HeLa cells. Furthermore, fluorescence resonance energy transfer (FRET) analysis and co-immunoprecipitation indicate that XRCC1 and PCNA are in a complex and likely physically interact in vivo. In vitro biochemical analysis demonstrated that these two proteins associate directly, with the interaction being mediated by residues between amino acids 166 and 310 of XRCC1. The current evidence suggests a model where XRCC1 is sequestered via its interaction with PCNA to sites of DNA replication factories to facilitate efficient SSBR in S phase.