Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, Massachusetts 01606, USA.
Nat Commun. 2013;4:2084. doi: 10.1038/ncomms3084.
DNA double-strand break repair is essential for maintenance of genome stability. Recent work has implicated a host of chromatin regulators in the DNA-damage response, and although several functional roles have been defined, the mechanisms that control their recruitment to DNA lesions remain unclear. Here we find that efficient double-strand break recruitment of the INO80, SWR-C, NuA4, SWI/SNF and RSC enzymes is inhibited by the non-homologous end-joining machinery, and that their recruitment is controlled by early steps of homologous recombination. Strikingly, we find no significant role for H2A.X phosphorylation in the recruitment of chromatin regulators, but rather their recruitment coincides with reduced levels of H2A.X phosphorylation. Our work indicates that cell cycle position has a key role in DNA repair pathway choice and that recruitment of chromatin regulators is tightly coupled to homologous recombination.
DNA 双链断裂修复对于维持基因组稳定性至关重要。最近的研究表明,许多染色质调节剂参与了 DNA 损伤反应,尽管已经定义了几个功能角色,但控制它们向 DNA 损伤募集的机制尚不清楚。在这里,我们发现 INO80、SWR-C、NuA4、SWI/SNF 和 RSC 酶的有效双链断裂募集被非同源末端连接机制抑制,并且它们的募集受到同源重组早期步骤的控制。引人注目的是,我们发现 H2A.X 磷酸化在染色质调节剂的募集中没有显著作用,而是它们的募集与 H2A.X 磷酸化水平的降低相一致。我们的工作表明,细胞周期位置在 DNA 修复途径选择中起着关键作用,并且染色质调节剂的募集与同源重组紧密耦合。