首页 | 本学科首页   官方微博 | 高级检索  
   检索      


ZMYM2 restricts 53BP1 at DNA double-strand breaks to favor BRCA1 loading and homologous recombination
Authors:Doohyung Lee  Katja Apelt  Seong-Ok Lee  Hsin-Ru Chan  Martijn S Luijsterburg  Justin W C Leung  Kyle M Miller
Institution:Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX, 78712, USA;Department of Human Genetics, Leiden University Medical Center, Einthovenweg 20, 2333 ZC Leiden, the Netherlands;Department of Radiation Oncology, College of Medicine, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA;Livestrong Cancer Institutes, Dell Medical School, The University of Texas at Austin, Austin, TX, 78712, USA
Abstract:An inability to repair DNA double-strand breaks (DSBs) threatens genome integrity and can contribute to human diseases, including cancer. Mammalian cells repair DSBs mainly through homologous recombination (HR) and nonhomologous end-joining (NHEJ). The choice between these pathways is regulated by the interplay between 53BP1 and BRCA1, whereby BRCA1 excludes 53BP1 to promote HR and 53BP1 limits BRCA1 to facilitate NHEJ. Here, we identify the zinc-finger proteins (ZnF), ZMYM2 and ZMYM3, as antagonizers of 53BP1 recruitment that facilitate HR protein recruitment and function at DNA breaks. Mechanistically, we show that ZMYM2 recruitment to DSBs and suppression of break-associated 53BP1 requires the SUMO E3 ligase PIAS4, as well as SUMO binding by ZMYM2. Cells deficient for ZMYM2/3 display genome instability, PARP inhibitor and ionizing radiation sensitivity and reduced HR repair. Importantly, depletion of 53BP1 in ZMYM2/3-deficient cells rescues BRCA1 recruitment to and HR repair of DSBs, suggesting that ZMYM2 and ZMYM3 primarily function to restrict 53BP1 engagement at breaks to favor BRCA1 loading that functions to channel breaks to HR repair. Identification of DNA repair functions for these poorly characterized ZnF proteins may shed light on their unknown contributions to human diseases, where they have been reported to be highly dysregulated, including in several cancers.
Keywords:
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号