1. Academic Validation
  2. METTL3 and N6-Methyladenosine Promote Homologous Recombination-Mediated Repair of DSBs by Modulating DNA-RNA Hybrid Accumulation

METTL3 and N6-Methyladenosine Promote Homologous Recombination-Mediated Repair of DSBs by Modulating DNA-RNA Hybrid Accumulation

  • Mol Cell. 2020 Aug 6;79(3):425-442.e7. doi: 10.1016/j.molcel.2020.06.017.
Canfeng Zhang 1 Liping Chen 1 Di Peng 2 Ao Jiang 3 Yunru He 1 Yanru Zeng 2 Chen Xie 1 Haoxian Zhou 1 Xiaotong Luo 2 Haiying Liu 1 Liang Chen 3 Jian Ren 2 Wengong Wang 4 Yong Zhao 5
Affiliations

Affiliations

  • 1 MOE Key Laboratory of Gene Function and Regulation, School of Life Sciences, Sun Yat-sen University, Guangzhou 510006, China.
  • 2 MOE Key Laboratory of Gene Function and Regulation, School of Life Sciences, Sun Yat-sen University, Guangzhou 510006, China; State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou 510006, China.
  • 3 Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan 430072, China.
  • 4 Department of Biochemistry and Molecular Biology, Beijing Key Laboratory of Protein Posttranslational Modifications and Cell Function, School of Basic Medical Sciences, Peking University Health Science Center, 38 Xueyuan Road, Beijing 100191, China.
  • 5 MOE Key Laboratory of Gene Function and Regulation, School of Life Sciences, Sun Yat-sen University, Guangzhou 510006, China; State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou 510006, China. Electronic address: zhaoy82@mail.sysu.edu.cn.
Abstract

Double-strand breaks (DSBs) are the most deleterious DNA lesions, which, if left unrepaired, may lead to genome instability or cell death. Here, we report that, in response to DSBs, the RNA methyltransferase METTL3 is activated by ATM-mediated phosphorylation at S43. Phosphorylated METTL3 is then localized to DNA damage sites, where it methylates the N6 position of adenosine (m6A) in DNA damage-associated RNAs, which recruits the m6A reader protein YTHDC1 for protection. In this way, the METTL3-m6A-YTHDC1 axis modulates accumulation of DNA-RNA hybrids at DSBs sites, which then recruit RAD51 and BRCA1 for homologous recombination (HR)-mediated repair. METTL3-deficient cells display defective HR, accumulation of unrepaired DSBs, and genome instability. Accordingly, depletion of METTL3 significantly enhances the sensitivity of Cancer cells and murine xenografts to DNA damage-based therapy. These findings uncover the function of METTL3 and YTHDC1 in HR-mediated DSB repair, which may have implications for Cancer therapy.

Keywords

ATM; DDR; DNA-RNA hybrids; DSB; METTL3; YTHDC1; cancer therapy; genome stability; homologous recombination; m6A.

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