Autor: |
Ahmed M. Refaat, Mikiyo Nakata, Afzal Husain, Hidetaka Kosako, Tasuku Honjo, Nasim A. Begum |
Jazyk: |
angličtina |
Rok vydání: |
2023 |
Předmět: |
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Zdroj: |
Cell Reports, Vol 42, Iss 3, Pp 112284- (2023) |
Druh dokumentu: |
article |
ISSN: |
2211-1247 |
DOI: |
10.1016/j.celrep.2023.112284 |
Popis: |
Summary: B cells generate functionally different classes of antibodies through class-switch recombination (CSR), which requires classical non-homologous end joining (C-NHEJ) to join the DNA breaks at the donor and acceptor switch (S) regions. We show that the RNA-binding protein HNRNPU promotes C-NHEJ-mediated S-S joining through the 53BP1-shieldin DNA-repair complex. Notably, HNRNPU binds to the S region RNA/DNA G-quadruplexes, contributing to regulating R-loop and single-stranded DNA (ssDNA) accumulation. HNRNPU is an intrinsically disordered protein that interacts with both C-NHEJ and R-loop complexes in an RNA-dependent manner. Strikingly, recruitment of HNRNPU and the C-NHEJ factors is highly sensitive to liquid-liquid phase separation inhibitors, suggestive of DNA-repair condensate formation. We propose that HNRNPU facilitates CSR by forming and stabilizing the C-NHEJ ribonucleoprotein complex and preventing excessive R-loop accumulation, which otherwise would cause persistent DNA breaks and aberrant DNA repair, leading to genomic instability. |
Databáze: |
Directory of Open Access Journals |
Externí odkaz: |
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