2. Academic Validation
  3. The DNA-binding activity of USP1-associated factor 1 is required for efficient RAD51-mediated homologous DNA pairing and homology-directed DNA repair

The DNA-binding activity of USP1-associated factor 1 is required for efficient RAD51-mediated homologous DNA pairing and homology-directed DNA repair

  • J Biol Chem. 2020 Jun 12;295(24):8186-8194. doi: 10.1074/jbc.RA120.013714.
Fengshan Liang 1 2,  Adam S Miller 1,  Caroline Tang 2 3,  David Maranon 4,  Elizabeth A Williamson 5,  Robert Hromas 5,  Claudia Wiese 4,  Weixing Zhao 6,  Patrick Sung 7,  Gary M Kupfer 8 3
Affiliations

Affiliations

  • 1 Department of Molecular Biophysics and Biochemistry, Yale University School of Medicine, New Haven, Connecticut, USA.
  • 2 Department of Pediatrics, Section of Hematology-Oncology, Yale University School of Medicine, New Haven, Connecticut, USA.
  • 3 Department of Pathology, Yale University School of Medicine, New Haven, Connecticut, USA.
  • 4 Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, Colorado, USA.
  • 5 Department of Medicine, University of Texas Health Science Center at San Antonio, San Antonio, Texas, USA.
  • 6 Department of Biochemistry and Structural Biology, University of Texas Health Science Center at San Antonio, San Antonio, Texas, USA.
  • 7 Department of Biochemistry and Structural Biology, University of Texas Health Science Center at San Antonio, San Antonio, Texas, USA [email protected] [email protected].
  • 8 Department of Pediatrics, Section of Hematology-Oncology, Yale University School of Medicine, New Haven, Connecticut, USA [email protected] [email protected].
PMID: 32350107 DOI: 10.1074/jbc.RA120.013714
Abstract

USP1-associated factor 1 (UAF1) is an integral component of the RAD51-associated protein 1 (RAD51AP1)-UAF1-ubiquitin-specific peptidase 1 (USP1) trimeric Deubiquitinase complex. This complex acts on DNA-bound, monoubiquitinated Fanconi anemia complementation group D2 (FANCD2) protein in the Fanconi anemia pathway of the DNA damage response. Moreover, RAD51AP1 and UAF1 cooperate to enhance homologous DNA pairing mediated by the recombinase RAD51 in DNA repair via the homologous recombination (HR) pathway. However, whereas the DNA-binding activity of RAD51AP1 has been shown to be important for RAD51-mediated homologous DNA pairing and HR-mediated DNA repair, the role of DNA binding by UAF1 in these processes is unclear. We have isolated mutant UAF1 variants that are impaired in DNA binding and tested them together with RAD51AP1 in RAD51-mediated HR. This biochemical analysis revealed that the DNA-binding activity of UAF1 is indispensable for enhanced RAD51 recombinase activity within the context of the UAF1-RAD51AP1 complex. In cells, DNA-binding deficiency of UAF1 increased DNA damage sensitivity and impaired HR efficiency, suggesting that UAF1 and RAD51AP1 have coordinated roles in DNA binding during HR and DNA damage repair. Our findings show that even though UAF1's DNA-binding activity is redundant with that of RAD51AP1 in FANCD2 deubiquitination, it is required for efficient HR-mediated chromosome damage repair.

Keywords

DNA damage; DNA damage response; DNA repair; DNA-binding protein; Fanconi anemia; UAF1–RAD51AP1; deubiquitination; homologous recombination; interstrand cross-linking (ICL); ubiquitin-specific peptidase 1 (USP1).

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