Distinct roles of the two BRCA2 DNA-binding domains in DNA damage repair and replication fork preservation
Homologous recombination (HR) removes DNA double-strand breaks (DSBs) and preserves stressed DNA replication forks. Successful HR execution requires the tumor suppressor BRCA2, which harbors distinct DNA-binding domains (DBDs): one that possesses three oligonucleotide/oligosaccharide-binding (OB) folds (OB-DBD) and another residing in the C-terminal recombinase binding domain (CTRB-DBD). Here, we employ multi-faceted approaches to delineate the contributions of these domains toward HR and replication fork maintenance. We show that OB-DBD and CTRB-DBD confer single-strand DNA (ssDNA)- and dsDNA-binding capabilities, respectively, and that BRCA2 variants mutated in either domain are impaired in their ability to load the recombinase RAD51 onto ssDNA pre-occupied by RPA. While the CTRB-DBD mutant is modestly affected by DNA break repair, it exhibits a strong defect in the protection of stressed replication forks. In contrast, the OB-DBD is indispensable for both BRCA2 functions. Our study thus defines the unique contributions of the two BRCA2 DBDs in genome maintenance.
Authors
- Youngho Kwon (ORCID: https://orcid.org/0000-0002-0287-8795)
- Eloïse Dray (ORCID: https://orcid.org/0000-0001-6793-9838)
- Robert Hromas (ORCID: https://orcid.org/0000-0002-1916-6276)
- Jeffrey N. Katz (ORCID: https://orcid.org/0000-0003-2104-4670)
- Claus Storgaard Sørensen (ORCID: https://orcid.org/0000-0001-6022-9710)
- David S. Libich (ORCID: https://orcid.org/0000-0001-6492-2803)
- Shaun K. Olsen (ORCID: https://orcid.org/0000-0002-1265-7101)
- Francisco Neal (ORCID: https://orcid.org/0000-0001-7676-8997)
- Sandeep Burma (ORCID: https://orcid.org/0000-0001-7057-9845)
- Arijit Dutta (ORCID: https://orcid.org/0000-0002-5675-0092)
- Alexander V. Mazin (ORCID: https://orcid.org/0000-0002-5430-9797)
- Elizabeth V. Wasmuth (ORCID: https://orcid.org/0000-0003-1474-4935)
- Mollie E. Uhrig (ORCID: https://orcid.org/0000-0002-4142-8260)
- Claudia Wiese (ORCID: https://orcid.org/0000-0001-6844-4693)
- Patrick Sung (ORCID: https://orcid.org/0000-0003-1396-9040)
- Wenjing Li (ORCID: https://orcid.org/0000-0001-9151-9219)
- Weixing Zhao (ORCID: https://orcid.org/0000-0001-5746-3696)
- Neelam Sharma (ORCID: https://orcid.org/0000-0003-0670-2188)
- Shahrez Syed
Institutions
- University of Copenhagen (DK)
- The University of Texas at San Antonio Health Science Center (US)
- The University of Texas at San Antonio (US)
- Colorado State University (US)
Publication Details
- Journal
- Cell Reports
- Published
- 2025-05-01
- DOI
- https://doi.org/10.1016/j.celrep.2025.115654
- Citations
- 4
- Primary Topic
- DNA Repair Mechanisms
- Type
- article
- Field-Weighted Citation Impact
- 3.22
Funders
- American Cancer Society
- Cancer Prevention and Research Institute of Texas
- Kræftens Bekæmpelse
- National Institutes of Health
- Congressionally Directed Medical Research Programs