DNA binding and RAD51 engagement by the BRCA2 C-terminus orchestrate DNA repair and replication fork preservation

Abstract

The tumor suppressor BRCA2 participates in DNA double-strand break repair by RAD51-dependent homologous recombination and protects stressed DNA replication forks from nucleolytic attack. We demonstrate that the C-terminal Recombinase Binding (CTRB) region of BRCA2, encoded by gene exon 27, harbors a DNA binding activity. CTRB alone stimulates the DNA strand exchange activity of RAD51 and permits the utilization of RPA-coated ssDNA by RAD51 for strand exchange. Moreover, CTRB functionally synergizes with the Oligonucleotide Binding fold containing DNA binding domain and BRC4 repeat of BRCA2 in RPA-RAD51 exchange on ssDNA. Importantly, we show that the DNA binding and RAD51 interaction attributes of the CTRB are crucial for homologous recombination and protection of replication forks against MRE11-mediated attrition. Our findings shed light on the role of the CTRB region in genome repair, reveal remarkable functional plasticity of BRCA2, and help explain why deletion of Brca2 exon 27 impacts upon embryonic lethality.

Document Details

Document Type
Pub Defense Publication
Publication Date
Jan 26, 2023
Source ID
10.1038/s41467-023-36211-x

Entities

People

  • Aida Badamchi Shabestari
  • Ajinkya S. Kawale
  • Akhilesh K. Singh
  • Alexander Mazin
  • Bipasha Mukherjee
  • Claudia Wiese
  • Claus Sorensen
  • Cody M. Rogers
  • Francisco Neal
  • Heike I Rösner
  • Jeffrey N. Katz
  • Lucy Lu
  • Marina Z. Joel
  • Patrick Sung
  • Platonas N Selemenakis
  • Robert Hromas
  • Sandeep Burma
  • Stephen P. Holloway
  • Valdemaras Petrosius
  • Weixing Zhao
  • Youngho Kwon
  • Zhuoling He

Organizations

  • American Chemical Society
  • Cancer Prevention and Research Institute of Texas
  • Congressionally Directed Medical Research Programs
  • Danish Cancer Society
  • National Institutes of Health
  • United States Department of Health and Human Services

Tags

Fields of Study

  • Biology

Readers

  • Molecular Genetics
  • Molecular and genetic basis of cancer.

Technology Areas

  • Biotechnology