Promotion of Presynaptic Filament Assembly by the Ensemble of S. Cerevisiae Rad51 Paralogues With Rad52

Nat Commun. 2015 Jul 28;6:7834. doi: 10.1038/ncomms8834.

Abstract

The conserved budding yeast Rad51 paralogues, including Rad55, Rad57, Csm2 and Psy3 are indispensable for homologous recombination (HR)-mediated chromosome damage repair. Rad55 and Rad57 are associated in a heterodimer, while Csm2 and Psy3 form the Shu complex with Shu1 and Shu2. Here we show that Rad55 bridges an interaction between Csm2 with Rad51 and Rad52 and, using a fully reconstituted system, demonstrate that the Shu complex synergizes with Rad55-Rad57 and Rad52 to promote nucleation of Rad51 on single-stranded DNA pre-occupied by replication protein A (RPA). The csm2-F46A allele is unable to interact with Rad55, ablating the ability of the Shu complex to enhance Rad51 presynaptic filament assembly in vitro and impairing HR in vivo. Our results reveal that Rad55-Rad57, the Shu complex and Rad52 act as a functional ensemble to promote Rad51-filament assembly, which has important implications for understanding the role of the human RAD51 paralogues in Fanconi anaemia and cancer predisposition.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Adenosine Triphosphatases / metabolism*
  • Cell Cycle Proteins / metabolism
  • DNA Repair Enzymes / metabolism*
  • DNA, Single-Stranded / metabolism*
  • DNA-Binding Proteins / metabolism*
  • In Vitro Techniques
  • Microscopy, Electron
  • Nuclear Proteins / metabolism
  • Rad51 Recombinase / metabolism*
  • Rad52 DNA Repair and Recombination Protein / metabolism*
  • Recombinational DNA Repair*
  • Replication Protein A / metabolism*
  • Saccharomyces cerevisiae
  • Saccharomyces cerevisiae Proteins / metabolism*
  • Schizosaccharomyces pombe Proteins / metabolism

Substances

  • Cell Cycle Proteins
  • Csm2 protein, S cerevisiae
  • DNA, Single-Stranded
  • DNA-Binding Proteins
  • Nuclear Proteins
  • PSY3 protein, S cerevisiae
  • RAD52 protein, S cerevisiae
  • RAD55 protein, S cerevisiae
  • Rad52 DNA Repair and Recombination Protein
  • Replication Protein A
  • Saccharomyces cerevisiae Proteins
  • Schizosaccharomyces pombe Proteins
  • Shu1 protein, S cerevisiae
  • shu2 protein, S cerevisiae
  • RAD51 protein, S cerevisiae
  • Rad51 Recombinase
  • Adenosine Triphosphatases
  • RAD57 protein, S cerevisiae
  • DNA Repair Enzymes