Promotion of presynaptic filament assembly by the ensemble of S. cerevisiae Rad51 paralogues with Rad52.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 26215801.
- Also identified by DOI 10.1038/ncomms8834 and PMC identifier 4525180.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
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.
Medical subject headings
- Adenosine Triphosphatases
- DNA Repair Enzymes
- DNA, Single-Stranded
- DNA-Binding Proteins
- Rad51 Recombinase
- Rad52 DNA Repair and Recombination Protein
- Recombinational DNA Repair
- Replication Protein A
- Saccharomyces cerevisiae Proteins