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Enhancement of ADP release from the RAD51 presynaptic filament by the SWI5-SFR1 complex.

ABSTRACT: Homologous recombination catalyzed by the RAD51 recombinase eliminates deleterious DNA lesions from the genome. In the presence of ATP, RAD51 forms a nucleoprotein filament on single-stranded DNA, termed the presynaptic filament, to initiate homologous recombination-mediated DNA double-strand break repair. The SWI5-SFR1 complex stabilizes the presynaptic filament and enhances its ability to mediate the homologous DNA pairing reaction. Here we characterize the RAD51 presynaptic filament stabilization function of the SWI5-SFR1 complex using optical tweezers. Biochemical experiments reveal that SWI5-SFR1 enhances ATP hydrolysis by single-stranded DNA-bound RAD51. Importantly, we show that SWI5-SFR1 acts by facilitating the release of ADP from the presynaptic filament. Our results thus provide mechanistic understanding of the function of SWI5-SFR1 in RAD51-mediated DNA recombination.

SUBMITTER: Su GC

PROVIDER: S-EPMC3874192 | biostudies-literature | 2014 Jan

REPOSITORIES: biostudies-literature

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Enhancement of ADP release from the RAD51 presynaptic filament by the SWI5-SFR1 complex.

Su Guan-Chin GC Chung Chan-I CI Liao Chia-Yu CY Lin Sheng-Wei SW Tsai Cheng-Ting CT Huang Tao T Li Hung-Wen HW Chi Peter P

Nucleic acids research 20130927 1

Homologous recombination catalyzed by the RAD51 recombinase eliminates deleterious DNA lesions from the genome. In the presence of ATP, RAD51 forms a nucleoprotein filament on single-stranded DNA, termed the presynaptic filament, to initiate homologous recombination-mediated DNA double-strand break repair. The SWI5-SFR1 complex stabilizes the presynaptic filament and enhances its ability to mediate the homologous DNA pairing reaction. Here we characterize the RAD51 presynaptic filament stabiliza ...[more]

PMID: 24078249

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