Rad52 promotes postinvasion steps of meiotic double-strand-break repair.
During DNA double-strand-break (DSB) repair by recombination, the broken chromosome uses a homologous chromosome as a repair template. Early steps of recombination are well characterized: DSB ends assemble filaments of RecA-family proteins that catalyze homologous pairing and strand-invasion reactions. By contrast, the postinvasion steps of recombination are poorly characterized. Rad52 plays an essential role during early steps of recombination by mediating assembly of a RecA homolog, Rad51, into nucleoprotein filaments. The meiosis-specific RecA-homolog Dmc1 does not show this dependence, however. By exploiting the Rad52 independence of Dmc1, we reveal that Rad52 promotes postinvasion steps of both crossover and noncrossover pathways of meiotic recombination in Saccharomyces cerevisiae. This activity resides in the N-terminal region of Rad52, which can anneal complementary DNA strands, and is independent of its Rad51-assembly function. Our findings show that Rad52 functions in temporally and biochemically distinct reactions and suggest a general annealing mechanism for reuniting DSB ends during recombination.
Lao
Jessica P
JP
Section of Microbiology, University of California, Davis, One Shields Avenue, Davis, CA 95616, USA.
Oh
Steve D
SD
Shinohara
Miki
M
Shinohara
Akira
A
Hunter
Neil
N
D018797:Cell Cycle Proteins / Q000235:genetics / Q000378:metabolism; D053903:DNA Breaks, Double-Stranded; D004249:DNA Damage; D004260:DNA Repair; D004271:DNA, Fungal / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D006801:Humans; D008540:Meiosis / Q000235:genetics*; D009690:Nucleic Acid Conformation; D051135:Rad51 Recombinase / Q000235:genetics / Q000378:metabolism; D051721:Rad52 DNA Repair and Recombination Protein / Q000235:genetics / Q000378:metabolism*; D011995:Recombination, Genetic; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism*
D018797:Cell Cycle Proteins; C513033:DMC1 protein, S cerevisiae; D004271:DNA, Fungal; D004268:DNA-Binding Proteins; C497197:RAD52 protein, S cerevisiae; D051721:Rad52 DNA Repair and Recombination Protein; D029701:Saccharomyces cerevisiae Proteins; C495151:RAD51 protein, S cerevisiae; D051135:Rad51 Recombinase