Rad59 regulates association of Rad52 with DNA double-strand breaks

Department of Molecular and Cellular Biology, Beckman Research Institute of the City of Hope Duarte, California, 91010, USA
MicrobiologyOpen (Impact Factor: 2.21). 09/2012; 1(3):285-97. DOI: 10.1002/mbo3.31
Source: PubMed


Homologous recombination among repetitive sequences is an important mode of DNA repair in eukaryotes following acute radiation exposure. We have developed an assay in Saccharomyces cerevisiae that models how multiple DNA double-strand breaks form chromosomal translocations by a nonconservative homologous recombination mechanism, single-strand annealing, and identified the Rad52 paralog, Rad59, as an important factor. We show through genetic and molecular analyses that Rad59 possesses distinct Rad52-dependent and -independent functions, and that Rad59 plays a critical role in the localization of Rad52 to double-strand breaks. Our analysis further suggests that Rad52 and Rad59 act in multiple, sequential processes that determine genome structure following acute exposure to DNA damaging agents.

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    • "The purpose of the current study was to explore the function of RAD59 required for the viability of rad27 null mutant cells. We investigated how four rad59 mutations previously characterized with respect to their effects on SSA [21,27], affected survivorship when combined with a rad27 null mutation. We found that rad59-K166A, which alters an amino acid in a conserved, putative α-helical domain [27,34,35], was synthetically lethal in combination with rad27. "
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