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Mechanistic insights into RAD51-associated protein 1 (RAD51AP1) action in homologous DNA repair.

ABSTRACT: Homologous recombination catalyzed by the RAD51 recombinase is essential for maintaining genome integrity upon the induction of DNA double strand breaks and other DNA lesions. By enhancing the recombinase activity of RAD51, RAD51AP1 (RAD51-associated protein 1) serves a key role in homologous recombination-mediated chromosome damage repair. We show here that RAD51AP1 harbors two distinct DNA binding domains that are both needed for maximal protein activity under physiological conditions. We have finely mapped the two DNA binding domains in RAD51AP1 and generated mutant variants that are impaired in either or both of the DNA binding domains. Examination of these mutants reveals that both domains are indispensable for RAD51AP1 function in cells. These and other results illuminate the mechanistic basis of RAD51AP1 action in homologous DNA repair.

SUBMITTER: Dunlop MH

PROVIDER: S-EPMC3320983 | biostudies-literature | 2012 Apr

REPOSITORIES: biostudies-literature

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Mechanistic insights into RAD51-associated protein 1 (RAD51AP1) action in homologous DNA repair.

Dunlop Myun Hwa MH Dray Eloïse E Zhao Weixing W San Filippo Joseph J Tsai Miaw-Sheue MS Leung Stanley G SG Schild David D Wiese Claudia C Sung Patrick P

The Journal of biological chemistry 20120227 15

Homologous recombination catalyzed by the RAD51 recombinase is essential for maintaining genome integrity upon the induction of DNA double strand breaks and other DNA lesions. By enhancing the recombinase activity of RAD51, RAD51AP1 (RAD51-associated protein 1) serves a key role in homologous recombination-mediated chromosome damage repair. We show here that RAD51AP1 harbors two distinct DNA binding domains that are both needed for maximal protein activity under physiological conditions. We have ...[more]

PMID: 22375013

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