Publication Type	Academic Article
Authors	Gruver A, Miller K, Rajesh C, Smiraldo P, Kaliyaperumal S, Balder R, Stiles K, Albala J, Pittman D
Journal	Mutagenesis
Volume	20
Issue	6
Pagination	433-40
Date Published	10/19/2005
ISSN	0267-8357
Keywords	Adenosine Triphosphatases, Cross-Linking Reagents, DNA, DNA-Binding Proteins, Rad51 Recombinase
Abstract	Homologous recombination (HR) is a mechanism for repairing DNA interstrand crosslinks and double-strand breaks. In mammals, HR requires the activities of the RAD51 family (RAD51, RAD51B, RAD51C, RAD51D, XRCC2, XRCC3 and DMC1), each of which contains conserved ATP binding sequences (Walker Motifs A and B). RAD51D is a DNA-stimulated ATPase that interacts directly with RAD51C and XRCC2. To test the hypothesis that ATP binding and hydrolysis by RAD51D are required for the repair of interstrand crosslinks, site-directed mutations in Walker Motif A were generated, and complementation studies were performed in Rad51d-deficient mouse embryonic fibroblasts. The K113R and K113A mutants demonstrated a respective 96 and 83% decrease in repair capacity relative to wild-type. Further examination of these mutants, by yeast two-hybrid analyses, revealed an 8-fold reduction in the ability to associate with RAD51C whereas interaction with XRCC2 was retained at a level similar to the S111T control. These cell-based studies are the first evidence that ATP binding and hydrolysis by RAD51D are required for efficient HR repair of DNA interstrand crosslinks.
PubMed ID	16236763