Biochemical analysis of the human EVL domains in homologous recombination

EVL is a member of the ENA/VASP family, which is involved in actin-remodeling processes. Previously, we reported that human EVL directly interacts with RAD51, which is an essential protein in the homologous recombinational repair of DNA double-strand breaks, and stimulates RAD51-mediated recombination reactions in vitro. To identify the EVL domain required for the recombination function, we purified the EVL fragments EVL(1-221) and EVL(222-418), which contain the EVH1 and Pro-rich domains and the EVH2 domain, respectively. We found that EVL(222-418) possesses DNA-binding and RAD51-binding activities, and also stimulates RAD51-mediated homologous pairing. In contrast, EVL(1-221) did not exhibit any of these activities. Therefore, the EVH2 domain, which is highly conserved among the ENA/VASP family proteins, may be responsible for the recombination function of EVL.