Vav and Vav2 are members of the Dbl family of proteins that act as guanine nucleotide
exchange factors (GEFs) for Rho family proteins. Whereas Vav expression is restricted to
cells of hematopoietic origin, Vav2 is widely expressed. Although Vav and Vav2 share highly
related structural similarities and high sequence identity in their Dbl homology domains, it
has been reported that they are active GEFs with distinct substrate specificities toward Rho
family members. Whereas Vav displayed GEF activity for Rac1, Cdc42, RhoA, and RhoG …