The Rho family of small GTP-binding proteins plays important roles in the regulation of actin
cytoskeleton organization and cell growth. Activation of these GTPases involves the
replacement of bound GDP with GTP, a process catalyzed by the Dbl-like guanine-
nucleotide exchange factors, all of which seem to share a putative catalytic motif termed the
Dbl homology (DH) domain, followed by a pleckstrin homology (PH) domain. Here we have
examined the role of a Dbl-like molecule, the faciogenital dysplasia gene product (FGD1) …