Regulation of cadherin-mediated cell-cell adhesion by the Rho family GTPases

Reports in the past two years have shown that Cdc42, Rad, and Rho - belongi ng to the Rho small GTPase family - participate in the regulation of cadher in-mediated cell-cell adhesion. IQGAP1, an effector of Cdc42 and Rad, inter acts with cadherin and beta-catenin and induces the dissociation of alpha-c atenin from the cadherin-catenins complex leading to disruption of cell-cel l adhesion: activated Cdc42 and Rad counteract the effect of IQGAP1. Thus, Cdc42 and Rad appear to regulate cadherin-mediated cell-cell adhesion actin g through IQGAP1.