Recruitment and activation of Rac1 by the formation of E-cadherin-mediated cell-cell adhesion sites

摘要: Rac1, a member of the Rho family small GTPases, regulates E-cadherin-mediated cell-cell adhesion. However, it remains to be clarified how localization and activation Rac1 are regulated at sites contact. Here, using enhanced green fluorescence protein (EGFP)-tagged we demonstrate that EGFP-Rac1 is colocalized with E-cadherin contact translocates cytosol during disruption adhesion by Ca(2+) chelation. Re-establishment restoration Ca(2)(+) caused become relocalized, together E-cadherin, Engagement apical membrane anti-E-cadherin antibody (ECCD-2) recruited EGFP-Rac1. We also investigated whether induced measuring amounts GTP-bound based on its specific binding Cdc42/Rac1 interactive region p21-activated kinase. The formation activation. This was inhibited treatment cells neutralizing (DECMA-1) against or wortmannin, an inhibitor phosphatidylinositol 3-kinase (PI 3-kinase). IQGAP1, effector behaved in similar manner confirmed coimmunoprecipitated IQGAP1 establishment Taken together, these results suggest then activated, possibly through PI 3-kinase.