Fig. 7.

Model for PTP-PEST regulation of colon carcinoma motility. PTP-PEST expression controls epithelial morphology in KM12C colon carcinoma cells. Through its localization in adherens junctions, PTP-PEST restricts epithelial cell motility. PTP-PEST controls the activity of Rac1 and RhoA at sites of cadherin engagement to promote junctional assembly and stability. In the absence of PTP-PEST, Rac1 and RhoA activity are misregulated, adherens junctions are impaired, and the cells acquire a highly motile and mesenchymal phenotype.