PCDH7 Promotes Cell Migration by Regulating Myosin Activity

Cell migration requires spatiotemporally coordinated activities of multicomponent structures including the actomyosin cortex, plasma membrane, adhesion complexes and the polarity proteins. How they function together to drive this complex dynamic process remains an outstanding question. Here, we show that a member of the protocadherin family, PCDH7 displays a polarized localization in migratory cells with a dynamic enrichment at the leading and rear edges. Perturbation of PCDH7 interferes with the migration of nontransformed retinal pigment epithelial cells and invasion of cancer cells. The overexpression of PCDH7 enhances the migration capability of cortical neurons in vivo. PCDH7 interacts with the myosin phosphatase subunits MYPT1 and PP1cβ and it enhances the phosphorylation of regulatory light chain and ERM at the leading and rear edges of migratory cells. The chemical inhibition of phosphatase activity recovers migration phenotypes of PCDH7 knockout cells. We propose that PCDH7 regulate phosphorylation thus activity of myosin and ERM at the polarized cortex by quenching myosin phosphatase that results in a higher persistence of migrating cells. Collectively, our study suggests a new mechanism for the spatial coordination of plasma membrane and the cortex during cell migration.