Small Guanosine Triphospatase RhoA and Rho-Associated Kinase as Regulators of Trophoblast Migration

The small guanosine triphosphatase Rho controls cell adhesion and motility through reorganization of the actin cyto-skeleton and regulation of actomyosin contractility. Among the putative target molecules of Rho, a Rho-associated coiled coil-forming protein kinase (ROCK) is thought to participate in Rho-mediated cell adhesion and motility. In the present study, we explored the expression and function of RhoA and ROCK in human trophoblast cells. The colocalization of RhoA, cytokeratin 8/18, and cytokeratin 7 in some cells located in the decidual stromal region indicated that extravillous trophoblast cells expressed RhoA. In double staining for RhoA and ROCK in human chorionic villi, RhoA staining was strongly positive in the cytoplasm of cytotrophoblasts, whereas ROCK stained in the cytoplasm of cytotrophoblasts and syncytiotrophoblasts. Both RhoA and ROCK were stained in cytoplasma of cultured human cytotrophoblast. Cultured human trophoblast cells contained actin stress fibers that were lost after treatm...