UC Merced

RhoU and RhoV are Rho GTPases a part of the Ras superfamily and are atypical due to fast-cycling of GTP/GDP, making them constitutively active. Their unique N and C terminals regulate their submembrane localization for cellular activity. This, along with their fast-cycling nature categorizes them into their own subfamily. Rho GTPases are well known for their regulation of cell migration, polarity, apoptosis, proliferation and many other processes through effector protein interaction and behave in a switch-like mechanism. Over the last 20 years, studies have been connecting RhoV and RhoU to regulating the cytoskeleton due to their involvement with adhesion protein localization and induction of migratory protrusions. Our lab has found that the Rho GTPase RhoV is dynamically expressed in the zebrafish endoderm; rhov expression is high during gastrulation and low during mesenchymal to epithelial transition (MET). The endoderm is an essential germ layer that will form the epithelial layer of organs such as the respiratory tract, gut, and intestines. How MET is triggered in endodermal cells is still unknown. RhoV is a Rho GTPase whose role has not been investigated within the endodermal cell migration to sheet formation. Here, we used CRISPR-generated RhoV mutants and rhov overexpression to investigate the role of RhoV in the mesenchymal to epithelial transition in zebrafish endoderm. This work, in addition to past studies investigating RhoU and RhoV in development provides compelling reasoning into how RhoU and RhoV may be regulating endodermal cell migration in zebrafish.