Plasma membrane-associated small GTPase specifically involved in angiogenesis (PubMed:21628409, PubMed:24434213, PubMed:30158707). Required for endothelial cell migration during vascular development via its interaction with GLUL (PubMed:30158707). Elicits the formation of F-actin-rich structures, thereby regulating endothelial cell migration (PubMed:30158707).