Lundquist, Erik A.Reddien, Peter W.Hartwieg, ErikaHorvitz, H. RobertBargmann, Cornelia I.2007-04-042007-04-042001-11Lundquist, EA; Reddien, PW; Hartwieg, E; Horvitz, HR; Bargmann, CI. Three C-elegans Rac proteins and several alternative Rac regulators control axon guidance, cell migration and apoptotic cell phagocytosis. DEVELOPMENT. NOV 2001. 122(22): 4475-4488.http://dev.biologists.org/https://hdl.handle.net/1808/1264The Caenorhabditis elegans genome contains three rac-like genes, ced-10, mig-2, and rac-2. We report that ced-10, mig-2 and rac-2 act redundantly in axon pathfinding: inactivating one gene had little effect, but inactivating two or more genes perturbed both axon outgrowth and guidance. mig-2 and ced-10 also have redundant functions in some cell migrations. By contrast, ced-10 is uniquely required for cell-corpse phagocytosis, and mig-2 and rac-2 have only subtle roles in this process. Rac activators are also used differentially. The UNC-73 Trio Rac GTP exchange factor affected all Rac pathways in axon pathfinding and cell migration but did not affect cell-corpse phagocytosis. CED-5 DOCK180, which acts with CED-10 Rac in cell-corpse phagocytosis, acted with MIG-2 but not CED-10 in axon pathfinding. Thus, distinct regulatory proteins modulate Rac activation and function in different developmental processes.en-USC. elegansRacced-10mig-2Rac-2Axon pathfindingmigrationPhagocytosisArticleopenAccess