Required for ventral migration of epidermal cells during ventral enclosure in the embryo and for cell elongation (PubMed:24016757). Also required for ventral migration of P cells during larval development (PubMed:11687661). Involved in asymmetric spindle positioning during anaphase and establishment of cell polarity during embryo development (PubMed:16921365). In adults, involved in regulation of multiple processes including locomotion, pharyngeal pumping, fecundity, ovulation, defecation and body morphology (PubMed:21387015). In body wall muscles, regulates organization of myosin thick filaments downstream of unc-89 (PubMed:18801371). Association with the oxidase bli-3 promotes ROS production and this interaction may be modulated by memo-1, in order to control the oxidative stress response and longevity (PubMed:28085666). GTP hydrolysis is stimulated by unc-89. May interact with unc-89 (via DN and PH domains) (PubMed:18801371). Interacts with bli-3 and memo-1 (PubMed:28085666). Associated with the membrane and the cytoskeleton throughout development (PubMed:7798239). Enriched at the anterior cortex in embryos; localization to the anterior cortex requires kin-18 (PubMed:23064028). In larvae and adults, enriched at the tip of the head where the anterior sensory organ is located and in the pharyngeal nerve ring (at protein level). In embryos, enriched at the boundaries of dorsal cells undergoing intercalation, ventral enclosure and elongation. Highest expression during larval development with a peak at L3 and lower levels in the embryo and adult (at protein level). RNAi-mediated knockdown predominantly results in embryonic arrest with surviving embryos developing elongation-defective uncoordinated kinky larvae (PubMed:24016757, PubMed:11687661). Defective ventral migration of P cells leading to defective gonad development (PubMed:11687661). Defective establishment of anterior-posterior cell polarity in one-cell embryos (PubMed:16921365). Abolished cortical contractility in early embryos (PubMed:23064028). RNAi-mediated knockdown results in disorganized myosin thick filaments in the body wall muscles of the few surviving adults, which is characterized by the formation of abnormal myosin heavy chain myo-3 aggregates, V-shaped crossing of A-bands and areas in which the myosin heavy chain is missing (PubMed:18801371). RNAi-mediated knockdown suppresses reactive oxygen species induction and longevity in the memo-1 mutant (PubMed:28085666). Double RNAi-mediated knockdown with memo-1 eliminates the resistance to oxidative stress in the memo-1 single mutant (PubMed:28085666). Belongs to the small GTPase superfamily. Rho family.