The small GTPases Rab are key regulators of intracellular membrane trafficking, from the formation of transport vesicles to their fusion with membranes. Rabs cycle between an inactive GDP-bound form and an active GTP-bound form that is able to recruit to membranes different set of downstream effectors directly responsible for vesicle formation, movement, tethering and fusion. In its active GTP-bound form, acts redundantly with rab-6.2 (in its active GTP-bound form) to positively regulate the retrograde trafficking of cargo molecules from endosomes to Golgi structures. Required for the retrograde trafficking of glr-1, a subunit of AMPA-type glutamate receptors (AMPRs), out of early endosomes and into the Golgi compartment in neurons. Together with rab-6.2, promotes the retrograde trafficking of mig-14 from endosomes to Golgi structures in the intestine. In oocytes, in its active GTP-bound form, involved in the membrane fusion and exocytosis of secretory vesicles (cortical granules) to play a role in the remodeling of the embryo surface following fertilization. Recruits sep-1 to cortical granules (derived from the Golgi complex) for exocytosis during the oocyte-to-embryo transition. Required for seam cell division and alae formation. Promotes spontaneous reversals in locomotion