Involved in membrane trafficking between the Golgi complex and endosomes during early embryonic development. Regulates the Golgi to endosome transport of FGFR-containing vesicles during early development, a key process for developing basement membrane and epiblast and primitive endoderm lineages during early postimplantation development. May act by modulating the kinesin KIF16B-cargo association to endosomes. Regulates, together with its guanine nucleotide exchange factor DENND6A, the specific endocytic transport of ADAM10, N-cadherin/CDH2 shedding and cell-cell adhesion (By similarity). Interacts with KIF16B. Interacts with ZFYVE20 (By similarity). Recruited to recycling endosomes by DENND6A. Recruited to phagosomes containing S.aureus or M.tuberculosis. Belongs to the small GTPase superfamily. Rab family.