The RIC1-RGP1 complex acts as a guanine nucleotide exchange factor (GEF), which activates RAB6A by exchanging bound GDP for free GTP, and may be thereby required for efficient fusion of endosome-derived vesicles with the Golgi compartment. The RIC1-RGP1 complex participates in the recycling of mannose-6-phosphate receptors (By similarity). It is a regulator of procollagen transport and secretion, and is required for correct cartilage morphogenesis and development of the craniofacial skeleton (PubMed:31932796). Forms a complex with rgp1; the interaction enhances rab6a GTPase activity. ric1-null mutant larvae show micrognathia, small head, shortened trunk, and short, kinked pectoral fins. Craniofacial cartilage elements and newly formed ossification centers are present but they are malformed and smaller than in wild-type controls. Chondrocytes of mutant fishes retain procollagen II intracellularly in large inclusions.