As component of the IFT complex A (IFT-A), a complex required for retrograde ciliary transport and entry into cilia of G protein-coupled receptors (GPCRs), it is involved in cilia function and/or assembly (PubMed:20889716). Essential for functional IFT-A assembly and ciliary entry of GPCRs (PubMed:20889716). Associates with the BBSome complex to mediate ciliary transport (By similarity).