As a 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 ciliogenesis and ciliary protein trafficking (PubMed:21473986, PubMed:28400947, PubMed:29220510). May promote CASP3 activation and TNF-stimulated apoptosis.