Involved in ciliogenesis as part of a complex involved in intraflagellar transport (IFT), the bi-directional movement of particles required for the assembly, maintenance and functioning of primary cilia (PubMed:19253336). Required for the anterograde transport of IFT88 (By similarity). Component of the IFT complex B, at least composed of IFT20, IFT22, HSPB11/IFT25, IFT27, IFT46, IFT52, TRAF3IP1/IFT54, IFT57, IFT74, IFT80, IFT81, and IFT88 (PubMed:19253336). Interacts with IFT88 (PubMed:19253336). Interacts with TTC25 (PubMed:25860617). Interacts with TTC21A (By similarity). Interacts with TTC30A1, TTC30A2, TTC30B and KIF17 (PubMed:23810713). Interacts with USH1G (By similarity). After opioid treatment, expression decreases.