Cilium-specific protein required to control the microtubule-based, ciliary axoneme structure. Required for normal sensory cilium function. May act by maintaining the association between IFT subcomplexes A and B. Monomer. Associates to the cilium membrane via palmitoylation. Localizes to proximal ciliary membranes, to an inversin-like subciliary membrane compartment, excluding the transition zone. Specifically expressed in ciliated sensory neurons throughout development in both hermaphrodites. The RVVP region and palmitoylation sites are required for compartmentalization inside cilium to prevent distal cilium and nuclear targeting. Sumoylation regulates the targeting of membrane sensory receptors to the cilium. Shortened cilia with various ultrastructural deformities and a disrupted association between IFT subcomplexes A and B. Belongs to the small GTPase superfamily. Arf family.