Component of the BBSome complex (By similarity). The BBSome complex is thought to function as a coat complex required for sorting of specific membrane proteins to the primary cilia (By similarity). The BBSome complex is required for ciliogenesis but is dispensable for centriolar satellite function (By similarity). Required for proper BBSome complex assembly and its ciliary localization (By similarity). Required for cilia biogenesis and both the assembly and movement of intraflagellar transport proteins along the ciliary axoneme (PubMed:15231740, PubMed:17000880, PubMed:22022287, PubMed:22922713, PubMed:26150102). Plays a role in the removal of degraded mechanosensory receptors within the cilia (PubMed:26150102). Plays a role in guanylyl cyclase localization in the ring-like structures at the base of the finger compartment in AFD sensory neurons (PubMed:25335890). In ciliated sensory neurons, required for the sensation of nitric oxide and avoidance of NO-producing organisms like P.aeruginosa (PubMed:30014846). Part of BBSome complex, that contains at least bbs-1, bbs-2, bbs-4, bbs-5, osm-12, bbs-8/ttc-8 and bbs-9 (By similarity). Interacts with bbs-1 (PubMed:22922713). Moves in anterograde and retrograde directions along the ciliary axonemes. Expressed in ciliated cells including amphid and both inner and outer labial neurons of the head and in both phasmid neurons PHA and PHB in the tail at larval stages L1 and L2. Mutants have normal body morphology, but with reduced body length and width, delayed larval development and decreased roaming movements (PubMed:22022287). May exhibit defective chemotaxis tendencies (PubMed:15231740). Defective cilia structure and function (PubMed:15231740, PubMed:22022287, PubMed:26150102). This is characterized by increased accumulation and mislocalization of intraflagellar transport proteins and impaired movement of intraflagellar transport proteins along the ciliary axoneme (PubMed:15231740, PubMed:22922713, PubMed:26150102). Defective polycystin-mediated cilia signaling and mislocalized and increased accumulation of mechanosensory receptors pkd-2, osm-9 and odr-10 within cilia (PubMed:26150102). Impaired localization of the guanylyl cyclase proteins, gcy-8, gcy-18 and gcy-23, within AFD sensory neurons, with accumulation along the dendrite as well as in the finger compartment of AFD neurons (PubMed:25335890).