Predicted to enable phosphatidylinositol-3-phosphate binding activity. Involved in cilium assembly. Predicted to be part of BBSome. Predicted to be active in ciliary basal body. Is expressed in chordotonal neurons; eo neurons; and larval antenno-maxillary sensory complex. Human ortholog(s) of this gene implicated in Bardet-Biedl syndrome and Bardet-Biedl syndrome 5. Orthologous to human BBS5 (Bardet-Biedl syndrome 5).