Component of the DZIP1-Fam92-Cby complex which promotes ciliogenesis in sensory neurons and spermatocytes by acting downstream of Cep290 to initiate early ciliary membrane formation and thus transition zone (TZ) assembly (PubMed:31821146). During spermatogenesis, also regulates distal elongation of the basal-body and their docking (anchoring) to the plasma membrane and as a consequence, regulates the initiation and proper elongation of axonemal microtubules (PubMed:31821146). Within the complex, required to recruit or stabilize Cby at the distal basal body of cilia to promote DZIP1-mediated early ciliary membrane formation and initiate TZ assembly (PubMed:31821146, PubMed:33370260). May also act with Dzip1 to restrict cep290 localization to the proximal part of the TZ (PubMed:31821146). May also be involved in recruitment or stabilization of Mks1 at the TZ (PubMed:31821146). Component of a ciliary transition zone (TZ)-localized complex composed of DZIP1, Fam92 and Cby (PubMed:31821146). Interacts directly with Cby (PubMed:31821146). Localizes at the transition zone (TZ) in type I sensory neurons and spermatocytes (PubMed:31821146). Localizes at the centriolar distal ends of early spermatocytes and in elongating spermatids, when the TZ migrates away from the basal body, localizes at the ring centriole (PubMed:31821146). In neurons of the second and third antennal segments, expressed at the tip of the dendrites. Viable but displays adherent transition zone (TZ) assembly in sensory neurons and spermatocytes (PubMed:31821146). Consequently, adults display phenotypes associated with ciliary dysfunction and disorganization, such as reduced geotaxis response and decreased male fertility (PubMed:31821146). Some mutants also display, reduced scolopidia cilia number, deformed axonemes, excess accumulation of material beneath the ciliary membrane and deformation of the ciliary membrane (PubMed:31821146). In spermatocytes, some centrioles are undocked and display irregular distal ends or microtubules extending from the distal ends (PubMed:31821146). Dzip expression is slightly reduced and in spermatocytes, Mks1 is lost or reduced at the cilliary transition zone and Cby is completely lost at the tip of the centrioles (PubMed:31821146). Belongs to the CIBAR family.