Probable component of the tectonic-like complex (also named MKS complex), a complex localized at the transition zone of primary cilia (PubMed:27577095, PubMed:27646273). Required for ciliary structure and function (PubMed:27577095). Probable component of the tectonic-like complex (also named MKS complex), composed of B9d1, B9d2, Cc2d2a, Mks1 and tctn. Localizes at the transition zone (TZ), a region between the basal body and the ciliary axoneme in the olfactory, auditory and speromatocyte system (PubMed:27646273, PubMed:30013109). In spermatocytes, localizes in the transition zone and the migrating base of the spermatid ciliary cap (PubMed:25447994, PubMed:27646273, PubMed:27577095). Co-localizes with the tectonic-like complex (PubMed:27646273). Expressed in chordotonal neurons in the antennae (at protein level) (PubMed:27646273). Expressed in spermatids (at protein level) (PubMed:27646273, PubMed:25447994, PubMed:27577095). Viable and fertile. Minor defects in sensory cilia function probably due to lack of localization of the tectonic-like module proteins, namely tcnt, B9d1, B9d2 and TMEM216, to the transition zone. Does not affect the recruitment of Cep290 (PubMed:27577095). In sensory cells associated with the notum hair socket, results in structural defects including axonemes with abnormal microtubule connections to the basal body (BB); results in subtle defects in the localization of intraflagellar transport (IFT) proteins and an increase in the ratio of cilium volume to inner membrane volume (PubMed:27577095).