Is a positive regulator of ciliogenesis, playing a crucial role in the initial steps of axoneme extension. It acts as a substrate-adapter for CUL3-RING ubiquitin ligase complexes which mediate the ubiquitination and subsequent proteasomal degradation of TCHP, a protein involved in ciliogenesis down-regulation (PubMed:25270598). May be involved in endoplasmic reticulum calcium ion homeostasis (PubMed:25983243). Homopentamer; forms an closed pentamer (PubMed:28963344). Interacts with CUL3; interaction is direct and forms a 5:5 heterodecamer (PubMed:28963344). Interacts with TCHP (PubMed:25270598). Interacts with CUL3, as part of the BCR(KCTD17) E3 ubiquitin ligase complex, at least composed of CUL3, KCTD17 and RBX1 (PubMed:25270598). Highly expressed in brain. Highest expression is observed in the putamen and the thalamus. The disease is caused by variants affecting the gene represented in this entry. The sequence differs in the N-terminus for unknown reasons.