Required for high-level Shh responses in the developing neural tube. Together with CDK20, controls the structure of the primary cilium by coordinating assembly of the ciliary membrane and axoneme, allowing GLI2 to be properly activated in response to Shh signaling (By similarity). Interacts with CDK20, which promotes CDK20 stability and function (By similarity). Interacts with FAM149B1; may play a role in cilium assembly. May be produced at very low levels due to a premature stop codon in the mRNA, leading to nonsense-mediated mRNA decay. The Rab-GAP TBC domain appears to be inactive, probably due to a lack of the essential Arg and Gln in the catalytic finger motifs. Aberrant splicing. Truncated N-terminus. Wrong choice of CDS.