Tetratricopeptide Repeat Domain Protein 8 (TTC8)

TTC8 is a tetratricopeptide repeat protein that contains 8 TPR domains and shows similarity to a prokaryotic domain pilF that is involved in pilus formation and twitching mobility. It is mutated in some families with Bardet-Biedl syndrome. In one instance they observed an alignment between 3 consecutive TPRs of BBS4 and a contiguous region of the hypothetical protein TTC8. The authors identified 2 alternatively spliced isoforms. RT-PCR analysis of human tissues detected strong expression in testis, ovary, lung, brain, liver, pancreas, and fetal kidney with lower expression in heart, kidney, placenta, thymus, and spleen. The predicted protein contains 8 C-terminal TPRs and exhibits significant similarity to a prokaryotic domain pilF, involved in twitching mobility and type IV pilus assembly.