TTBK2
Dominant truncating mutations in TTBK2 cause spinocerebellar ataxia type 11, a slowly progressive cerebellar degeneration, making TTBK2 one of the few CK1-group kinases with a clear Mendelian disease. The enzyme is essential for ciliogenesis: it localizes to the basal body and removes the capping protein CP110 so that the axoneme can elongate, and Ttbk2-null mice die with severe patterning defects. TTBK2 also phosphorylates tau in vitro and has been linked to primary ciliary signaling. Unlike TTBK1, whose proline-rich tail dominates its regulation, TTBK2 function is disrupted when its autoinhibitory C-terminus is lost.
