AGBL5 and Hydrocephalus: In zebrafish, which express four ccp genes (i.e., ccp1, ccp2, ccp5, and ccp6), only ccp5 deficiency leads to cilia MT hyperglutamylation and motility defects that induce a typical spectrum of ciliopathy phenotypes (e.g., axis curvature, pronephric cysts, and hydrocephalus)20.