Cilium-specific protein required for the stability of the ciliary architecture. Involved in regulation of microtubule-based cilia and actin-based brush border microvilli (Probable). Specifically expressed in all ciliated tissues. Expressed in ciliated tissues throughout development. At gastrula stages, it is highly expressed in dorsal forerunner cells, which aggregate to form the ciliated Kupffer's vesicle. At the 12-somite stage (14 hpf), expression is restricted to the otic placode, pronephric duct primordia and floorplate. At 20 hpf, it is expressed in the pronephric duct, neural tube, nose and diffusely in the brain. Expression becomes restricted to the nose and lateral line organs at 72 hpf. Development of pronephric cysts followed by death during early larval stages, at approximately 8 dpf, as a result of severe edema that is likely to be a consequence of pronephric disease progression. Fishes develop pronephric cysts with an increased proliferative index, severely reduced brush border, and disorganized pronephric cilia manifesting impaired localized fluid flow consistent with ciliary dysfunction. Electron microscopy analysis reveal ultrastructural irregularities of the dynein arms and misalignments of the outer-doublet microtubules on the ciliary axonemes. Belongs to the DNAAF1 family.