Necessary for centrosome duplication at different stages of procentriole formation. Acts as a key negative regulator of ciliogenesis in collaboration with CEP97 by capping the mother centriole thereby preventing cilia formation. Also involved in promoting ciliogenesis. May play a role in the assembly of the mother centriole subdistal appendages thereby effecting the fusion of recycling endosomes to basal bodies during cilia formation. Required for correct spindle formation and has a role in regulating cytokinesis and genome stability via cooperation with CALM1 and CETN2.