Gene

Cell biology

Cilium

Biology

Cell cycle

Regulator

Basal body

Phosphorylation

Centrosome

Microtubule

Ciliogenesis

Phosphoprotein

Centriole

Genetics

Flagellum

Cell

Kinesin

Nature Communications

The primary cilium is elongated from the mother centriole and has diverse signaling roles during development and disease. The CP110-CEP97 complex functions as a negative regulator of ciliogenesis, although the mechanisms regulating its mother centriole localization are poorly understood. Here we show that M-Phase Phosphoprotein 9 (MPP9) is recruited by Kinesin Family Member 24 (KIF24) to the distal end of mother centriole where it forms a ring-like structure and recruits CP110-CEP97 by directly binding CEP97. Loss of MPP9 causes abnormal primary cilia formation in growing cells and mouse kidneys. After phosphorylation by Tau Tubulin Kinase 2 (TTBK2) at the beginning of ciliogenesis, MPP9 is targeted for degradation via the ubiquitin-proteasome system, which facilitates the removal of CP110 and CEP97 from the distal end of the mother centriole. Thus, MPP9 acts as a regulator of ciliogenesis by regulating the localization of CP110-CEP97 at the mother centriole.

M-Phase Phosphoprotein 9 regulates ciliogenesis by modulating CP110-CEP97 complex localization at the mother centriole