Cep44 functions in centrosome cohesion by stabilizing rootletin

Abstract

The centrosome linker serves to hold the duplicated centrosomes together until they separate in late G2/mitosis. Precisely how the linker is assembled remains an open question. In this study, we identify Cep44 as a novel component of the linker. Cep44 localizes to the proximal end of centrioles, including mother and daughter centrioles, and its ablation leads to loss of centrosome cohesion. Cep44 does not impinge on the stability of C-Nap1, LRRC45 or Cep215, and vice versa, and these proteins are independently recruited to the centrosome. Rather, Cep44 associates with rootletin and regulates its stability and localization to the centrosome. Our findings reveal a role of a previously uncharacterized protein Cep44 for centrosome cohesion and linker assembly.