TBCCD1, a new centrosomal protein, is required for centrosome and Golgi apparatus positioning

Abstract

In animal cells the centrosome is actively positioned at the cell center in close association with the nucleus. The mechanisms responsible for this are not completely understood. Here we report the first characterization of human TBCCD1, a protein related to tubulin cofactor C. TBCCD1 localizes at the centrosome and at the spindle midzone, midbody and basal bodies of primary and motile cilia. Knockdown of TBCCD1 in RPE-1 cells caused the dissociation of the centrosome from the nucleus and disorganization of the Golgi apparatus. TBCCD1 depleted cells are larger, less efficient in primary cilia assembly and their migration is slower in wound-healing assays. However, the microtubule nucleating activity of the centrosome is not affected by TBCCD1 silencing. We propose that TBCCD1 is a key regulator of centrosome positioning and consequently of internal cell organization.