Regulated expression of the centrosomal protein DdCP224 affects microtubule dynamics and reveals mechanisms for the control of supernumerary centrosome number.

ABSTRACT: The Dictyostelium XMAP215 family member DdCP224 is involved in centrosome duplication and cytokinesis and is concentrated at the centrosome and microtubule tips. Herein, we have created a DdCP224 promoter replacement mutant that allows both over- and underexpression. Overexpression led to supernumerary microtubule-organizing centers and, independently, an increase of the number of multinuclear cells. Electron microscopy demonstrated that supernumerary microtubule-organizing centers represented bona fide centrosomes. Live cell imaging of DdCP224-green fluorescent protein mutants also expressing green fluorescent protein-histone2B as a DNA label revealed that supernumerary centrosomes were also competent of cell cycle-dependent duplication. In contrast, underexpression of DdCP224 inhibited c

SUBMITTER: Graf R 

PROVIDER: S-EPMC207000 | biostudies-literature | 2003 Oct

REPOSITORIES: biostudies-literature