Vimentin impacts centrosome function and microtubule acetylation.

Cell polarity is important for controlling cell shape, motility, and cell division processes. Vimentin intermediate filaments are necessary for proper polarization of migrating fibroblasts and assembly of vimentin and microtubule networks is dynamically coordinated, but the precise details of how vimentin mediates cell polarity remain unclear. Here, we characterize the effects of vimentin on the structure and microtubule-nucleating activity of the cell centrosome and the dynamics of the microtubule network in wild-type and vimentin-null mouse embryonic fibroblasts (mEF’s). We find that vimentin mediates the structure of the pericentrosomal material, promotes centrosomemediated microtubule regrowth, and increases the level of stable acetylated microtubules in the cell. Our results suggest that vimentin modulates centrosome structure and function as well as microtubule network stability, which has important implications for how cells establish proper cell polarization and persistent migration.