Microtubule-stabilizing protein that may play an important role during reorganization of microtubules during polarization and differentiation of epithelial cells. Associates with microtubules in a dynamic manner. May play a role in the formation of intercellular contacts. Colocalization with TRPV4 results in the redistribution of TRPV4 toward the membrane and may link cytoskeletal microfilaments. Interacts with TRPV4. Colocalized on microtubules. An intracellular redistribution is triggered during induction of keratinocyte terminal differentiation from microtubules with a perinuclear localization to cortical microtubules organized in spike-like bundles facing intercellular contacts. Expressed in the skin and cells of epithelial origin. Predominantly expressed in the suprabasal layers of the normal epidermis and relatively abundant in squamous cell carcinomas but barely detectable in basal cell carcinomas. Up-regulated upon terminal differentiation of primary keratinocytes. The association with microtubules is regulated by phosphorylation during the cell cycle. During interphase only phosphorylated on serine. Phosphorylated on threonine in mitosis. Belongs to the MAP7 family.