a type II cytoskeletal keratin. The keratins are intermediate filament proteins responsible for the structural integrity of epithelial cells and are subdivided into cytokeratins and hair keratins. Phosphorylation of keratins at specific sites affects their organization, assembly dynamics, and their interaction with signaling molecules. Phsophorylated by p38 kinase, regulating cellular keratin filament reorganization. Phosphorylation on serine residues is enhanced during EGF stimulation and mitosis. Mutation of this protein is a risk factor for cryptogenic liver failure. Note: This description may include information from UniProtKB.