Cytokeratin 14, also known as Keratin 14 and K14, is a member of the keratin family. Cytokeratin 14 is a type I keratin. It is usually found as a heterotetramer with two keratin 5 molecules, a type II keratin. Together they form the cytoskeleton of epithelial cells. Cytokeratin 14 is mainly expressed in the basal layer. It is also strongly expressed in the outer root sheath of anagen follicles. Cytokeratin 14 and keratin 5 may have a role in maintenance of cell proliferation potential in the basal layer of stratified epithelia, modulating phosphatidylinositol 3-kinase/Akt–mediated cell proliferation and/or Notch1-dependent cell differentiation. Cytokeratin 14 defect prevents it from working effectively with keratin 5 and interfering with the assembly of the keratin intermediate filament network. A disruption in this network makes keratinocytes fragile and prone to rupture. Minor trauma to the skin, such as rubbing or scratching, can cause these cells to break down, resulting in the formation of painful, fluid-filled blisters. Mutations in the K14 gene are also responsible for Naegeli-Franceschetti-Jadassohn syndrome and dermatopathia pigmentosa reticularis.
