Keratin (genitive ') meaning "horn" originating from the Proto-Indo-European "*ḱer-" of the same meaning. It is composed of "horn like", i.e., kerato, to which the chemical suffix -in is appended. The Greek ' is used in many animal names, e.g. "Rhinoceros", meaning "nose with a horn". Keratin filaments are abundant in keratinocytes in the cornified layer of the epidermis; these are proteins which have undergone keratinization. In addition, keratin filaments are present in epithelial cells in general. For example, mouse thymic epithelial cells (TECs) are known to react with antibodies for keratin 5, keratin 8, and keratin 14. These antibodies are
Extracellular matrix exist in varying degrees of stiffness and elasticity, from soft brain tissues to hard bone tissues. The elasticity of the ECM can differ by several orders of magnitude. This property is primarily dependent on collagen and elastin concentration, and it has recently been shown to play an influential role in regulating numerous cell functions. Cells can sense the mechanical properties of their environment by applying forces and measuring the resulting backlash. This plays an important role because it helps regulate many important cellular processes including cellular contraction, cell migration, cell proliferation, differentiation and cell death (apoptosis). Inhibition of nonmuscle myosin