Keratin is a family of tough structural proteins found in cells of the skin, hair, nails, and other epithelial structures.
Keratins provide mechanical strength and help cells withstand physical stress. In the epidermis, keratin is produced in large amounts as keratinocytes mature toward the skin surface.
Different keratin proteins are expressed in different tissues and at different stages of cell development.
QUICK FACT
Keratin is a protein, whereas keratinization is the biological process by which certain epithelial cells become specialized and accumulate keratin.
COMMONLY CONFUSED WITH
- Collagen: another structural protein, particularly abundant in connective tissues.
- Keratinocyte: the cell that produces keratin and forms most of the epidermis.
SEE ALSO