Skin care by keratins

摘要

Keratin proteins perform several functions in skin cells, including those of providing mechanical support and protection against injury. But it seems they also have a more active part to play in healing wounds. Like the musculoskeletal framework of humans or the steel-girder scaffolds of buildings, the intermediate filaments of the cytoskeleton shield cells from mechanical forms of injury. Intermediate filaments are made up of a large family of tissue-specific proteins, including desmin in muscle, neuro-filaments in neurons and keratins in the epithelial cells that line organs such as the skin. Although intermediate filaments are well known for their protective properties, it seems that they may also have a role in damage repair. On page 362 of this issue, Kim et al. provide a direct mechanistic link between an increase in the expression of the gene for keratin K17 and the characteristic increase in protein synthesis and cell growth seen in the cells around wounds.