Control of epidermal and hair root protein synthesis

Within the past several years, studies of protein synthesis in a variety of systems have focused upon translational control and post-translational modification. In parallel, the specific studies of keratin biosynthesis in tissues of epithelial origin have been directed at these same areas. Multiple proteins which effect positive and negative control over formation of the 80S initiation complex have been identified in mammalian epidermis. The current status of studies of these proteins is reviewed in this presentation. In addition, we discuss our studies of epidermal messenger RNA. The mRNA for keratin has been identified in tissue of avian origin and, more recently, mRNA has been isolated and partially purified from guinea pig epidermis. The messenger has a poly A-rich region and a sedimentation coefficient of approximately 18S. It codes for keratins in heterologous cell-free systems.