Directed Expression of Keratin 16 to the Progenitor Basal Cells of Transgenic Mouse Skin Delays Skin Maturation

The study investigated the role of keratin 16 (K16) in skin maturation by expressing human K16 cDNA in the basal layer of transgenic mouse skin. Mice with K16 expression showed a postnatal phenotype of hyperkeratotic, scaly skin with reduced fur, thickened epidermis due to basal cell hyperproliferation, and underdeveloped hair follicles. These changes normalized around 5 weeks after birth. The phenotype resembled activated EGF receptor signaling, with increased tyrosine phosphorylation of the EGF receptor observed in newborn skin. The study concluded that K16 expression significantly altered keratinocyte response to signaling, likely due to its unique COOH-terminal tail domain.