The Process of Cornification Evolved From the Initial Keratinization in the Epidermis and Epidermal Derivatives of Vertebrates: A New Synthesis and the Case of Sauropsids

January 2016 in “ International review of cell and molecular biology ”

Lorenzo Alibardi

cornification keratinization intermediate filament keratins keratin-associated proteins corneous proteins alpha-keratinization beta-keratinization epidermal keratinocytes terminal differentiation

TLDR Cornification evolved from keratinization in vertebrates, with differences between mammals and sauropsids.

The review discussed the evolution of cornification from initial keratinization in vertebrates, highlighting the role of intermediate filament (IF) keratins and their interaction with other proteins, such as keratin-associated proteins (KAPs) and corneous proteins. It emphasized that while alpha-keratinization was prevalent in mammals, beta-keratinization was specific to sauropsids, including reptiles and birds. The study suggested that the process of terminal differentiation in epidermal keratinocytes across vertebrates was a result of these interactions. Future research was recommended to explore the genes and proteins associated with keratin in fish and amphibians to further unify the concept of cornification in vertebrates.

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