Ultrastructural immunolocalization of alpha-keratins and associated beta-proteins (beta-keratins) suggests a new interpretation on the process of hard and soft cornification in turtle epidermis

The epidermis of soft-shelled and hard-shelled turtles has been compared to determine the origin of the different cornification. Immunolocalization of acidic alpha-keratin (AK2) of 45–50 kDa in tonofilaments of the epidermis in Apalone spinifera and absence in the corneous layer where desquamating corneocytes are present supports the biochemical data. Corneocytes shows a weak to absent immunolabeling for beta-proteins (formerly beta-keratins) of...