list of keratins expressed in the human integumentary system list of keratins expressed in the human integumentary system there are many different keratin proteins normally expressed in the human integumentary system. keratin protein expression within the various layers and anatomic locations of the human integumentary system keratin typelocation of expression 1suprabasal epidermis of skin 2 (2e)granular layer 3cornea 4suprabasal epidermis of mucosa 5basal layer 6asuprabasal palmoplantar skin 6bbasal palmoplantar skinnail bedhair follicle 7 8 9suprabasal palmoplantar skin 10suprabasal epidermis 11 12cornea 13suprabasal epidermis of mucosa 14basal layer 15basal layer of mucosa 16suprabasal palmoplantar skin 17basal palmoplantar skin 18 19bulge region of the hair follicle 20merkel cell 21