Keratin 72 (KRT72)

The 524-amino acid mouse protein has a calculated molecular mass of about 57.3 kD. Mouse and human K6IRS2 share 70% amino acid identity, including 84% identity in the rod domain. Most of the interspecies differences are in the V1 and V2 domains. Immunohistochemical analysis of mouse tissues showed that K6irs2 is completely specific for the epithelial cells of the inner root sheath of anagen hair follicles. There appeared to be a sharp demarcation where expression ended, which was below the region where the sebaceous gland joins the follicle. The inner root sheath of vibrissae was also positive for mouse K6irs2. Expression was not detected in the foot pad, in interfollicular epidermis, in any epithelia of internal organs, mucosal tissues, sebaceous glands, or eccrine sweat glands, or in epithelial structures of the tongue.