Component of the epidermal cornified cell envelopes. Found in keratohyalin granules in the granular cells of the epidermis. Expressed in cornified epidermis, psoriatic and regenerating skin after wounding. Found in the upper granular layer and in the entire cornified layer of epidermis. By UV-B irradiation. Processed during the process of epidermal differentiation. Forms covalent cross-links mediated by transglutaminase TGM3, between glutamine and the epsilon-amino group of lysine residues (in vitro). Belongs to the S100-fused protein family. In the N-terminal section; belongs to the S-100 family.