Involved in the cornified cell envelope formation. Multifunctional epidermal matrix protein. Reversibly binds calcium. Expression is scattered in the normal epidermis but strong in the acrosyringium, the inner hair root sheath and in the filiform papilli of the tongue. Can be divided into a N-terminal domain with significant homology to S100-like calcium-binding proteins, a central domain containing a series of short tandem repeats, and two flanking segments with low homology to the consensus sequences of the central repeats. Potential substrate of transglutaminase. Some arginines are probably converted to citrullines by peptidylarginine deimidase. Belongs to the S100-fused protein family.