Cathepsin C (CTSC)

Cathepsin C (dipeptidyl peptidase I) is a lysosomal exo-cysteine protease belonging to the peptidase C1 family. Cathepsin C appears to be a central coordinator for activation of many serine proteases in immune/inflammatory cells.Cathepsin C catalyses excision of dipeptides from the N-terminus of protein and peptide substrates, except if (i) the amino group of the N-terminus is blocked, (ii) the site of cleavage is on either side of a proline residue, (iii) the N-terminal residue is lysine or arginine, or (iv) the structure of the peptide or protein prevents further digestion from the N-terminus.Defects in the encoded protein have been shown to be a cause of Papillon-Lefevre disease, an autosomal recessive disorder characterized by palmoplantar keratosis and periodontitis.