Cathepsin A is an enzyme that is classified both as a cathepsin and a carboxypeptidase. In humans, it is encoded by the CTSA gene.[5]
This gene encodes a glycoprotein that associates with lysosomal enzymes beta-galactosidase and neuraminidase to form a complex of high-molecular-weight multimers. The formation of this complex provides a protective role for stability and activity. It is protective for β-galactosidase and neuraminidase.[6]
Deficiencies in this gene are linked to multiple forms of galactosialidosis.[5]