Cathepsin A is an enzyme that is classified both as a cathepsin and a carboxypeptidase. In humans, it is encoded by the CTSA gene. Function 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. Clinical significance Deficiencies in this gene are linked to multiple forms of galactosialidosis. Interactions Cathepsin A has been shown to interact with NEU1. References Further reading External links EC 3.4.16 Proteases Cathepsins