Degrades amelogenin, the major protein component of the enamel matrix and two of the macromolecules characterizing the cartilage extracellular matrix: aggrecan and the cartilage oligomeric matrix protein (COMP). May play a central role in tooth enamel formation. Cleaves aggrecan at the '360-Asn-|-Phe-361' site. Binds 2 Zn(2+) ions per subunit. Binds 2 calcium ions per subunit. Expressed specifically in the enamel organ. Expression initiates prior to the onset of dentin mineralization and continues throughout the secretory stage of amelogenesis. The conserved cysteine present in the cysteine-switch motif binds the catalytic zinc ion, thus inhibiting the enzyme. The dissociation of the cysteine from the zinc ion upon the activation-peptide release activates the enzyme. Autoactivates at least at the 107-Asn-|-Tyr-108 site. The disease is caused by variants affecting the gene represented in this entry. Belongs to the peptidase M10A family.