MMP-20
MMP-20 (enamelysin) owes its name to its highly specific expression in ameloblasts and dental epithelium, where it is secreted into the developing enamel matrix. Its defining physiological substrates are amelogenin, ameloblastin and enamelin, the protein scaffold that must be precisely cleaved and removed for mineral crystals to mature; this task distinguishes MMP-20 from all other matrixins. Mutations in the MMP20 gene cause autosomal recessive amelogenesis imperfecta, a hereditary defect of enamel formation, demonstrating an essential, nonredundant developmental role. Beyond odontogenesis, low-level expression has been reported in odontogenic tumors, and MMP-20 is a reference enzyme for studies of matrix protein processing during biomineralization.
