Involved in the mineralization and structural organization of enamel. Involved in the extension of enamel during the secretory stage of dental enamel formation. Expressed by secretory-phase ameloblasts. Intact enamelin and large-molecular-weight enamelins are limited to the most superficial layer of the developing enamel matrix, while low-molecular-weight enamelins are observed in deeper enamelin. Preferential localization among the crystallites in rod and interrod enamel. Expressed from late differentiation to the transition stage. Proteolytically cleaved into several smaller polypeptides. Cleavage of N-terminal region of enamelin occurs soon after secretion. Phosphorylated by FAM20C in vitro.