Amelotin (AMTN) is a tooth enamel protein which is expressed in maturation-stage ameloblasts and also in the internal basal lamina of junctional epithelium, a unique epithelial structure attached to the tooth surface which protects against the constant microbiological challenge to the periodontium. TNF-α stimulates AMTN gene transcription in human gingival epithelial cells via C/EBP1, C/EBP2, and YY1 elements in the human AMTN gene promoter.AMTN mRNA levels increased at 6 h and reached maximum at 24 h in GE1 cells. Luciferase activities of the mouse AMTN gene promoter constructs were induced by TGFβ1. AMTN mRNA levels were induced at the initiation of apoptosis by TGFβ1, which mediated through the Smad3 bindings to SBEs in the mouse AMTN gene promoter. Amelotin (Amtn) is a recently identified enamel protein secreted by ameloblasts at late stage of enamel development. Runt‑related transcription factor 2 (Runx2) in combination with the coactivator core‑binding factor β (Cbfβ) regulates the early stages of tooth development.