Impact of Amelotin Gene on Barrier Function of Junctional Epithelium

doi:10.13701/j.cnki.kqyxyj.2026.07.004

Abstract

Abstract: Objective: To investigate the impact of amelotin knockout (Amtn^-/-) on the function of the junctional epithelium barrier (JEB). Methods: Mandibular specimens from littermate Amtn^-/- and wild-type (WT) mice were compared. Periodontal tissue morphology and enamel mineralization were analyzed using scanning electron microscopy (SEM), hematoxylin-eosin (HE) staining, immunohistochemistry (IHC), and micro-computed tomography (micro-CT). Results: Three-month-old Amtn^-/- mice exhibited alveolar bone resorption, furcation exposure, disorganized periodontal fibers, junctional epithelium (JE) disintegration with apical migration, and age-dependent exacerbation. One-month-old Amtn^-/- mice showed severe molar enamel wear, residual matrix proteins in ameloblasts, and lack of epithelial coverage in unerupted molars (Amtn^-/- mice). For Amtn^-/- mice, IHC revealed downregulated laminin gamma-2 (LAMC2) expression in the JE basement membrane but upregulated within JE; matrix metalloproteinase-9 (MMP-9) expression was enhanced in both basement membrane and JE interior. Conclusion: Deletion of the Amtn gene can lead to poor enamel mineralization and destruction of JE adhesion, which may be related to the abnormal expression of LAMC2 and MMP-9.

Key words: Amelotin, amelogenesis imperfecta, junctional epithelial barrier, epithelial attachment, periodontal disease

CHU Qing, MU Haiyu, XU Zhenzhen, SUN Yiqun, GAO Yan, GAO Yuguang, XIANG Lili, DONG Zhiheng. Impact of Amelotin Gene on Barrier Function of Junctional Epithelium[J]. Journal of Oral Science Research, 2026, 42(7): 569-574.

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