Amelx, encoding amelogenin, is a gene of great significance in dental enamel development. Amelogenin makes up about 90% of enamel proteins and is crucial for the normal formation of dental enamel. Mutations in this gene are mainly associated with amelogenesis imperfecta, a group of developmental disorders of dental enamel [1,3,4].

In a study generating Amelx-iCre transgenic mouse lines (a form of conditional knockout mouse model), when bred with Stim1 floxed mice to create ameloblast-specific Stim1 conditional knockout mice (Stim1 cKO), the Stim1 cKO mice showed severely defective enamel phenotypes, including reduced structural integrity, increased attrition, and smaller teeth. This reveals the importance of Amelx-driven ameloblast-specific gene expression in enamel mineralization and ameloblast differentiation [2].

In conclusion, Amelx is essential for dental enamel development. The use of gene-targeted mouse models like Amelx-iCre and associated conditional knockout models has been valuable in understanding its role in amelogenesis imperfecta and the normal process of enamel formation, providing insights into the molecular mechanisms underlying these dental conditions.

References:

1. Tremillo-Maldonado, Omar, Molina-Frechero, Nelly, González-González, Rogelio, Bologna-Molina, Ronell. . [Alteración del gen AMELX en amelogénesis imperfecta. Una breve revisión]. In Gaceta medica de Mexico, 155, 101-107. doi:10.24875/GMM.18003604. https://pubmed.ncbi.nlm.nih.gov/30799455/

2. Said, R, Zheng, L, Saunders, T, Papagerakis, S, Papagerakis, P. . Generation of Amelx-iCre Mice Supports Ameloblast-Specific Role for Stim1. In Journal of dental research, 98, 1002-1010. doi:10.1177/0022034519858976. https://pubmed.ncbi.nlm.nih.gov/31329049/

3. Crawford, Peter J M, Aldred, Michael, Bloch-Zupan, Agnes. 2007. Amelogenesis imperfecta. In Orphanet journal of rare diseases, 2, 17. doi:. https://pubmed.ncbi.nlm.nih.gov/17408482/

4. Martins, Daiana da Silva, Ionta, Franciny Querobim, Pompermaier Garlet, Gustavo, Rios, Daniela, Lussi, Adrian. 2024. Developmental Defects of Enamel. In Monographs in oral science, 32, 10-34. doi:10.1159/000538850. https://pubmed.ncbi.nlm.nih.gov/39321764/