Constitutive activation of β-catenin in ameloblasts leads to incisor enamel hypomineralization
Enamel is the hardest tissue with the highest degree of mineralization protecting the dental pulp from injury in vertebrates. The ameloblasts differentiated from ectoderm-derived epithelial cells are a single cell layer and are important for the enamel formation and mineralization. Wnt/β-catenin signaling has been proven to exert an important role in the mineralization of bone, dentin and cementum. Little was known about the regulatory mechanism of Wnt/β-catenin signaling pathway in ameloblasts during amelogenesis, especially in the mineralization of enamel. To investigate the role of β-catenin in ameloblasts, we established Amelx-Cre; β-catenin∆ex3fl/fl (CA-β-catenin) mice, which could constitutive activate β-catenin in ameloblasts. It showed the delayed mineralization and eventual hypomineralization in the incisor enamel of CA-β-catenin mice. Meanwhile, the amelogenesis-related proteinases Mmp20 and Klk4 were decreased in the incisors of CA-β-catenin mice. These data indicated that β-catenin plays an essential role in differentiation and function of ameloblasts during amelogenesis.
Keywordsβ-Catenin Ameloblast Enamel Hypomineralization
This work was supported by grants from the National Natural Science Foundation of China (Grant Nos: 81570966, 81371141), the Specialized Research Fund for the Doctoral Program of Higher Education (Grant No: 20130072110020) and the Fundamental Research Funds for the Central Universities.
Linlin Fan, Yuguang Gao, Chun-Hung Chu and Qi Zhang contributed to conception, design, data acquisition analysis and interpretation, drafted and critically revised the manuscript; Shijian Deng, Xin Sui, Mengmeng Liu, Shuhua Cheng, Yunfei Wang contributed to conception, design and data acquisition.
Compliance with ethical standards
Conflict of interest
No potential conflicts of interest are disclosed.
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