Int J Biol Sci 2017; 13(8):1082-1091. doi:10.7150/ijbs.20905
Spatiotemporal Expression of Wnt/β-catenin Signaling during Morphogenesis and Odontogenesis of Deciduous Molar in Miniature Pig
1. Molecular Laboratory for Gene Therapy and Tooth Regeneration, Beijing Key Laboratory of Tooth Regeneration and Function Reconstruction, Capital Medical University School of Stomatology, Beijing, China;
2. Department of Oral and Maxillofacial Surgery, Xiangya Hospital, Central South University, Changsha, China;
3. Department of Oral Basic Science, School of Stomatology, Dalian Medical University, Dalian, China;
4. Department of Biochemistry and Molecular Biology, Capital Medical University School of Basic Medical Sciences, Beijing, China.
Xiaoshan Wu and Yan Li contributed equally to this work.
The canonical Wnt/β-catenin signaling pathway has been shown to play essential roles in tooth initiation and early tooth development. However, the role of Wnt/β-catenin signaling in cusp patterning and crown calcification in large mammals are largely unknown. In our previous study, miniature pigs were used as the animal model due to the similarity of tooth anatomy and replacement pattern between miniature pig and human. Dynamic gene expression of third deciduous molar (DM3) in miniature pig at early stages was profiled using microarray method and expression of Wnt genes was significantly correlate with odontogenesis. In the present study, dynamic expression patterns of Wnt/β-catenin signaling genes of DM3 at cap, early bell and late bell (secretory) stage were identified. We found that Lef1 and Axin2 were expressed in the enamel knot and underlying mesenchyme regions. Meanwhile, Dkk1 was expressed in the peripheral and lower parts of dental papilla, thus forming the potential Wnt signaling gradient. We also found that β-Catenin, Axin2 and Lef1 were expressed strongly in undifferentiated cells of the inner enamel epithelium (IEE), but weakly in differentiated ameloblasts. Furthermore, we found that both Wnt signaling read-out gene Lef1 and the inhibitor Dkk1 were co-expressed in the pre-odontoblasts. In conclusion, the spatiotemporal distribution and potential gradient of Wnt signaling may contribute to cusp patterning and crown calcification. These data may yield insight into future study of precise control of crown morphogenesis and regeneration in large mammals.
Keywords: Wnt signaling, tooth, development, miniature pig
Wu X, Li Y, Wang F, Hu L, Li Y, Wang J, Zhang C, Wang S. Spatiotemporal Expression of Wnt/β-catenin Signaling during Morphogenesis and Odontogenesis of Deciduous Molar in Miniature Pig. Int J Biol Sci 2017; 13(8):1082-1091. doi:10.7150/ijbs.20905. Available from http://www.ijbs.com/v13p1082.htm