Diverse function of epiprofin in tooth development

The developing tooth is a good model for studying the mechanism of organogenesis. Tooth development begins as the placode formation with the thickening and invaginating of the oral ectoderm into the dental mesenchyme. A series of reciprocal interactions between these two cell types give rise to differentiation into various cell types including epithelial-derived enamel-secreting ameloblasts and neural crest-derived dentin-secreting odontoblasts. A number of transcription factors control tooth development in order to form unique structures specialized for tooth function with optimized shapes and sizes. We identified Epi-profin (Epfn) as a transcription factor preferentially expressed in teeth. Epfn KO mice display profound embryonic and postnatal growth retardation and develop impaired hair follicle and whisker formation. The drastic phenotypes of Epfn KO are supernumerary tooth formation and lack of enamel in teeth. These observations suggest that Epiprofin plays critical roles in ectodermal organ development and regulates the number of teeth. This review summarizes the roles of Epiprofin in tooth development.