title: Sox2 marks epithelial competence to generate teeth in mammals and reptiles.
abstract: Tooth renewal is initiated from epithelium associated with existing teeth. The development of new teeth requires dental epithelial cells that have competence for tooth formation, but specific marker genes for these cells have not been identified. Here, we analyzed expression patterns of the transcription factor Sox2 in two different modes of successional tooth formation: tooth replacement and serial addition of primary teeth. We observed specific Sox2 expression in the dental lamina that gives rise to successional teeth in mammals with one round of tooth replacement as well as in reptiles with continuous tooth replacement. Sox2 was also expressed in the dental lamina during serial addition of mammalian molars, and genetic lineage tracing indicated that Sox2(+) cells of the first molar give rise to the epithelial cell lineages of the second and third molars. Moreover, conditional deletion of Sox2 resulted in hyperplastic epithelium in the forming posterior molars. Our results indicate that the Sox2(+) dental epithelium has competence for successional tooth formation and that Sox2 regulates the progenitor state of dental epithelial cells. The findings imply that the function of Sox2 has been conserved during evolution and that tooth replacement and serial addition of primary teeth represent variations of the same developmental process. The expression patterns of Sox2 support the hypothesis that dormant capacity for continuous tooth renewal exists in mammals.
authors: Institute of Biotechnology, Developmental Biology Program, University of Helsinki, 00014 Helsinki, Finland.
authors: Emma
authors: E
authors: Juuri
authors: Maria
authors: M
authors: Jussila
authors: Kerstin
authors: K
authors: Seidel
authors: Scott
authors: S
authors: Holmes
authors: Ping
authors: P
authors: Wu
authors: Joy
authors: J
authors: Richman
authors: Kristiina
authors: K
authors: Heikinheimo
authors: Cheng-Ming
authors: CM
authors: Chuong
authors: Katrin
authors: K
authors: Arnold
authors: Konrad
authors: K
authors: Hochedlinger
authors: Ophir
authors: O
authors: Klein
authors: Frederic
authors: F
authors: Michon
authors: Irma
authors: I
authors: Thesleff
mesh_terms: D000818:Animals; D015415:Biomarkers / Q000378:metabolism; D002478:Cells, Cultured; D004622:Embryo, Mammalian; D004847:Epithelial Cells / Q000378:metabolism*; D005260:Female; D005289:Ferrets; D006801:Humans; D008322:Mammals / Q000196:embryology / Q000235:genetics / Q000254:growth & development; D051379:Mice; D008822:Mice, Transgenic; D008954:Models, Biological; D011247:Pregnancy; D012038:Regeneration / Q000235:genetics / Q000502:physiology; D012104:Reptiles / Q000235:genetics / Q000254:growth & development; D055748:SOXB1 Transcription Factors / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D014070:Tooth / Q000196:embryology / Q000254:growth & development* / Q000378:metabolism / Q000502:physiology
chemical_list: D015415:Biomarkers; D055748:SOXB1 Transcription Factors