title: Regulation of calbindin-D(28k) expression by Msx2 in the dental epithelium.
abstract: Amelogenesis involves the coordinated expression of a set of molecules that includes enamel matrix proteins and calcium-binding proteins. Msx2 is a member of the divergent homeobox gene family and is instrumental in dental morphogenesis and biomineralization. This study focused on an EF-hand calcium-binding protein, calbindin-D(28k), which is highly expressed in dental epithelium. In vivo data showed that calbindin-D(28k) levels were higher in ameloblasts from Msx2(+/-) mice than Msx2(+/+) mice. Consistent with this finding, calbindin-D(28k) distribution was affected in transgenic mice with ectopic expression in root epithelium in rests of Malassez in Msx2(+/-) and more clearly in Msx2(-/-) mice. In accordance with these in vivo data, calbindin-D(28k) protein and mRNA levels were decreased in LS8 ameloblast-like cells by exogenous Msx2 overexpression. Furthermore, calbindin-D(28k) promoter activity (nt-1075/+34) was specifically diminished in the presence of Msx2 overexpression, showing that Msx2 behave as a transcriptional repressor for calbindin-D(28k) gene expression. In conclusion, Msx2 may control the spatiotemporally restricted frame of calbindin-D(28k) production in the dental epithelium in relation to enamel mineralization, as previously shown for amelogenin.
authors.affiliation: Centre de Recherche des Cordeliers, INSERM UMRS 872, Team 5, Laboratory of Molecular Oral Physiopathology, Paris, France.
authors.forename: Alba
authors.initials: A
authors.lastname: Bolaños
authors.forename: Dominique
authors.initials: D
authors.lastname: Hotton
authors.forename: Didier
authors.initials: D
authors.lastname: Ferbus
authors.forename: Sophia
authors.initials: S
authors.lastname: Loiodice
authors.forename: Ariane
authors.initials: A
authors.lastname: Berdal
authors.forename: Sylvie
authors.initials: S
authors.lastname: Babajko
mesh_terms: D000565:Ameloblasts / Q000166:cytology / Q000378:metabolism; D000818:Animals; D064026:Calbindins; D002460:Cell Line; D004847:Epithelial Cells / Q000378:metabolism*; D055879:Gene Knock-In Techniques; D018398:Homeodomain Proteins / Q000235:genetics; D007150:Immunohistochemistry; D007180:Incisor / Q000378:metabolism; D051379:Mice; D008822:Mice, Transgenic; D009928:Organ Specificity; D011401:Promoter Regions, Genetic; D012333:RNA, Messenger / Q000378:metabolism; D064030:S100 Calcium Binding Protein G / Q000235:genetics / Q000378:metabolism*; D014092:Tooth Root / Q000378:metabolism
chemical_list: D064026:Calbindins; D018398:Homeodomain Proteins; C084119:MSX2 protein; D012333:RNA, Messenger; D064030:S100 Calcium Binding Protein G