title: Bmp2 deletion causes an amelogenesis imperfecta phenotype via regulating enamel gene expression.
abstract: Although Bmp2 is essential for tooth formation, the role of Bmp2 during enamel formation remains unknown in vivo. In this study, the role of Bmp2 in regulation of enamel formation was investigated by the Bmp2 conditional knock out (Bmp2 cKO) mice. Teeth of Bmp2 cKO mice displayed severe and profound phenotypes with asymmetric and misshaped incisors as well as abrasion of incisors and molars. Scanning electron microscopy analysis showed that the enamel layer was hypoplastic and enamel lacked a typical prismatic pattern. Teeth from null mice were much more brittle as tested by shear and compressive moduli. Expression of enamel matrix protein genes, amelogenin, enamelin, and enamel-processing proteases, Mmp-20 and Klk4 was reduced in the Bmp2 cKO teeth as reflected in a reduced enamel formation. Exogenous Bmp2 up-regulated those gene expressions in mouse enamel organ epithelial cells. This result for the first time indicates Bmp2 signaling is essential for proper enamel development and mineralization in vivo.
authors.affiliation: Department of Stomatology, Xiangya Hospital, Central South University, Changsha, China; Department of Developmental Dentistry, The University of Texas Health Science Center at San Antonio, Floyd Curl Drive, San Antonio, Texas.
authors.forename: Feng
authors.initials: F
authors.lastname: Guo
authors.forename: Junsheng
authors.initials: J
authors.lastname: Feng
authors.forename: Feng
authors.initials: F
authors.lastname: Wang
authors.forename: Wentong
authors.initials: W
authors.lastname: Li
authors.forename: Qingping
authors.initials: Q
authors.lastname: Gao
authors.forename: Zhuo
authors.initials: Z
authors.lastname: Chen
authors.forename: Lisa
authors.initials: L
authors.lastname: Shoff
authors.forename: Kevin J
authors.initials: KJ
authors.lastname: Donly
authors.forename: Jelica
authors.initials: J
authors.lastname: Gluhak-Heinrich
authors.forename: Yong Hee Patricia
authors.initials: YH
authors.lastname: Chun
authors.forename: Stephen E
authors.initials: SE
authors.lastname: Harris
authors.forename: Mary
authors.initials: M
authors.lastname: MacDougall
authors.forename: Shuo
authors.initials: S
authors.lastname: Chen
mesh_terms: D000566:Amelogenesis / Q000235:genetics*; D000567:Amelogenesis Imperfecta / Q000235:genetics / Q000378:metabolism; D000818:Animals; D015153:Blotting, Western; D055396:Bone Morphogenetic Protein 2 / Q000235:genetics*; D003743:Dental Enamel / Q000196:embryology*; D004195:Disease Models, Animal; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D051379:Mice; D018345:Mice, Knockout; D008855:Microscopy, Electron, Scanning; D010641:Phenotype; D060888:Real-Time Polymerase Chain Reaction; D014070:Tooth / Q000196:embryology* / Q000473:pathology; D055114:X-Ray Microtomography
chemical_list: C525719:Bmp2 protein, mouse; D055396:Bone Morphogenetic Protein 2