title: Osteogenic differentiation of mouse mesenchymal progenitor cell, Kusa-A1 is promoted by mammalian transcriptional repressor Rbpj.
abstract: Pluripotent mesenchymal stem cells possess the ability to differentiate into many cell types, but the precise mechanisms of differentiation are still unclear. Here, we provide evidence that Rbpj (recombination signal-binding protein for immunoglobulin kappa j region) protein, the primary nuclear mediator of Notch, is involved in osteogenesis. Overexpression of Rbpj promoted osteogenic differentiation of mouse Kusa-A1 cells in vitro and in vivo. Transient transfection of an Rbpj expression vector into Kusa-A1 cells upregulated promoter activities of Runx2 and Ose2. Enhanced osteogenic potentials including high alkaline phosphatase activity, rapid calcium deposition, and increased calcified nodule formation, were observed in established stable Rbpj-overexpressing Kusa-A1 (Kusa-A1/Rbpj) cell line. In vivo mineralization by Kusa-A1/Rbpj was promoted compared to that by Kusa-A1 host cells. Histological findings revealed that expression of Rbpj was primarily observed in osteoblasts. These results suggest that Rbpj may play essential roles in osteoblast differentiation.
authors.affiliation: Department of Preventive Dentistry, School of Stomatology, The Fourth Military Medical University, 145 West Changle Road, 710032 Xi'an, PR China.
authors.forename: Shengchao
authors.initials: S
authors.lastname: Wang
authors.forename: Nobuyuki
authors.initials: N
authors.lastname: Kawashima
authors.forename: Kei
authors.initials: K
authors.lastname: Sakamoto
authors.forename: Ken-ichi
authors.initials: K
authors.lastname: Katsube
authors.forename: Akihiro
authors.initials: A
authors.lastname: Umezawa
authors.forename: Hideaki
authors.initials: H
authors.lastname: Suda
mesh_terms: D000818:Animals; D002113:Calcification, Physiologic / Q000235:genetics; D002460:Cell Line; D050659:Core Binding Factor Alpha 1 Subunit / Q000235:genetics; D018507:Gene Expression Regulation, Developmental; D051819:Immunoglobulin J Recombination Signal Sequence-Binding Protein / Q000235:genetics / Q000378:metabolism*; D059630:Mesenchymal Stem Cells / Q000166:cytology*; D051379:Mice; D010012:Osteogenesis / Q000235:genetics*; D039904:Pluripotent Stem Cells / Q000166:cytology* / Q000378:metabolism; D011401:Promoter Regions, Genetic; D051880:Receptors, Notch / Q000235:genetics
chemical_list: D050659:Core Binding Factor Alpha 1 Subunit; D051819:Immunoglobulin J Recombination Signal Sequence-Binding Protein; C497571:Rbpj protein, mouse; D051880:Receptors, Notch; C493716:Runx2 protein, mouse