Osteogenic differentiation of mouse mesenchymal progenitor cell, Kusa-A1 is promoted by mammalian transcriptional repressor Rbpj.
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.
Wang
Shengchao
S
Department of Preventive Dentistry, School of Stomatology, The Fourth Military Medical University, 145 West Changle Road, 710032 Xi'an, PR China.
Kawashima
Nobuyuki
N
Sakamoto
Kei
K
Katsube
Ken-ichi
K
Umezawa
Akihiro
A
Suda
Hideaki
H
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
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