Impaired osteoblastic differentiation, reduced bone formation, and severe osteoporosis in noggin-overexpressing mice
J. Clin. Invest. Xue-Bin Wu, et al. 112:924 doi:10.1172/JCI15543 [Go to this article.]

Figure 5
Effects of overexpression of noggin in U-33 cells. Overexpression of noggin in U-33 cells generated by a virus infection system (see Methods) was detected by Western blotting (a) and immunocytostaining (b) using an anti-noggin monoclonal antibody. Cells infected with empty viral vector (Vector) were used as control. Arrow indicates 30 kDa protein under reducing conditions (a). Expression of Runx-2, bone sialoprotein (BSP), and osteocalcin (c), osteoclast-supporting activity (d), and expression of RANK-L in the presence of 10^–8 M 1,25(OH)₂D₃ (e) were compared in the control and noggin-infected U-33 cells. The expression levels of Runx-2, BSP, osteocalcin, and RANK-L were measured by real-time PCR and expressed as a ratio to untreated control (Vector) cells. TRAP-positive osteoclast number and RANK-L expression are expressed as mean ± SEM. *P < 0.05, significantly different from untreated control cells.