Fig. 1.

Stable β-catenin synergizes with BMP-2 in inducing osteogenesis of C3H10T1/2 cells without affecting cell proliferation. Western analysis of whole cell lysates of C3H10T1/2 cells transduced with a retroviral vector carrying either ΔN151 or LacZ, showing a strong reactive band corresponding to the truncated, ΔN151 β-catenin mutant selectively in virally transduced cells (A, inset). This band matches the specific band detected in the lysate from the packaging cell line, 293GPG cells transfected with a ΔN151 expression construct. Cells transduced with either LacZ or ΔN151 retroviral vectors were cultured for 7 days (A) or 14 days (B) in the absence or in the presence of different concentrations of BMP-2, and alkaline phosphatase activity was determined as a marker of osteogenic commitment. Retrovirally transduced cells were plated onto 96-well dishes at low density and cultured for 48 h before labeling with 5-bromo-2′-deoxy-uridine (BrdU) as an index of cell proliferation (C). *P <0.05 vs. 0; #P <0.05 vs. LacZ (t test for unpaired samples).