FIGURE 1.

Expression profiles of the ERRγ in osteoblast progenitor cells. A, expression of ERRγ mRNA in osteoblast progenitor cells. Primary osteoblasts, MC3T3-E1, and C2C12 cells were cultured in the absence or presence of BMP2 (200 ng/ml) for 24 h. RT-PCR was carried out with the indicated primers. B, expression of ERRγ during osteoblast differentiation by BMP2. C2C12 cells were cultured in osteogenic medium containing ascorbic acid (50 μg/ml) and β-glycerophosphate (5 mm) in the presence of BMP2 (200 ng/ml) for 5 days. At the designated time points, cells were harvested for total RNA isolation, and RT-PCR was performed with the indicated primers. C and D, Western blot analysis of ERRγ expression. Primary osteoblasts and C2C12 cells were cultured in osteogenic medium with BMP2 for 5 days. At the indicated time points, the protein extracts were used for Western blot analysis with the indicated antibody. E and F, transactivation of ERRγ promoter by BMP2. C2C12 and MC3T3-E1 cells were transfected with 200 ng of ERRγ-Luc reporter plasmid and 100 ng of pCMV-β-galactosidase as an internal control with the indicated amounts of BMP2, respectively. Data are expressed as the mean ± S.D. of three independent experiments.