Figure 4. PGE2 suppresses BMP reporter activation and stimulates TGF-β reporter activation.

Twenty-four hours after plating, C5.18 cells were co-transfected with 1μg of 12XSBE-luc in the presence of 0.1 μg SV40 renilla luciferase (A). After an additional twenty-four hours, cells were treated with 100 ng/ml BMP-2 or control medium in the presence or absence of 1 μM PGE2 or 0.5 mM db-cAMP. Forty-eight hours post-transfection, luciferase activity was measured. (B) Twenty-four hours after plating, C5.18 cells were co-transfected with 1μg of 4XSBE-luc in the presence of 0.1 μg SV40 renilla luciferase. After an additional 24 hours, the cells were treated with 5 ng/ml TGF-β or control medium in the presence or absence of both PGE2 (1 μM) or BMP-2 (100ng/ml). The experiments were done in triplicate, and values were normalized using SV40 renilla luciferase activity. Asterisk denotes significance at a level of p≤0.05 with comparisons made to the control value or to data points indicated by the bars.