Fig. 6.

SMAD3 overexpression increases protein amount and transcriptional activity of FoxO3. A: C2C12 myotubes were infected with increasing dosages of adenovirus encoding SMAD3 (adSMAD3) for 24 h, protein was collected, and Western blotting was performed for total FoxO3 protein. B: FoxO3 mRNA was determined by RT-PCR in adSMAD3-infected C2C12 myotubes. C: HEK293a cells were transfected with plasmid DNA encoding an FRE luciferase reporter, SMAD3, FoxO1, and/or FoxO3. Protein was collected following 48 h of transfection and luciferase activity was measured. *Significantly different from basal (P < 0.05). †Significantly different from FoxO alone (P < 0.05). n = 4 per experiment.