Fig. 4.

Effect of PGC-1α overexpression on HIF-1α stabilization and PHD activity. (A) Immunoblot analysis of HIF-1α in HeLa cells transfected with either PGC-1α expression vector or control vector at either 21% and 10% atmospheric O₂ (Upper) or 21% and 5% atmospheric O₂ (Lower). (B) HeLa cells were exposed to 21% and 5% oxygen with or without PGC-1α overepression and antimycin A (1 μg/mL), and HIF-1α levels were determined by Western blot analysis. (C) Immunoblot analysis of ODD-GFP-V5 expression in HeLa cells transfected with either PGC-1α expression vector or control vector at either 21% or 10% atmospheric O₂. (D) Immunoblot analysis of ODD-GFP-V5 expression in C2C12 cells transfected with either PGC-1α expression vector or control vector in 21% or 10% O₂. n = 3 throughout.