Role of survivin-2B and survivin-ΔEx3 in protecting mitochondrial potential. (A) A549 cells were transfected as shown. Forty-eight hours after transfection, the mitochondria potential was determined using the JC-1 mitochondrial membrane potential detection kit (Cell Technology, MN) following the manufacturer’s recommendations. In healthy cells, the JC-1 dye accumulated in the mitochondria as bright red, but in apoptotic cells the mitochondrial membrane potential collapses, and the JC-1 dye could not accumulate within the mitochondria (no color). Images were captured under a fluorescence microscope (Zeiss LSM510 v2.8) and processed with Photoshop Element Software.