Fig. 5. Comparison of cytochrome c distribution (left) and morphology of mitochondria (right) in cells stained with anti-cytochrome c and Mitotracker Red. (A) Before the UV-treated cell entered apoptosis, cytochrome c was distributed mainly in mitochondria, which had the normal filamentous shape. (B) In a small percentage of cells undergoing UV-induced apoptosis, cytochrome c was released into the cytosol while mitochondria still remained in filamentous shape. (C) In some UV-induced apoptotic cells, cytochrome c was released into the cytosol and the mitochondria became swollen. (D,E) Results similar to those in B were observed in apoptotic cells induced by TNF (D) or actinomycin D (E) treatments. Scale bar: 20 µm.