Figure 1.

Mutational analysis of hFis1 domains required for mitochondrial fission and apoptosis. (A) Cartoon of constructs used in this study. (B) Representative images of mitochondrial morphology in wt MEFs cotransfected with the indicated plasmid and mtRFP. Forty-eight hours after transfection fluorescence of mtRFP was visualized by confocal microscopy. Bar 15, μm. (C) Morphometric analysis of mitochondrial shape. Experiments were carried exactly as in A. Data represent mean ± SE of five different experiments. (D) Deletion of the first α-helix and K148R point mutation abolish hFis1-induced apoptosis. wt MEFs were cotransfected with GFP and the indicated plasmids, and after 48 h apoptosis was determined as the percentage of GFP-positive, Annexin-V–positive cells by flow cytometry. Data represent mean ± SE of six independent experiments.