Figure 4

The mutant hydrophobic tail of Bax alone targets GFP to mitochondria. (A) Schematic representation of the construction of GFP linked to the last 21 amino acids of wild-type Bax (GFP–21), and the last 20 amino acids of the S-184 mutant (GFP–20). (B) Cos-7 cells transiently expressing GFP linked to Bax tails examined by confocal microscopy display a subcellular distribution similar to that of the respective version of full-length Bax. GFP–21 displays a diffuse cytosolic distribution, whereas GFP–20 co-localizes with the mitochondria. Cells were treated with 20 ng/ml Mitotracker red CMXRos. Each field was visualized independently by laser fluorescence confocal microscopy at the appropriate wavelength for Mitotracker red CMXRos (Mito), for GFP and then for the two images overlaid (overlay). Bar, 25 m.