Figure 2.

Mitochondrial targeting of proteins in cells expressing γ₂MITO. (A) Diagrammatic representation of γ-subunit constructs, showing N-terminal mitochondrial targeting signal (mito), myc epitope tag (myc), and C-terminal prenyl modification. (B) Immunofluorescence microscopy of CHO cells transfected with wild-type γ₂ (a–c) or γ₂-MITO (d–f). Cells were costained with antibody to γ₂ (a and d) and mitochondrial Hsp60 (b and e). c and f show the overlap (yellow) of the two antibody stains. (C) Quantitative analysis of the calculated percentage of overlap between immunofluorescent stain for the appropriate mitochondrial probe (anti-γ₂ or anti-Hsp60, as indicated in the figure legends) and the stain for the indicated G protein subunit in cells cotransfected with no γ-subunit, β₁ plus γ₂MITO, or β₁ plus γ₂C68S-MITO. Bars represent means ± 2 SEM (n = 4).