FIG. 2.

Lack of Cif activity in the cytosol of Bcl-2:HL-60 cells. (A) Bcl-2 is overexpressed in the cytosol. Western blot analyses of Bad, Bak, Bax, and Bcl-2 contained in 100 μg of total proteins from HL-60 and Bcl-2:HL-60 S-100 extracts. (B) Bcl-2:HL-60 cells were left untreated or treated with 5 μM STS for 60 min. S-100 cytosolic extracts were then prepared from the cells and incubated with HL-60 mitochondria for 15 min at 37°C. The samples were then centrifuged to pellet the mitochondria. The pellet (P) and supernatant (S) were separated, and the cytochrome c (Cyt. c) content in each fraction was determined by Western blot analysis.