Figure 4.

Staurosporine treatment of HL-60 cells promotes membrane association of Bax. HL-60 cells were treated either in absence (lanes a–c) or in the presence of 1 μM staurosporine for 2 h (lanes d–f) and 4 h (lanes g–i). The cells were collected, hypotonically lyzed, homogenized with a Dounce homogenizer, and fractionated into soluble (lanes a, d, and g), high-speed membrane pellet (lanes b, e, and h), and nuclear fractions (lanes c, f, and i) by differential centrifugation. The samples were analyzed by Western blotting with anti-hBax 2D2 and anti-hBcl-2 124 monoclonal antibodies.