FIGURE 6.

Expression of B- and C-RAF delays BAD-mediated apoptotic death of HEK293 cells following growth factor removal. A and B, HEK293 cells were transiently transfected in triplicates with the indicated expression vectors (ratio 1:1). 16 h post-transfection, cells were cultivated for an additional 30 h in medium supplemented with 0.3% serum. Cell viability was assessed by trypan blue staining. Mean and S.D. values are shown. The experiment was repeated twice. C, colony formation assay shows reproductive survival of triplicate cultures of NIH 3T3 cells stably expressing either empty vectors, BAD alone, BAD in combination with B-RAF or activated C-RAF (C-RAF-DD), and B-RAF and C-RAF-DD alone. BAD phosphorylation by RAF protected cells from apoptosis and led to an increased number of colonies.