Figure 3. Drug-induced activation of procaspases does not occur in APAF1-silenced Jurkat cells.

(A) Wild-type (WT), control-vector-transfected (pSUP) and Apaf-1-deficient (clones 4 and 6) cells (10⁶/ml) were cultured with or without 10 μM ETOP or 100 nM MITOX for 6 and 12 h, harvested and lysed for Western blotting. (B) Duplicate aliquots of cells at the 12 h time-point were harvested for caspase activity determination. Enzyme activity was monitored by the production of AMC. RFU, relative fluorescence units.