Figure 3.
Effect of caspase inhibitors on FasC- and reaper-induced cell death in Schneider cells. (A and B) Effect of the peptide inhibitors. Samples (1 × 105) of Drosophila Schneider cell transformants harboring the expression plasmid for FasC (A) or reaper (B) were treated at 25°C for 24 hr with 0.5 mM CuSO4 in the presence of the indicated concentrations of Ac-DEVD-CHO (▪), Ac-YVAD-CHO (•), Ac-YVAD-CMK (▴), Z-LLL-CHO (○), or TPCK (▵). The cell viability was determined by MTT assay, and values are expressed as percentages of the control cells, which were cultured without CuSO4. (C) Effect of crmA and p35. The transformants harboring the expression plasmids for FasC alone (lane 1), FasC and crmA (lanes 2 and 3), FasC and p35 (lanes 4 and 5), reaper alone (lane 6), reaper and crmA (lanes 7 and 8), or reaper and p35 (lanes 9 and 10), were treated at 25°C for 18 hr with 0.5 mM CuSO4. The cell viability was determined by MTT assay.