Figure 4.

Sensitivity to the TNF-mediated death signal is not enhanced by overexpression of hCath-L or hCath-B. (A) HeLa cells were transfected with pLuc, hCath-L, or hCath-B expression vectors, and 36 h post-transfection were incubated in the absence or presence of 5 μg ml⁻¹ CHX or 10 ng ml⁻¹ TNF +5 μg ml⁻¹ CHX. After 10 h of treatment, cells were harvested for propidium iodide FACS analysis. Transfection efficiency in this experiment was 40% as determined by pEGFP cotransfection and EGFP FACS analysis. (B) HeLa cell pools selected for stable expression of pcDNA3, hCath-L, or hCath-B were incubated in the absence or presence of 5 μg ml⁻¹ CHX or 10 ng ml⁻¹ TNF+5 μg ml⁻¹ CHX. After 12 h of treatment, cells were harvested for propidium iodide FACS analysis. (C) McA RH 7777 rat hepatoma cells were transiently transfected with pLuc, hCath-L, or hCath-B expression vectors, and 36 h post-transfection were incubated in the absence or presence of 1 μg ml⁻¹ CHX, 10 ng ml⁻¹ TNF+1 μg ml⁻¹ CHX, or 50 ng ml⁻¹ TNF+1 μg ml⁻¹ CHX. After 12 h of treatment, cells were harvested for propidium iodide FACS analysis. Transfection efficiency in this experiment was 40% as determined by pEGFP cotransfection and EGFP FACS analysis. Statistics are as given in Figure 1.