Induction of cell death in Hct116 cells by Tax + Jun kinase. Hct116 cells were transfected with pCMV-beta-gal and control plasmid pUC19 or the indicated plasmids. Reduction in beta-gal values reflects cell death. Cells transfected with CMV IE-driven JNK-expression plasmid (pCMV-HA-JNK) + CMV-Tax showed significantly lower level of beta-gal values, while cells with other combinations of transfected DNA showed higher levels. TaxΔ2-58 is an inactive Tax mutant. Transfection efficiencies achieved in the experiments were approximately 50%. Values represent averages from three independent experiments.