FIG. 3.

Activated JNK causes cell death. (A) CHO cells were cotransfected with a GFP expression vector together with expression vectors for the MKK7-JNK1 fusion protein (wild type and phosphorylation defective) or an active fragment of the BH3-only protein Bid (tBid). The cells were examined at 40 h posttransfection by fluorescence microscopy. The data presented are representative of three independent experiments. (B) CHO cells were transfected with empty vector or with the indicated expression plasmids. The cells were harvested after 40 h and stained with crystal violet. The data shown are the means ± SD for three independent experiments. (C, D) CHO cells were cotransfected with the indicated expression vectors and a luciferase expression vector (pCDNA3-Luc) to monitor cell viability. The cells were harvested at 40 h posttransfection and luciferase activity was measured. The data shown are the means ± SD for three independent experiments.