FIG. 4.

TRAIL-induced JNK activation was impaired in both RIP^−/− and TRAF2^−/− cells. (A) Wild-type, RIP^−/−, and TRAF2^−/− mouse fibroblasts were treated with GST-TRAIL (10 μg/ml) for 30 min, and a JNK assay was performed. JNK1 was detected by Western blot analysis as described in Materials and Methods. Nontreated cells served as controls. (B) Wild-type, RIP^−/−, and TRAF2^−/− mouse fibroblasts were treated with IL-1 (4 ng/ml) for 10 min, and a JNK assay was performed. Nontreated cells served as controls.