FIG. 8.

Role of JNK in TNF-stimulated cytokine expression. (A) WT and Jnk^−/− fibroblasts were starved for 3 h and then treated with TNF-α (10 ng/ml). Total RNA was purified, and 5 μg was used for RNase protection assays to measure the amount of TNF-α, IL-6, IFN-γ, LIF, GM-CSF, M-CSF, and ribosomal protein L32 mRNA. The ratio of cytokine mRNA/L32 mRNA was calculated and is presented as the relative amount of cytokine expression. The data shown are representative of three independent experiments. (B) RNase protection assays were used to measure the amount of TNF-α, IL-6, and IFN-γ mRNA expressed by WT and Mkk^−/− cells.