Fig 1.

VACV activation of JNK1/2 requires either MKK4 or MKK7. VACV infections were carried out using mouse fibroblast A31 cells (A, E, and F), WT MEFs (B, C, D, and G), MKK4/7^−/− MEFs (B), MKK4^−/− MEFs (C), and MKK7^−/− MEFs (D). Cells were either uninfected or infected (MOI, 10) for the times shown. Whole-cell extracts (WCEs) were collected and analyzed by Western blotting. (A to G) (Top) Immunoblots with anti-phospho JNK1/2/SAPK antibody; (bottom) immunoblot with anti-β-actin or total ERK12 as a loading control, as indicated. (F and G, middle) Immunoblots were also probed with antiviral A36R protein and anti-phospho-c-Jun antibodies, respectively. (E) Cells were infected with UV-inactivated virus (MOI, 10) or with the nonirradiated virus (MOI, 1, 5, or 25), as indicated. UN, uninfected. (F and G) Cells were incubated with araC (40 μg/ml) or with JNKi (0.4 to 40 μM) for 30 min prior to virus infection. Incubation was carried in the continued presence of the inhibitors. The molecular masses (kDa) are indicated on the left. Data are representative of three independent experiments with similar results.