PKR is required for IRF3 activation during VVΔE3L infection.

WT and Pkr-/- MEFs were infected with the indicated viruses (VVΔE3L and EMCV: MOI = 3, SeV: 200 HA units/mL) for 8 h. IRF3 nuclear translocation and total IRF3 expression were measured by western blotting of nuclear and cytoplasmic extracts. Detection of histone H3 and tubulin were used as loading controls for nuclear and cytoplasmic compartments, respectively. The data shown are representative of three independent experiments.