FIG. 8.
Effects of IRF-3 point mutations on DNA binding activity. (A) EMSA was performed on whole-cell extracts (20 μg) derived from 293 cells transfected with various IRF-3 expression plasmids as indicated. At 24 h posttransfection, cells were infected with Sendai virus for 12 h or left uninfected. The 32P-labeled probe corresponds to the ISRE of the ISG15 gene: 5′-GATCGGGAAAGGGAAACCGAAACTGAAGCC-3′. (B) Whole-cell extracts (20 μg) from panel A were analyzed by immunoblotting with anti-IRF-3 antibody. IRF-3(5D), IRF-3(5D-J2A), and IRF-3(7D) proteins migrated more slowly than wtIRF-3, at a position consistent with phosphorylated IRF-3; arrows indicate positions of the different forms of IRF-3.