FIG 3.
SVV 3Cpro mediates the cleavage of MAVS, TRIF, and TANK. (A) Luciferase activity assay from 293T cells transfected with the indicated adaptor-expressing plasmids or empty vector for 20 h and then infected or not with SVV (MOI, 5) for another 9 h. (B) Luciferase activity assay from 293T cells cotransfected with the indicated adaptors plus SVV 3Cpro or empty vector for 24 h. (C) IFN-β and ISG56 mRNA expression as assessed by qRT-PCR from 293T cells cotransfected with the indicated adaptors plus SVV 3Cpro or empty vector for 24 h. (D) Immunoblot analysis of 293T cells cotransfected with the indicated adaptors (N-terminally Flag tagged) plus SVV 3Cpro or empty vector for 24 h. (E to G) Plasmids expressing Flag-MAVS (E), Flag-TRIF (F), and Flag-TANK (G) were cotransfected with plasmids expressing HA-tagged 3Cpro derived from EMCV (JQ864080) and EV71 (JN230523) into 293T cells. The protein patterns were detected by immunoblotting. (H) Immunoblot analysis of 293T cells infected with SVV (MOI, 5) for the indicated times. Antibodies against MAVS, TANK, and SVV VP1 were used. (I) Immunoblot analysis of 293T cells transfected with Flag-TRIF for 20 h and then infected with SVV (5 MOI) for the indicated times. Antibodies against TRIF and SVV VP1 were used. Data are shown as means ± SD. *, P < 0.05; **, P < 0.01; ***, P < 0.001. Data are representative of at least three independent experiments.