Fig. 2.

3CLSP suppression of IFN-β induction is dependent on protease activity. HEK-293T cells were co-transfected with IFN-β–Luc, IRF3–Luc or NF-κB–Luc along with pRL-TK plasmid and the 3CLSP mutants/3CLSP expression plasmids (0.8 μg). An empty vector (pCAGGS-HA) was used as a control. At 24 h post-transfection, cells were treated with SeV for 8 h and then luciferase activity was measured. *P < 0.05 (WT 3CLSP vs 3CLSP mutants). WT 3CLSP significantly inhibited IFN-β expression compared with the mutants and mock cells. Results are shown as means ± sd;ns, not significant.