Figure 4.

BFRF1 dose-dependent represses IFN-β promoter activity at the level of IKKi. IFN-β-Luc reporter and pRL-TK control plasmid were co-transfected with RIG-IN (A), IPS-1 (B), TBK1 (C), IKKi (D), IRF3/5D (E), or IRF7/6D (F) expression plasmid into HEK293T cells, together with the indicated amounts of BFRF1 expression plasmid for 24 h, then luciferase activity was analyzed by DLR. The expressions of related adaptor and viral proteins were also detected by WB using specific tag Abs, and β-actin was used to verify equal loading of protein in each lane. Statistical analysis was performed using Student’s t test. ns, not significant; **P < 0.01; ***P < 0.001.