SARS-CoV-2 N protein inhibits SeV and IL-1β–mediated NF-κB promoter’s activation. (A) HEK293 cells were transfected with plasmids expressing the indicated SARS-CoV-2 proteins. At 48 h after transfection, lysates were subjected to immunoblot analysis. (B) Dual luciferase reporter system screened SARS-CoV-2 proteins that interfered with the activation of the NF-κB pathway. (C and D) HEK293 cells were transfected with NF-κB-Luc, along with plasmids encoding Flag-SARS-CoV-2 N protein or Flag-SARS-CoV N protein. At 24 h after transfection, cells were stimulated by SeV for 10 h (C) or IL-1β for 4 h (D), and luciferase activity was measured. Graphs show mean ± SEM (n = 3 in C and D). ***P < 0.001, ****P < 0.0001, ns, not significant (unpaired, two-tailed Student’s t test). Data in A are expressed at least twice in independent experiments, and one representative is shown. Data in C and D are expressed in at least three independent experiments. Source data are available for this figure: SourceData FS1.