Fig. 4.

DU is an inhibitory factor in IFN-β signaling pathway. (A-C) 293T cells were co-transfected with ISRE-luc/NF-κB-luc/IFN-β-luc plasmids (100 ng), Flag-RIG-I/Flag-MDA5/Flag-MAVS/Flag-TBK1, and pEGFP-DU expression plasmids or empty vector, then, the luciferase activity of ISRE, NF-κB, and IFN-β promoters was examined. (D and E) 293T cells were co-transfected with ISRE-luc/IFN-β-luc plasmids and pEGFP-DU expression plasmids or empty vector, then, the luciferase activity of ISRE and IFN-β promotors was tested. Differences in data considered statistically significant at p-value less than 0.05 (^* P<0.05, ^** P<0.01, ^*** P<0.001, ^**** P<0.0001, and NS: No significant). Data are representative of three independent experiments. ISRE: Interferon stimulated response element, CMV: Cytomegalovirus, RIG: Retinoic acid-inducible gene I, MDA5: Melanoma differentiation-associated gene 5, MAVS: Mitochondrial antiviral signaling protein, TBK1: TANK-Binding kinase 1, NF: Nuclear factor, IFN: Interferon, IRF3: Interferon regulatory factor 3, and pEGFP-DU: dUTPase