Fig. 4: PRMT9 negatively regulates MAVS-mediated signaling.

a Immunoblot analysis of total and phosphorylated (p-) TBK1, total and phosphorylated (p-) IRF3, total and phosphorylated (p-) IκBα in lysates of HEK293T cells transfected with control vector or Flag-PRMT9 infected with SeV for 0–8 h. c, e Immunoblot analysis of total and p-TBK1, total and p-IRF3, total and p-IκBα in Prmt9^CKO and Prmt9^WT peritoneal macrophages cells, followed by infection with SeV or HSV-1 for 0-8 h. b, d and f Densitometric analysis of protein expression levels was quantitated by“ImageJ” software. Ratio: p-TBK1/TBK1, p-IRF3/IRF3 or p-IκBα/ IκBα, bar graphs are presented relative to the second lane. Data are represented as mean ± SD (two-tailed student’s t-test was performed, for b, left panel: *p = 0.0132, 0.0354 in sequence, middle panel: *p = 0.0232, 0.0278 in sequence, right panel: **p = 0.0082, 0.0010 in sequence; for d, left panel: **p = 0.0044, *p = 0.0126 in sequence, middle panel: *p = 0.0129, **p = 0.0061 in sequence, right panel: *p = 0.0486, **p = 0.0041 in sequence; n = 3 independent experiments). g Immunoblot analysis of IRF3 in cytoplasmic (Cyt) and nuclear (Nuc) in Prmt9^CKO and Prmt9^WT peritoneal macrophages cells infections with SeV for 0–8 h. h Densitometric analysis of protein expression levels, bands were normalized with individual actin or PCNA, bar graphs are presented relative to the lane 1. Data are represented as mean ± SD (two-tailed student’s t-test Prmt9^WT vs. Prmt9^CKO, left panel: **p = 0.0095, *p = 0.0297, 0.0176 in sequence, right panel: ***p = 0.0005, *p = 0.0341, 0.0476 in sequence; n = 3 independent experiments). i Confocal microscopic images of IRF3 (Red) in HEK293T cells transfected with control vector or Flag-PRMT9 (Green) infected with SeV for 0–8 h, Scale bar, 10 μm, ***p = 0.0008. *P < 0.05; **P < 0.01; ***P < 0.001; ns, not significant (two-tailed student’s t-test). Similar results were obtained from three independent experiments.