Figure 3.
cFLIPL inhibits IRF7 phosphorylation. A, HeLa cells were transfected with 1.5 μg of pIFNα and 6 μg of pCI, pcFLIPL or pAIP. 24 h post-transfection, cells were incubated with medium lacking or containing 3 μm CpG-A for 3 h. Cells were lysed, and immunoblotting was performed to detect phospho-IRF7, IRF7, FLAG-tagged cFLIPL, myc-tagged AIP, and β-actin proteins. B, 293T cells were co-transfected with 450 ng of pifna6-luc; 50 ng of pRL-TK; 1000 ng of pCI, cFLIPL, or pAIP; and 500 ng of pCI or pIRF7CA. 24 post-transfection, cells were lysed, and luciferase activities were quantified. Luciferase assays are representative of three technical replicates, and all luciferase assays were performed at least three times. Results are shown as -fold induction of luciferase activity relative to unstimulated, pCI-transfected cells. Immunoblot analysis of whole-cell lysates also was performed to detect FLAG-tagged cFLIPL and myc-tagged AIP. C, 293T cells were transfected with 500 ng of IRF7, 500 ng of pCI or pMAVS, and1000 ng of pCI, pcFLIPL, or pnsp11. 24 h post-transfection, cells were lysed, and immunoblotting was performed to detect phospho-IRF7, IRF7, FLAG-tagged cFLIPL, FLAG-tagged nsp11, and β-actin proteins. The experiments shown here are representative of experiments performed at least three times. Data are expressed as the mean ± S.D. Statistically significant differences in experimental samples compared with cells transfected with empty vector are denoted (*, p < 0.05).