Figure 7
The effect of the length of PA-X in suppressing IFN-I expression.
(A) Effect of PA-X on IFN-α and IFN-β mRNA expression in PAM cells, which were either uninfected or infected with SIV with truncated or full length PA-X at an MOI of 1.0. Total RNA was extracted from the infected cells at the indicated time points, the expression levels of IFN-α and IFN-β mRNA were quantified by real-time PCR. (B) IFN-α and IFN-β mRNA expression in lung homogenates at 3 dpi and 5 dpi. Total RNA was extracted from 100 μL of the homogenates, the expression levels of IFN-α mRNA and IFN-β mRNA were quantified by real-time PCR. Copy number in each sample was calculated using a standard curve of 10-fold serial dilutions of swine IFN-α or IFN-β gene product. Fold change indicates ratio of copy number of each sample over mock infection samples. (C) Luciferase reporter-mediated assay to quantify the PA-X protein inhibition effects on IFN-β promoter activation. Data are presented as means ± SD of three independent experiments. *the value of Sw-41X(WT) was significantly different from that of Sw-61X (P < 0.05, ANOVA).
