Inhibitory effect of hA3G on enzymatic activities of HCV NS3.

<p>(A) hA3G inhibited activity of HCV NS3 helicase (left) in a cell-free reaction system, however, it showed no significant impact on NTPase (middle) and serine protease (right) activities of NS3, even at concentration of 10μg/mL. Presented were mean ± SD (n = 3). *<i>P</i><0.05 and **<i>P</i><0.01: treated <i>vs</i>. 0μg/mL hA3G-HA group; ^#<i>P</i><0.05: 10μg/mL <i>vs</i>. 2μg/mL hA3G-HA group. (B) Ectogenous hA3G restricted HCV replication in Huh7.5 cells. HCV infected (with 45 IU/cell) or uninfected Huh7.5 cells were transfected with phA3G-HA or plasmid control; 48hrs later, the cell lysates were extracted and analyzed with western blot to detect HCV core (top band), intracellular total hA3G (middle band) and internal-control Actin (bottom band). The scanned intensity histogram showed the average value of western blot (n = 3). The bands presented below showed the results of a representative experiment. *<i>P</i><0.05: HCV infection with or without phA3G-HA transfection <i>vs</i>. 0μg/mL phA3G-HA with no HCV infection; ^#<i>P</i><0.05: HCV infection with 0.02μg/mL phA3G-HA transfection <i>vs</i>. HCV infection alone. (C) Ectogenous NS3 reversed the restrictive activity of hA3G on HCV. HCV infected (with 45 IU/cell) Huh7.5 cells were co-transfected with 0.2μg phA3G and 0.2μg pNS3 (left)(or pNS3/4A (right)); 72hrs later, the cell lysates were extracted and analyzed with western blot. The histogram showed the average density value of western blot (n = 2). The bands presented below showed the results of a representative experiment. **<i>P</i><0.01: transfected with phA3G <i>vs</i>. untransfected with phA3G and pNS3 (or pNS3/4A); ^#<i>P</i><0.05: co-transfected with phA3G and pNS3 (or pNS3/4A) <i>vs</i>. transfected with phA3G alone.