N-terminal region of NS2 protein is involved in the antiviral effects of NS2-specific aptamer.
(A) Schematic of NS2. (B) Confirmation of the expression of different truncated versions of NS2 protein. Different truncated versions of NS2 gene were amplified and cloned into pcDNA3.1/V5-His. Huh7.5 cells were transfected by these plasmids. Different truncated versions of NS2 protein were confirmed using anti-His antibody by western blot. (C) Binding affinity of different truncated versions of NS2 to the aptamer. The cells were treated as described in part B. The protein was isolated from the cells and binding affinity of truncated versions of NS2 to aptamer was determined by ELONA assay. The empty vector pcDNA3.1/V5-His was used as a control vector. The data represented means of three independent experiments performed in triplicate. *P<0.05 verse library. (D) Titration of HCV particles produced in HCV-infected cells transfected by truncated versions of NS2 with aptamer treatment. HCV-infected Huh7.5 cells were transfected by different truncated versions of NS2. Then the cells were treated by aptamer NS2-2 or library for 72 hours. The cell culture supernatants were harvested and titered by FFU assay on naïve Huh7.5 cells. The infectivity titers are the average of three independent experiments. *P<0.05 verse vector-transfected cells.