FIG. 6.
Impact of the silencing of ANXA2 and other annexins on HCV or dengue virus titers. Huh7-Lunet cells were transfected with the indicated siRNAs, electroporated with a second dose of the same siRNA together with viral genomes, and analyzed for ANXA2 knockdown efficiency (A) and titers of HCV (B and C) or dengue virus (D). (A) Reduction of ANXA2 levels after knockdown. Shown is a Western blot of cell lysates harvested 48 h postelectroporation of Huh7-Lunet cells with HCV JC1 in vitro transcripts and the indicated siRNAs. Antigens were detected by monoclonal mouse antibodies directed against NS5A, β-actin, and ANXA2 as indicated on the right. (B) ANXA2 knockdown impairs the production of infectious HCV. The relative infectivity in supernatants at 24 and 48 h after electroporation with JC1 and the indicated siRNA is shown. Mean values and standard deviations of viral titers from seven independent experiments are given in percentages normalized to TCID50 titers in mock-silenced cells. (C) No impact of ANXA4 or ANXA5 knockdown on viral titers. HCV infectivity titers in supernatants harvested 48 h after the electroporation of cells with HCV JC1 full-length RNA and the indicated siRNAs are shown. The TCID50/ml of a representative experiment are shown. Knockdown efficiency was checked by Western blotting (not shown). (D) No reduction of dengue virus titers upon ANXA2 silencing. Titers of dengue virus genotype 2 in supernatants harvested 48 h after the electroporation of presilenced cells with DV full-length RNA and siRNAs shown as the TCID50/ml of a representative experiment. An siRNA directed against HCV was used as a negative control in this experiment.