Fig 3.

HCV infection or transfection of HCV core/NS5A inhibits IRF-1 and USF-1 expression in hepatocytes. (A) Real-time PCR analyses for the mRNA expression status of IRF-1 and USF-1 in HCV genotype 1a- or 2a-infected IHH or Huh7 cells. The results were normalized with 18S RNA and are presented as mean values and standard deviations from triplicate experiments. The asterisks indicate statistical significance (***, P < 0.001). (B) IHH and Huh 7 cells were infected with HCV genotype 1a or 2a. Whole-cell lysates were prepared 5 days after infection. The expression levels of transcription factors, USF-1, phospho-STAT3, IRF-1, and PU.1, were detected by Western blot analysis. (C) Real-time PCR analyses for the mRNA expression status of IRF-1 and USF-1 in IHH transduced with lentivirus vector expressing core or NS5A from HCV genotype 1a. (D) Similar analyses were performed using Huh-7 cells transiently transfected with mammalian expression vector encoding core or NS5A from HCV genotype 1a. The results in both panels C and D were analyzed as described for panel A. The asterisks indicate statistical significance (*, P < 0.05; ***, P < 0.001). (E) Huh7 cells were transiently transfected with the HCV core, NS2, NS3/4A, or NS5A genomic region, and expression of transcription factors was analyzed similarly by Western blotting after 48 h. (F) Huh7 cells were transiently transfected with HCV core or NS5A and treated or not with 1,000 U/ml of IFN-γ for 2 h, and expression of the transcription factors was analyzed by Western blotting. The blots were reprobed with an antibody to actin for comparison of the protein loads in each lane.