FIG. 4.

HCV transactivates SREBP-1. (A) Luciferase reporter gene assay. Huh-7 and HCV-infected cells were transfected with 500 ng of FAS-700-Luc (wt) and FAS-mut-Luc reporter plasmids as described for Fig. 3. Results are shown as means (± standard deviations) of two independent experiments, each performed in duplicate. (B) Western blot assays. Cellular lysates from Huh-7 and HCV-infected cells were subjected to Western blot analysis using respective antibodies as indicated. Lanes 1, Huh-7 cell lysates; lanes 2, HCV-infected cell lysates. (C) Quantitative real-time PCR analysis. Total cellular mRNA was extracted, and cDNAs were prepared from Huh-7 (lane 1) and HCV-infected (lane 2) cells. Equal amounts of cDNAs were subjected to quantitative RT-PCR using LXR-specific primers. Hypoxanthine phosphoribosyltransferase (HPRT) mRNA was used as an internal control. The results represent means ± standard deviations of two independent experiments performed in triplicate. (D) Huh-7 cells and HCV-infected cells were transfected with LXR-responsive pLXRE-Luc luciferase plasmid derived from the SREBP-1c gene. Thirty-six hours posttransfection cellular lysates were prepared and assayed for luciferase activity. The data represent means ± standard deviations of three independent experiments performed in duplicate.