Fig. 1.

HCV NS5A downregulates GADD45α promoter activity, mRNA transcription and protein expression. (a) A GADD45α promoter–luciferase (Luc) reporter plasmid (1.0 µg) was co-transfected with the indicated plasmids at the indicated doses (µg) into Huh7 cells for 48 h and a luciferase assay was performed. (b) GADD45A mRNA levels were analysed by quantitative PCR. GADD45α mRNA levels were normalized to glyceraldehyde-3-phosphate dehydrogenase (GAPDH) levels to calculate the GADD45/GAPDH ratio, with the control non-transfected Huh7 cells having a ratio of 1. (c) Representative Western blot for GADD45α, NS5A and β-actin expression (left). Quantification of the GADD45α protein levels in Huh7-2-3 cells and in Huh7 cells transfected with NS5A-expressing vector or empty vector (right). Results are shown as means±sem of three independent experiments. *P<0.05.