FIG 4.

Sam68 directly binds to HCV RNA. (A and B) Huh7.5 cells were infected with HCV at an MOI of 0.1 for 72 h. The cells were harvested and immunoprecipitated with control IgG or anti-Sam68 antibody or anti-PCBP2 antibody. (A) RNA was extracted from the precipitate complex and subjected to RT-PCR or qRT-PCR analysis. (B) Protein from the precipitate complex was detected by immunoblotting with the anti-Sam68 and PCBP2 antibodies. (C) Purified Sam68 protein (0.5 μg) and in vitro transcribed JFH1 RNA (1 μg) were incubated in binding buffer for 20 min at room temperature followed by RIP analysis. (D) Gel shift analysis of complex formation between 30 pmol of purified Sam68 protein and 10 pmol of in vitro transcribed JFH1 RNA. Arrows denote the positions of unbound RNA and RNA-Sam68 complexes.