FIG. 2.

Domain structure and expression of HCV NS5A. (A) Schematic diagram of the functional domains of NS5A and design of the constructs used in the study (genotype 1b NS5A protein numbering). The N-terminal amphipathic helix of NS5A (black box) is responsible for the interaction of NS5A with membranes. NS5A is organized into three domains that are separated by low-complexity sequences, indicated by black boxes. The NS5A constructs used all lacked the N-terminal amphipathic helix and were designed to include an N-terminal Strep tag and a C-terminal hexahistidine tag. (B and C) SDS-PAGE and Western blot analysis of the NS5A(ΔAH) and NS5A domain constructs purified by nickel affinity and Streptactin tag affinity chromatography. Coomassie brilliant blue-stained gels and Western blots (WB) using anti-NS5A antibodies for NS5A proteins of genotype 1b strain J4 (B) and genotype 2a strain JFH-1 (C) are shown.