File:Viruses-11-00030-g002.png

English: HCV virus and replicon organization and membrane organization of the viral proteins. (a) The HCV genome is a positive strand RNA containing a single open-reading frame (from AUG to stop) surrounded by 5′ and 3′ highly structured non-translated regions (NTRs). Translation of the polyprotein is enhanced by miR-122 binding in the 5′NTR as indicated. Translation is initiated at the internal ribosomal entry site (IRES). The polyprotein is cleaved by cellular (white arrowheads) or viral (black arrowhead) proteases. C: Core protein. All Non-Structural (NS) proteins (including p7) are in black. (b) Example of organization of a HCV subgenomic replicon that were extensively used for antiviral drug screenings, they contain all the proteins necessary and sufficient for HCV RNA replication. Neomycin: Neomycin resistance gene. ECMV: Encephalomyocarditis Virus. (c) Membrane association of HCV proteins. Hatched bars represent amphipathic alpha helix or transmembrane domains anchoring the proteins to the membrane. Two examples of essential cellular proteins interacting with NS5A are shown. The three main types of inhibitors used in the clinic (indicated in red by their suffix) are indicated next to their target.