Schematics of HCV -2/+1 frame mutants.

(A) Putative -2/+1 frame protein products of HCV. Translational frameshift sites are indicated with bent arrows. White bars represent zero frame and gray bars, protein regions coded by the -2/+1 frame. Dotted lines indicate positions where the majority of -2/+1 frame sequences terminate, such as stop codon at codon 126 in the -2/+1 frame for JFH1. Numbers represent codons, and locations of Δ and Δ4 mutations are marked with stars. (B) JFH1 constructs. Putative RNA elements for the generation of various -2/+1 elements and nt. substitutions introduced in JFH1 constructs are shown. Numbers represent nucleotide positions within the JFH1 polyprotein sequence.