Fig 1.

A JFH1-based intergenotypic chimeric genome encoding the mutant p7 protein of HCV-A with an amino acid sequence identical to that of J4 p7 is replication competent but exhibits delayed secretion of infectious virions. (A) Schematic representation of the intergenotypic chimeric JFH1 genome encoding mutant p7 (JFH1-J4p7). The mismatched residues are identified by filled circles. (B). HL1 cells were transfected with wild-type JFH1 and JFH1-J4p7 transcripts. The viral titers in the supernatant fluids collected at 72 h posttransfection (PT) and at passages 1, 2, 3, 4, and 6 were determined (see Materials and Methods). Wild-type JFH1 and JFH1-J4p7 infectivity titers are represented by shaded and filled bars, respectively. FFU, focus-forming units. (C) At 72 h after transfection with JFH1 or JFH1-J4p7, intra- and extracellular core protein quantities were measured and were normalized to JFH1 core quantities as described in Materials and Methods.