Figure 4.

Tripartite interaction between the L, S and core proteins. Huh7 cells were cotransfected with a plasmid encoding the core protein, and a plasmid encoding S-His, or L-His, or S-His plus untagged L. Three days post-transfection, cells were analyzed by confocal microscopy and co-IP. (A) Cells were fixed and double-stained with anti-His (in green) and anti-HBc (in red) antibodies, and nuclei were labeled with DAPI (in blue). S-His was colocalized with WT core protein in the presence of untagged L proteins (bottom row). (B) Histogram of r values (***p value < 0.001). (C) Huh7 cell lysates were collected and 400 µg of total protein was subjected to IP with an anti-His antibody. The immunoprecipitated samples were blotted and the membranes were probed with anti-HBs (IP) or anti-HBc (Co-IP) antibodies. Core protein co-IP was observed with S-His if untagged L was also produced.