FIG. 4.

Mutant L60V core protein alone is sufficient to induce a low-secretion phenotype. WT and mutant core proteins expressed from plasmids SVC WT adr and SVC L60V, respectively, were supplied in trans to a core-defective and replication-defective HBV mutant, 1903 (42). Their respective complementation effects on intracellular HBV DNA replication (a) and virion secretion (b) were compared. (c) Furthermore, WT core protein can rescue the low-secretion phenotype of mutant L60V via cotransfection. The analysis of extracellular virion particles was performed by gradient centrifugation as described in the legend for Fig. 2. RC, relaxed-circle form DNA; SS, single-stranded DNA.