FIG. 4.

Effects of proteasome inhibitors on WHV gene expression. HepG2 cells were infected with recombinant bvWHV at a MOI of 50 and treated with three different proteasome inhibitors, lactacystin (LC), epoxomicin (EPOX), and MG132, at different doses. The cells were harvested for analysis 3 days postinfection. (A) Effects on WHV replication. The core-associated DNA was extracted for the detection of replicative intermediates by Southern blotting with WHV-specific probe. The signal intensities were quantitated and normalized to the control (control as 100), and means from three independent experiments are shown at the bottom. The WHV marker is full-length WHV DNA. (B) Effect on WHV transcription. Total RNA was isolated for the detection of viral transcripts by Northern blotting. The 28S and 18S RNAs were used as loading controls. (C) Effect on viral antigen production. Culture medium was assayed for WHV surface antigen (WHsAg). Results are representative of three independent experiments.