(A) pHBV-luc and its derivatives, pHBV-G1620A-luc and pHBV-G1620C-luc, were co-transfected with either an empty vector or HBx expression plasmid into HepG2 cells, followed by luciferase assay (n = 4). (B) pHBV-NRE-luc and its derivatives, pHBV-NRE-G1620A-luc and pHBV-NRE-G1620C-luc, were co-transfected with either an empty vector or HBx expression plasmid into HepG2 cells, followed by luciferase assay (n = 4). (C) HepG2 cells were transfected with 1.2-mer WT or its derivatives, 1.2-mer HBV G1620A and 1.2-mer HBV G1620C for 48 h in the presence or absence of 5 μM 5-Aza-2′dC. Levels of NREBP bound on the NRE in HBV cccDNA were determined by ChIP assay (upper panels). Levels of HBc and HBx were determined by Western blotting (lower panels). (D) Levels of extracellular HBV particles released from cells prepared as in (C) were determined by IP-coupled conventional PCR and real-time PCR (n = 4). (E) HepG2 cells transfected with the NTCP expression plasmid were infected with the indicated HBV at an MOI of 1.0 for 48 h, followed by Western blotting. (F) Levels of extracellular HBV particles released from cells prepared as in (E) were determined by IP-coupled conventional PCR and real-time PCR (n = 4).