FIGURE 2.

HBV replication and life-cycle in hepatocytes. Upon infection of hepatocytes, the HBV rcDNA is released into the nucleus and converted into cccDNA, which serves as the template for the transcription of viral pgRNA and mRNAs, including X, S, and C RNAs. The RNA transcripts are transported into the cytoplasm and translated into viral proteins. Subsequently, the pgRNA is encapsidated by viral core and polymerase protein, and reverse transcribed into new viral rcDNA. The DNA-containing virus core particles are either enveloped and secreted as progeny viruses or recycled back to the nucleus to amplify the cccDNA pool (i.e., intracellular amplification). A small portion (5%–10%) of HBV DNA can be linearized and integrated into the host genome during this process, forming a replication-incompetent form that can express viral subunit proteins, such as HBsAg.