Life cycle and genomic organization of HBV. (a) The enveloped infectious HBV particle is uncoated after infection releasing the capsid (1) that migrates to the cell nucleus where it delivers the genomic rcDNA (2) which is converted into cccDNA (3), the template for transcription of the viral RNAs. (b) Physical map of HBV with the four open-reading frames and viral RNAs. Also indicated are the positions of enhancers I and II (EN1, EN2). For additional details, see ref. 5.