SPECIFIC HEPATITIS-B VIRUS MINUS-STRAND DNA-SYNTHESIS REQUIRES ONLY THE 5'-ENCAPSIDATION SIGNAL AND THE 3'-PROXIMAL DIRECT REPEAT DR1-ASTERISK

Human hepatitis B virus (HBV) is a small DNA virus that replicates ins ide the viral nucleocapsid by reverse transcription of an RNA intermed iate, the pregenome. The sequences encompassing the encapsidation sign al epsilon and the direct repeat DR1 are present in two copies on this terminally redundant transcript. We have recently shown that HBV minu s-strand DNA synthesis involves transfer of a short DNA primer copied from 5'-epsilon to 3'-DR1 (DR1). Using transfection of HBV genomes wi th lesions in 3'-epsilon, and 5'-DR1 and its preceding sequence, we te sted whether these additional elements contribute to the specificity o f the transfer reaction, However, while some mutations affected proper plus-strand DNA formation, 5'-epsilon and DR1 were completely suffic ient for correct minus-strand DNA production.