HEPADNAVIRUS POLYMERASE HAVING RNA-DEPENDENT DNA PRIMING AND REVERSE TRANSCRIPTASE ACTIVITIES AND METHODS OF MEASURING THESE ACTIVITIES

摘要

An enzymatically active composition of matter, comprising an extracellular combination of a substantially virus-free hepadnavirus polymerase gene product and an RNA template for hepadnavirus minus strand DNA synthesis, is provided. The composition possesses a DNA priming activity and a reverse transcriptase activity. The hepadnavirus polymerase gene product is produced by in vitro expression of a hepadnavirus pol gene. The enzymatically active composition of matter is used in rapid in vitro assays to screen potential anti-hepadnaviral agents. Assays for various functions of the hepadnavirus DNA polymerase are provided, including: (1) binding of the polymerase gene product to hepadnavirus pre-genomic RNA; (2) DNA priming activity of the polymerase gene product; and (3) reverse transcriptase activity of the polymerase gene product.