Genome-length copies of poliovirion RNA are synthesized in vitro by the poliovirus RNA-dependent RNA polymerase.

摘要: A soluble RNA-dependent RNA polymerase was purified from the cytoplasm of poliovirus-infected HeLa cells. single virus-specific protein designated as p63 (or NCVP4) copurified with this activity. The free ribonuclease activity and shown to copy poliovirion when oligo(U) added in vitro reaction mixture. Characterization product by electrophoresis methylmercury (II) hydroxide-agarose gels showed that genome-sized copies were synthesized polymerase. be heteropolymeric, complementary virion RNA, covalently linked oligo(U). contained expected distribution UMP GMP containing dinucleotide pairs which included a very low frequency CpG pairs. amount, size distribution, rate synthesis dependent on conditions. Full sized about 6 min conditions used yielded maximum elongation rates (pH 8.0, 7 mM Mg2+, 37 degrees C). Under these conditions, most recovered 1-h full sized. Thus, found specifically initiate at 3'-end template using an primer carry out 1250 nucleotides/min resulted RNA.