Reovirus RNA-directed synthesis of DNA: I. The reaction catalyzed by DNA polymerase from Escherichia coli

Reovirus RNA is an effective template in DNA synthesis catalyzed by DNA polymerase from Escherichia coli B. The product has a base composition similar to that of the reovirus RNA primer and has nearest-neighbor sequence frequencies similar to those in the complementary RNA product of the reovirus RNA-primed RNA polymerase reaction. There is no evidence of deoxyribonucleotide homo-polymer synthesis in the DNA polymerase reaction. The DNA product collected after 30 minutes of incubation is largely double-stranded and maintains a denatured state after heating and rapid cooling. It has not yet been established whether there is first formed on the RNA template a single-stranded DNA, which on liberation from the double-stranded RNA template is preferentially copied to produce a fully denaturable double-stranded DNA, or whether the product formed on the double-stranded RNA template is initially double-stranded DNA. As is the case in DNA-primed reactions, actinomycin D inhibits reovirus RNA-primed incorporation of deoxyribonucleotides into DNA with DNA polymerase as enzyme to a lesser extent than the reovirus RNA-primed incorporation of ribonucleotides into RNA with RNA polymerase as enzyme. With ribonucleoside triphosphates as precursors, there is little or no RNA synthesis in the reovirus RNA-primed DNA polymerase reaction.