Initiation of DNA Synthesis by Oligoribonucleotides

Abstract

The known DNA polymerases are unable to initiate the synthesis of new DNA chains without a primer (1). DNA synthesis begins by the addition of nucleotide residues to the 3′-OH terminus of a pre-existing chain which has always been of the deoxy type. Recently, however, it was discovered that oligoribonucleotides also can be used for the priming of DNA synthesis. Verma et al. (2) found that DNA synthesis by reverse transcriptase from avian myeloblastosis virus is initiated by an oligoribonucleotide, and, further, it has been suggested that an oligoribonucleotide might be involved in the initiation of DNA synthesis by Escherichia coli polymerase (3).