Deoxyribonucleotide-containing RNAs: a novel class of templates for HIV-1 reverse transcriptase.

Deoxyribonucleotide-containing RNA-like polynucleotides (dcRNAs) were synthesized by mutant T7 RNA polymerase and their structures confirmed by sequencing. dcRNAs annealed with a 20mer oligodeoxyribonucleotide primer were tested as templates/primers in the reverse transcription reaction catalyzed by HIV-1 reverse transcriptase (RT). All dcRNAs were shown to be efficient templates for both wild-type RT and RT mutants, containing 'AZT-resistant' mutations. Differences in the patterns of the DNA products of RNA- and dcRNA-driven reverse transcription were demonstrated. The kinetic characteristics for dcRNAs utilization were compared with the corresponding parameters for RNA/DNA and DNA/DNA templates/primers. The respective K m values for dcRNAs appear to be intermediate between those for RNA and DNA templates. A correlation equation connecting apparent K m value for template/primer and the number of deoxyribonucleotide substitutions in RNA template is proposed.