Reverse transcriptase pauses at N2-methylguanine during in vitro transcription of Escherichia coli 16S ribosomal RNA.

Publisher Website
Google Scholar
Abstract
A restriction fragment complementary to a sequence near the 3'' end of E. coli 16S rRNA was used to prime reverse transcriptase (avian myeloblastosis virus RNA-directed DNA nucleotidyltransferase; deoxynucleosidetriphosphate:DNA deoxynucleotidyltransferase, EC 2.7.7.7). In addition to transcripts that were extended to the 5'' end of the RNA, 2 major transcription intermediates were observed. These discrete-sized c[complementary]DNA intermediates are the result of a kinetic barrier imposed by monomethylation of the amino group on guanine that participates in base-pairing. Both major transcription intermediates correspond to attenuation at the known positions of N2-methylguanine (m2G) in the rRNA sequence. The relaxation time for elongation of the cDNA through m2G is about 3 min. No other major kinetic pauses were observed in the 1340 bases transcribed.