Methylated nucleotide sequences in HeLa-cell ribosomal ribonucleic acid. Correlation between the results from ‘fingerprinting’ hydrolysates obtained by digestion with T1 ribonuclease and with T1 plus pancreatic ribonuclease

The methylated nucleotide sequences in HeLa-cell rRNA were previously characterized after enzymic digestion of the rRNA by T1 ribonuclease alone or by combined T1 plus pancreatic ribonucleases. For any methylated product occurring in a T1-ribonuclease digest there must be one or more corresponding products in a combined T1-plus-pancreatic-ribonuclease digest. Here we correlate fully the inter-relationship between the methylated products occurring in the two digestion systems. The analysis has led to the resolution of some previous uncertainties and has permitted an almost complete qualitative and quantitative description of the methylated components in HeLa-cell rRNA. The data are compared with those reported by other authors for HeLa-cell rRNA.