Allocation of 15 RNase T1-resistant large oligonucleotides of MS2 RNA.

Four large MS2 RNA fragments with the original 5'-end were obtained by limited RNase T1 digestion. The lengths of the fragments were 36, 30, 22, and 19% of the whole molecule. Whole MS2 RNA and the four fragments were completely digested with RNase T1 and analyzed by the two-dimensional "homochromatography fingerprint" technique. Sixteen oligonucleotides of MS2 RNA were separated and the oligonucleotides were assigned to the fragments. Fifteen of the sixteen oligonucleotides could be classified into three regions of the cistrons of bacteriophage MS2.