Deoxynucleotide substitution: a new technique for sequence analysis of RNA.

It is possible to replace in a normal transcription reaction catalyzed by E.coli RNA polymerase one of the four precursors by the corresponding deoxynucleoside triphosphate. These deoxynucleotide-substituted RNA's offer interesting prospects for nucleotide sequence analysis. Indeed by the use of U(2)-RNase with dG-RNA, or pancreatic RNase with dC-RNA or dU-RNA, base specific cleavage can be obtained at any of the four residues. In this way overlap of at least six residues in length can be obtained for any site in the RNA. The technique offers also great benefit for solving the sequence of the more difficult T(1)-oligonucleotides. Some examples in the sequence analysis of SV40 DNA-Hind fragments are reported.