Studies on the bacteriophage MS2. Some nucleotide sequences from the RNA-polymerase gene

Abstract

The knowledge of the amino acid sequence from the coat protein of the RNA bacteriophages f2, R 17 and MS2 [ l-31 allowed the identification of several RNA fragments as being derived from this gene. They were all obtained by partial ribonuclease hydrolysis of R17 RNA [4-61, f2 RNA [7] or MS2 RNA [8, 91. For MS2, these sequences could be further extended, and the complete sequence of the coat gene was established [lo]. Furthermore, this se- quence was followed by a 36 nucleotides long inter- cistronic region and by the ribosomal binding site of the next gene, the RNA-polymerase. As the amino acid sequences for the two other gene prod- ucts, the A-protein and the viral RNA-polymerase, are not known, no such simple test exists to identify polynucleotides corresponding to the latter two genes. In this communication we present data on three nucleotide fragments derived from the polymerase gene. This conclusion is based on direct overlaps with known sequences [ lo] , on the established gene order for these phages [ 11, 121, and on the mapping of a series of polypurine tracts in two fragments of the RNA molecule [ 131 . 2. Methods All RNA fragments described in this study were *