title: Nucleotide sequence of the SUF2 frameshift suppressor gene of Saccharomyces cerevisiae.
abstract: To elucidate the molecular mechanism of frameshift suppression by the SUF2 gene of yeast, the sequences of DNA fragments carrying the SUF2-1 and suf2+ alleles of the gene and surrounding regions have been determined. Comparison of the suppressor and wild-type sequences indicates that the SUF2 gene product is a proline tRNA. Disregarding possible base modifications, we find that the wild-type suf2+ anticodon of the tRNA inferred from the DNA sequence is 3'-GGA-5'. The SUF2-1 mutation represents the insertion of a G-C base pair at a position in the gene that corresponds to the anticodon loop of the tRNA. Replacement of the wild-type suf2+ anticodon by a 3'-GGGA-5' fourbase anticodon enables the SUF2-1 tRNA to suppress the 5'-CCCU-3' four-base codons generated as the result of the his4-712 and his4-713 frameshift mutations. This nontriplet codon-anticodon interaction restores the correct reading frame and allows synthesis of a functional his4 protein.
mesh_terms: D001483:Base Sequence; D003062:Codon; D005796:Genes; D009690:Nucleic Acid Conformation; D011392:Proline; D012333:RNA, Messenger / Q000235:genetics; D012343:RNA, Transfer / Q000235:genetics; D012441:Saccharomyces cerevisiae / Q000235:genetics*; D013489:Suppression, Genetic
chemical_list: D003062:Codon; D012333:RNA, Messenger; D012343:RNA, Transfer; D011392:Proline