title: Transfer RNA modifications that alter +1 frameshifting in general fail to affect -1 frameshifting.
abstract: Using mutants (tgt, mnmA(asuE, trmU), mnmE(trmE), miaA, miaB, miaE, truA(hisT), truB) of either Escherichia coli or Salmonella enterica serovar Typhimurium and the trm5 mutant of Saccharomyces cerevisiae, we have analyzed the influence by the modified nucleosides Q34, mnm(5)s(2)U34, ms(2)io(6)A37, Psi39, Psi55, m(1)G37, and yW37 on -1 frameshifts errors at various heptameric sequences, at which at least one codon is decoded by tRNAs having these modified nucleosides. The frequency of -1 frameshifting was the same in congenic strains only differing in the allelic state of the various tRNA modification genes. In fact, in one case (deficiency of mnm(5)s(2)U34), we observed a reduced ability of the undermodified tRNA to make a -1 frameshift error. These results are in sharp contrast to earlier observations that tRNA modification prevents +1 frameshifting suggesting that the mechanisms by which -1 and +1 frameshift errors occur are different. Possible mechanisms explaining these results are discussed.
authors.affiliation: Department of Molecular Biology, Umeå University, SE-90 187 Umeå, Sweden.
authors.forename: Jaunius
authors.initials: J
authors.lastname: Urbonavicius
authors.forename: Guillaume
authors.initials: G
authors.lastname: Stahl
authors.forename: Jérôme M B
authors.initials: JM
authors.lastname: Durand
authors.forename: Samia N
authors.initials: SN
authors.lastname: Ben Salem
authors.forename: Qiang
authors.initials: Q
authors.lastname: Qian
authors.forename: Philip J
authors.initials: PJ
authors.lastname: Farabaugh
authors.forename: Glenn R
authors.initials: GR
authors.lastname: Björk
mesh_terms: D000926:Anticodon; D001483:Base Sequence; D004926:Escherichia coli / Q000235:genetics; D018965:Frameshifting, Ribosomal; D008957:Models, Genetic; D009154:Mutation; D009705:Nucleosides / Q000737:chemistry; D012343:RNA, Transfer / Q000737:chemistry* / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000235:genetics; D012486:Salmonella typhimurium / Q000235:genetics
chemical_list: D000926:Anticodon; D009705:Nucleosides; D012343:RNA, Transfer