title: Studies of translational misreading in vivo show that the ribosome very efficiently discriminates against most potential errors.
abstract: Protein synthesis must rapidly and repeatedly discriminate between a single correct and many incorrect aminoacyl-tRNAs. We have attempted to measure the frequencies of all possible missense errors by tRNA , tRNA and tRNA . The most frequent errors involve three types of mismatched nucleotide pairs, U•U, U•C, or U•G, all of which can form a noncanonical base pair with geometry similar to that of the canonical U•A or C•G Watson-Crick pairs. Our system is sensitive enough to measure errors at other potential mismatches that occur at frequencies as low as 1 in 500,000 codons. The ribosome appears to discriminate this efficiently against any pair with non-Watson-Crick geometry. This extreme accuracy may be necessary to allow discrimination against the errors involving near Watson-Crick pairing.
authors.forename: Nandini
authors.initials: N
authors.lastname: Manickam
authors.forename: Nabanita
authors.initials: N
authors.lastname: Nag
authors.forename: Aleeza
authors.initials: A
authors.lastname: Abbasi
authors.forename: Kishan
authors.initials: K
authors.lastname: Patel
authors.forename: Philip J
authors.initials: PJ
authors.lastname: Farabaugh
mesh_terms: D019943:Amino Acid Substitution; D020137:Base Pair Mismatch / Q000502:physiology*; D020029:Base Pairing / Q000502:physiology; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D016296:Mutagenesis / Q000502:physiology; D020125:Mutation, Missense / Q000502:physiology; D009690:Nucleic Acid Conformation; D030781:Organisms, Genetically Modified; D014176:Protein Biosynthesis / Q000502:physiology*; D012349:RNA, Transfer, Asp / Q000378:metabolism; D012352:RNA, Transfer, Glu / Q000378:metabolism; D012365:RNA, Transfer, Tyr / Q000378:metabolism; D012270:Ribosomes / Q000502:physiology*; D001616:beta-Galactosidase / Q000737:chemistry / Q000235:genetics / Q000378:metabolism
chemical_list: D012349:RNA, Transfer, Asp; D012352:RNA, Transfer, Glu; D012365:RNA, Transfer, Tyr; D001616:beta-Galactosidase
keywords: Escherichia coli; mistranslation; non-Watson–Crick base pairs; protein synthesis; β-galactosidase