Publications

• The yeast protein Arc1p binds to tRNA and functions as a cofactor for the methionyl- and glutamyl-tRNA synthetases.

  Simos G., Segref A., Fasiolo F., Hellmuth K., Shevshenko A., Mann M., Hurt E.C.

  Arc1p was found in a screen for components that interact genetically with Los1p, a nuclear pore-associated yeast protein involved in tRNA biogenesis. Arc1p is associated with two proteins which were identified as methionyl-tRNA and glutamyl-tRNA synthetase (MetRS and GluRS) by a new mass spectrome ... >> More

  Arc1p was found in a screen for components that interact genetically with Los1p, a nuclear pore-associated yeast protein involved in tRNA biogenesis. Arc1p is associated with two proteins which were identified as methionyl-tRNA and glutamyl-tRNA synthetase (MetRS and GluRS) by a new mass spectrometry method. ARC1 gene disruption leads to slow growth and reduced MetRS activity, and synthetically lethal arc1-mutants are complemented by the genes for MetRS and GluRS. Recombinant Arc1p binds in vitro to purified monomeric yeast MetRS, but not to an N-terminal truncated form, and strongly increases its apparent affinity for tRNAMet. Furthermore, Arc1p, which is allelic to the quadruplex nucleic acid binding protein G4p1, exhibits specific binding to tRNA as determined by gel retardation and UV-cross-linking. Arc1p is, therefore, a yeast protein with dual specificity: it associates with tRNA and aminoacyl-tRNA synthetases. This functional interaction may be required for efficient aminoacylation in vivo. << Less

  EMBO J. 15:5437-5448(1996) [PubMed] [EuropePMC]

• Striking effects of coupling mutations in the acceptor stem on recognition of tRNAs by Escherichia coli Met-tRNA synthetase and Met-tRNA transformylase.

  Lee C.P., Dyson M.R., Mandal N., Varshney U., Bahramian B., RajBhandary U.L.

  We measured kinetic parameters in vitro and directly analyzed aminoacylation and formylation levels in vivo to study recognition of Escherichia coli initiator tRNA mutants by E. coli Met-tRNA synthetase and Met-tRNA transformylase. We show that, in addition to the anticodon sequence, mutations in ... >> More

  We measured kinetic parameters in vitro and directly analyzed aminoacylation and formylation levels in vivo to study recognition of Escherichia coli initiator tRNA mutants by E. coli Met-tRNA synthetase and Met-tRNA transformylase. We show that, in addition to the anticodon sequence, mutations in the "discriminator" base A73 also affect aminoacylation. An A73----U change has a small effect, but a change to G73 or C73 significantly lowers Vmax/Kappm for in vitro aminoacylation and leads to appreciable accumulation of uncharged tRNA in vivo. Significantly, coupling of the G73 mutation with G72, a neighboring-base mutation, results in a tRNA essentially uncharged in vivo. Coupling of C73 and U73 mutations with G72 does not have such an effect. Elements crucial for Met-tRNA transformylase recognition of tRNAs are located at the end of the acceptor stem. These elements include a weak base pair or a mismatch between nucleotides (nt) 1 and 72 and base pairs 2.71 and 3.70. The natures of nt 1 and 72 are less important than the fact that they do not form a strong Watson-Crick base pair. Interestingly, the negative effect of a C.G base pair between nt 1 and 72 is suppressed by mutation of the neighboring nucleotide A73 to either C73 or U73. The presence of C73 or U73 could destabilize the C1.G72 base pair at the end of an RNA helix. Thus, in some tRNAs, the discriminator base could affect stability of the base pair between nt 1 and 72 and thereby the structure of tRNA at the end of the acceptor stem. << Less

  Proc Natl Acad Sci U S A 89:9262-9266(1992) [PubMed] [EuropePMC]

• Cloning and characterization of the yeast methionyl-tRNA synthetase mutation mes1.

  Chatton B., Winsor B., Boulanger Y., Fasiolo F.

  The chromosomal mes 1 mutation appears to elevate the Km of methionine for yeast methionyl-tRNA synthetase. The mutation was cloned on a multicopy plasmid by gap repair of a plasmid bearing the wild type MES1 gene for a fragment corresponding to the mes 1 mutation. DNA sequencing established that ... >> More

  The chromosomal mes 1 mutation appears to elevate the Km of methionine for yeast methionyl-tRNA synthetase. The mutation was cloned on a multicopy plasmid by gap repair of a plasmid bearing the wild type MES1 gene for a fragment corresponding to the mes 1 mutation. DNA sequencing established that the mutation consists of a single conversion of guanine into adenine which results in the replacement of a glycine by an aspartic acid at position 502. This causes the enzyme to be labile and inactive in vitro and to show a requirement for high concentrations of methionine in vivo. The mutation is in the COOH-terminal domain of the mononucleotide binding fold of the yeast enzyme and suggests participation of this region in the binding of the amino acid residue. << Less

  J. Biol. Chem. 262:15094-15097(1987) [PubMed] [EuropePMC]

• Aminoacyl-tRNA synthesis.

  Ibba M., Soll D.

  Aminoacyl-tRNAs are substrates for translation and are pivotal in determining how the genetic code is interpreted as amino acids. The function of aminoacyl-tRNA synthesis is to precisely match amino acids with tRNAs containing the corresponding anticodon. This is primarily achieved by the direct a ... >> More

  Aminoacyl-tRNAs are substrates for translation and are pivotal in determining how the genetic code is interpreted as amino acids. The function of aminoacyl-tRNA synthesis is to precisely match amino acids with tRNAs containing the corresponding anticodon. This is primarily achieved by the direct attachment of an amino acid to the corresponding tRNA by an aminoacyl-tRNA synthetase, although intrinsic proofreading and extrinsic editing are also essential in several cases. Recent studies of aminoacyl-tRNA synthesis, mainly prompted by the advent of whole genome sequencing and the availability of a vast body of structural data, have led to an expanded and more detailed picture of how aminoacyl-tRNAs are synthesized. This article reviews current knowledge of the biochemical, structural, and evolutionary facets of aminoacyl-tRNA synthesis. << Less

  Annu Rev Biochem 69:617-650(2000) [PubMed] [EuropePMC]

  This publication is cited by 26 other entries.