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2001
Carnicelli D., Brigotti M., Rizzi S., Keith G., Montanaro L., Sperti S.
Nucleotides U28-A42 and A37 in unmodified yeast tRNA(Trp) as negative identity elements for bovine tryptophanyl-tRNA synthetase Journal Article
In: FEBS Lett, vol. 492, no. 3, pp. 238-41, 2001, (0014-5793 Journal Article).
Abstract | BibTeX | Tags: Acid, Adenine/chemistry, Animals, Base, Cattle, cerevisiae/genetics, Conformation, Data, Fungal/genetics/metabolism, Gov't, Kinetics, Ligase/*metabolism, Molecular, Non-U.S., Nucleic, RNA, Saccharomyces, Sequence, Species, Specificity, Substrate, Support, Transfer, Trp/chemistry/*metabolism, Tryptophan-tRNA, Uridine/chemistry
@article{,
title = {Nucleotides U28-A42 and A37 in unmodified yeast tRNA(Trp) as negative identity elements for bovine tryptophanyl-tRNA synthetase},
author = { D. Carnicelli and M. Brigotti and S. Rizzi and G. Keith and L. Montanaro and S. Sperti},
year = {2001},
date = {2001-01-01},
journal = {FEBS Lett},
volume = {492},
number = {3},
pages = {238-41},
abstract = {Wild-type bovine and yeast tRNA(Trp) are efficiently aminoacylated by tryptophanyl-tRNA synthetase both from beef and from yeast. Upon loss of modified bases in the synthetic transcripts, mammalian tRNA(Trp) retains the double recognition by the two synthetases, while yeast tRNA(Trp) loses its substrate properties for the bovine enzyme and is recognised only by the cognate synthetase. By testing chimeric bovine-yeast transcripts with tryptophanyl-tRNA synthetase purified from beef pancreas, the nucleotides responsible for the loss of charging of the synthetic yeast transcript have been localised in the anticodon arm. A complete loss of charging akin to that observed with the yeast transcript requires substitution in the bovine backbone of G37 in the anticodon loop with yeast A37 and of C28-G42 in the anticodon stem with yeast U28-A42. Since A37 does not prevent aminoacylation of the wild-type yeast tRNA(Trp) by the beef enzyme, a negative combination apparently emerges in the synthetic transcript after unmasking of U28 by loss of pseudourydilation.},
note = {0014-5793
Journal Article},
keywords = {Acid, Adenine/chemistry, Animals, Base, Cattle, cerevisiae/genetics, Conformation, Data, Fungal/genetics/metabolism, Gov't, Kinetics, Ligase/*metabolism, Molecular, Non-U.S., Nucleic, RNA, Saccharomyces, Sequence, Species, Specificity, Substrate, Support, Transfer, Trp/chemistry/*metabolism, Tryptophan-tRNA, Uridine/chemistry},
pubstate = {published},
tppubtype = {article}
}
Wild-type bovine and yeast tRNA(Trp) are efficiently aminoacylated by tryptophanyl-tRNA synthetase both from beef and from yeast. Upon loss of modified bases in the synthetic transcripts, mammalian tRNA(Trp) retains the double recognition by the two synthetases, while yeast tRNA(Trp) loses its substrate properties for the bovine enzyme and is recognised only by the cognate synthetase. By testing chimeric bovine-yeast transcripts with tryptophanyl-tRNA synthetase purified from beef pancreas, the nucleotides responsible for the loss of charging of the synthetic yeast transcript have been localised in the anticodon arm. A complete loss of charging akin to that observed with the yeast transcript requires substitution in the bovine backbone of G37 in the anticodon loop with yeast A37 and of C28-G42 in the anticodon stem with yeast U28-A42. Since A37 does not prevent aminoacylation of the wild-type yeast tRNA(Trp) by the beef enzyme, a negative combination apparently emerges in the synthetic transcript after unmasking of U28 by loss of pseudourydilation.
1992
Wilhelm M. L., Keith G., Fix C., Wilhelm F. X.
Pleiotropic effect of a point mutation in the yeast SUP4-o tRNA gene: in vivo pre-tRNA processing in S. cerevisiae Journal Article
In: Nucleic Acids Res, vol. 20, no. 4, pp. 791-6, 1992, (0305-1048 Journal Article).
Abstract | BibTeX | Tags: Base, Blotting, cerevisiae/*genetics/metabolism, Data, Fungal/*genetics, Fungal/genetics/metabolism, Genes, Introns/genetics, Molecular, Mutation/genetics, Northern, Precursors/*metabolism, RNA, Saccharomyces, Sequence, Suppressor/*genetics, Transfer, Tyr/*genetics/metabolism
@article{,
title = {Pleiotropic effect of a point mutation in the yeast SUP4-o tRNA gene: in vivo pre-tRNA processing in S. cerevisiae},
author = { M. L. Wilhelm and G. Keith and C. Fix and F. X. Wilhelm},
year = {1992},
date = {1992-01-01},
journal = {Nucleic Acids Res},
volume = {20},
number = {4},
pages = {791-6},
abstract = {The expression of mutant tyrosine-inserting ochre suppressor SUP4-o tRNA genes in vivo in S. cerevisiae was examined as a basis for further studies of tRNA transcription and processing. In vivo yeast precursor tRNAs have been identified by filter hybridization and primer extension analysis. We have previously shown that a mutant SUP4-o tRNA gene with a C52----A52 transversion at positive 52 (C52----A52(+IVS) allele) was transcribed but that the primary transcript was not processed correctly. We show here that 5' and 3' end processing as well as splicing are defective for this mutant but that the 5' end processing is restored when the intron is removed from the gene by oligonucleotide directed mutagenesis (C52----A52(-IVS) allele). Our results imply that the C52----A52 transversion by itself cannot account for the lack of susceptibility to RNase P cleavage but that the overall tertiary structure of the mutant tRNA precursor is destabilized by the intron/anticodon stem. A second consequence of the C52----A52 transversion is to prevent complete maturation of the tRNA precursor at its 3' end since intermediates containing incompletely processed 3' trailers accumulate in the yeast cells transformed with the C52----A52(-IVS) allele. A correct structure of the T stem might therefore define a structural feature required for the recognition of the 3' processing activity.},
note = {0305-1048
Journal Article},
keywords = {Base, Blotting, cerevisiae/*genetics/metabolism, Data, Fungal/*genetics, Fungal/genetics/metabolism, Genes, Introns/genetics, Molecular, Mutation/genetics, Northern, Precursors/*metabolism, RNA, Saccharomyces, Sequence, Suppressor/*genetics, Transfer, Tyr/*genetics/metabolism},
pubstate = {published},
tppubtype = {article}
}
The expression of mutant tyrosine-inserting ochre suppressor SUP4-o tRNA genes in vivo in S. cerevisiae was examined as a basis for further studies of tRNA transcription and processing. In vivo yeast precursor tRNAs have been identified by filter hybridization and primer extension analysis. We have previously shown that a mutant SUP4-o tRNA gene with a C52----A52 transversion at positive 52 (C52----A52(+IVS) allele) was transcribed but that the primary transcript was not processed correctly. We show here that 5' and 3' end processing as well as splicing are defective for this mutant but that the 5' end processing is restored when the intron is removed from the gene by oligonucleotide directed mutagenesis (C52----A52(-IVS) allele). Our results imply that the C52----A52 transversion by itself cannot account for the lack of susceptibility to RNase P cleavage but that the overall tertiary structure of the mutant tRNA precursor is destabilized by the intron/anticodon stem. A second consequence of the C52----A52 transversion is to prevent complete maturation of the tRNA precursor at its 3' end since intermediates containing incompletely processed 3' trailers accumulate in the yeast cells transformed with the C52----A52(-IVS) allele. A correct structure of the T stem might therefore define a structural feature required for the recognition of the 3' processing activity.
