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2008
Geary C., Baudrey S., Jaeger L.
Comprehensive features of natural and in vitro selected GNRA tetraloop-binding receptors Journal Article
In: Nucleic Acids Res, vol. 36, no. 4, pp. 1138-52, 2008, (1362-4962 (Electronic) Journal Article Research Support, N.I.H., Extramural Research Support, U.S. Gov't, Non-P.H.S.).
Abstract | BibTeX | Tags: Acid, Adenine/chemistry, Analysis, Base, Conformation, Data, dimerization, directed, Evolution, KROL, Models, Molecular, Nucleic, RNA, RNA/*chemistry/classification, Sequence, Thermodynamics
@article{,
title = {Comprehensive features of natural and in vitro selected GNRA tetraloop-binding receptors},
author = { C. Geary and S. Baudrey and L. Jaeger},
year = {2008},
date = {2008-01-01},
journal = {Nucleic Acids Res},
volume = {36},
number = {4},
pages = {1138-52},
abstract = {Specific recognitions of GNRA tetraloops by small helical receptors are among the most widespread long-range packing interactions in large ribozymes. However, in contrast to GYRA and GAAA tetraloops, very few GNRA/receptor interactions have yet been identified to involve GGAA tetraloops in nature. A novel in vitro selection scheme based on a rigid self-assembling tectoRNA scaffold designed for isolation of intermolecular interactions with A-minor motifs has yielded new GGAA tetraloop-binding receptors with affinity in the nanomolar range. One of the selected receptors is a novel 12 nt RNA motif, (CCUGUG. AUCUGG), that recognizes GGAA tetraloop hairpin with a remarkable specificity and affinity. Its physical and chemical characteristics are comparable to those of the well-studied '11nt' GAAA tetraloop receptor motif. A second less specific motif (CCCAGCCC. GAUAGGG) binds GGRA tetraloops and appears to be related to group IC3 tetraloop receptors. Mutational, thermodynamic and comparative structural analysis suggests that natural and in vitro selected GNRA receptors can essentially be grouped in two major classes of GNRA binders. New insights about the evolution, recognition and structural modularity of GNRA and A-minor RNA-RNA interactions are proposed.},
note = {1362-4962 (Electronic)
Journal Article
Research Support, N.I.H., Extramural
Research Support, U.S. Gov't, Non-P.H.S.},
keywords = {Acid, Adenine/chemistry, Analysis, Base, Conformation, Data, dimerization, directed, Evolution, KROL, Models, Molecular, Nucleic, RNA, RNA/*chemistry/classification, Sequence, Thermodynamics},
pubstate = {published},
tppubtype = {article}
}
Specific recognitions of GNRA tetraloops by small helical receptors are among the most widespread long-range packing interactions in large ribozymes. However, in contrast to GYRA and GAAA tetraloops, very few GNRA/receptor interactions have yet been identified to involve GGAA tetraloops in nature. A novel in vitro selection scheme based on a rigid self-assembling tectoRNA scaffold designed for isolation of intermolecular interactions with A-minor motifs has yielded new GGAA tetraloop-binding receptors with affinity in the nanomolar range. One of the selected receptors is a novel 12 nt RNA motif, (CCUGUG. AUCUGG), that recognizes GGAA tetraloop hairpin with a remarkable specificity and affinity. Its physical and chemical characteristics are comparable to those of the well-studied '11nt' GAAA tetraloop receptor motif. A second less specific motif (CCCAGCCC. GAUAGGG) binds GGRA tetraloops and appears to be related to group IC3 tetraloop receptors. Mutational, thermodynamic and comparative structural analysis suggests that natural and in vitro selected GNRA receptors can essentially be grouped in two major classes of GNRA binders. New insights about the evolution, recognition and structural modularity of GNRA and A-minor RNA-RNA interactions are proposed.
2004
Martineau Y., Bec C. Le, Monbrun L., Allo V., Chiu I. M., Danos O., Moine H., Prats H., Prats A. C.
Internal ribosome entry site structural motifs conserved among mammalian fibroblast growth factor 1 alternatively spliced mRNAs Journal Article
In: Mol Cell Biol, vol. 24, no. 17, pp. 7622-35, 2004, (0270-7306 Journal Article).
Abstract | BibTeX | Tags: (Genetics), *5', *Alternative, *Nucleic, *Promoter, 1/*genetics, Acid, Alignment, Animals, Base, Cell, Conformation, Data, EHRESMANN, Factor, Fibroblast, Gene, Genes, Genetic, Gov't, Growth, Human, Line, Messenger/chemistry/*genetics/metabolism, Mice, Molecular, Muscle, Mutagenesis, Non-U.S., Regions, Ribosomes/*metabolism, RNA, Sequence, Site-Directed, Skeletal/cytology/physiology, Splicing, Structural/genetics, Support, Techniques, Transfer, Untranslated, Vectors
@article{,
title = {Internal ribosome entry site structural motifs conserved among mammalian fibroblast growth factor 1 alternatively spliced mRNAs},
author = { Y. Martineau and C. Le Bec and L. Monbrun and V. Allo and I. M. Chiu and O. Danos and H. Moine and H. Prats and A. C. Prats},
year = {2004},
date = {2004-01-01},
journal = {Mol Cell Biol},
volume = {24},
number = {17},
pages = {7622-35},
abstract = {Fibroblast growth factor 1 (FGF-1) is a powerful angiogenic factor whose gene structure contains four promoters, giving rise to a process of alternative splicing resulting in four mRNAs with alternative 5' untranslated regions (5' UTRs). Here we have identified, by using double luciferase bicistronic vectors, the presence of internal ribosome entry sites (IRESs) in the human FGF-1 5' UTRs, particularly in leaders A and C, with distinct activities in mammalian cells. DNA electrotransfer in mouse muscle revealed that the IRES present in the FGF-1 leader A has a high activity in vivo. We have developed a new regulatable TET OFF bicistronic system, which allowed us to rule out the possibility of any cryptic promoter in the FGF-1 leaders. FGF-1 IRESs A and C, which were mapped in fragments of 118 and 103 nucleotides, respectively, are flexible in regard to the position of the initiation codon, making them interesting from a biotechnological point of view. Furthermore, we show that FGF-1 IRESs A of murine and human origins show similar IRES activity profiles. Enzymatic and chemical probing of the FGF-1 IRES A RNA revealed a structural domain conserved among mammals at both the nucleotide sequence and RNA structure levels. The functional role of this structural motif has been demonstrated by point mutagenesis, including compensatory mutations. These data favor an important role of IRESs in the control of FGF-1 expression and provide a new IRES structural motif that could help IRES prediction in 5' UTR databases.},
note = {0270-7306
Journal Article},
keywords = {(Genetics), *5', *Alternative, *Nucleic, *Promoter, 1/*genetics, Acid, Alignment, Animals, Base, Cell, Conformation, Data, EHRESMANN, Factor, Fibroblast, Gene, Genes, Genetic, Gov't, Growth, Human, Line, Messenger/chemistry/*genetics/metabolism, Mice, Molecular, Muscle, Mutagenesis, Non-U.S., Regions, Ribosomes/*metabolism, RNA, Sequence, Site-Directed, Skeletal/cytology/physiology, Splicing, Structural/genetics, Support, Techniques, Transfer, Untranslated, Vectors},
pubstate = {published},
tppubtype = {article}
}
Fibroblast growth factor 1 (FGF-1) is a powerful angiogenic factor whose gene structure contains four promoters, giving rise to a process of alternative splicing resulting in four mRNAs with alternative 5' untranslated regions (5' UTRs). Here we have identified, by using double luciferase bicistronic vectors, the presence of internal ribosome entry sites (IRESs) in the human FGF-1 5' UTRs, particularly in leaders A and C, with distinct activities in mammalian cells. DNA electrotransfer in mouse muscle revealed that the IRES present in the FGF-1 leader A has a high activity in vivo. We have developed a new regulatable TET OFF bicistronic system, which allowed us to rule out the possibility of any cryptic promoter in the FGF-1 leaders. FGF-1 IRESs A and C, which were mapped in fragments of 118 and 103 nucleotides, respectively, are flexible in regard to the position of the initiation codon, making them interesting from a biotechnological point of view. Furthermore, we show that FGF-1 IRESs A of murine and human origins show similar IRES activity profiles. Enzymatic and chemical probing of the FGF-1 IRES A RNA revealed a structural domain conserved among mammals at both the nucleotide sequence and RNA structure levels. The functional role of this structural motif has been demonstrated by point mutagenesis, including compensatory mutations. These data favor an important role of IRESs in the control of FGF-1 expression and provide a new IRES structural motif that could help IRES prediction in 5' UTR databases.
Przykorska A., Solecka K., Olszak K., Keith G., Nawrot B., Kuligowska E.
Wheat (Triticum vulgare) chloroplast nuclease ChSI exhibits 5' flap structure-specific endonuclease activity Journal Article
In: Biochemistry, vol. 43, no. 35, pp. 11283-94, 2004, (0006-2960 Journal Article).
Abstract | BibTeX | Tags: &, Acid, Catalysis, Chloroplasts/*enzymology, Conformation, Desorption-Ionization, DNA, Endonucleases/*chemistry/isolation, Exonucleases/chemistry/metabolism, Flap, Gov't, Hydrolysis, KEITH, Kinetics, Laser, Mass, Matrix-Assisted, Non-U.S., Nucleic, Oligonucleotides/chemical, Plant/chemistry/metabolism, purification/*metabolism, Relationship, Single-Stranded/chemistry/metabolism, Specificity, Spectrometry, Structure-Activity, Substrate, Support, synthesis/metabolism, Thermodynamics, Triticum/*enzymology
@article{,
title = {Wheat (Triticum vulgare) chloroplast nuclease ChSI exhibits 5' flap structure-specific endonuclease activity},
author = { A. Przykorska and K. Solecka and K. Olszak and G. Keith and B. Nawrot and E. Kuligowska},
year = {2004},
date = {2004-01-01},
journal = {Biochemistry},
volume = {43},
number = {35},
pages = {11283-94},
abstract = {The structure-specific ChSI nuclease from wheat (Triticum vulgare) chloroplast stroma has been previously purified and characterized in our laboratory. It is a single-strand-specific DNA and RNA endonuclease. Although the enzyme has been initially characterized and used as a structural probe, its biological function is still unknown. Localization of the ChSI enzyme inside chloroplasts, possessing their own DNA that is generally highly exposed to UV light and often affected by numerous redox reactions and electron transfer processes, might suggest, however, that this enzyme could be involved in DNA repair. The repair of some types of DNA damage has been shown to proceed through branched DNA intermediates which are substrates for the structure-specific DNA endonucleases. Thus we tested the substrate specificity of ChSI endonuclease toward various branched DNAs containing 5' flap, 5' pseudoflap, 3' pseudoflap, or single-stranded bulged structural motifs. It appears that ChSI has a high 5' flap structure-specific endonucleolytic activity. The catalytic efficiency (k(cat)/K(M)) of the enzyme is significantly higher for the 5' flap substrate than for single-stranded DNA. The ChSI 5' flap activity was inhibited by high concentrations of Mg(2+), Mn(2+), Zn(2+), or Ca(2+). However, low concentrations of divalent cations could restore the loss of ChSI activity as a consequence of EDTA pretreatment. In contrast to other known 5' flap nucleases, the chloroplast enzyme ChSI does not possess any 5'-->3' exonuclease activity on double-stranded DNA. Therefore, we conclude that ChSI is a 5' flap structure-specific endonuclease with nucleolytic activity toward single-stranded substrates.},
note = {0006-2960
Journal Article},
keywords = {&, Acid, Catalysis, Chloroplasts/*enzymology, Conformation, Desorption-Ionization, DNA, Endonucleases/*chemistry/isolation, Exonucleases/chemistry/metabolism, Flap, Gov't, Hydrolysis, KEITH, Kinetics, Laser, Mass, Matrix-Assisted, Non-U.S., Nucleic, Oligonucleotides/chemical, Plant/chemistry/metabolism, purification/*metabolism, Relationship, Single-Stranded/chemistry/metabolism, Specificity, Spectrometry, Structure-Activity, Substrate, Support, synthesis/metabolism, Thermodynamics, Triticum/*enzymology},
pubstate = {published},
tppubtype = {article}
}
The structure-specific ChSI nuclease from wheat (Triticum vulgare) chloroplast stroma has been previously purified and characterized in our laboratory. It is a single-strand-specific DNA and RNA endonuclease. Although the enzyme has been initially characterized and used as a structural probe, its biological function is still unknown. Localization of the ChSI enzyme inside chloroplasts, possessing their own DNA that is generally highly exposed to UV light and often affected by numerous redox reactions and electron transfer processes, might suggest, however, that this enzyme could be involved in DNA repair. The repair of some types of DNA damage has been shown to proceed through branched DNA intermediates which are substrates for the structure-specific DNA endonucleases. Thus we tested the substrate specificity of ChSI endonuclease toward various branched DNAs containing 5' flap, 5' pseudoflap, 3' pseudoflap, or single-stranded bulged structural motifs. It appears that ChSI has a high 5' flap structure-specific endonucleolytic activity. The catalytic efficiency (k(cat)/K(M)) of the enzyme is significantly higher for the 5' flap substrate than for single-stranded DNA. The ChSI 5' flap activity was inhibited by high concentrations of Mg(2+), Mn(2+), Zn(2+), or Ca(2+). However, low concentrations of divalent cations could restore the loss of ChSI activity as a consequence of EDTA pretreatment. In contrast to other known 5' flap nucleases, the chloroplast enzyme ChSI does not possess any 5'-->3' exonuclease activity on double-stranded DNA. Therefore, we conclude that ChSI is a 5' flap structure-specific endonuclease with nucleolytic activity toward single-stranded substrates.
2003
Bonnal S., Schaeffer C., Creancier L., Clamens S., Moine H., Prats A. C., Vagner S.
A single internal ribosome entry site containing a G quartet RNA structure drives fibroblast growth factor 2 gene expression at four alternative translation initiation codons Journal Article
In: J Biol Chem, vol. 278, no. 41, pp. 39330-6, 2003, (0021-9258 Journal Article).
Abstract | BibTeX | Tags: 2/*genetics, Acid, Alternative, Base, Cell, Chain, Codon, Complementary/genetics, Conformation, Data, Deletion, DNA, Expression, Factor, Fibroblast, Gene, Gov't, Growth, Human, initiation, Initiator/genetics, Line, Messenger/*chemistry/*genetics, Molecular, Non-U.S., Nucleic, Peptide, Ribosomes/*metabolism, RNA, Sequence, Splicing, Support, Transfection
@article{,
title = {A single internal ribosome entry site containing a G quartet RNA structure drives fibroblast growth factor 2 gene expression at four alternative translation initiation codons},
author = { S. Bonnal and C. Schaeffer and L. Creancier and S. Clamens and H. Moine and A. C. Prats and S. Vagner},
year = {2003},
date = {2003-01-01},
journal = {J Biol Chem},
volume = {278},
number = {41},
pages = {39330-6},
abstract = {The 484-nucleotide (nt) alternatively translated region (ATR) of the human fibroblast growth factor 2 (FGF-2) mRNA contains four CUG and one AUG translation initiation codons. Although the 5'-end proximal CUG codon is initiated by a cap-dependent translation process, the other four initiation codons are initiated by a mechanism of internal entry of ribosomes. We undertook here a detailed analysis of the cis-acting elements defining the FGF-2 internal ribosome entry site (IRES). A thorough deletion analysis study within the 5'-ATR led us to define a 176-nt region as being necessary and sufficient for IRES function at four codons present in a downstream 308-nt RNA segment. Unexpectedly, a single IRES module is therefore responsible for translation initiation at four distantly localized codons. The determination of the FGF-2 5'-ATR RNA secondary structure by enzymatic and chemical probing experiments showed that the FGF-2 IRES contained two stem-loop regions and a G quartet motif that constitute novel structural determinants of IRES function.},
note = {0021-9258
Journal Article},
keywords = {2/*genetics, Acid, Alternative, Base, Cell, Chain, Codon, Complementary/genetics, Conformation, Data, Deletion, DNA, Expression, Factor, Fibroblast, Gene, Gov't, Growth, Human, initiation, Initiator/genetics, Line, Messenger/*chemistry/*genetics, Molecular, Non-U.S., Nucleic, Peptide, Ribosomes/*metabolism, RNA, Sequence, Splicing, Support, Transfection},
pubstate = {published},
tppubtype = {article}
}
The 484-nucleotide (nt) alternatively translated region (ATR) of the human fibroblast growth factor 2 (FGF-2) mRNA contains four CUG and one AUG translation initiation codons. Although the 5'-end proximal CUG codon is initiated by a cap-dependent translation process, the other four initiation codons are initiated by a mechanism of internal entry of ribosomes. We undertook here a detailed analysis of the cis-acting elements defining the FGF-2 internal ribosome entry site (IRES). A thorough deletion analysis study within the 5'-ATR led us to define a 176-nt region as being necessary and sufficient for IRES function at four codons present in a downstream 308-nt RNA segment. Unexpectedly, a single IRES module is therefore responsible for translation initiation at four distantly localized codons. The determination of the FGF-2 5'-ATR RNA secondary structure by enzymatic and chemical probing experiments showed that the FGF-2 IRES contained two stem-loop regions and a G quartet motif that constitute novel structural determinants of IRES function.
2002
Cristofari G., Bampi C., Wilhelm M., Wilhelm F. X., Darlix J. L.
A 5'-3' long-range interaction in Ty1 RNA controls its reverse transcription and retrotransposition Journal Article
In: EMBO J, vol. 21, no. 16, pp. 4368-79, 2002, (0261-4189 Journal Article).
Abstract | BibTeX | Tags: *Gene, *Transcription, Acid, cerevisiae/*genetics, Complementary/biosynthesis, Conformation, DNA, Expression, Fungal, Fungal/chemistry/*metabolism, Genetic, Gov't, in, Messenger/chemistry/*metabolism, Non-U.S., Nucleic, Phylogeny, Regulation, Retroelements/*genetics, RNA, Saccharomyces, Support, vitro
@article{,
title = {A 5'-3' long-range interaction in Ty1 RNA controls its reverse transcription and retrotransposition},
author = { G. Cristofari and C. Bampi and M. Wilhelm and F. X. Wilhelm and J. L. Darlix},
year = {2002},
date = {2002-01-01},
journal = {EMBO J},
volume = {21},
number = {16},
pages = {4368-79},
abstract = {LTR-retrotransposons are abundant components of all eukaryotic genomes and appear to be key players in their evolution. They share with retroviruses a reverse transcription step during their replication cycle. To better understand the replication of retrotransposons as well as their similarities to and differences from retroviruses, we set up an in vitro model system to examine minus-strand cDNA synthesis of the yeast Ty1 LTR-retrotransposon. Results show that the 5' and 3' ends of Ty1 genomic RNA interact through 14 nucleotide 5'-3' complementary sequences (CYC sequences). This 5'-3' base pairing results in an efficient initiation of reverse transcription in vitro. Transposition of a marked Ty1 element and Ty1 cDNA synthesis in yeast rely on the ability of the CYC sequences to base pair. This 5'-3' interaction is also supported by phylogenic analysis of all full-length Ty1 and Ty2 elements present in the Saccharomyces cerevisiae genome. These novel findings lead us to propose that circularization of the Ty1 genomic RNA controls initiation of reverse transcription and may limit reverse transcription of defective retroelements.},
note = {0261-4189
Journal Article},
keywords = {*Gene, *Transcription, Acid, cerevisiae/*genetics, Complementary/biosynthesis, Conformation, DNA, Expression, Fungal, Fungal/chemistry/*metabolism, Genetic, Gov't, in, Messenger/chemistry/*metabolism, Non-U.S., Nucleic, Phylogeny, Regulation, Retroelements/*genetics, RNA, Saccharomyces, Support, vitro},
pubstate = {published},
tppubtype = {article}
}
LTR-retrotransposons are abundant components of all eukaryotic genomes and appear to be key players in their evolution. They share with retroviruses a reverse transcription step during their replication cycle. To better understand the replication of retrotransposons as well as their similarities to and differences from retroviruses, we set up an in vitro model system to examine minus-strand cDNA synthesis of the yeast Ty1 LTR-retrotransposon. Results show that the 5' and 3' ends of Ty1 genomic RNA interact through 14 nucleotide 5'-3' complementary sequences (CYC sequences). This 5'-3' base pairing results in an efficient initiation of reverse transcription in vitro. Transposition of a marked Ty1 element and Ty1 cDNA synthesis in yeast rely on the ability of the CYC sequences to base pair. This 5'-3' interaction is also supported by phylogenic analysis of all full-length Ty1 and Ty2 elements present in the Saccharomyces cerevisiae genome. These novel findings lead us to propose that circularization of the Ty1 genomic RNA controls initiation of reverse transcription and may limit reverse transcription of defective retroelements.
Perederina A., Nevskaya N., Nikonov O., Nikulin A., Dumas P., Yao M., Tanaka I., Garber M., Gongadze G., Nikonov S.
Detailed analysis of RNA-protein interactions within the bacterial ribosomal protein L5/5S rRNA complex Journal Article
In: RNA, vol. 8, no. 12, pp. 1548-57, 2002, (1355-8382 Journal Article).
Abstract | BibTeX | Tags: 5S/*chemistry/*metabolism, Acid, Amino, Bacterial, Base, Binding, Bonding, coli/genetics, Conformation, Data, Escherichia, Fragments/chemistry/metabolism, Gov't, Hydrogen, Models, Molecular, Non-U.S., Nucleic, Peptide, Protein, Proteins/*chemistry/*metabolism, Proteins/chemistry/metabolism, Ribosomal, RNA, Sequence, Sites, Support
@article{,
title = {Detailed analysis of RNA-protein interactions within the bacterial ribosomal protein L5/5S rRNA complex},
author = { A. Perederina and N. Nevskaya and O. Nikonov and A. Nikulin and P. Dumas and M. Yao and I. Tanaka and M. Garber and G. Gongadze and S. Nikonov},
year = {2002},
date = {2002-01-01},
journal = {RNA},
volume = {8},
number = {12},
pages = {1548-57},
abstract = {The crystal structure of ribosomal protein L5 from Thermus thermophilus complexed with a 34-nt fragment comprising helix III and loop C of Escherichia coli 5S rRNA has been determined at 2.5 A resolution. The protein specifically interacts with the bulged nucleotides at the top of loop C of 5S rRNA. The rRNA and protein contact surfaces are strongly stabilized by intramolecular interactions. Charged and polar atoms forming the network of conserved intermolecular hydrogen bonds are located in two narrow planar parallel layers belonging to the protein and rRNA, respectively. The regions, including these atoms conserved in Bacteria and Archaea, can be considered an RNA-protein recognition module. Comparison of the T. thermophilus L5 structure in the RNA-bound form with the isolated Bacillus stearothermophilus L5 structure shows that the RNA-recognition module on the protein surface does not undergo significant changes upon RNA binding. In the crystal of the complex, the protein interacts with another RNA molecule in the asymmetric unit through the beta-sheet concave surface. This protein/RNA interface simulates the interaction of L5 with 23S rRNA observed in the Haloarcula marismortui 50S ribosomal subunit.},
note = {1355-8382
Journal Article},
keywords = {5S/*chemistry/*metabolism, Acid, Amino, Bacterial, Base, Binding, Bonding, coli/genetics, Conformation, Data, Escherichia, Fragments/chemistry/metabolism, Gov't, Hydrogen, Models, Molecular, Non-U.S., Nucleic, Peptide, Protein, Proteins/*chemistry/*metabolism, Proteins/chemistry/metabolism, Ribosomal, RNA, Sequence, Sites, Support},
pubstate = {published},
tppubtype = {article}
}
The crystal structure of ribosomal protein L5 from Thermus thermophilus complexed with a 34-nt fragment comprising helix III and loop C of Escherichia coli 5S rRNA has been determined at 2.5 A resolution. The protein specifically interacts with the bulged nucleotides at the top of loop C of 5S rRNA. The rRNA and protein contact surfaces are strongly stabilized by intramolecular interactions. Charged and polar atoms forming the network of conserved intermolecular hydrogen bonds are located in two narrow planar parallel layers belonging to the protein and rRNA, respectively. The regions, including these atoms conserved in Bacteria and Archaea, can be considered an RNA-protein recognition module. Comparison of the T. thermophilus L5 structure in the RNA-bound form with the isolated Bacillus stearothermophilus L5 structure shows that the RNA-recognition module on the protein surface does not undergo significant changes upon RNA binding. In the crystal of the complex, the protein interacts with another RNA molecule in the asymmetric unit through the beta-sheet concave surface. This protein/RNA interface simulates the interaction of L5 with 23S rRNA observed in the Haloarcula marismortui 50S ribosomal subunit.
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.
Moine H., Mandel J. L.
Biomedicine. Do G quartets orchestrate fragile X pathology? Journal Article
In: Science, vol. 294, no. 5551, pp. 2487-8, 2001, (0036-8075 Journal Article).
BibTeX | Tags: Acid, Analysis, Animals, Array, Binding, Brain/metabolism, Conformation, Crystallography, Expression, Fragile, Gene, Genetic, Human, Messenger/*chemistry/genetics/*metabolism, Mice, Nerve, Nucleic, Oligonucleotide, Protein, Proteins/chemistry/genetics/*metabolism, Regions, Regulation, RNA, Sequence, Sites, structure, Synapses/physiology, Syndrome/genetics/*metabolism, Tertiary, Tissue, Translation, Untranslated, X, X-Ray
@article{,
title = {Biomedicine. Do G quartets orchestrate fragile X pathology?},
author = { H. Moine and J. L. Mandel},
year = {2001},
date = {2001-01-01},
journal = {Science},
volume = {294},
number = {5551},
pages = {2487-8},
note = {0036-8075
Journal Article},
keywords = {Acid, Analysis, Animals, Array, Binding, Brain/metabolism, Conformation, Crystallography, Expression, Fragile, Gene, Genetic, Human, Messenger/*chemistry/genetics/*metabolism, Mice, Nerve, Nucleic, Oligonucleotide, Protein, Proteins/chemistry/genetics/*metabolism, Regions, Regulation, RNA, Sequence, Sites, structure, Synapses/physiology, Syndrome/genetics/*metabolism, Tertiary, Tissue, Translation, Untranslated, X, X-Ray},
pubstate = {published},
tppubtype = {article}
}
Wilhelm M., Wilhelm F. X.
Reverse transcription of retroviruses and LTR retrotransposons Journal Article
In: Cell Mol Life Sci, vol. 58, no. 9, pp. 1246-62, 2001, (1420-682x Journal Article Review Review, Academic).
Abstract | BibTeX | Tags: *Retroelements, *Terminal, Acid, Alignment, Amino, Animals, Base, Conformation, Data, DNA, Homology, Human, Molecular, Nucleic, Polymerase/*chemistry/*metabolism, Repeat, Retroviridae/*enzymology/*genetics, RNA-Directed, Sequence, Sequences
@article{,
title = {Reverse transcription of retroviruses and LTR retrotransposons},
author = { M. Wilhelm and F. X. Wilhelm},
year = {2001},
date = {2001-01-01},
journal = {Cell Mol Life Sci},
volume = {58},
number = {9},
pages = {1246-62},
abstract = {Retroelements are mobile genetic entities that replicate via reverse transcription of a template RNA. A key component to the life cycle of these elements is the enzyme reverse transcriptase (RT), which copies the single-stranded genomic RNA of the element into a linear double-stranded DNA that is ultimately integrated into the host genome by the element-encoded integrase. RT is a multifunctionnal enzyme which possesses RNA-dependent and DNA-dependent DNA polymerase activities as well as RNase H activity that specifically degrades the RNA strand of RNA-DNA duplexes. At some stages of the replication a strand-displacement activity of RT is also necessary. All activities are essential for the conversion of single-stranded genomic RNA into the double-stranded preintegrative DNA. This review focuses on the role of RT in the different steps of the replication process of retroelements. The features of retrotransposon replication which differ from the retroviral ones will be emphasized. In a second part of the review, the biochemical and enzymatic properties of two newly characterized retrotransposon RTs will be described. The role of the integrase domain in reverse transcriptase activity of some retroviral and retrotransposon RTs will be discussed.},
note = {1420-682x
Journal Article
Review
Review, Academic},
keywords = {*Retroelements, *Terminal, Acid, Alignment, Amino, Animals, Base, Conformation, Data, DNA, Homology, Human, Molecular, Nucleic, Polymerase/*chemistry/*metabolism, Repeat, Retroviridae/*enzymology/*genetics, RNA-Directed, Sequence, Sequences},
pubstate = {published},
tppubtype = {article}
}
Retroelements are mobile genetic entities that replicate via reverse transcription of a template RNA. A key component to the life cycle of these elements is the enzyme reverse transcriptase (RT), which copies the single-stranded genomic RNA of the element into a linear double-stranded DNA that is ultimately integrated into the host genome by the element-encoded integrase. RT is a multifunctionnal enzyme which possesses RNA-dependent and DNA-dependent DNA polymerase activities as well as RNase H activity that specifically degrades the RNA strand of RNA-DNA duplexes. At some stages of the replication a strand-displacement activity of RT is also necessary. All activities are essential for the conversion of single-stranded genomic RNA into the double-stranded preintegrative DNA. This review focuses on the role of RT in the different steps of the replication process of retroelements. The features of retrotransposon replication which differ from the retroviral ones will be emphasized. In a second part of the review, the biochemical and enzymatic properties of two newly characterized retrotransposon RTs will be described. The role of the integrase domain in reverse transcriptase activity of some retroviral and retrotransposon RTs will be discussed.
1999
Auxilien S., Keith G., Grice S. F. Le, Darlix J. L.
Role of post-transcriptional modifications of primer tRNALys,3 in the fidelity and efficacy of plus strand DNA transfer during HIV-1 reverse transcription Journal Article
In: J Biol Chem, vol. 274, no. 7, pp. 4412-20, 1999, (0021-9258 Journal Article).
Abstract | BibTeX | Tags: *RNA, *Transcription, Acid, Base, Calf, Conformation, Data, DNA, Genetic, Gov't, H, HIV-1, HIV-1/*physiology, Lys/*metabolism, Molecular, Non-U.S., Nucleic, post-transcriptional, Processing, Reverse, Ribonuclease, RNA, Sequence, Support, Templates, Thymus/metabolism, Transcriptase/metabolism, Transfer, Viral/*metabolism, Viral/metabolism
@article{,
title = {Role of post-transcriptional modifications of primer tRNALys,3 in the fidelity and efficacy of plus strand DNA transfer during HIV-1 reverse transcription},
author = { S. Auxilien and G. Keith and S. F. Le Grice and J. L. Darlix},
year = {1999},
date = {1999-01-01},
journal = {J Biol Chem},
volume = {274},
number = {7},
pages = {4412-20},
abstract = {During HIV reverse transcription, (+) strand DNA synthesis is primed by an RNase H-resistant sequence, the polypurine tract, and continues as far as a 18-nt double-stranded RNA region corresponding to the 3' end of tRNALys,3 hybridized to the viral primer binding site (PBS). Before (+) strand DNA transfer, reverse transcriptase (RT) needs to unwind the double-stranded tRNA-PBS RNA in order to reverse-transcribe the 3' end of primer tRNALys,3. Since the detailed mechanism of (+) strand DNA transfer remains incompletely understood, we developed an in vitro system to closely examine this mechanism, composed of HIV 5' RNA, natural modified tRNALys,3, synthetic unmodified tRNALys,3 or oligonucleotides (RNA or DNA) complementary to the PBS, as well as the viral proteins RT and nucleocapsid protein (NCp7). Prior to (+) strand DNA transfer, RT stalls at the double-stranded tRNA-PBS RNA complex and is able to reverse-transcribe modified nucleosides of natural tRNALys,3. Modified nucleoside m1A-58 of natural tRNALys,3 is only partially effective as a stop signal, as RT can transcribe as far as the hyper-modified adenosine (ms2t6A-37) in the anticodon loop. m1A-58 is almost always transcribed into A, whereas other modified nucleosides are transcribed correctly, except for m7G-46, which is sometimes transcribed into T. In contrast, synthetic tRNALys,3, an RNA PBS primer, and a DNA PBS primer are completely reverse-transcribed. In the presence of an acceptor template, (+) strand DNA transfer is efficient only with templates containing natural tRNALys,3 or the RNA PBS primer. Sequence analysis of transfer products revealed frequent errors at the transfer site with synthetic tRNALys,3, not observed with natural tRNALys,3. Thus, modified nucleoside m1A-58, present in all retroviral tRNA primers, appears to be important for both efficacy and fidelity of (+) strand DNA transfer. We show that other factors such as the nature of the (-) PBS of the acceptor template and the RNase H activity of RT also influence the efficacy of (+) strand DNA transfer.},
note = {0021-9258
Journal Article},
keywords = {*RNA, *Transcription, Acid, Base, Calf, Conformation, Data, DNA, Genetic, Gov't, H, HIV-1, HIV-1/*physiology, Lys/*metabolism, Molecular, Non-U.S., Nucleic, post-transcriptional, Processing, Reverse, Ribonuclease, RNA, Sequence, Support, Templates, Thymus/metabolism, Transcriptase/metabolism, Transfer, Viral/*metabolism, Viral/metabolism},
pubstate = {published},
tppubtype = {article}
}
During HIV reverse transcription, (+) strand DNA synthesis is primed by an RNase H-resistant sequence, the polypurine tract, and continues as far as a 18-nt double-stranded RNA region corresponding to the 3' end of tRNALys,3 hybridized to the viral primer binding site (PBS). Before (+) strand DNA transfer, reverse transcriptase (RT) needs to unwind the double-stranded tRNA-PBS RNA in order to reverse-transcribe the 3' end of primer tRNALys,3. Since the detailed mechanism of (+) strand DNA transfer remains incompletely understood, we developed an in vitro system to closely examine this mechanism, composed of HIV 5' RNA, natural modified tRNALys,3, synthetic unmodified tRNALys,3 or oligonucleotides (RNA or DNA) complementary to the PBS, as well as the viral proteins RT and nucleocapsid protein (NCp7). Prior to (+) strand DNA transfer, RT stalls at the double-stranded tRNA-PBS RNA complex and is able to reverse-transcribe modified nucleosides of natural tRNALys,3. Modified nucleoside m1A-58 of natural tRNALys,3 is only partially effective as a stop signal, as RT can transcribe as far as the hyper-modified adenosine (ms2t6A-37) in the anticodon loop. m1A-58 is almost always transcribed into A, whereas other modified nucleosides are transcribed correctly, except for m7G-46, which is sometimes transcribed into T. In contrast, synthetic tRNALys,3, an RNA PBS primer, and a DNA PBS primer are completely reverse-transcribed. In the presence of an acceptor template, (+) strand DNA transfer is efficient only with templates containing natural tRNALys,3 or the RNA PBS primer. Sequence analysis of transfer products revealed frequent errors at the transfer site with synthetic tRNALys,3, not observed with natural tRNALys,3. Thus, modified nucleoside m1A-58, present in all retroviral tRNA primers, appears to be important for both efficacy and fidelity of (+) strand DNA transfer. We show that other factors such as the nature of the (-) PBS of the acceptor template and the RNase H activity of RT also influence the efficacy of (+) strand DNA transfer.
Perreau V. M., Keith G., Holmes W. M., Przykorska A., Santos M. A., Tuite M. F.
The Candida albicans CUG-decoding ser-tRNA has an atypical anticodon stem-loop structure Journal Article
In: J Mol Biol, vol. 293, no. 5, pp. 1039-53, 1999, (0022-2836 Journal Article).
Abstract | BibTeX | Tags: *Nucleic, Acid, albicans/*genetics, Anticodon/*chemistry/*genetics/metabolism, Base, Candida, cerevisiae/genetics, Code/genetics, Conformation, Evolution, Fungal/chemistry/genetics/metabolism, Genetic, Gov't, Imidazoles/metabolism, Lead/metabolism, Methylation, Methyltransferases/metabolism, Molecular, Mutation/genetics, Non-P.H.S., Non-U.S., Nucleosides/genetics/metabolism, P.H.S., Ribonucleases/metabolism, RNA, Saccharomyces, Sequence, Ser/*chemistry/*genetics/metabolism, Solutions, Support, Transfer, tRNA, U.S.
@article{,
title = {The Candida albicans CUG-decoding ser-tRNA has an atypical anticodon stem-loop structure},
author = { V. M. Perreau and G. Keith and W. M. Holmes and A. Przykorska and M. A. Santos and M. F. Tuite},
year = {1999},
date = {1999-01-01},
journal = {J Mol Biol},
volume = {293},
number = {5},
pages = {1039-53},
abstract = {In many Candida species, the leucine CUG codon is decoded by a tRNA with two unusual properties: it is a ser-tRNA and, uniquely, has guanosine at position 33 (G33). Using a combination of enzymatic (V1 RNase, RnI nuclease) and chemical (Pb(2+), imidazole) probing of the native Candida albicans ser-tRNACAG, we demonstrate that the overall tertiary structure of this tRNA resembles that of a ser-tRNA rather than a leu-tRNA, except within the anticodon arm where there is considerable disruption of the anticodon stem. Using non-modified in vitro transcripts of the C. albicans ser-tRNACAG carrying G, C, U or A at position 33, we demonstrate that it is specifically a G residue at this position that induces the atypical anticodon stem structure. Further quantitative evidence for an unusual structure in the anticodon arm of the G33-tRNA is provided by the observed change in kinetics of methylation of the G at position 37, by purified Escherichia coli m(1)G37 methyltransferase. We conclude that the anticodon arm distortion, induced by a guanosine base at position 33 in the anticodon loop of this novel tRNA, results in reduced decoding ability which has facilitated the evolution of this tRNA without extinction of the species encoding it.},
note = {0022-2836
Journal Article},
keywords = {*Nucleic, Acid, albicans/*genetics, Anticodon/*chemistry/*genetics/metabolism, Base, Candida, cerevisiae/genetics, Code/genetics, Conformation, Evolution, Fungal/chemistry/genetics/metabolism, Genetic, Gov't, Imidazoles/metabolism, Lead/metabolism, Methylation, Methyltransferases/metabolism, Molecular, Mutation/genetics, Non-P.H.S., Non-U.S., Nucleosides/genetics/metabolism, P.H.S., Ribonucleases/metabolism, RNA, Saccharomyces, Sequence, Ser/*chemistry/*genetics/metabolism, Solutions, Support, Transfer, tRNA, U.S.},
pubstate = {published},
tppubtype = {article}
}
In many Candida species, the leucine CUG codon is decoded by a tRNA with two unusual properties: it is a ser-tRNA and, uniquely, has guanosine at position 33 (G33). Using a combination of enzymatic (V1 RNase, RnI nuclease) and chemical (Pb(2+), imidazole) probing of the native Candida albicans ser-tRNACAG, we demonstrate that the overall tertiary structure of this tRNA resembles that of a ser-tRNA rather than a leu-tRNA, except within the anticodon arm where there is considerable disruption of the anticodon stem. Using non-modified in vitro transcripts of the C. albicans ser-tRNACAG carrying G, C, U or A at position 33, we demonstrate that it is specifically a G residue at this position that induces the atypical anticodon stem structure. Further quantitative evidence for an unusual structure in the anticodon arm of the G33-tRNA is provided by the observed change in kinetics of methylation of the G at position 37, by purified Escherichia coli m(1)G37 methyltransferase. We conclude that the anticodon arm distortion, induced by a guanosine base at position 33 in the anticodon loop of this novel tRNA, results in reduced decoding ability which has facilitated the evolution of this tRNA without extinction of the species encoding it.
1998
Brigotti M., Keith G., Pallanca A., Carnicelli D., Alvergna P., Dirheimer G., Montanaro L., Sperti S.
Identification of the tRNAs which up-regulate agrostin, barley RIP and PAP-S, three ribosome-inactivating proteins of plant origin Journal Article
In: FEBS Lett, vol. 431, no. 2, pp. 259-62, 1998, (0014-5793 Journal Article).
Abstract | BibTeX | Tags: &, Acid, Adenosine, Base, Conformation, Data, effects/*metabolism, Gov't, Hordeum/metabolism, Hydrolases/*metabolism, Molecular, N-Glycosyl, Non-U.S., Nucleic, Plant, Plant/chemistry/isolation, Proteins/drug, purification/*metabolism, RNA, Sequence, Support, Transfer/chemistry/isolation, Triphosphate/pharmacology, Up-Regulation
@article{,
title = {Identification of the tRNAs which up-regulate agrostin, barley RIP and PAP-S, three ribosome-inactivating proteins of plant origin},
author = { M. Brigotti and G. Keith and A. Pallanca and D. Carnicelli and P. Alvergna and G. Dirheimer and L. Montanaro and S. Sperti},
year = {1998},
date = {1998-01-01},
journal = {FEBS Lett},
volume = {431},
number = {2},
pages = {259-62},
abstract = {Ribosome-inactivating proteins (RIP) are RNA-N-glycosidases widely diffused in plants which depurinate ribosomal RNA at a specific universally conserved position, A4324 in rat ribosomes. A small group of RIPs (cofactor-dependent RIPs) require ATP and tRNA to reach maximal activity on isolated ribosomes. The tRNA which stimulates gelonin was identified as tRNA(Trp). The present paper reports the identification of three other tRNAs which stimulate agrostin (tRNA(Ala)), barley RIP (tRNA(Ala), tRNA(Val)) and PAP-S (tRNA(Gly)), while for tritin-S no particular stimulating tRNA emerged. The sequences of tRNA(Val) and tRNA(Gly) correspond to the already known ones (rabbit and man, respectively). The tRNA(Ala) (anticodon IGC) identifies a new isoacceptor. Only the stimulating activity of the tRNA(Ala) for agrostin approaches the specificity previously observed for the couple gelonin-tRNA(Trp).},
note = {0014-5793
Journal Article},
keywords = {&, Acid, Adenosine, Base, Conformation, Data, effects/*metabolism, Gov't, Hordeum/metabolism, Hydrolases/*metabolism, Molecular, N-Glycosyl, Non-U.S., Nucleic, Plant, Plant/chemistry/isolation, Proteins/drug, purification/*metabolism, RNA, Sequence, Support, Transfer/chemistry/isolation, Triphosphate/pharmacology, Up-Regulation},
pubstate = {published},
tppubtype = {article}
}
Ribosome-inactivating proteins (RIP) are RNA-N-glycosidases widely diffused in plants which depurinate ribosomal RNA at a specific universally conserved position, A4324 in rat ribosomes. A small group of RIPs (cofactor-dependent RIPs) require ATP and tRNA to reach maximal activity on isolated ribosomes. The tRNA which stimulates gelonin was identified as tRNA(Trp). The present paper reports the identification of three other tRNAs which stimulate agrostin (tRNA(Ala)), barley RIP (tRNA(Ala), tRNA(Val)) and PAP-S (tRNA(Gly)), while for tritin-S no particular stimulating tRNA emerged. The sequences of tRNA(Val) and tRNA(Gly) correspond to the already known ones (rabbit and man, respectively). The tRNA(Ala) (anticodon IGC) identifies a new isoacceptor. Only the stimulating activity of the tRNA(Ala) for agrostin approaches the specificity previously observed for the couple gelonin-tRNA(Trp).
Friant S., Heyman T., Bystrom A. S., Wilhelm M., Wilhelm F. X.
Interactions between Ty1 retrotransposon RNA and the T and D regions of the tRNA(iMet) primer are required for initiation of reverse transcription in vivo Journal Article
In: Mol Cell Biol, vol. 18, no. 2, pp. 799-806, 1998, (0270-7306 Journal Article).
Abstract | BibTeX | Tags: *Retroelements, *Transcription, Acid, Base, Binding, cerevisiae, Conformation, Data, DNA, Fungal/*metabolism, Fungal/biosynthesis, Genetic, Gov't, Met/*metabolism, Molecular, Mutagenesis, Non-U.S., Nucleic, Primers, Replication, RNA, Saccharomyces, Sequence, Sites, Support, Transfer
@article{,
title = {Interactions between Ty1 retrotransposon RNA and the T and D regions of the tRNA(iMet) primer are required for initiation of reverse transcription in vivo},
author = { S. Friant and T. Heyman and A. S. Bystrom and M. Wilhelm and F. X. Wilhelm},
year = {1998},
date = {1998-01-01},
journal = {Mol Cell Biol},
volume = {18},
number = {2},
pages = {799-806},
abstract = {Reverse transcription of the Saccharomyces cerevisiae Ty1 retrotransposon is primed by tRNA(iMet) base paired to the primer binding site (PBS) near the 5' end of Ty1 genomic RNA. The 10-nucleotide PBS is complementary to the last 10 nucleotides of the acceptor stem of tRNA(iMet). A structural probing study of the interactions between the Ty1 RNA template and the tRNA(iMet) primer showed that besides interactions between the PBS and the 3' end of tRNA(iMet), three short regions of Ty1 RNA, named boxes 0, 1, and 2.1, interact with the T and D stems and loops of tRNA(iMet). To determine if these sequences are important for the reverse transcription pathway of the Ty1 retrotransposon, mutant Ty1 elements and tRNA(iMet) were tested for the ability to support transposition. We show that the Ty1 boxes and the complementary sequences in the T and D stems and loops of tRNA(iMet) contain bases that are critical for Ty1 retrotransposition. Disruption of 1 or 2 bp between tRNA(iMet) and box 0, 1, or 2.1 dramatically decreases the level of transposition. Compensatory mutations which restore base pairing between the primer and the template restore transposition. Analysis of the reverse transcription intermediates generated inside Ty1 virus-like particles indicates that initiation of minus-strand strong-stop DNA synthesis is affected by mutations disrupting complementarity between Ty1 RNA and primer tRNA(iMet).},
note = {0270-7306
Journal Article},
keywords = {*Retroelements, *Transcription, Acid, Base, Binding, cerevisiae, Conformation, Data, DNA, Fungal/*metabolism, Fungal/biosynthesis, Genetic, Gov't, Met/*metabolism, Molecular, Mutagenesis, Non-U.S., Nucleic, Primers, Replication, RNA, Saccharomyces, Sequence, Sites, Support, Transfer},
pubstate = {published},
tppubtype = {article}
}
Reverse transcription of the Saccharomyces cerevisiae Ty1 retrotransposon is primed by tRNA(iMet) base paired to the primer binding site (PBS) near the 5' end of Ty1 genomic RNA. The 10-nucleotide PBS is complementary to the last 10 nucleotides of the acceptor stem of tRNA(iMet). A structural probing study of the interactions between the Ty1 RNA template and the tRNA(iMet) primer showed that besides interactions between the PBS and the 3' end of tRNA(iMet), three short regions of Ty1 RNA, named boxes 0, 1, and 2.1, interact with the T and D stems and loops of tRNA(iMet). To determine if these sequences are important for the reverse transcription pathway of the Ty1 retrotransposon, mutant Ty1 elements and tRNA(iMet) were tested for the ability to support transposition. We show that the Ty1 boxes and the complementary sequences in the T and D stems and loops of tRNA(iMet) contain bases that are critical for Ty1 retrotransposition. Disruption of 1 or 2 bp between tRNA(iMet) and box 0, 1, or 2.1 dramatically decreases the level of transposition. Compensatory mutations which restore base pairing between the primer and the template restore transposition. Analysis of the reverse transcription intermediates generated inside Ty1 virus-like particles indicates that initiation of minus-strand strong-stop DNA synthesis is affected by mutations disrupting complementarity between Ty1 RNA and primer tRNA(iMet).
1997
Bergdoll M., Remy M. H., Cagnon C., Masson J. M., Dumas P.
Proline-dependent oligomerization with arm exchange Journal Article
In: Structure, vol. 5, no. 3, pp. 391-401, 1997, (0969-2126 Journal Article).
Abstract | BibTeX | Tags: *Acetyltransferases, *Dimerization, *Protein, Acid, Alignment, Amino, Aminotransferases/chemistry, Animals, Aspartate, ATPase/chemistry, Bacterial, Binding, Cattle, Chickens, Comparative, Conformation, Data, Folding, Heart/enzymology, Human, mitochondria, Models, Molecular, Mutagenesis, Na(+)-K(+)-Exchanging, Pancreatic/chemistry, Plant, Proline/*physiology, Protein, Proteins/chemistry, Pyrophosphatases/chemistry, Ribonuclease, Sequence, Site-Directed, Structural, Study, Viral, Viruses/chemistry
@article{,
title = {Proline-dependent oligomerization with arm exchange},
author = { M. Bergdoll and M. H. Remy and C. Cagnon and J. M. Masson and P. Dumas},
year = {1997},
date = {1997-01-01},
journal = {Structure},
volume = {5},
number = {3},
pages = {391-401},
abstract = {BACKGROUND: Oligomerization is often necessary for protein activity or regulation and its efficiency is fundamental for the cell. The quaternary structure of a large number of oligomers consists of protomers tightly anchored to each other by exchanged arms or swapped domains. However, nothing is known about how the arms can be kept in a favourable conformation before such an oligomerization. RESULTS: Upon examination of such quaternary structures, we observe an extremely frequent occurrence of proline residues at the point where the arm leaves the protomer. Sequence alignment and site-directed mutagenesis confirm the importance of these prolines. The conservation of these residues at the hinge regions can be explained by the constraints that they impose on polypeptide conformation and dynamics: by rigidifying the mainchain, prolines favour extended conformations of arms thus favouring oligomerization, and may prevent interaction of the arms with the core of the protomer. CONCLUSIONS: Hinge prolines can be considered as 'quaternary structure helpers'. The presence of a proline should be considered when searching for a determinant of oligomerization with arm exchange and could be used to engineer synthetic oligomers or to displace a monomers to oligomers equilibrium by mutation of this proline residue.},
note = {0969-2126
Journal Article},
keywords = {*Acetyltransferases, *Dimerization, *Protein, Acid, Alignment, Amino, Aminotransferases/chemistry, Animals, Aspartate, ATPase/chemistry, Bacterial, Binding, Cattle, Chickens, Comparative, Conformation, Data, Folding, Heart/enzymology, Human, mitochondria, Models, Molecular, Mutagenesis, Na(+)-K(+)-Exchanging, Pancreatic/chemistry, Plant, Proline/*physiology, Protein, Proteins/chemistry, Pyrophosphatases/chemistry, Ribonuclease, Sequence, Site-Directed, Structural, Study, Viral, Viruses/chemistry},
pubstate = {published},
tppubtype = {article}
}
BACKGROUND: Oligomerization is often necessary for protein activity or regulation and its efficiency is fundamental for the cell. The quaternary structure of a large number of oligomers consists of protomers tightly anchored to each other by exchanged arms or swapped domains. However, nothing is known about how the arms can be kept in a favourable conformation before such an oligomerization. RESULTS: Upon examination of such quaternary structures, we observe an extremely frequent occurrence of proline residues at the point where the arm leaves the protomer. Sequence alignment and site-directed mutagenesis confirm the importance of these prolines. The conservation of these residues at the hinge regions can be explained by the constraints that they impose on polypeptide conformation and dynamics: by rigidifying the mainchain, prolines favour extended conformations of arms thus favouring oligomerization, and may prevent interaction of the arms with the core of the protomer. CONCLUSIONS: Hinge prolines can be considered as 'quaternary structure helpers'. The presence of a proline should be considered when searching for a determinant of oligomerization with arm exchange and could be used to engineer synthetic oligomers or to displace a monomers to oligomers equilibrium by mutation of this proline residue.
Wilhelm M., Heyman T., Friant S., Wilhelm F. X.
Heterogeneous terminal structure of Ty1 and Ty3 reverse transcripts Journal Article
In: Nucleic Acids Res, vol. 25, no. 11, pp. 2161-6, 1997, (0305-1048 Journal Article).
Abstract | BibTeX | Tags: *Nucleic, *Transcription, Acid, Calf, Chain, Conformation, DNA, Fungal/*chemistry/metabolism, Genetic, Gov't, H, Hybridization, Non-U.S., Nucleic, Plasmids/chemistry/genetics/metabolism, Polymerase, Reaction, Replication, Retroelements/*genetics, Ribonuclease, RNA, Support, Thymus/metabolism, Transfer/chemistry
@article{,
title = {Heterogeneous terminal structure of Ty1 and Ty3 reverse transcripts},
author = { M. Wilhelm and T. Heyman and S. Friant and F. X. Wilhelm},
year = {1997},
date = {1997-01-01},
journal = {Nucleic Acids Res},
volume = {25},
number = {11},
pages = {2161-6},
abstract = {A specific terminal structure of preintegrative DNA is required for transposition of retroviruses and LTR-retrotransposons. We have used an anchored PCR technique to map the 3'ends of DNA intermediates synthesized inside yeast Ty1 and Ty3 retrotransposon virus-like particles. We find that, unlike retroviruses, Ty1 replicated DNA does not have two extra base pairs at its 3'ends. In contrast some Ty3 preintegrative DNA molecules have two extra nucleotides at the 3'end of upstream and downstream long terminal repeats. Moreover we find that some molecules of replicated Ty3 DNA have more than two extra nucleotides at the 3'end of the upstream LTR. This observation could be accounted for by imprecise RNAse H cutting of the PPT sequence. The site of Ty1 and Ty3 plus-strand strong-stop DNA termination was also examined. Our results confirm that the prominent Ty1 and Ty3 plus-strand strong-stop molecules harbor 12 tRNA templated bases but also show that some Ty1 and Ty3 plus-strand strong-stop DNA molecules harbor less tRNA templated bases. We propose that these less than full length plus-strand molecules could be active intermediates in Ty retrotransposon replication.},
note = {0305-1048
Journal Article},
keywords = {*Nucleic, *Transcription, Acid, Calf, Chain, Conformation, DNA, Fungal/*chemistry/metabolism, Genetic, Gov't, H, Hybridization, Non-U.S., Nucleic, Plasmids/chemistry/genetics/metabolism, Polymerase, Reaction, Replication, Retroelements/*genetics, Ribonuclease, RNA, Support, Thymus/metabolism, Transfer/chemistry},
pubstate = {published},
tppubtype = {article}
}
A specific terminal structure of preintegrative DNA is required for transposition of retroviruses and LTR-retrotransposons. We have used an anchored PCR technique to map the 3'ends of DNA intermediates synthesized inside yeast Ty1 and Ty3 retrotransposon virus-like particles. We find that, unlike retroviruses, Ty1 replicated DNA does not have two extra base pairs at its 3'ends. In contrast some Ty3 preintegrative DNA molecules have two extra nucleotides at the 3'end of upstream and downstream long terminal repeats. Moreover we find that some molecules of replicated Ty3 DNA have more than two extra nucleotides at the 3'end of the upstream LTR. This observation could be accounted for by imprecise RNAse H cutting of the PPT sequence. The site of Ty1 and Ty3 plus-strand strong-stop DNA termination was also examined. Our results confirm that the prominent Ty1 and Ty3 plus-strand strong-stop molecules harbor 12 tRNA templated bases but also show that some Ty1 and Ty3 plus-strand strong-stop DNA molecules harbor less tRNA templated bases. We propose that these less than full length plus-strand molecules could be active intermediates in Ty retrotransposon replication.
1996
Friant S., Heyman T., Wilhelm F. X., Wilhelm M.
Role of RNA primers in initiation of minus-strand and plus-strand DNA synthesis of the yeast retrotransposon Ty1 Journal Article
In: Biochimie, vol. 78, no. 7, pp. 674-80, 1996, (0300-9084 Journal Article).
Abstract | BibTeX | Tags: *DNA, Acid, Bacterial/*metabolism, Complementary/metabolism, Conformation, Data, DNA, Elements, Gov't, Molecular, Mutagenesis, Non-U.S., Nucleic, Replication, RNA, RNA/*metabolism, Sequence, Support, Transposable
@article{,
title = {Role of RNA primers in initiation of minus-strand and plus-strand DNA synthesis of the yeast retrotransposon Ty1},
author = { S. Friant and T. Heyman and F. X. Wilhelm and M. Wilhelm},
year = {1996},
date = {1996-01-01},
journal = {Biochimie},
volume = {78},
number = {7},
pages = {674-80},
abstract = {The Ty1 retrotransposon of the yeast Saccharomyces cerevisiae is a long terminal repeat mobile genetic element that transposes through an RNA intermediate. Initiation of minus-strand and plus-strand DNA synthesis are two critical steps during reverse transcription of the retrotransposon genome. Initiation of minus-strand DNA synthesis of the Ty1 element is primed by the cytoplasmic initiator methionine tRNA base paired to the primer binding site near the 5' end of the genomic RNA. A structural probing study of the primer tRNA-Ty1 RNA binary complex reveals that besides interactions between the primer binding site and the last 10 nucleotides at the 3' end of the primer tRNA, three short regions of Ty1 RNA named box 0, box 1 and box 2.1 interact with the T and D stems and loops of the primer tRNA. Some in vivo results underline the functional importance of the nucleotide sequence of the boxes and suggest that extended interactions between genomic Ty1 RNA and the primer tRNA play a role in the reverse transcription pathway. Plus-strand DNA synthesis is initiated from an RNase H resistant oligoribonucleotide spanning a purine-rich sequence, the polypurine tract (PPT). Two sites of initiation located at the 5' boundary of the 3' long terminal repeat (PPT1) and near the middle of the TyB (pol) gene in the integrase coding sequence (PPT2) have been identified in the genome of Ty1. The two PPTs have an identical sequence, TGGGTGGTA. Mutations replacing purines by pyrimidines in this sequence significantly diminish or abolish initiation of plus-strand DNA synthesis. Ty1 elements bearing a mutated PPT2 sequence are not defective for transposition whereas mutations in PPT1 abolish transposition.},
note = {0300-9084
Journal Article},
keywords = {*DNA, Acid, Bacterial/*metabolism, Complementary/metabolism, Conformation, Data, DNA, Elements, Gov't, Molecular, Mutagenesis, Non-U.S., Nucleic, Replication, RNA, RNA/*metabolism, Sequence, Support, Transposable},
pubstate = {published},
tppubtype = {article}
}
The Ty1 retrotransposon of the yeast Saccharomyces cerevisiae is a long terminal repeat mobile genetic element that transposes through an RNA intermediate. Initiation of minus-strand and plus-strand DNA synthesis are two critical steps during reverse transcription of the retrotransposon genome. Initiation of minus-strand DNA synthesis of the Ty1 element is primed by the cytoplasmic initiator methionine tRNA base paired to the primer binding site near the 5' end of the genomic RNA. A structural probing study of the primer tRNA-Ty1 RNA binary complex reveals that besides interactions between the primer binding site and the last 10 nucleotides at the 3' end of the primer tRNA, three short regions of Ty1 RNA named box 0, box 1 and box 2.1 interact with the T and D stems and loops of the primer tRNA. Some in vivo results underline the functional importance of the nucleotide sequence of the boxes and suggest that extended interactions between genomic Ty1 RNA and the primer tRNA play a role in the reverse transcription pathway. Plus-strand DNA synthesis is initiated from an RNase H resistant oligoribonucleotide spanning a purine-rich sequence, the polypurine tract (PPT). Two sites of initiation located at the 5' boundary of the 3' long terminal repeat (PPT1) and near the middle of the TyB (pol) gene in the integrase coding sequence (PPT2) have been identified in the genome of Ty1. The two PPTs have an identical sequence, TGGGTGGTA. Mutations replacing purines by pyrimidines in this sequence significantly diminish or abolish initiation of plus-strand DNA synthesis. Ty1 elements bearing a mutated PPT2 sequence are not defective for transposition whereas mutations in PPT1 abolish transposition.
Friant S., Heyman T., Wilhelm M. L., Wilhelm F. X.
Extended interactions between the primer tRNAi(Met) and genomic RNA of the yeast Ty1 retrotransposon Journal Article
In: Nucleic Acids Res, vol. 24, no. 3, pp. 441-9, 1996, (0305-1048 Journal Article).
Abstract | BibTeX | Tags: Acid, Base, cerevisiae, Conformation, Data, Gov't, Met/genetics/*metabolism, Molecular, Mutation, Non-U.S., Nucleic, Retroelements/*genetics, RNA, RNA/genetics/*metabolism, Saccharomyces, Sequence, structure, Support, Transfer
@article{,
title = {Extended interactions between the primer tRNAi(Met) and genomic RNA of the yeast Ty1 retrotransposon},
author = { S. Friant and T. Heyman and M. L. Wilhelm and F. X. Wilhelm},
year = {1996},
date = {1996-01-01},
journal = {Nucleic Acids Res},
volume = {24},
number = {3},
pages = {441-9},
abstract = {Reverse transcription of the yeast Ty1 retrotransposon is primed by tRNAi(Met) base paired to the primer binding site near the 5'-end of Ty1 genomic RNA. To understand the molecular basis of the tRNAi(Met)-Ty1 RNA interaction the secondary structure of the binary complex was analysed. Enzymatic probes were used to test the conformation of tRNAi(Met) and of Ty1 RNA in the free form and in the complex. A secondary structure model of the tRNAi(Met) Ty1 RNA complex consistent with the probing data was constructed with the help of a computer program. The model shows that besides interactions between the primer binding site and the last 10 nt at the 3'-end of tRNAi(Met), three short regions of Ty1 RNA named boxes 0, 1 and 2.1 interact with the T and D stems and loops of tRNAiMet. Mutations were made in the boxes or in the complementary sequences of tRNAi(Met) to study the contribution of these sequences to formation of the complex. We find that interaction with at least one of the two boxes 0 or 1 is absolutely required for efficient annealing of the two RNAs. Sequence comparison showing that the primary sequence of the boxes is strictly conserved in Ty1 and Ty2 elements and previously published in vivo results underline the functional importance of the primary sequence of the boxes and suggest that extended interactions between genomic Ty1 RNA and the primary tRNAi(Met) play a role in the reverse transcription pathway.},
note = {0305-1048
Journal Article},
keywords = {Acid, Base, cerevisiae, Conformation, Data, Gov't, Met/genetics/*metabolism, Molecular, Mutation, Non-U.S., Nucleic, Retroelements/*genetics, RNA, RNA/genetics/*metabolism, Saccharomyces, Sequence, structure, Support, Transfer},
pubstate = {published},
tppubtype = {article}
}
Reverse transcription of the yeast Ty1 retrotransposon is primed by tRNAi(Met) base paired to the primer binding site near the 5'-end of Ty1 genomic RNA. To understand the molecular basis of the tRNAi(Met)-Ty1 RNA interaction the secondary structure of the binary complex was analysed. Enzymatic probes were used to test the conformation of tRNAi(Met) and of Ty1 RNA in the free form and in the complex. A secondary structure model of the tRNAi(Met) Ty1 RNA complex consistent with the probing data was constructed with the help of a computer program. The model shows that besides interactions between the primer binding site and the last 10 nt at the 3'-end of tRNAi(Met), three short regions of Ty1 RNA named boxes 0, 1 and 2.1 interact with the T and D stems and loops of tRNAiMet. Mutations were made in the boxes or in the complementary sequences of tRNAi(Met) to study the contribution of these sequences to formation of the complex. We find that interaction with at least one of the two boxes 0 or 1 is absolutely required for efficient annealing of the two RNAs. Sequence comparison showing that the primary sequence of the boxes is strictly conserved in Ty1 and Ty2 elements and previously published in vivo results underline the functional importance of the primary sequence of the boxes and suggest that extended interactions between genomic Ty1 RNA and the primary tRNAi(Met) play a role in the reverse transcription pathway.
de Barros J. P. Pais, Keith G., Adlouni C. El, Glasser A. L., Mack G., Dirheimer G., Desgres J.
2'-O-methyl-5-formylcytidine (f5Cm), a new modified nucleotide at the 'wobble' of two cytoplasmic tRNAs Leu (NAA) from bovine liver Journal Article
In: Nucleic Acids Res, vol. 24, no. 8, pp. 1489-96, 1996, (0305-1048 Journal Article).
Abstract | BibTeX | Tags: &, Acid, Acyl/*chemistry/isolation, Amino, Animals, Base, Borohydrides/chemistry, Cattle, Cells, Conformation, Cytidine/*analogs, Cytoplasm, Data, derivatives/chemistry/isolation, Fragmentography, Gov't, Hela, Human, Liver/*chemistry, Mass, Molecular, Non-U.S., Nucleic, purification, RNA, Sequence, structure, Support, Transfer
@article{,
title = {2'-O-methyl-5-formylcytidine (f5Cm), a new modified nucleotide at the 'wobble' of two cytoplasmic tRNAs Leu (NAA) from bovine liver},
author = { J. P. Pais de Barros and G. Keith and C. El Adlouni and A. L. Glasser and G. Mack and G. Dirheimer and J. Desgres},
year = {1996},
date = {1996-01-01},
journal = {Nucleic Acids Res},
volume = {24},
number = {8},
pages = {1489-96},
abstract = {The nucleotide analysis of a cytoplasmic tRNA(Leu) isolated from bovine liver revealed the presence of an unknown modified nucleotide N. The corresponding N nucleoside was isolated by different enzymatic and chromatographic protocols from a partially purified preparation of this tRNA(Leu). Its chemical characterization was determined from its chromatographic properties, UV-absorption spectroscopy and mass spectrometric measurements, as well as from those of the borohydride reduced N nucleoside and its etheno-trimethylsilyl derivative. The structure of N was established as 2'-O-methyl-5-formylcytidine (f5CM), and its reduced derivative as 2'-O-methyl-5-hydroxy-methylcytidine (om5Cm). By sequencing the bovine liver tRNA(Leu), the structure of the anticodon was determined as f5CmAA. In addition, the nucleotide sequence showed two primary structures differing only by the nucleotide 47c which is either uridine or adenosine. The two slightly differing bovine liver tRNAs-Leu(f5CmAA) are the only tRNAs so far sequenced which contain f5Cm. The role of such a modified cytidine at the first position of the anticodon is discussed in terms of decoding properties for the UUG and UUA leucine codons. Recently, precise evidence was obtained for the presence of f5Cm at the same position in tRNAs(Leu)(NAA) isolated from rabbit and lamb liver. Therefore, the 2'-O-methyl-5-formyl modification of cytidine at position 34 could be a general feature of cytoplasmic tRNAs(Leu)(NAA) in mammals.},
note = {0305-1048
Journal Article},
keywords = {&, Acid, Acyl/*chemistry/isolation, Amino, Animals, Base, Borohydrides/chemistry, Cattle, Cells, Conformation, Cytidine/*analogs, Cytoplasm, Data, derivatives/chemistry/isolation, Fragmentography, Gov't, Hela, Human, Liver/*chemistry, Mass, Molecular, Non-U.S., Nucleic, purification, RNA, Sequence, structure, Support, Transfer},
pubstate = {published},
tppubtype = {article}
}
The nucleotide analysis of a cytoplasmic tRNA(Leu) isolated from bovine liver revealed the presence of an unknown modified nucleotide N. The corresponding N nucleoside was isolated by different enzymatic and chromatographic protocols from a partially purified preparation of this tRNA(Leu). Its chemical characterization was determined from its chromatographic properties, UV-absorption spectroscopy and mass spectrometric measurements, as well as from those of the borohydride reduced N nucleoside and its etheno-trimethylsilyl derivative. The structure of N was established as 2'-O-methyl-5-formylcytidine (f5CM), and its reduced derivative as 2'-O-methyl-5-hydroxy-methylcytidine (om5Cm). By sequencing the bovine liver tRNA(Leu), the structure of the anticodon was determined as f5CmAA. In addition, the nucleotide sequence showed two primary structures differing only by the nucleotide 47c which is either uridine or adenosine. The two slightly differing bovine liver tRNAs-Leu(f5CmAA) are the only tRNAs so far sequenced which contain f5Cm. The role of such a modified cytidine at the first position of the anticodon is discussed in terms of decoding properties for the UUG and UUA leucine codons. Recently, precise evidence was obtained for the presence of f5Cm at the same position in tRNAs(Leu)(NAA) isolated from rabbit and lamb liver. Therefore, the 2'-O-methyl-5-formyl modification of cytidine at position 34 could be a general feature of cytoplasmic tRNAs(Leu)(NAA) in mammals.
1995
Gabryszuk J., Keith G., Monko M., Kuligowska E., Dirheimer G., Szarkowski J. W., Przykorska A.
Structural specificity of nuclease from wheat chloroplasts stroma Journal Article
In: Nucleic Acids Symp Ser, no. 33, pp. 115-9, 1995, (0261-3166 Journal Article).
Abstract | BibTeX | Tags: &, Acid, Asp/chemistry/genetics/metabolism, Base, Binding, Chloroplasts/*enzymology, Conformation, Data, Endonucleases/isolation, Fungal/chemistry/genetics/metabolism, Gov't, Molecular, Non-U.S., Nucleic, Phe/chemistry/genetics/metabolism, purification/*metabolism, RNA, RNA/chemistry/metabolism, Sequence, Sites, Specificity, Substrate, Support, Transfer, Triticum/*enzymology
@article{,
title = {Structural specificity of nuclease from wheat chloroplasts stroma},
author = { J. Gabryszuk and G. Keith and M. Monko and E. Kuligowska and G. Dirheimer and J. W. Szarkowski and A. Przykorska},
year = {1995},
date = {1995-01-01},
journal = {Nucleic Acids Symp Ser},
number = {33},
pages = {115-9},
abstract = {A single-strand-specific nuclease from wheat chloroplasts (ChS nuclease) was tested as a tool for RNA secondary and tertiary structure investigations, using yeast tRNA(Phe) and yeast tRNA(Asp) as models. In tRNA(Phe) the nuclease introduced main primary cleavages at positions U33, A35 and A36 in the anticodon-loop and G18 and G19 in the D-loop. In tRNA(Asp) the main primary cleavages occurred at positions U33, G34 and U35 in the anticodon-loop and the lower one at position C20:1 in the D-loop. No primary cleavages were observed within the double-stranded stems. Because ChS nuclease has (i) a low molecular weight, (ii) a wide pH range of action (5.0 to 7.5) (iii) no divalent cation requirement in the reaction mixture and (iv) can be obtained as a pure protein in rather large quantities it appeared to be a very good tool for secondary and tertiary structural studies of RNAs.},
note = {0261-3166
Journal Article},
keywords = {&, Acid, Asp/chemistry/genetics/metabolism, Base, Binding, Chloroplasts/*enzymology, Conformation, Data, Endonucleases/isolation, Fungal/chemistry/genetics/metabolism, Gov't, Molecular, Non-U.S., Nucleic, Phe/chemistry/genetics/metabolism, purification/*metabolism, RNA, RNA/chemistry/metabolism, Sequence, Sites, Specificity, Substrate, Support, Transfer, Triticum/*enzymology},
pubstate = {published},
tppubtype = {article}
}
A single-strand-specific nuclease from wheat chloroplasts (ChS nuclease) was tested as a tool for RNA secondary and tertiary structure investigations, using yeast tRNA(Phe) and yeast tRNA(Asp) as models. In tRNA(Phe) the nuclease introduced main primary cleavages at positions U33, A35 and A36 in the anticodon-loop and G18 and G19 in the D-loop. In tRNA(Asp) the main primary cleavages occurred at positions U33, G34 and U35 in the anticodon-loop and the lower one at position C20:1 in the D-loop. No primary cleavages were observed within the double-stranded stems. Because ChS nuclease has (i) a low molecular weight, (ii) a wide pH range of action (5.0 to 7.5) (iii) no divalent cation requirement in the reaction mixture and (iv) can be obtained as a pure protein in rather large quantities it appeared to be a very good tool for secondary and tertiary structural studies of RNAs.
O'Connor M., Brunelli C. A., Firpo M. A., Gregory S. T., Lieberman K. R., Lodmell J. S., Moine H., Ryk D. I. Van, Dahlberg A. E.
Genetic probes of ribosomal RNA function Journal Article
In: Biochem Cell Biol, vol. 73, no. 11-12, pp. 859-68, 1995, (0829-8211 Journal Article Review Review, Tutorial).
Abstract | BibTeX | Tags: 16S/genetics, Acid, Base, Conformation, Data, Gov't, Messenger/genetics, Molecular, Mutation, Non-U.S., Nucleic, P.H.S., Probes, Ribosomal, Ribosomal/*genetics, RNA, Sequence, Support, Transfer/genetics, U.S.
@article{,
title = {Genetic probes of ribosomal RNA function},
author = { M. O'Connor and C. A. Brunelli and M. A. Firpo and S. T. Gregory and K. R. Lieberman and J. S. Lodmell and H. Moine and D. I. Van Ryk and A. E. Dahlberg},
year = {1995},
date = {1995-01-01},
journal = {Biochem Cell Biol},
volume = {73},
number = {11-12},
pages = {859-68},
abstract = {We have used a genetic approach to uncover the functional roles of rRNA in protein synthesis. Mutations were constructed in a cloned rrn operon by site-directed mutagenesis or isolated by genetic selections following random mutagenesis. We have identified mutations that affect each step in the process of translation. The data are consistent with the results of biochemical and phylogenetic analyses but, in addition, have provided novel information on regions of rRNA not previously investigated.},
note = {0829-8211
Journal Article
Review
Review, Tutorial},
keywords = {16S/genetics, Acid, Base, Conformation, Data, Gov't, Messenger/genetics, Molecular, Mutation, Non-U.S., Nucleic, P.H.S., Probes, Ribosomal, Ribosomal/*genetics, RNA, Sequence, Support, Transfer/genetics, U.S.},
pubstate = {published},
tppubtype = {article}
}
We have used a genetic approach to uncover the functional roles of rRNA in protein synthesis. Mutations were constructed in a cloned rrn operon by site-directed mutagenesis or isolated by genetic selections following random mutagenesis. We have identified mutations that affect each step in the process of translation. The data are consistent with the results of biochemical and phylogenetic analyses but, in addition, have provided novel information on regions of rRNA not previously investigated.
1994
Dumas P., Bergdoll M., Cagnon C., Masson J. M.
Crystal structure and site-directed mutagenesis of a bleomycin resistance protein and their significance for drug sequestering Journal Article
In: EMBO J, vol. 13, no. 11, pp. 2483-92, 1994, (0261-4189 Journal Article).
Abstract | BibTeX | Tags: *Acetyltransferases, &, Acid, Amino, Bacterial, Bacterial/*genetics, Base, Binding, Bleomycin/*metabolism/pharmacology, Conformation, Crystallization, Crystallography, Data, Drug, Fusion, Genes, Gov't, Microbial/genetics, Models, Molecular, Mutagenesis, Non-U.S., Protein, Proteins/*chemistry/genetics/isolation, Proteins/isolation, purification, purification/metabolism, Recombinant, Relationship, Resistance, Secondary, Sequence, Site-Directed, Sites, Structural, structure, Structure-Activity, Support, X-Ray
@article{,
title = {Crystal structure and site-directed mutagenesis of a bleomycin resistance protein and their significance for drug sequestering},
author = { P. Dumas and M. Bergdoll and C. Cagnon and J. M. Masson},
year = {1994},
date = {1994-01-01},
journal = {EMBO J},
volume = {13},
number = {11},
pages = {2483-92},
abstract = {The antibiotic bleomycin, a strong DNA cutting agent, is naturally produced by actinomycetes which have developed a resistance mechanism against such a lethal compound. The crystal structure, at 2.3 A resolution, of a bleomycin resistance protein of 14 kDa reveals a structure in two halves with the same alpha/beta fold despite no sequence similarity. The crystal packing shows compact dimers with a hydrophobic interface and involved in mutual chain exchange. Two independent solution studies (analytical centrifugation and light scattering) showed that this dimeric form is not a packing artefact but is indeed the functional one. Furthermore, light scattering also showed that one dimer binds two antibiotic molecules as expected. A crevice located at the dimer interface, as well as the results of a site-directed mutagenesis study, led to a model wherein two bleomycin molecules are completely sequestered by one dimer. This provides a novel insight into antibiotic resistance due to drug sequestering, and probably also into drug transport and excretion.},
note = {0261-4189
Journal Article},
keywords = {*Acetyltransferases, &, Acid, Amino, Bacterial, Bacterial/*genetics, Base, Binding, Bleomycin/*metabolism/pharmacology, Conformation, Crystallization, Crystallography, Data, Drug, Fusion, Genes, Gov't, Microbial/genetics, Models, Molecular, Mutagenesis, Non-U.S., Protein, Proteins/*chemistry/genetics/isolation, Proteins/isolation, purification, purification/metabolism, Recombinant, Relationship, Resistance, Secondary, Sequence, Site-Directed, Sites, Structural, structure, Structure-Activity, Support, X-Ray},
pubstate = {published},
tppubtype = {article}
}
The antibiotic bleomycin, a strong DNA cutting agent, is naturally produced by actinomycetes which have developed a resistance mechanism against such a lethal compound. The crystal structure, at 2.3 A resolution, of a bleomycin resistance protein of 14 kDa reveals a structure in two halves with the same alpha/beta fold despite no sequence similarity. The crystal packing shows compact dimers with a hydrophobic interface and involved in mutual chain exchange. Two independent solution studies (analytical centrifugation and light scattering) showed that this dimeric form is not a packing artefact but is indeed the functional one. Furthermore, light scattering also showed that one dimer binds two antibiotic molecules as expected. A crevice located at the dimer interface, as well as the results of a site-directed mutagenesis study, led to a model wherein two bleomycin molecules are completely sequestered by one dimer. This provides a novel insight into antibiotic resistance due to drug sequestering, and probably also into drug transport and excretion.
Heyman T., Agoutin B., Fix C., Dirheimer G., Keith G.
Yeast serine isoacceptor tRNAs: variations of their content as a function of growth conditions and primary structure of the minor tRNA(Ser)GCU Journal Article
In: FEBS Lett, vol. 347, no. 2-3, pp. 143-6, 1994, (0014-5793 Journal Article).
Abstract | BibTeX | Tags: &, Acid, Anticodon, Base, cerevisiae/*genetics/*growth, Conformation, Culture, Data, development, Fungal/*chemistry, Galactose, Hybridization, Media, Molecular, Nucleic, Probes, RNA, Saccharomyces, Sequence, Ser/analysis/*chemistry, Transfer, Transfer/*chemistry
@article{,
title = {Yeast serine isoacceptor tRNAs: variations of their content as a function of growth conditions and primary structure of the minor tRNA(Ser)GCU},
author = { T. Heyman and B. Agoutin and C. Fix and G. Dirheimer and G. Keith},
year = {1994},
date = {1994-01-01},
journal = {FEBS Lett},
volume = {347},
number = {2-3},
pages = {143-6},
abstract = {The primary structure of Saccharomyces cerevisiae tRNA(Ser)GCU is presented (EMBL database accession No. X74268 S. cerevisiae tRNA-Ser). In addition, quantitation of the relative amounts of serine isoaccepting tRNAs in yeast grown on different media showed that the minor tRNA(Ser)GCU decreased while the major tRNA(Ser)AGA increased as the growth rate and the cellular protein content increased. The minor species, tRNA(Ser)CGA and tRNA(Ser)UGA, were not separated by our gel system, however, taken together they appeared to vary in the same way as tRNA(Ser)GCU. These data suggest a growth rate dependence of yeast tRNAs similar to that previously described for E. coli tRNAs.},
note = {0014-5793
Journal Article},
keywords = {&, Acid, Anticodon, Base, cerevisiae/*genetics/*growth, Conformation, Culture, Data, development, Fungal/*chemistry, Galactose, Hybridization, Media, Molecular, Nucleic, Probes, RNA, Saccharomyces, Sequence, Ser/analysis/*chemistry, Transfer, Transfer/*chemistry},
pubstate = {published},
tppubtype = {article}
}
The primary structure of Saccharomyces cerevisiae tRNA(Ser)GCU is presented (EMBL database accession No. X74268 S. cerevisiae tRNA-Ser). In addition, quantitation of the relative amounts of serine isoaccepting tRNAs in yeast grown on different media showed that the minor tRNA(Ser)GCU decreased while the major tRNA(Ser)AGA increased as the growth rate and the cellular protein content increased. The minor species, tRNA(Ser)CGA and tRNA(Ser)UGA, were not separated by our gel system, however, taken together they appeared to vary in the same way as tRNA(Ser)GCU. These data suggest a growth rate dependence of yeast tRNAs similar to that previously described for E. coli tRNAs.
Moine H., Dahlberg A. E.
Mutations in helix 34 of Escherichia coli 16 S ribosomal RNA have multiple effects on ribosome function and synthesis Journal Article
In: J Mol Biol, vol. 243, no. 3, pp. 402-12, 1994, (0022-2836 Journal Article).
Abstract | BibTeX | Tags: *Mutation, *Nucleic, *Translation, &, 16S/*chemistry/genetics, Acid, Base, beta-Galactosidase/genetics, Codon, coli/*genetics/growth, Conformation, Data, development, Escherichia, Genetic, Gov't, Molecular, Non-U.S., P.H.S., Ribosomal, Ribosomes/*metabolism, RNA, Sequence, Support, Terminator, U.S.
@article{,
title = {Mutations in helix 34 of Escherichia coli 16 S ribosomal RNA have multiple effects on ribosome function and synthesis},
author = { H. Moine and A. E. Dahlberg},
year = {1994},
date = {1994-01-01},
journal = {J Mol Biol},
volume = {243},
number = {3},
pages = {402-12},
abstract = {Helix 34 of E. coli 16 S rRNA (1046 to 1067 and 1189 to 1211) has been proposed to participate directly in the termination of translation at UGA stop codons. We have constructed mutations in this helix in plasmid-encoded rDNA to explore the specific functional roles of the sequence UCAUCA (1199 to 1204) and a secondary structure also involving positions 1054 and 1057-1058. The rRNA mutations were analyzed for their effects on in vivo translational accuracy (stop codon readthrough and frameshifting) as well as growth rate, ribosome synthesis and incorporation into polysomes. Mutations at positions 1054, 1057, 1058, 1199 and 1200 had significant effects on translational accuracy, causing non-specific readthrough of all three stop codons as well as enhanced +1 and -1 frameshifting. Mutations at 1202 and 1203, however, had no effect. The incorporation of deleterious mutant subunits into 70 S ribosomes and polysomes was severely reduced and was associated with a slower growth rate and increased synthesis of host-encoded ribosomes. These data support the proposal that helix 34 is an essential component of the decoding center of the 30 S ribosomal subunit and is not restricted in function to UGA-codon specific termination.},
note = {0022-2836
Journal Article},
keywords = {*Mutation, *Nucleic, *Translation, &, 16S/*chemistry/genetics, Acid, Base, beta-Galactosidase/genetics, Codon, coli/*genetics/growth, Conformation, Data, development, Escherichia, Genetic, Gov't, Molecular, Non-U.S., P.H.S., Ribosomal, Ribosomes/*metabolism, RNA, Sequence, Support, Terminator, U.S.},
pubstate = {published},
tppubtype = {article}
}
Helix 34 of E. coli 16 S rRNA (1046 to 1067 and 1189 to 1211) has been proposed to participate directly in the termination of translation at UGA stop codons. We have constructed mutations in this helix in plasmid-encoded rDNA to explore the specific functional roles of the sequence UCAUCA (1199 to 1204) and a secondary structure also involving positions 1054 and 1057-1058. The rRNA mutations were analyzed for their effects on in vivo translational accuracy (stop codon readthrough and frameshifting) as well as growth rate, ribosome synthesis and incorporation into polysomes. Mutations at positions 1054, 1057, 1058, 1199 and 1200 had significant effects on translational accuracy, causing non-specific readthrough of all three stop codons as well as enhanced +1 and -1 frameshifting. Mutations at 1202 and 1203, however, had no effect. The incorporation of deleterious mutant subunits into 70 S ribosomes and polysomes was severely reduced and was associated with a slower growth rate and increased synthesis of host-encoded ribosomes. These data support the proposal that helix 34 is an essential component of the decoding center of the 30 S ribosomal subunit and is not restricted in function to UGA-codon specific termination.
1993
el Adlouni C., Keith G., Dirheimer G., Szarkowski J. W., Przykorska A.
Rye nuclease I as a tool for structural studies of tRNAs with large variable arms Journal Article
In: Nucleic Acids Res, vol. 21, no. 4, pp. 941-7, 1993, (0305-1048 Journal Article).
Abstract | BibTeX | Tags: *Nucleotidases, Acid, Animals, Anticodon, Base, Cattle, cereale/*enzymology, cerevisiae, Conformation, Data, Gov't, Leu/chemistry, Molecular, Non-U.S., Nucleic, RNA, Saccharomyces, Secale, Sequence, Ser/chemistry, Support, Transfer, Transfer/*chemistry
@article{,
title = {Rye nuclease I as a tool for structural studies of tRNAs with large variable arms},
author = { C. el Adlouni and G. Keith and G. Dirheimer and J. W. Szarkowski and A. Przykorska},
year = {1993},
date = {1993-01-01},
journal = {Nucleic Acids Res},
volume = {21},
number = {4},
pages = {941-7},
abstract = {A single-strand-specific nuclease from rye germ (Rn nuclease I) was used for secondary and tertiary structure investigations of tRNAs with large variable arms (class II tRNAs). We have studied the structure in solution of two recently sequenced tRNA(Leu): yeast tRNA(Leu)(ncm5UmAA) and bovine tRNA(Leu)(XmAA) as well as yeast tRNA(Leu)(UAG), tRNA(Leu)(m5CAA) and tRNA(Ser)(IGA). The latter is the only tRNA with a long variable arm for which the secondary and tertiary structure has already been studied by use of chemical probes and computer modelling. The data obtained in this work showed that the general model of class II tRNAs proposed by others for tRNA(Ser) can be extended to tRNAs(Leu) as well. However interesting differences in the structure of tRNAs(Leu) versus tRNA(Ser)(IGA) were also noticed. The main difference was observed in the accessibility of the variable loops to nucleolytic attack of Rn nuclease I: variable loops of all studied tRNA(Leu) species were cut by Rn nuclease I, while that of yeast tRNA(Ser)(IGA) was not. This could be due to differences in stability of the variable arms and the lengths of their loops which are 3 and 4 nucleotides in tRNA(Ser)(IGA) and tRNAs(Leu) respectively.},
note = {0305-1048
Journal Article},
keywords = {*Nucleotidases, Acid, Animals, Anticodon, Base, Cattle, cereale/*enzymology, cerevisiae, Conformation, Data, Gov't, Leu/chemistry, Molecular, Non-U.S., Nucleic, RNA, Saccharomyces, Secale, Sequence, Ser/chemistry, Support, Transfer, Transfer/*chemistry},
pubstate = {published},
tppubtype = {article}
}
A single-strand-specific nuclease from rye germ (Rn nuclease I) was used for secondary and tertiary structure investigations of tRNAs with large variable arms (class II tRNAs). We have studied the structure in solution of two recently sequenced tRNA(Leu): yeast tRNA(Leu)(ncm5UmAA) and bovine tRNA(Leu)(XmAA) as well as yeast tRNA(Leu)(UAG), tRNA(Leu)(m5CAA) and tRNA(Ser)(IGA). The latter is the only tRNA with a long variable arm for which the secondary and tertiary structure has already been studied by use of chemical probes and computer modelling. The data obtained in this work showed that the general model of class II tRNAs proposed by others for tRNA(Ser) can be extended to tRNAs(Leu) as well. However interesting differences in the structure of tRNAs(Leu) versus tRNA(Ser)(IGA) were also noticed. The main difference was observed in the accessibility of the variable loops to nucleolytic attack of Rn nuclease I: variable loops of all studied tRNA(Leu) species were cut by Rn nuclease I, while that of yeast tRNA(Ser)(IGA) was not. This could be due to differences in stability of the variable arms and the lengths of their loops which are 3 and 4 nucleotides in tRNA(Ser)(IGA) and tRNAs(Leu) respectively.
Pochart P., Agoutin B., Fix C., Keith G., Heyman T.
A very poorly expressed tRNA(Ser) is highly concentrated together with replication primer initiator tRNA(Met) in the yeast Ty1 virus-like particles Journal Article
In: Nucleic Acids Res, vol. 21, no. 7, pp. 1517-21, 1993, (0305-1048 Journal Article).
Abstract | BibTeX | Tags: &, Acid, Base, cerevisiae/metabolism, Conformation, Data, development, DNA, Electrophoresis, Elements/*physiology, Gel, Met/metabolism, Molecular, Nucleic, Retroviridae/*growth, RNA, Saccharomyces, Sequence, Ser/*metabolism, Transfer, Transposable, Two-Dimensional, Viral/*metabolism
@article{,
title = {A very poorly expressed tRNA(Ser) is highly concentrated together with replication primer initiator tRNA(Met) in the yeast Ty1 virus-like particles},
author = { P. Pochart and B. Agoutin and C. Fix and G. Keith and T. Heyman},
year = {1993},
date = {1993-01-01},
journal = {Nucleic Acids Res},
volume = {21},
number = {7},
pages = {1517-21},
abstract = {The analysis of the tRNAs associated to the virus-like particles produced by the Ty1 element revealed the specific packaging of three major tRNA species, in about equal amounts: the replication primer initiator tRNA(Met), the tRNA(Ser)AGA and a tRNA undetected until now as an expressed species in yeast. The latter tRNA is coded by the already described tDNA(Ser)GCT. This tRNA is enriched more than 150 fold in the particles as compared to its content in total cellular tRNA where it represents less than 0.1% (initiator tRNA(Met) and tRNA(Ser)AGA being 11 and 4 fold enriched respectively). This tRNA is the only species coded by the tDNA(Ser)GCT gene which is found in three copies per genome since no other corresponding expressed tRNA could be detected. This gene is thus very poorly expressed. The high concentration of tRNA(Ser)GCU in the particles compared to its very low cellular content led us to consider its possible implication in Ty specific processes.},
note = {0305-1048
Journal Article},
keywords = {&, Acid, Base, cerevisiae/metabolism, Conformation, Data, development, DNA, Electrophoresis, Elements/*physiology, Gel, Met/metabolism, Molecular, Nucleic, Retroviridae/*growth, RNA, Saccharomyces, Sequence, Ser/*metabolism, Transfer, Transposable, Two-Dimensional, Viral/*metabolism},
pubstate = {published},
tppubtype = {article}
}
The analysis of the tRNAs associated to the virus-like particles produced by the Ty1 element revealed the specific packaging of three major tRNA species, in about equal amounts: the replication primer initiator tRNA(Met), the tRNA(Ser)AGA and a tRNA undetected until now as an expressed species in yeast. The latter tRNA is coded by the already described tDNA(Ser)GCT. This tRNA is enriched more than 150 fold in the particles as compared to its content in total cellular tRNA where it represents less than 0.1% (initiator tRNA(Met) and tRNA(Ser)AGA being 11 and 4 fold enriched respectively). This tRNA is the only species coded by the tDNA(Ser)GCT gene which is found in three copies per genome since no other corresponding expressed tRNA could be detected. This gene is thus very poorly expressed. The high concentration of tRNA(Ser)GCU in the particles compared to its very low cellular content led us to consider its possible implication in Ty specific processes.
Santos M. A., Keith G., Tuite M. F.
Non-standard translational events in Candida albicans mediated by an unusual seryl-tRNA with a 5'-CAG-3' (leucine) anticodon Journal Article
In: EMBO J, vol. 12, no. 2, pp. 607-16, 1993, (0261-4189 Journal Article).
Abstract | BibTeX | Tags: *Anticodon, *Translation, &, Acid, albicans/*genetics, Base, Candida, Cloning, Conformation, Data, DNA, Fungal, Fungal/chemistry/genetics/isolation, Genes, Genetic, Gov't, Leucine/*genetics, Molecular, Non-U.S., Nucleic, purification, RNA, Sequence, Ser/chemistry/*genetics/isolation, Support, Transfer
@article{,
title = {Non-standard translational events in Candida albicans mediated by an unusual seryl-tRNA with a 5'-CAG-3' (leucine) anticodon},
author = { M. A. Santos and G. Keith and M. F. Tuite},
year = {1993},
date = {1993-01-01},
journal = {EMBO J},
volume = {12},
number = {2},
pages = {607-16},
abstract = {From in vitro translation studies we have previously demonstrated the existence of an apparent efficient UAG (amber) suppressor tRNA in the dimorphic fungus Candida albicans (Santos et al., 1990). Using an in vitro assay for termination codon readthrough the tRNA responsible was purified to homogeneity from C.albicans cells. The determined sequence of the purified tRNA predicts a 5'-CAG-3' anticodon that should decode the leucine codon CUG and not the UAG termination codon as originally hypothesized. However, the tRNA(CAG) sequence shows greater nucleotide homology with seryl-tRNAs from the closely related yeast Saccharomyces cerevisiae than with leucyl-tRNAs from the same species. In vitro tRNA-charging studies demonstrated that the purified tRNA(CAG) is charged with Ser. The gene encoding the tRNA was cloned from C.albicans by a PCR-based strategy and DNA sequence analysis confirmed both the structure of the tRNA(CAG) and the absence of any introns in the tRNA gene. The copy number of the tRNA(CAG) gene (1-2 genes per haploid genome) is in agreement with the relatively low abundance (< 0.5% total tRNA) of this tRNA. In vitro translation studies revealed that the purified tRNA(CAG) could induce apparent translational bypass of all three termination codons. However, peptide mapping of in vitro translation products demonstrated that the tRNA(CAG) induces translational misreading in the amino-terminal region of two RNA templates employed, namely the rabbit alpha- and beta-globin mRNAs. These results suggest that the C.albicans tRNA(CAG) is not an 'omnipotent' suppressor tRNA but rather may mediate a novel non-standard translational event in vitro during the translation of the CUG codon. The possible nature of this non-standard translation event is discussed in the context of both the unusual structural features of the tRNA(CAG) and its in vitro behaviour.},
note = {0261-4189
Journal Article},
keywords = {*Anticodon, *Translation, &, Acid, albicans/*genetics, Base, Candida, Cloning, Conformation, Data, DNA, Fungal, Fungal/chemistry/genetics/isolation, Genes, Genetic, Gov't, Leucine/*genetics, Molecular, Non-U.S., Nucleic, purification, RNA, Sequence, Ser/chemistry/*genetics/isolation, Support, Transfer},
pubstate = {published},
tppubtype = {article}
}
From in vitro translation studies we have previously demonstrated the existence of an apparent efficient UAG (amber) suppressor tRNA in the dimorphic fungus Candida albicans (Santos et al., 1990). Using an in vitro assay for termination codon readthrough the tRNA responsible was purified to homogeneity from C.albicans cells. The determined sequence of the purified tRNA predicts a 5'-CAG-3' anticodon that should decode the leucine codon CUG and not the UAG termination codon as originally hypothesized. However, the tRNA(CAG) sequence shows greater nucleotide homology with seryl-tRNAs from the closely related yeast Saccharomyces cerevisiae than with leucyl-tRNAs from the same species. In vitro tRNA-charging studies demonstrated that the purified tRNA(CAG) is charged with Ser. The gene encoding the tRNA was cloned from C.albicans by a PCR-based strategy and DNA sequence analysis confirmed both the structure of the tRNA(CAG) and the absence of any introns in the tRNA gene. The copy number of the tRNA(CAG) gene (1-2 genes per haploid genome) is in agreement with the relatively low abundance (< 0.5% total tRNA) of this tRNA. In vitro translation studies revealed that the purified tRNA(CAG) could induce apparent translational bypass of all three termination codons. However, peptide mapping of in vitro translation products demonstrated that the tRNA(CAG) induces translational misreading in the amino-terminal region of two RNA templates employed, namely the rabbit alpha- and beta-globin mRNAs. These results suggest that the C.albicans tRNA(CAG) is not an 'omnipotent' suppressor tRNA but rather may mediate a novel non-standard translational event in vitro during the translation of the CUG codon. The possible nature of this non-standard translation event is discussed in the context of both the unusual structural features of the tRNA(CAG) and its in vitro behaviour.
1992
Przykorska A., el Adlouni C., Keith G., Szarkowski J. W., Dirheimer G.
Structural specificity of Rn nuclease I as probed on yeast tRNA(Phe) and tRNA(Asp) Journal Article
In: Nucleic Acids Res, vol. 20, no. 4, pp. 659-63, 1992, (0305-1048 Journal Article).
Abstract | BibTeX | Tags: Acid, Asp/chemistry/genetics/*metabolism, Base, cereale, Composition, Conformation, Data, Gov't, Molecular, Non-U.S., Nucleic, Pancreatic/*metabolism, Phe/chemistry/genetics/*metabolism, Ribonuclease, RNA, Secale, Sequence, Specificity, Substrate, Support, Transfer, Yeasts/genetics
@article{,
title = {Structural specificity of Rn nuclease I as probed on yeast tRNA(Phe) and tRNA(Asp)},
author = { A. Przykorska and C. el Adlouni and G. Keith and J. W. Szarkowski and G. Dirheimer},
year = {1992},
date = {1992-01-01},
journal = {Nucleic Acids Res},
volume = {20},
number = {4},
pages = {659-63},
abstract = {A single-strand-specific nuclease from rye germ (Rn nuclease I) was characterized as a tool for secondary and tertiary structure investigation of RNAs. To test the procedure, yeast tRNA(Phe) and tRNA(Asp) for which the tertiary structures are known, as well as the 3'-half of tRNA(Asp) were used as substrates. In tRNA(Phe) the nuclease introduced main primary cuts at positions U33 and A35 of the anticodon loop and G18 and G19 of the D loop. No primary cuts were observed within the double stranded stems. In tRNA(Asp) the main cuts occurred at positions U33, G34, U35, C36 of the anticodon loop and G18 and C20:1 positions in the D loop. No cuts were observed in the T loop in intact tRNA(Asp) but strong primary cleavages occurred at positions psi 55, C56, A57 within that loop in the absence of the tertiary interactions between T and D loops (use of 3'-half tRNA(Asp)). These results show that Rn nuclease I is specific for exposed single-stranded regions.},
note = {0305-1048
Journal Article},
keywords = {Acid, Asp/chemistry/genetics/*metabolism, Base, cereale, Composition, Conformation, Data, Gov't, Molecular, Non-U.S., Nucleic, Pancreatic/*metabolism, Phe/chemistry/genetics/*metabolism, Ribonuclease, RNA, Secale, Sequence, Specificity, Substrate, Support, Transfer, Yeasts/genetics},
pubstate = {published},
tppubtype = {article}
}
A single-strand-specific nuclease from rye germ (Rn nuclease I) was characterized as a tool for secondary and tertiary structure investigation of RNAs. To test the procedure, yeast tRNA(Phe) and tRNA(Asp) for which the tertiary structures are known, as well as the 3'-half of tRNA(Asp) were used as substrates. In tRNA(Phe) the nuclease introduced main primary cuts at positions U33 and A35 of the anticodon loop and G18 and G19 of the D loop. No primary cuts were observed within the double stranded stems. In tRNA(Asp) the main cuts occurred at positions U33, G34, U35, C36 of the anticodon loop and G18 and C20:1 positions in the D loop. No cuts were observed in the T loop in intact tRNA(Asp) but strong primary cleavages occurred at positions psi 55, C56, A57 within that loop in the absence of the tertiary interactions between T and D loops (use of 3'-half tRNA(Asp)). These results show that Rn nuclease I is specific for exposed single-stranded regions.
