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1996
Isel C, Ehresmann C, Ehresmann B, Marquet R
In: Pharm Acta Helv, vol. 71, no. 1, pp. 11-19, 1996, ISBN: 8786994, (0031-6865 Journal Article).
Abstract | Links | BibTeX | Tags: Amino Acid Sequence Binding Sites DNA Primers HIV-1/*chemistry Human Nucleic Acid Conformation RNA, Lys/*chemistry RNA, MARQUET, Non-U.S. Gov't, Transfer, Unité ARN, Viral/*chemistry Solutions Support
@article{,
title = {Determining the conformation of RNAs in solution. Application to a retroviral system: structure of the HIV-1 primer binding site region and effect of tRNA(3Lys) binding},
author = {C Isel and C Ehresmann and B Ehresmann and R Marquet},
url = {http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=8786994},
isbn = {8786994},
year = {1996},
date = {1996-01-01},
journal = {Pharm Acta Helv},
volume = {71},
number = {1},
pages = {11-19},
abstract = {RNAs play a crucial and central role in a large variety of biological functions obviously linked to the wide variety of structures that they can adopt. Understanding the function of RNAs thus requires the knowledge of their two- and three-dimensional structures. We describe in detail the way to access the secondary structure of RNAs, by combining sequence comparison, secondary structure prediction by computer and, mainly, experimental data obtained by probing with chemicals and ribonucleases. These approaches were used to investigate secondary structure of the region containing the primer binding site of HIV-1 genomic RNA either free or involved in the binary complex with the replication primer tRNA(3Lys).},
note = {0031-6865
Journal Article},
keywords = {Amino Acid Sequence Binding Sites DNA Primers HIV-1/*chemistry Human Nucleic Acid Conformation RNA, Lys/*chemistry RNA, MARQUET, Non-U.S. Gov't, Transfer, Unité ARN, Viral/*chemistry Solutions Support},
pubstate = {published},
tppubtype = {article}
}
RNAs play a crucial and central role in a large variety of biological functions obviously linked to the wide variety of structures that they can adopt. Understanding the function of RNAs thus requires the knowledge of their two- and three-dimensional structures. We describe in detail the way to access the secondary structure of RNAs, by combining sequence comparison, secondary structure prediction by computer and, mainly, experimental data obtained by probing with chemicals and ribonucleases. These approaches were used to investigate secondary structure of the region containing the primer binding site of HIV-1 genomic RNA either free or involved in the binary complex with the replication primer tRNA(3Lys).
1994
Felden B, Florentz C, Giege R, Westhof E
Solution structure of the 3'-end of brome mosaic virus genomic RNAs. Conformational mimicry with canonical tRNAs Journal Article
In: J Mol Biol, vol. 235, no. 2, pp. 508-531, 1994, ISBN: 8289279, (0022-2836 Journal Article).
Abstract | Links | BibTeX | Tags: Base Sequence Bromovirus/*genetics Computer Simulation Models, FLORENTZ, Genetic Models, Molecular Molecular Sequence Data Nucleic Acid Conformation RNA, Non-U.S. Gov't, Transfer, Tyr/*chemistry RNA, Unité ARN, Viral/*chemistry Solutions Support
@article{,
title = {Solution structure of the 3'-end of brome mosaic virus genomic RNAs. Conformational mimicry with canonical tRNAs},
author = {B Felden and C Florentz and R Giege and E Westhof},
url = {http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=8289279},
isbn = {8289279},
year = {1994},
date = {1994-01-01},
journal = {J Mol Biol},
volume = {235},
number = {2},
pages = {508-531},
abstract = {The conformation of the last 201 nucleotides located at the 3'-end of brome mosaic virus (BMV) RNAs was investigated in solution using different chemical and enzymatic probes. Bases were probed with dimethylsulfate (which methylates N-1 positions of A, N-3 positions of C and N-7 positions of G), a carbodiimide (which modifies N-1 positions of G and N-3 positions of U) and diethylpyrocarbonate (which modifies N-7 positions of A). Ribonucleases T1, U2 and S1 were used to map unpaired nucleotides and ribonuclease V1 to monitor paired bases or stacked nucleotides. Cleavage or modification sites were detected by gel electrophoresis either indirectly by analyzing DNA sequence patterns generated by primer extension with reverse transcriptase of the modified RNAs or by direct identification within the statistical cleavage patterns of the RNA. On the basis of these biochemical results, an atomic model was built by computer modeling and its stereochemistry refined. The deduced secondary structure of the RNA confirms data previously proposed by others but contains additional base-pairs (A27-U32, A28-G31, G41-A134, G64-C68, U80-A99, G81-A98, G88-U91, G100-U126, U104-U125, G162-G166 and A172-A191), one new tertiary long-range interaction (U103-U164) and a small triple helical conformation with (G41-A134)-A18 and (C42-G133)-A17 interactions. The new secondary structure also indicates the existence of a second pseudoknot involving pairing between residues A181 to A184 and residues U197 to U194, outside the domain conferring tyrosylation ability to BMV RNA. The main outcome from the model stems from its intricate folding, which allows a new assignment for the domains mimicking the anticodon- and D-loop regions of tRNA. Interestingly, the stem and loop region found structurally to be analogous to the anticodon arm of tRNA(Tyr) does not contain the tyrosine anticodon involved in the aminoacylation process. The structural analogies with canonical tRNA(Tyr) illustrate the functional mimicry existing between the BMV RNA structure and canonical tRNA(Tyr) that allows for their efficient aminoacylation by tyrosyl-tRNA synthetase. This structural model rationalizes mutagenic and footprinting data that have established the importance of specific regions of the viral RNA for recognition by its replicase, (ATP,CTP):tRNA nucleotidyl-transferase and yeast tyrosyl-tRNA synthetase. The new fold has biological implications that can be used as a predictive tool for elaborating new experiments.},
note = {0022-2836
Journal Article},
keywords = {Base Sequence Bromovirus/*genetics Computer Simulation Models, FLORENTZ, Genetic Models, Molecular Molecular Sequence Data Nucleic Acid Conformation RNA, Non-U.S. Gov't, Transfer, Tyr/*chemistry RNA, Unité ARN, Viral/*chemistry Solutions Support},
pubstate = {published},
tppubtype = {article}
}
The conformation of the last 201 nucleotides located at the 3'-end of brome mosaic virus (BMV) RNAs was investigated in solution using different chemical and enzymatic probes. Bases were probed with dimethylsulfate (which methylates N-1 positions of A, N-3 positions of C and N-7 positions of G), a carbodiimide (which modifies N-1 positions of G and N-3 positions of U) and diethylpyrocarbonate (which modifies N-7 positions of A). Ribonucleases T1, U2 and S1 were used to map unpaired nucleotides and ribonuclease V1 to monitor paired bases or stacked nucleotides. Cleavage or modification sites were detected by gel electrophoresis either indirectly by analyzing DNA sequence patterns generated by primer extension with reverse transcriptase of the modified RNAs or by direct identification within the statistical cleavage patterns of the RNA. On the basis of these biochemical results, an atomic model was built by computer modeling and its stereochemistry refined. The deduced secondary structure of the RNA confirms data previously proposed by others but contains additional base-pairs (A27-U32, A28-G31, G41-A134, G64-C68, U80-A99, G81-A98, G88-U91, G100-U126, U104-U125, G162-G166 and A172-A191), one new tertiary long-range interaction (U103-U164) and a small triple helical conformation with (G41-A134)-A18 and (C42-G133)-A17 interactions. The new secondary structure also indicates the existence of a second pseudoknot involving pairing between residues A181 to A184 and residues U197 to U194, outside the domain conferring tyrosylation ability to BMV RNA. The main outcome from the model stems from its intricate folding, which allows a new assignment for the domains mimicking the anticodon- and D-loop regions of tRNA. Interestingly, the stem and loop region found structurally to be analogous to the anticodon arm of tRNA(Tyr) does not contain the tyrosine anticodon involved in the aminoacylation process. The structural analogies with canonical tRNA(Tyr) illustrate the functional mimicry existing between the BMV RNA structure and canonical tRNA(Tyr) that allows for their efficient aminoacylation by tyrosyl-tRNA synthetase. This structural model rationalizes mutagenic and footprinting data that have established the importance of specific regions of the viral RNA for recognition by its replicase, (ATP,CTP):tRNA nucleotidyl-transferase and yeast tyrosyl-tRNA synthetase. The new fold has biological implications that can be used as a predictive tool for elaborating new experiments.
