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Competitive folding of RNA structures at a termination–antitermination site
Antitermination is a regulatory process based on the competitive folding of terminator–antiterminator structures that can form in the leader region of nascent transcripts. In the case of the Bacillus subtilis licS gene involved in β-glucosides utilization, the binding of the antitermination protein...
Autores principales: | , , , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
Cold Spring Harbor Laboratory Press
2017
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5393181/ https://www.ncbi.nlm.nih.gov/pubmed/28235843 http://dx.doi.org/10.1261/rna.060178.116 |
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author | Ait-Bara, Soraya Clerté, Caroline Declerck, Nathalie Margeat, Emmanuel |
author_facet | Ait-Bara, Soraya Clerté, Caroline Declerck, Nathalie Margeat, Emmanuel |
author_sort | Ait-Bara, Soraya |
collection | PubMed |
description | Antitermination is a regulatory process based on the competitive folding of terminator–antiterminator structures that can form in the leader region of nascent transcripts. In the case of the Bacillus subtilis licS gene involved in β-glucosides utilization, the binding of the antitermination protein LicT to a short RNA hairpin (RAT) prevents the formation of an overlapping terminator and thereby allows transcription to proceed. Here, we monitored in vitro the competition between termination and antitermination by combining bulk and single-molecule fluorescence-based assays using labeled RNA oligonucleotide constructs of increasing length that mimic the progressive transcription of the terminator invading the antiterminator hairpin. Although high affinity binding is abolished as soon as the antiterminator basal stem is disrupted by the invading terminator, LicT can still bind and promote closing of the partially unfolded RAT hairpin. However, binding no longer occurs once the antiterminator structure has been disrupted by the full-length terminator. Based on these findings, we propose a kinetic competition model for the sequential events taking place at the termination–antitermination site, where LicT needs to capture its RAT target before completion of the terminator to remain tightly bound during RNAP pausing, before finally dissociating irreversibly from the elongated licS transcript. |
format | Online Article Text |
id | pubmed-5393181 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2017 |
publisher | Cold Spring Harbor Laboratory Press |
record_format | MEDLINE/PubMed |
spelling | pubmed-53931812018-05-01 Competitive folding of RNA structures at a termination–antitermination site Ait-Bara, Soraya Clerté, Caroline Declerck, Nathalie Margeat, Emmanuel RNA Article Antitermination is a regulatory process based on the competitive folding of terminator–antiterminator structures that can form in the leader region of nascent transcripts. In the case of the Bacillus subtilis licS gene involved in β-glucosides utilization, the binding of the antitermination protein LicT to a short RNA hairpin (RAT) prevents the formation of an overlapping terminator and thereby allows transcription to proceed. Here, we monitored in vitro the competition between termination and antitermination by combining bulk and single-molecule fluorescence-based assays using labeled RNA oligonucleotide constructs of increasing length that mimic the progressive transcription of the terminator invading the antiterminator hairpin. Although high affinity binding is abolished as soon as the antiterminator basal stem is disrupted by the invading terminator, LicT can still bind and promote closing of the partially unfolded RAT hairpin. However, binding no longer occurs once the antiterminator structure has been disrupted by the full-length terminator. Based on these findings, we propose a kinetic competition model for the sequential events taking place at the termination–antitermination site, where LicT needs to capture its RAT target before completion of the terminator to remain tightly bound during RNAP pausing, before finally dissociating irreversibly from the elongated licS transcript. Cold Spring Harbor Laboratory Press 2017-05 /pmc/articles/PMC5393181/ /pubmed/28235843 http://dx.doi.org/10.1261/rna.060178.116 Text en © 2017 Ait-Bara et al.; Published by Cold Spring Harbor Laboratory Press for the RNA Society http://creativecommons.org/licenses/by-nc/4.0/ This article is distributed exclusively by the RNA Society for the first 12 months after the full-issue publication date (see http://rnajournal.cshlp.org/site/misc/terms.xhtml). After 12 months, it is available under a Creative Commons License (Attribution-NonCommercial 4.0 International), as described at http://creativecommons.org/licenses/by-nc/4.0/. |
spellingShingle | Article Ait-Bara, Soraya Clerté, Caroline Declerck, Nathalie Margeat, Emmanuel Competitive folding of RNA structures at a termination–antitermination site |
title | Competitive folding of RNA structures at a termination–antitermination site |
title_full | Competitive folding of RNA structures at a termination–antitermination site |
title_fullStr | Competitive folding of RNA structures at a termination–antitermination site |
title_full_unstemmed | Competitive folding of RNA structures at a termination–antitermination site |
title_short | Competitive folding of RNA structures at a termination–antitermination site |
title_sort | competitive folding of rna structures at a termination–antitermination site |
topic | Article |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5393181/ https://www.ncbi.nlm.nih.gov/pubmed/28235843 http://dx.doi.org/10.1261/rna.060178.116 |
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