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Structural basis for ligand binding to the guanidine-II riboswitch
The guanidine-II riboswitch, also known as mini-ykkC, is a conserved mRNA element with more than 800 examples in bacteria. It consists of two stem–loops capped by identical, conserved tetraloops that are separated by a linker region of variable length and sequence. Like the guanidine-I riboswitch, i...
Autores principales: | , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
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Cold Spring Harbor Laboratory Press
2017
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5558903/ https://www.ncbi.nlm.nih.gov/pubmed/28600356 http://dx.doi.org/10.1261/rna.061804.117 |
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author | Reiss, Caroline W. Strobel, Scott A. |
author_facet | Reiss, Caroline W. Strobel, Scott A. |
author_sort | Reiss, Caroline W. |
collection | PubMed |
description | The guanidine-II riboswitch, also known as mini-ykkC, is a conserved mRNA element with more than 800 examples in bacteria. It consists of two stem–loops capped by identical, conserved tetraloops that are separated by a linker region of variable length and sequence. Like the guanidine-I riboswitch, it controls the expression of guanidine carboxylases and SugE-like genes. The guanidine-II riboswitch specifically binds free guanidinium cations and functions as a translationally controlled on-switch. Here we report the structure of a P2 stem–loop from the Pseudomonas aeruginosa guanidine-II riboswitch aptamer bound to guanidine at 1.57 Å resolution. The hairpins dimerize via the conserved tetraloop, which also contains the binding pocket. Two guanidinium molecules bind near the dimerization interface, one in each tetraloop. The guanidinium cation is engaged in extensive hydrogen bonding to the RNA. Contacts include the Hoogsteen face of a guanine base and three nonbridging phosphate oxygens. Cation–π interactions and ionic interactions also stabilize ligand binding. The guanidine-II riboswitch utilizes the same recognition strategies as the guanidine-I riboswitch while adopting an entirely different and much smaller RNA fold. |
format | Online Article Text |
id | pubmed-5558903 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2017 |
publisher | Cold Spring Harbor Laboratory Press |
record_format | MEDLINE/PubMed |
spelling | pubmed-55589032018-09-01 Structural basis for ligand binding to the guanidine-II riboswitch Reiss, Caroline W. Strobel, Scott A. RNA Report The guanidine-II riboswitch, also known as mini-ykkC, is a conserved mRNA element with more than 800 examples in bacteria. It consists of two stem–loops capped by identical, conserved tetraloops that are separated by a linker region of variable length and sequence. Like the guanidine-I riboswitch, it controls the expression of guanidine carboxylases and SugE-like genes. The guanidine-II riboswitch specifically binds free guanidinium cations and functions as a translationally controlled on-switch. Here we report the structure of a P2 stem–loop from the Pseudomonas aeruginosa guanidine-II riboswitch aptamer bound to guanidine at 1.57 Å resolution. The hairpins dimerize via the conserved tetraloop, which also contains the binding pocket. Two guanidinium molecules bind near the dimerization interface, one in each tetraloop. The guanidinium cation is engaged in extensive hydrogen bonding to the RNA. Contacts include the Hoogsteen face of a guanine base and three nonbridging phosphate oxygens. Cation–π interactions and ionic interactions also stabilize ligand binding. The guanidine-II riboswitch utilizes the same recognition strategies as the guanidine-I riboswitch while adopting an entirely different and much smaller RNA fold. Cold Spring Harbor Laboratory Press 2017-09 /pmc/articles/PMC5558903/ /pubmed/28600356 http://dx.doi.org/10.1261/rna.061804.117 Text en © 2017 Reiss and Strobel; 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 | Report Reiss, Caroline W. Strobel, Scott A. Structural basis for ligand binding to the guanidine-II riboswitch |
title | Structural basis for ligand binding to the guanidine-II riboswitch |
title_full | Structural basis for ligand binding to the guanidine-II riboswitch |
title_fullStr | Structural basis for ligand binding to the guanidine-II riboswitch |
title_full_unstemmed | Structural basis for ligand binding to the guanidine-II riboswitch |
title_short | Structural basis for ligand binding to the guanidine-II riboswitch |
title_sort | structural basis for ligand binding to the guanidine-ii riboswitch |
topic | Report |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5558903/ https://www.ncbi.nlm.nih.gov/pubmed/28600356 http://dx.doi.org/10.1261/rna.061804.117 |
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