GPCRs through the keyhole: the role of protein flexibility in ligand binding to β-adrenoceptors
G protein-coupled receptors (GPCRs) are proteins of pharmaceutical importance, with over 30% of all drugs in clinical use targeting them. Increasing numbers of X-ray crystal (XRC) structures of GPCRs offer a wealth of data relating to ligand binding. For the β-adrenoceptors (β-ARs), XRC structures a...
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Taylor and Francis
2016
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| Online Access: | https://eprints.nottingham.ac.uk/38626/ |
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| author | Emtage, Abigail L. Mistry, Shailesh N. Fischer, Peter M. Kellam, Barrie Laughton, Charles A. |
| author_facet | Emtage, Abigail L. Mistry, Shailesh N. Fischer, Peter M. Kellam, Barrie Laughton, Charles A. |
| author_sort | Emtage, Abigail L. |
| building | Nottingham Research Data Repository |
| collection | Online Access |
| description | G protein-coupled receptors (GPCRs) are proteins of pharmaceutical importance, with over 30% of all drugs in clinical use targeting them. Increasing numbers of X-ray crystal (XRC) structures of GPCRs offer a wealth of data relating to ligand binding. For the β-adrenoceptors (β-ARs), XRC structures are available for human β2- and turkey β1-subtypes, in complexes with a range of ligands. While these structures provide insight into the origins of ligand structure-activity relationships (SARs), questions remain. The ligands in all published complexed XRC structures lack extensive substitution, with no obvious way the ligand-binding site can accommodate β1-AR-selective antagonists with extended side-chains para- to the common aryloxypropanolamine pharmacophore. Using standard computational docking tools with such ligands generally returns poses that fail to explain known SARs. Application of our Active Site Pressurisation modelling method to β-AR XRC structures and homology models, however, reveals a dynamic area in the ligand-binding pocket that, through minor changes in amino acid side chain orientations, opens a fissure between transmembrane helices H4 and H5, exposing intra-membrane space. This fissure, which we term the “keyhole”, is ideally located to accommodate extended moieties present in many high-affinity β1-AR-selective ligands, allowing the rest of the ligand structure to adopt a canonical pose in the orthosteric binding site. We propose the keyhole may be a feature of both β1- and β2-ARs, but that subtle structural differences exist between the two, contributing to subtype-selectivity. This has consequences for the rational design of future generations of subtype-selective ligands for these therapeutically important targets. |
| first_indexed | 2025-11-14T19:35:31Z |
| format | Article |
| id | nottingham-38626 |
| institution | University of Nottingham Malaysia Campus |
| institution_category | Local University |
| last_indexed | 2025-11-14T19:35:31Z |
| publishDate | 2016 |
| publisher | Taylor and Francis |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | nottingham-386262020-05-04T18:06:43Z https://eprints.nottingham.ac.uk/38626/ GPCRs through the keyhole: the role of protein flexibility in ligand binding to β-adrenoceptors Emtage, Abigail L. Mistry, Shailesh N. Fischer, Peter M. Kellam, Barrie Laughton, Charles A. G protein-coupled receptors (GPCRs) are proteins of pharmaceutical importance, with over 30% of all drugs in clinical use targeting them. Increasing numbers of X-ray crystal (XRC) structures of GPCRs offer a wealth of data relating to ligand binding. For the β-adrenoceptors (β-ARs), XRC structures are available for human β2- and turkey β1-subtypes, in complexes with a range of ligands. While these structures provide insight into the origins of ligand structure-activity relationships (SARs), questions remain. The ligands in all published complexed XRC structures lack extensive substitution, with no obvious way the ligand-binding site can accommodate β1-AR-selective antagonists with extended side-chains para- to the common aryloxypropanolamine pharmacophore. Using standard computational docking tools with such ligands generally returns poses that fail to explain known SARs. Application of our Active Site Pressurisation modelling method to β-AR XRC structures and homology models, however, reveals a dynamic area in the ligand-binding pocket that, through minor changes in amino acid side chain orientations, opens a fissure between transmembrane helices H4 and H5, exposing intra-membrane space. This fissure, which we term the “keyhole”, is ideally located to accommodate extended moieties present in many high-affinity β1-AR-selective ligands, allowing the rest of the ligand structure to adopt a canonical pose in the orthosteric binding site. We propose the keyhole may be a feature of both β1- and β2-ARs, but that subtle structural differences exist between the two, contributing to subtype-selectivity. This has consequences for the rational design of future generations of subtype-selective ligands for these therapeutically important targets. Taylor and Francis 2016-08-17 Article PeerReviewed Emtage, Abigail L., Mistry, Shailesh N., Fischer, Peter M., Kellam, Barrie and Laughton, Charles A. (2016) GPCRs through the keyhole: the role of protein flexibility in ligand binding to β-adrenoceptors. Journal of Biomolecular Structure and Dynamics . pp. 1-16. ISSN 1538-0254 GPCRs beta adrenergic receptor modelling docking active site pressurisation molecular dynamics protein flexibility http://www.tandfonline.com/doi/full/10.1080/07391102.2016.1226197 doi:10.1080/07391102.2016.1226197 doi:10.1080/07391102.2016.1226197 |
| spellingShingle | GPCRs beta adrenergic receptor modelling docking active site pressurisation molecular dynamics protein flexibility Emtage, Abigail L. Mistry, Shailesh N. Fischer, Peter M. Kellam, Barrie Laughton, Charles A. GPCRs through the keyhole: the role of protein flexibility in ligand binding to β-adrenoceptors |
| title | GPCRs through the keyhole: the role of protein flexibility in ligand binding to β-adrenoceptors |
| title_full | GPCRs through the keyhole: the role of protein flexibility in ligand binding to β-adrenoceptors |
| title_fullStr | GPCRs through the keyhole: the role of protein flexibility in ligand binding to β-adrenoceptors |
| title_full_unstemmed | GPCRs through the keyhole: the role of protein flexibility in ligand binding to β-adrenoceptors |
| title_short | GPCRs through the keyhole: the role of protein flexibility in ligand binding to β-adrenoceptors |
| title_sort | gpcrs through the keyhole: the role of protein flexibility in ligand binding to β-adrenoceptors |
| topic | GPCRs beta adrenergic receptor modelling docking active site pressurisation molecular dynamics protein flexibility |
| url | https://eprints.nottingham.ac.uk/38626/ https://eprints.nottingham.ac.uk/38626/ https://eprints.nottingham.ac.uk/38626/ |