Volume 6 Supplement 1
Dualsteric modulators of the M2 muscarinic acetylcholine receptor
© Bermudez and Wolber; licensee Chemistry Central Ltd. 2014
Published: 11 March 2014
G-protein coupled receptors (GPCRs) trigger multiple signal-switching mechanisms like binding of ß-arrestin proteins, activation of kinases and G-protein activation . The poor understanding of the conformational changes resulting in these activations is a major challenge for the design of specific GPCR modulating drugs. For the muscarinic M2 receptor, allosteric, orthosteric and dualsteric binding small molecules are available, which helps to elucidate multiple signaling roles [2–4]. The recently published crystal structure of the M2 muscarinic acetylcholine receptor (PDB: 3UON ) and mutational studies offer the possibility to rationalize and understand the binding of ligands to muscarinic acetylcholine receptors.
We present the results of extensive molecular dynamics simulations in combination with docking and 3D-pharmacophore analyses of known ligands (atropine and scopolamine) and their related dualsteric hybrid structures (JSW253, JSW257, JSW254 and JSW256). Insights into the flexibility of the allosteric binding pocket confirm earlier hypotheses: A comparison of dualsteric hybrid structures proves the crucial role of the tropane ring system for the arrangement of the allosteric part of the ligands. Whereas the extracellular loop 2 is engaged in the binding of the scopolamine-based hybrid structures, it plays a minor role for the binding of atropine-based dualsteric ligands. Orthosteric ligand binding was similar for all ligands and characterized by an essential electrostatic interaction and an aromatic cage.
- Jacoby E, et al: The 7TM G-protein-coupled receptor target family. Chemmedchem. 2006, 1: 760-782. 10.1002/cmdc.200600134.View ArticleGoogle Scholar
- Antony J, et al: Dualsteric GPCR targeting: a novel route to binding and signaling pathway selectivity. Faseb Journal. 2009, 23:Google Scholar
- Holzgrabe U, Mohr K: Allosteric modulators of ligand binding to muscarinic acetylcholine receptors. Drug Discov Today. 1998, 3:Google Scholar
- Jaeger D, et al: Allosteric small molecules unveil a role of an extracellular E2/transmembrane helix 7 junction for G protein-coupled receptor activation. J Biol Chem. 2007, 282:Google Scholar
- Haga K, et al: Structure of the human M2 muscarinic acetylcholine receptor bound to an antagonist. Nature. 2012, 482:Google Scholar
This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.