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Bouchouireb Z, Olivier-Jimenez D, Jaunet-Lahary T, Thany SH, Le Questel JY. Navigating the complexities of docking tools with nicotinic receptors and acetylcholine binding proteins in the realm of neonicotinoids. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2024; 281:116582. [PMID: 38905934 DOI: 10.1016/j.ecoenv.2024.116582] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2024] [Revised: 05/30/2024] [Accepted: 06/09/2024] [Indexed: 06/23/2024]
Abstract
Molecular docking, pivotal in predicting small-molecule ligand binding modes, struggles with accurately identifying binding conformations and affinities. This is particularly true for neonicotinoids, insecticides whose impacts on ecosystems require precise molecular interaction modeling. This study scrutinizes the effectiveness of prominent docking software (Ledock, ADFR, Autodock Vina, CDOCKER) in simulating interactions of environmental chemicals, especially neonicotinoid-like molecules with nicotinic acetylcholine receptors (nAChRs) and acetylcholine binding proteins (AChBPs). We aimed to assess the accuracy and reliability of these tools in reproducing crystallographic data, focusing on semi-flexible and flexible docking approaches. Our analysis identified Ledock as the most accurate in semi-flexible docking, while Autodock Vina with Vinardo scoring function proved most reliable. However, no software consistently excelled in both accuracy and reliability. Additionally, our evaluation revealed that none of the tools could establish a clear correlation between docking scores and experimental dissociation constants (Kd) for neonicotinoid-like compounds. In contrast, a strong correlation was found with drug-like compounds, bringing to light a bias in considered software towards pharmaceuticals, thus limiting their applicability to environmental chemicals. The comparison between semi-flexible and flexible docking revealed that the increased computational complexity of the latter did not result in enhanced accuracy. In fact, the higher computational cost of flexible docking with its lack of enhanced predictive accuracy, rendered this approach useless for this class of compounds. Conclusively, our findings emphasize the need for continued development of docking methodologies, particularly for environmental chemicals. This study not only illuminates current software capabilities but also underscores the urgency for advancements in computational molecular docking as it is a relevant tool to environmental sciences.
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Affiliation(s)
| | - Damien Olivier-Jimenez
- Leiden University Medical Center, Center for Proteomics and Metabolomics, Albinusdreef 2, Leiden 2333ZA, Netherlands
| | | | - Steeve H Thany
- Université d'Orléans, Physiology, Ecology and Environment (P2E) laboratory USC INRAE 1328, Orléans 45067, France; Institut universitaire de France (IUF), 1 rue Descartes 75005 Paris, France
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2
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O'Connor SM, Sleebs BE, Street IP, Flynn BL, Baell JB, Coles C, Quazi N, Paul D, Poiraud E, Huyard B, Wagner S, Andriambeloson E, de Souza EB. BNC210, a negative allosteric modulator of the alpha 7 nicotinic acetylcholine receptor, demonstrates anxiolytic- and antidepressant-like effects in rodents. Neuropharmacology 2024; 246:109836. [PMID: 38185416 DOI: 10.1016/j.neuropharm.2024.109836] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2023] [Revised: 12/31/2023] [Accepted: 01/02/2024] [Indexed: 01/09/2024]
Abstract
This work describes the characterization of BNC210 (6-[(2,3-dihydro-1H-inden-2-yl)amino]-1-ethyl-3-(4-morpholinylcarbonyl)-1,8-naphthyridin-4(1H)-one), a selective, small molecule, negative allosteric modulator (NAM) of α7 nicotinic acetylcholine receptors (α7 nAChR). With the aim to discover a non-sedating, anxiolytic compound, BNC210 was identified during phenotypic screening of a focused medicinal chemistry library using the mouse Light Dark (LD) box to evaluate anxiolytic-like activity and the mouse Open Field (OF) (dark) test to detect sedative and/or motor effects. BNC210 exhibited anxiolytic-like activity with no measurable sedative or motor effects. Electrophysiology showed that BNC210 did not induce α7 nAChR currents by itself but inhibited EC80 agonist-evoked currents in recombinant GH4C1 cell lines stably expressing the rat or human α7 nAChR. BNC210 was not active when tested on cell lines expressing other members of the cys-loop ligand-gated ion channel family. Screening over 400 other targets did not reveal any activity for BNC210 confirming its selectivity for α7 nAChR. Oral administration of BNC210 to male mice and rats in several tests of behavior related to anxiety- and stress- related disorders, demonstrated significant reduction of these behaviors over a broad therapeutic range up to 500 times the minimum effective dose. Further testing for potential adverse effects in suitable rat and mouse tests showed that BNC210 did not produce sedation, memory and motor impairment or physical dependence, symptoms associated with current anxiolytic therapeutics. These data suggest that allosteric inhibition of α7 nAChR function may represent a differentiated approach to treating anxiety- and stress- related disorders with an improved safety profile compared to current treatments.
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Affiliation(s)
| | - Brad E Sleebs
- The Walter and Eliza Hall Institute of Medical Research, Parkville, 3052, Australia; Department of Medical Biology, The University of Melbourne, Parkville, 3010, Australia
| | - Ian P Street
- The Walter and Eliza Hall Institute of Medical Research, Parkville, 3052, Australia; Department of Medical Biology, The University of Melbourne, Parkville, 3010, Australia; Children's Cancer Institute, School of Medicine and Health, UNSW, Randwick, Australia
| | - Bernard L Flynn
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Melbourne, Australia
| | - Jonathan B Baell
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Melbourne, Australia; The Walter and Eliza Hall Institute of Medical Research, Parkville, 3052, Australia
| | | | - Nurul Quazi
- The Walter and Eliza Hall Institute of Medical Research, Parkville, 3052, Australia
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Munafó JP, Biscussi B, Obiol D, Costabel M, Bouzat C, Murray AP, Antollini S. New Multitarget Molecules Derived from Caffeine as Potentiators of the Cholinergic System. ACS Chem Neurosci 2024; 15:994-1009. [PMID: 38407056 DOI: 10.1021/acschemneuro.3c00710] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/27/2024] Open
Abstract
Cholinergic deficit is a characteristic factor of several pathologies, such as myasthenia gravis, some types of congenital myasthenic syndromes, and Alzheimer's Disease. Two molecular targets for its treatment are acetylcholinesterase (AChE) and nicotinic acetylcholine receptor (nAChR). In previous studies, we found that caffeine behaves as a partial nAChR agonist and confirmed that it inhibits AChE. Here, we present new bifunctional caffeine derivatives consisting of a theophylline ring connected to amino groups by different linkers. All of them were more potent AChE inhibitors than caffeine. Furthermore, although some of them also activated muscle nAChR as partial agonists, not all of them stabilized nAChR in its desensitized conformation. To understand the molecular mechanism underlying these results, we performed docking studies on AChE and nAChR. The nAChR agonist behavior of the compounds depends on their accessory group, whereas their ability to stabilize the receptor in a desensitized state depends on the interactions of the linker at the binding site. Our results show that the new compounds can inhibit AChE and activate nAChR with greater potency than caffeine and provide further information on the modulation mechanisms of pharmacological targets for the design of novel therapeutic interventions in cholinergic deficit.
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Affiliation(s)
- Juan Pablo Munafó
- Instituto de Investigaciones Bioquímicas de Bahía Blanca, Departamento de Biología, Bioquímica y Farmacia, Universidad Nacional del Sur and Consejo Nacional de Investigaciones Científicas y Técnicas, Camino La Carrindanga km 7, Bahía Blanca 8000, Argentina
| | - Brunella Biscussi
- Instituto de Química del Sur, Departamento de Química, Universidad Nacional del Sur and Consejo Nacional de Investigaciones Científicas y Técnicas, Avda. Alem 1253, Bahía Blanca 8000, Argentina
| | - Diego Obiol
- Grupo de Biofísica, Instituto de Física del Sur, Departamento de Física, Universidad Nacional del Sur and Consejo Nacional de Investigaciones Científicas y Técnicas, Avda. Alem 1253, Bahía Blanca 8000, Argentina
| | - Marcelo Costabel
- Grupo de Biofísica, Instituto de Física del Sur, Departamento de Física, Universidad Nacional del Sur and Consejo Nacional de Investigaciones Científicas y Técnicas, Avda. Alem 1253, Bahía Blanca 8000, Argentina
| | - Cecilia Bouzat
- Instituto de Investigaciones Bioquímicas de Bahía Blanca, Departamento de Biología, Bioquímica y Farmacia, Universidad Nacional del Sur and Consejo Nacional de Investigaciones Científicas y Técnicas, Camino La Carrindanga km 7, Bahía Blanca 8000, Argentina
| | - Ana Paula Murray
- Instituto de Química del Sur, Departamento de Química, Universidad Nacional del Sur and Consejo Nacional de Investigaciones Científicas y Técnicas, Avda. Alem 1253, Bahía Blanca 8000, Argentina
| | - Silvia Antollini
- Instituto de Investigaciones Bioquímicas de Bahía Blanca, Departamento de Biología, Bioquímica y Farmacia, Universidad Nacional del Sur and Consejo Nacional de Investigaciones Científicas y Técnicas, Camino La Carrindanga km 7, Bahía Blanca 8000, Argentina
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FitzGerald EA, Vagrys D, Opassi G, Klein HF, Hamilton DJ, Talibov VO, Abramsson M, Moberg A, Lindgren MT, Holmgren C, Davis B, O'Brien P, Wijtmans M, Hubbard RE, de Esch IJP, Danielson UH. Multiplexed experimental strategies for fragment library screening against challenging drug targets using SPR biosensors. SLAS DISCOVERY : ADVANCING LIFE SCIENCES R & D 2024; 29:40-51. [PMID: 37714432 DOI: 10.1016/j.slasd.2023.09.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Revised: 09/01/2023] [Accepted: 09/05/2023] [Indexed: 09/17/2023]
Abstract
Surface plasmon resonance (SPR) biosensor methods are ideally suited for fragment-based lead discovery. However, generally applicable experimental procedures and detailed protocols are lacking, especially for structurally or physico-chemically challenging targets or when tool compounds are not available. Success depends on accounting for the features of both the target and the chemical library, purposely designing screening experiments for identification and validation of hits with desired specificity and mode-of-action, and availability of orthogonal methods capable of confirming fragment hits. The range of targets and libraries amenable to an SPR biosensor-based approach for identifying hits is considerably expanded by adopting multiplexed strategies, using multiple complementary surfaces or experimental conditions. Here we illustrate principles and multiplexed approaches for using flow-based SPR biosensor systems for screening fragment libraries of different sizes (90 and 1056 compounds) against a selection of challenging targets. It shows strategies for the identification of fragments interacting with 1) large and structurally dynamic targets, represented by acetyl choline binding protein (AChBP), a Cys-loop receptor ligand gated ion channel homologue, 2) targets in multi protein complexes, represented by lysine demethylase 1 and a corepressor (LSD1/CoREST), 3) structurally variable or unstable targets, represented by farnesyl pyrophosphate synthase (FPPS), 4) targets containing intrinsically disordered regions, represented by protein tyrosine phosphatase 1B (PTP1B), and 5) aggregation-prone proteins, represented by an engineered form of human tau (tau K18M). Practical considerations and procedures accounting for the characteristics of the proteins and libraries, and that increase robustness, sensitivity, throughput and versatility are highlighted. The study shows that the challenges for addressing these types of targets is not identification of potentially useful fragments per se, but establishing methods for their validation and evolution into leads.
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Affiliation(s)
- Edward A FitzGerald
- Department of Chemistry - BMC, Uppsala University, Uppsala, Sweden; Beactica Therapeutics AB, Virdings allé 2, Uppsala, Sweden
| | - Darius Vagrys
- Vernalis (R&D) Ltd., Granta Park, Great Abington, Cambridge, United Kingdom; YSBL, Department of Chemistry, University of York, York, United Kingdom
| | - Giulia Opassi
- Department of Chemistry - BMC, Uppsala University, Uppsala, Sweden
| | - Hanna F Klein
- Department of Chemistry, University of York, York, United Kingdom
| | - David J Hamilton
- Amsterdam Institute of Molecular and Life Sciences (AIMMS), Division of Medicinal Chemistry, Faculty of Sciences, Vrije Universiteit Amsterdam, De Boelelaan 1108, 1081 HZ, Amsterdam, The Netherlands
| | | | - Mia Abramsson
- Department of Chemistry - BMC, Uppsala University, Uppsala, Sweden
| | | | | | | | - Ben Davis
- Vernalis (R&D) Ltd., Granta Park, Great Abington, Cambridge, United Kingdom
| | - Peter O'Brien
- Department of Chemistry, University of York, York, United Kingdom
| | - Maikel Wijtmans
- Amsterdam Institute of Molecular and Life Sciences (AIMMS), Division of Medicinal Chemistry, Faculty of Sciences, Vrije Universiteit Amsterdam, De Boelelaan 1108, 1081 HZ, Amsterdam, The Netherlands
| | - Roderick E Hubbard
- Vernalis (R&D) Ltd., Granta Park, Great Abington, Cambridge, United Kingdom; YSBL, Department of Chemistry, University of York, York, United Kingdom
| | - Iwan J P de Esch
- Amsterdam Institute of Molecular and Life Sciences (AIMMS), Division of Medicinal Chemistry, Faculty of Sciences, Vrije Universiteit Amsterdam, De Boelelaan 1108, 1081 HZ, Amsterdam, The Netherlands
| | - U Helena Danielson
- Department of Chemistry - BMC, Uppsala University, Uppsala, Sweden; Science for Life Laboratory, Uppsala University, Uppsala, Sweden.
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Li Q, Nemecz Á, Aymé G, Dejean de la Bâtie G, Prevost MS, Pons S, Barilone N, Baachaoui R, Maskos U, Lafaye P, Corringer PJ. Generation of nanobodies acting as silent and positive allosteric modulators of the α7 nicotinic acetylcholine receptor. Cell Mol Life Sci 2023; 80:164. [PMID: 37231269 DOI: 10.1007/s00018-023-04779-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Revised: 03/28/2023] [Accepted: 04/07/2023] [Indexed: 05/27/2023]
Abstract
The α7 nicotinic acetylcholine receptor (nAChR), a potential drug target for treating cognitive disorders, mediates communication between neuronal and non-neuronal cells. Although many competitive antagonists, agonists, and partial-agonists have been found and synthesized, they have not led to effective therapeutic treatments. In this context, small molecules acting as positive allosteric modulators binding outside the orthosteric, acetylcholine, site have attracted considerable interest. Two single-domain antibody fragments, C4 and E3, against the extracellular domain of the human α7-nAChR were generated through alpaca immunization with cells expressing a human α7-nAChR/mouse 5-HT3A chimera, and are herein described. They bind to the α7-nAChR but not to the other major nAChR subtypes, α4β2 and α3β4. E3 acts as a slowly associating positive allosteric modulator, strongly potentiating the acetylcholine-elicited currents, while not precluding the desensitization of the receptor. An E3-E3 bivalent construct shows similar potentiating properties but displays very slow dissociation kinetics conferring quasi-irreversible properties. Whereas, C4 does not alter the receptor function, but fully inhibits the E3-evoked potentiation, showing it is a silent allosteric modulator competing with E3 binding. Both nanobodies do not compete with α-bungarotoxin, localizing at an allosteric extracellular binding site away from the orthosteric site. The functional differences of each nanobody, as well as the alteration of functional properties through nanobody modifications indicate the importance of this extracellular site. The nanobodies will be useful for pharmacological and structural investigations; moreover, they, along with the extracellular site, have a direct potential for clinical applications.
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Affiliation(s)
- Qimeng Li
- Institut Pasteur, Université Paris Cité, CNRS UMR 3571, Channel-Receptors Unit, Paris, France
- Institut Pasteur, Université Paris Cité, CNRS UMR 3528, Antibody Engineering Platform, Paris, France
- Lanzhou Institute of Biological Product Co., Lanzhou, China
- Sorbonne Université, Collège Doctoral, Paris, France
| | - Ákos Nemecz
- Institut Pasteur, Université Paris Cité, CNRS UMR 3571, Channel-Receptors Unit, Paris, France.
| | - Gabriel Aymé
- Institut Pasteur, Université Paris Cité, CNRS UMR 3528, Antibody Engineering Platform, Paris, France.
| | | | - Marie S Prevost
- Institut Pasteur, Université Paris Cité, CNRS UMR 3571, Channel-Receptors Unit, Paris, France
| | - Stéphanie Pons
- Institut Pasteur, Université Paris Cité, CNRS UMR 3571, Integrative Neurobiology of Cholinergic Systems Unit, Paris, France
| | - Nathalie Barilone
- Institut Pasteur, Université Paris Cité, CNRS UMR 3571, Channel-Receptors Unit, Paris, France
| | - Rayen Baachaoui
- Institut Pasteur, Université Paris Cité, CNRS UMR 3571, Channel-Receptors Unit, Paris, France
- Institut Pasteur, Université Paris Cité, CNRS UMR 3528, Antibody Engineering Platform, Paris, France
| | - Uwe Maskos
- Institut Pasteur, Université Paris Cité, CNRS UMR 3571, Integrative Neurobiology of Cholinergic Systems Unit, Paris, France
| | - Pierre Lafaye
- Institut Pasteur, Université Paris Cité, CNRS UMR 3528, Antibody Engineering Platform, Paris, France
| | - Pierre-Jean Corringer
- Institut Pasteur, Université Paris Cité, CNRS UMR 3571, Channel-Receptors Unit, Paris, France.
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Sanders VR, Millar NS. Potentiation and allosteric agonist activation of α7 nicotinic acetylcholine receptors: binding sites and hypotheses. Pharmacol Res 2023; 191:106759. [PMID: 37023990 DOI: 10.1016/j.phrs.2023.106759] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Revised: 03/27/2023] [Accepted: 03/30/2023] [Indexed: 04/07/2023]
Abstract
Considerable progress has been made in recent years towards the identification and characterisation of novel subtype-selective modulators of nicotinic acetylcholine receptors (nAChRs). In particular, this has focussed on modulators of α7 nAChRs, a nAChR subtype that has been identified as a target for drug discovery in connection with a range of potential therapeutic applications. This review focusses upon α7-selective modulators that bind to receptor sites other than the extracellular 'orthosteric' agonist binding site for the endogenous agonist acetylcholine (ACh). Such compounds include those that are able to potentiate responses evoked by orthosteric agonists such as ACh (positive allosteric modulators; PAMs) and those that are able to activate α7 nAChRs by direct allosteric activation in the absence of an orthosteric agonist (allosteric agonists or 'ago-PAMs'). There has been considerable debate about the mechanism of action of α7-selective PAMs and allosteric agonists, much of which has centred around identifying the location of their binding sites on α7 nAChRs. Based on a variety of experimental evidence, including recent structural data, there is now clear evidence indicating that at least some α7-selective PAMs bind to an inter-subunit site located in the transmembrane domain. In contrast, there are differing hypotheses about the site or sites at which allosteric agonists bind to α7 nAChRs. It will be argued that the available evidence supports the conclusion that direct allosteric activation by allosteric agonists/ago-PAMs occurs via the same inter-subunit transmembrane site that has been identified for several α7-selective PAMs.
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Affiliation(s)
- Victoria R Sanders
- Division of Biosciences, University College London, London WC1E 6BT, United Kingdom
| | - Neil S Millar
- Division of Biosciences, University College London, London WC1E 6BT, United Kingdom.
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Leitzke M. Is the post-COVID-19 syndrome a severe impairment of acetylcholine-orchestrated neuromodulation that responds to nicotine administration? Bioelectron Med 2023; 9:2. [PMID: 36650574 PMCID: PMC9845100 DOI: 10.1186/s42234-023-00104-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Accepted: 12/30/2022] [Indexed: 01/19/2023] Open
Abstract
Following a SARS-CoV-2 infection, many individuals suffer from post-COVID-19 syndrome. It makes them unable to proceed with common everyday activities due to weakness, memory lapses, pain, dyspnea and other unspecific physical complaints. Several investigators could demonstrate that the SARS-CoV-2 related spike glycoprotein (SGP) attaches not only to ACE-2 receptors but also shows DNA sections highly affine to nicotinic acetylcholine receptors (nAChRs). The nAChR is the principal structure of cholinergic neuromodulation and is responsible for coordinated neuronal network interaction. Non-intrinsic viral nAChR attachment compromises integrative interneuronal communication substantially. This explains the cognitive, neuromuscular and mood impairment, as well as the vegetative symptoms, characterizing post-COVID-19 syndrome. The agonist ligand nicotine shows an up to 30-fold higher affinity to nACHRs than acetylcholine (ACh). We therefore hypothesize that this molecule could displace the virus from nAChR attachment and pave the way for unimpaired cholinergic signal transmission. Treating several individuals suffering from post-COVID-19 syndrome with a nicotine patch application, we witnessed improvements ranging from immediate and substantial to complete remission in a matter of days.
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Affiliation(s)
- Marco Leitzke
- Department of Anesthesiology, Helios Clinics, Colditzer Straße 48, 04703, Leisnig, Germany.
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Ho TNT, Abraham N, Lewis RJ. Unravelling the allosteric binding mode of αD-VxXXB at nicotinic acetylcholine receptors. Front Pharmacol 2023; 14:1170514. [PMID: 37124228 PMCID: PMC10133702 DOI: 10.3389/fphar.2023.1170514] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Accepted: 03/30/2023] [Indexed: 05/02/2023] Open
Abstract
αD-conotoxins are 11 kDa homodimers that potently inhibit nicotinic acetylcholine receptors (nAChRs) through a non-competitive (allosteric) mechanism. In this study, we describe the allosteric binding mode of the granulin-like C-terminal (CTD) of VxXXB bound to Lymnea stagnalis acetylcholine binding protein (Ls-AChBP), a soluble homologue of the extracellular ligand-binding domain of nAChRs. This co-crystal complex revealed a novel allosteric binding site for nAChR antagonists outside the C-loop that caps the orthosteric site defined by the nAChR agonist nicotine and the antagonist epibatidine. Mutational and docking studies on Ls-AChBP supported a two-site binding mode for full-length VxXXB, with the first CTD binding site located outside the C-loop as seen in the co-crystal complex, with a second CTD binding site located near the N-terminal end of the adjacent subunit of AChBP. These results provide new structural insight into a novel allosteric mechanism of nAChR inhibition and define the cooperative binding mode of the N-terminal domain linked granulin core domains of αD-conotoxins.
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Zhao M, Ma Y, Xin J, Cao C, Wang J. Detection of differential selection pressure and functional-specific sites in subunits of vertebrate neuronal nicotinic acetylcholine receptors. J Biomol Struct Dyn 2022; 40:13161-13170. [PMID: 34596010 DOI: 10.1080/07391102.2021.1982772] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The nicotinic acetylcholine receptors (nAChR) are made of subunits evolved from a common ancestor. Despite the similarity in their sequences and structures, the properties of these subunits vary significantly. Thus, identifying the evolution features and function-related sites specific to each subunit is essential for understanding the characteristics of the subunits and the receptors assembled by them. In this study, we examined the sequence features of the nine neuronal nAChRs subunits from representative vertebrate species. Analysis revealed that all the subunits were subject to strong purifying selection in evolution, and each was under a unique pattern of selection pressures. At the same time, the functional constraints were not uniform within each subunit, with different domains in the molecule being subject to different selection pressures. We also detected potential positive selection events in the subunits or subunit clusters, and identified the sites might be associated with the function specificity of each subunit. Furthermore, positive selection at some domains might contribute to the diversity of subunit function; for example, the β9 strand might be related to the agonist specificity of α subunit in heteromeric receptor and β4-β5 linker could be involved in Ca2+ permeability. Subunits α7, α4 and β2 subunits possess a strong adaptability in vertebrates. Our results highlighted the importance of tracking functional differentiation in protein sequence underlying functional properties of nAChRs. In summary, our work may provide clues on understanding the diversity and the function specificity of the nAChR subunits, as well as the receptors co-assembled by them.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Mengwen Zhao
- School of Biomedical Engineering, Tianjin Medical University, Tianjin, China
| | - Yuequn Ma
- School of Biomedical Engineering, Tianjin Medical University, Tianjin, China
| | - Juncai Xin
- School of Biomedical Engineering, Tianjin Medical University, Tianjin, China
| | - Changying Cao
- School of Biomedical Engineering, Tianjin Medical University, Tianjin, China
| | - Ju Wang
- School of Biomedical Engineering, Tianjin Medical University, Tianjin, China
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Batista VS, Gonçalves AM, Nascimento-Júnior NM. Pharmacophore Mapping Combined with dbCICA Reveal New Structural Features for the Development of Novel Ligands Targeting α4β2 and α7 Nicotinic Acetylcholine Receptors. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27238236. [PMID: 36500328 PMCID: PMC9735964 DOI: 10.3390/molecules27238236] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Revised: 11/04/2022] [Accepted: 11/10/2022] [Indexed: 11/29/2022]
Abstract
The neuronal nicotinic acetylcholine receptors (nAChRs) belong to the ligand-gated ion channel (GLIC) group, presenting a crucial role in several biological processes and neuronal disorders. The α4β2 and α7 nAChRs are the most abundant in the central nervous system (CNS), being involved in challenging diseases such as epilepsy, Alzheimer's disease, schizophrenia, and anxiety disorder, as well as alcohol and nicotine dependencies. In addition, in silico-based strategies may contribute to revealing new insights into drug design and virtual screening to find new drug candidates to treat CNS disorders. In this context, the pharmacophore maps were constructed and validated for the orthosteric sites of α4β2 and α7 nAChRs, through a docking-based Comparative Intermolecular Contacts Analysis (dbCICA). In this sense, bioactive ligands were retrieved from the literature for each receptor. A molecular docking protocol was developed for all ligands in both receptors by using GOLD software, considering GoldScore, ChemScore, ASP, and ChemPLP scoring functions. Output GOLD results were post-processed through dbCICA to identify critical contacts involved in protein-ligand interactions. Moreover, Crossminer software was used to construct a pharmacophoric map based on the most well-behaved ligands and negative contacts from the dbCICA model for each receptor. Both pharmacophore maps were validated by using a ROC curve. The results revealed important features for the ligands, such as the presence of hydrophobic regions, a planar ring, and hydrogen bond donor and acceptor atoms for α4β2. Parallelly, a non-planar ring region was identified for α7. These results can enable fragment-based drug design (FBDD) strategies, such as fragment growing, linking, and merging, allowing an increase in the activity of known fragments. Thus, our results can contribute to a further understanding of structural subunits presenting the potential for key ligand-receptor interactions, favoring the search in molecular databases and the design of novel ligands.
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Affiliation(s)
- Victor S. Batista
- Laboratory of Medicinal Chemistry, Organic Synthesis and Molecular Modeling (LaQMedSOMM), Department of Biochemistry and Organic Chemistry, Institute of Chemistry, São Paulo State University (Unesp), Rua Professor Francisco Degni, 55, Jardim Quitandinha, Araraquara 14800-060, SP, Brazil
| | - Adriano Marques Gonçalves
- Laboratory of Medicinal Chemistry, Organic Synthesis and Molecular Modeling (LaQMedSOMM), Department of Biochemistry and Organic Chemistry, Institute of Chemistry, São Paulo State University (Unesp), Rua Professor Francisco Degni, 55, Jardim Quitandinha, Araraquara 14800-060, SP, Brazil
- Department of Biological and Health Sciences, University of Araraquara (Uniara), Rua Carlos Gomes, 1217, Centro, Araraquara 14801-340, SP, Brazil
| | - Nailton M. Nascimento-Júnior
- Laboratory of Medicinal Chemistry, Organic Synthesis and Molecular Modeling (LaQMedSOMM), Department of Biochemistry and Organic Chemistry, Institute of Chemistry, São Paulo State University (Unesp), Rua Professor Francisco Degni, 55, Jardim Quitandinha, Araraquara 14800-060, SP, Brazil
- Correspondence:
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Kaiser J, Gertzen CG, Bernauer T, Höfner G, Niessen KV, Seeger T, Paintner FF, Wanner KT, Worek F, Thiermann H, Gohlke H. A novel binding site in the nicotinic acetylcholine receptor for MB327 can explain its allosteric modulation relevant for organophosphorus-poisoning treatment. Toxicol Lett 2022; 373:160-171. [DOI: 10.1016/j.toxlet.2022.11.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2022] [Accepted: 11/25/2022] [Indexed: 11/27/2022]
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12
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Chrestia JF, Oliveira AS, Mulholland AJ, Gallagher T, Bermúdez I, Bouzat C. A Functional Interaction Between Y674-R685 Region of the SARS-CoV-2 Spike Protein and the Human α7 Nicotinic Receptor. Mol Neurobiol 2022; 59:6076-6090. [PMID: 35859025 PMCID: PMC9299415 DOI: 10.1007/s12035-022-02947-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Accepted: 06/28/2022] [Indexed: 11/15/2022]
Abstract
The α7 nicotinic acetylcholine receptor (nAChR) is present in neuronal and non-neuronal cells and has anti-inflammatory actions. Molecular dynamics simulations suggested that α7 nAChR interacts with a region of the SARS-CoV-2 spike protein (S), and a potential contribution of nAChRs to COVID-19 pathophysiology has been proposed. We applied whole-cell and single-channel recordings to determine whether a peptide corresponding to the Y674-R685 region of the S protein can directly affect α7 nAChR function. The S fragment exerts a dual effect on α7. It activates α7 nAChRs in the presence of positive allosteric modulators, in line with our previous molecular dynamics simulations showing favourable binding of this accessible region of the S protein to the nAChR agonist binding site. The S fragment also exerts a negative modulation of α7, which is evidenced by a profound concentration-dependent decrease in the durations of openings and activation episodes of potentiated channels and in the amplitude of macroscopic responses elicited by ACh. Our study identifies a potential functional interaction between α7 nAChR and a region of the S protein, thus providing molecular foundations for further exploring the involvement of nAChRs in COVID-19 pathophysiology.
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Affiliation(s)
- Juan Facundo Chrestia
- Instituto de Investigaciones Bioquímicas de Bahía Blanca, Departamento de Biología, Bioquímica y Farmacia, Universidad Nacional del Sur-Consejo Nacional de Investigaciones Científicas Y Técnicas (CONICET), Camino La Carrindanga Km 7-8000, Bahía Blanca, Argentina
| | - Ana Sofia Oliveira
- Centre for Computational Chemistry, School of Chemistry, University of Bristol, Bristol, BS8 1TS, UK
| | - Adrian J Mulholland
- Centre for Computational Chemistry, School of Chemistry, University of Bristol, Bristol, BS8 1TS, UK
| | | | - Isabel Bermúdez
- Department of Biological and Medical Sciences, Oxford Brookes University, Oxford, OX3 0BP, UK.
| | - Cecilia Bouzat
- Instituto de Investigaciones Bioquímicas de Bahía Blanca, Departamento de Biología, Bioquímica y Farmacia, Universidad Nacional del Sur-Consejo Nacional de Investigaciones Científicas Y Técnicas (CONICET), Camino La Carrindanga Km 7-8000, Bahía Blanca, Argentina.
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13
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Fabiani C, Biscussi B, Munafo JP, Murray AP, Corradi J, Antollini SS. NEW SYNTHETIC CAFFEINE ANALOGS AS MODULATORS OF THE CHOLINERGIC SYSTEM. Mol Pharmacol 2021; 101:154-167. [PMID: 34969831 DOI: 10.1124/molpharm.121.000415] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Accepted: 12/26/2021] [Indexed: 11/22/2022] Open
Abstract
Alzheimer's disease (AD) is a multifactorial neurodegenerative disorder. Since cholinergic deficit is a major factor in this disease, two molecular targets for its treatment are the acetylcholinesterase (AChE) and the nicotinic acetylcholine receptors (nAChRs). Given that caffeine is a natural compound that behaves as an AChE inhibitor and as a partial agonist of nAChRs, the aim of this work was to synthetize more potent bifunctional caffeine analogs that modulate these two molecular targets. To this end, a theophylline structure was connected to a pyrrolidine structure through a methylene chain of different lengths (3 to 7 carbon atoms) to give compounds 7-11 All caffeine derivatives inhibited the AChE, of which compound 11 showed the strongest effect. Electrophysiological studies showed that all compounds behave as agonists of the muscle and the neuronal α7 nAChR with greater potency than caffeine. To explore if the different analogs could affect the nAChR conformational state, the nAChR conformational-sensitive probe crystal violet (CrV) was used. Compounds 9 and 10 conduced the nAChR to a different conformational state comparable with a control nAChR desensitized state. Finally, molecular docking experiments showed that all derivatives interacted with both the catalytic and anionic sites of AChE and with the orthosteric binding site of the nAChR. Thus, the new synthetized compounds can inhibit the AChE and activate muscle and α7 nAChRs with greater potency than caffeine, which suggests that they could be useful leaders for the development of new therapies for the treatment of different neurological diseases. Significance Statement In this work we synthetized caffeine derivatives which can inhibit the AChE and activate both muscle and α7 nAChRs with higher potency than caffeine. These analogs can be divided into two groups: a non-desensitizing and a desensitizing nAChR group. From the nAChR-non desensitizing group, we propose compound 11 as the most interesting analog for further studies since it inhibits AChE with the highest potency and activates the nAChRs in the picomolar range without inducing receptor desensitization.
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Affiliation(s)
- Camila Fabiani
- Instituto de Investigaciones Bioquímicas de Bahía Blanca, Departamento de Biología, Bioquímica y Farmacia, Universidad Nacional del Sur y Consejo Nacional de Investigaciones Científicas y Técnicas, Camino La Carrindanga km 7, Argentina
| | - Brunella Biscussi
- Instituto de Química del Sur, Departamento de Química, Universidad Nacional del Sur y Consejo Nacional de Investigaciones Científicas y Técnicas, Av. Alem 1253, Argentina
| | - Juan Pablo Munafo
- Instituto de Investigaciones Bioquímicas de Bahía Blanca, Departamento de Biología, Bioquímica y Farmacia, Universidad Nacional del Sur y Consejo Nacional de Investigaciones Científicas y Técnicas, Camino La Carrindanga km 7, Argentina
| | - Ana Paula Murray
- Instituto de Química del Sur, Departamento de Química, Universidad Nacional del Sur y Consejo Nacional de Investigaciones Científicas y Técnicas, Av. Alem 1253, Argentina
| | - Jeremias Corradi
- Instituto de Investigaciones Bioquímicas de Bahía Blanca, Departamento de Biología, Bioquímica y Farmacia, Universidad Nacional del Sur y Consejo Nacional de Investigaciones Científicas y Técnicas, Camino La Carrindanga km 7, Argentina
| | - Silvia Susana Antollini
- Instituto de Investigaciones Bioquímicas de Bahía Blanca, Departamento de Biología, Bioquímica y Farmacia, Universidad Nacional del Sur y Consejo Nacional de Investigaciones Científicas y Técnicas, Camino La Carrindanga km 7, Argentina
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14
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Bavo F, de-Jong H, Petersen J, Falk-Petersen CB, Löffler R, Sparrow E, Rostrup F, Eliasen JN, Wilhelmsen KS, Barslund K, Bundgaard C, Nielsen B, Kristiansen U, Wellendorph P, Bogdanov Y, Frølund B. Structure-Activity Studies of 3,9-Diazaspiro[5.5]undecane-Based γ-Aminobutyric Acid Type A Receptor Antagonists with Immunomodulatory Effect. J Med Chem 2021; 64:17795-17812. [PMID: 34908407 DOI: 10.1021/acs.jmedchem.1c00290] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The 3,9-diazaspiro[5.5]undecane-based compounds 2027 and 018 have previously been reported to be potent competitive γ-aminobutyric acid type A receptor (GABAAR) antagonists showing low cellular membrane permeability. Given the emerging peripheral application of GABAAR ligands, we hypothesize 2027 analogs as promising lead structures for peripheral GABAAR inhibition. We herein report a study on the structural determinants of 2027 in order to suggest a potential binding mode as a basis for rational design. The study identified the importance of the spirocyclic benzamide, compensating for the conventional acidic moiety, for GABAAR ligands. The structurally simplified m-methylphenyl analog 1e displayed binding affinity in the high-nanomolar range (Ki = 180 nM) and was superior to 2027 and 018 regarding selectivity for the extrasynaptic α4βδ subtype versus the α1- and α2- containing subtypes. Importantly, 1e was shown to efficiently rescue inhibition of T cell proliferation, providing a platform to explore the immunomodulatory potential for this class of compounds.
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Affiliation(s)
- Francesco Bavo
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
| | - Heleen de-Jong
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
| | - Jonas Petersen
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B, DK-2200 Copenhagen, Denmark
| | - Christina Birkedahl Falk-Petersen
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
| | - Rebekka Löffler
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
| | - Emma Sparrow
- Antibody and Vaccine Group, Centre for Cancer Immunology, MP127, University of Southampton Faculty of Medicine, Southampton, Hants SO16 6YD, United Kingdom
| | - Frederik Rostrup
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
| | - Jannik Nicklas Eliasen
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
| | - Kristine S Wilhelmsen
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
| | - Kasper Barslund
- Translational DMPK, H. Lundbeck A/S, Ottiliavej 9, 2500 Valby, Denmark
| | | | - Birgitte Nielsen
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
| | - Uffe Kristiansen
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
| | - Petrine Wellendorph
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
| | - Yury Bogdanov
- Antibody and Vaccine Group, Centre for Cancer Immunology, MP127, University of Southampton Faculty of Medicine, Southampton, Hants SO16 6YD, United Kingdom
| | - Bente Frølund
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
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15
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Gulsevin A, Papke RL, Stokes C, Tran HNT, Jin AH, Vetter I, Meiler J. The Allosteric Activation of α7 nAChR by α-Conotoxin MrIC Is Modified by Mutations at the Vestibular Site. Toxins (Basel) 2021; 13:toxins13080555. [PMID: 34437426 PMCID: PMC8402416 DOI: 10.3390/toxins13080555] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Revised: 08/02/2021] [Accepted: 08/09/2021] [Indexed: 12/18/2022] Open
Abstract
α-conotoxins are 13–19 amino acid toxin peptides that bind various nicotinic acetylcholine receptor (nAChR) subtypes. α-conotoxin Mr1.7c (MrIC) is a 17 amino acid peptide that targets α7 nAChR. Although MrIC has no activating effect on α7 nAChR when applied by itself, it evokes a large response when co-applied with the type II positive allosteric modulator PNU-120596, which potentiates the α7 nAChR response by recovering it from a desensitized state. A lack of standalone activity, despite activation upon co-application with a positive allosteric modulator, was previously observed for molecules that bind to an extracellular domain allosteric activation (AA) site at the vestibule of the receptor. We hypothesized that MrIC may activate α7 nAChR allosterically through this site. We ran voltage-clamp electrophysiology experiments and in silico peptide docking calculations in order to gather evidence in support of α7 nAChR activation by MrIC through the AA site. The experiments with the wild-type α7 nAChR supported an allosteric mode of action, which was confirmed by the significantly increased MrIC + PNU-120596 responses of three α7 nAChR AA site mutants that were designed in silico to improve MrIC binding. Overall, our results shed light on the allosteric activation of α7 nAChR by MrIC and suggest the involvement of the AA site.
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Affiliation(s)
- Alican Gulsevin
- Center for Structural Biology, Department of Chemistry, Vanderbilt University, Nashville, TN 37212, USA;
- Correspondence:
| | - Roger L. Papke
- Department of Pharmacology and Therapeutics, College of Medicine, University of Florida, Gainesville, FL 32610, USA; (R.L.P.); (C.S.)
| | - Clare Stokes
- Department of Pharmacology and Therapeutics, College of Medicine, University of Florida, Gainesville, FL 32610, USA; (R.L.P.); (C.S.)
| | - Hue N. T. Tran
- Institute for Molecular Bioscience, The University of Queensland, St Lucia, QLD 4072, Australia; (H.N.T.T.); (A.H.J.); (I.V.)
| | - Aihua H. Jin
- Institute for Molecular Bioscience, The University of Queensland, St Lucia, QLD 4072, Australia; (H.N.T.T.); (A.H.J.); (I.V.)
| | - Irina Vetter
- Institute for Molecular Bioscience, The University of Queensland, St Lucia, QLD 4072, Australia; (H.N.T.T.); (A.H.J.); (I.V.)
- School of Pharmacy, The University of Queensland, Woolloongabba, QLD 4102, Australia
| | - Jens Meiler
- Center for Structural Biology, Department of Chemistry, Vanderbilt University, Nashville, TN 37212, USA;
- Institute for Drug Discovery, Leipzig University Medical School, 04103 Leipzig, Germany
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16
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Yang M, Carter S, Parmar S, Bume DD, Calabrese DR, Liang X, Yazdani K, Xu M, Liu Z, Thiele CJ, Schneekloth JS. Targeting a noncanonical, hairpin-containing G-quadruplex structure from the MYCN gene. Nucleic Acids Res 2021; 49:7856-7869. [PMID: 34289065 DOI: 10.1093/nar/gkab594] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Revised: 06/10/2021] [Accepted: 07/20/2021] [Indexed: 11/12/2022] Open
Abstract
The MYCN gene encodes the transcription factor N-Myc, a driver of neuroblastoma (NB). Targeting G-quadruplexes (G4s) with small molecules is attractive strategy to control the expression of undruggable proteins such as N-Myc. However, selective binders to G4s are challenging to identify due to the structural similarity of many G4s. Here, we report the discovery of a small molecule ligand (4) that targets the noncanonical, hairpin containing G4 structure found in the MYCN gene using small molecule microarrays (SMMs). Unlike many G4 binders, the compound was found to bind to a pocket at the base of the hairpin region of the MYCN G4. This compound stabilizes the G4 and has affinity of 3.5 ± 1.6 μM. Moreover, an improved analog, MY-8, suppressed levels of both MYCN and MYCNOS (a lncRNA embedded within the MYCN gene) in NBEB neuroblastoma cells. This work indicates that the approach of targeting complex, hybrid G4 structures that exist throughout the human genome may be an applicable strategy to achieve selectivity for targeting disease-relevant genes including protein coding (MYCN) as well as non-coding (MYCNOS) gene products.
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Affiliation(s)
- Mo Yang
- Chemical Biology Laboratory, Center for Cancer Research, National Cancer Institute, Frederick, MD 21702-1201, USA
| | - Sakereh Carter
- Pediatric Oncology Branch, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892-1928, USA
| | - Shaifaly Parmar
- Chemical Biology Laboratory, Center for Cancer Research, National Cancer Institute, Frederick, MD 21702-1201, USA
| | - Desta D Bume
- Chemical Biology Laboratory, Center for Cancer Research, National Cancer Institute, Frederick, MD 21702-1201, USA
| | - David R Calabrese
- Chemical Biology Laboratory, Center for Cancer Research, National Cancer Institute, Frederick, MD 21702-1201, USA
| | - Xiao Liang
- Chemical Biology Laboratory, Center for Cancer Research, National Cancer Institute, Frederick, MD 21702-1201, USA
| | - Kamyar Yazdani
- Chemical Biology Laboratory, Center for Cancer Research, National Cancer Institute, Frederick, MD 21702-1201, USA
| | - Man Xu
- Pediatric Oncology Branch, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892-1928, USA
| | - Zhihui Liu
- Pediatric Oncology Branch, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892-1928, USA
| | - Carol J Thiele
- Pediatric Oncology Branch, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892-1928, USA
| | - John S Schneekloth
- Chemical Biology Laboratory, Center for Cancer Research, National Cancer Institute, Frederick, MD 21702-1201, USA
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17
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Elephants in the Dark: Insights and Incongruities in Pentameric Ligand-gated Ion Channel Models. J Mol Biol 2021; 433:167128. [PMID: 34224751 DOI: 10.1016/j.jmb.2021.167128] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2021] [Revised: 06/25/2021] [Accepted: 06/25/2021] [Indexed: 02/06/2023]
Abstract
The superfamily of pentameric ligand-gated ion channels (pLGICs) comprises key players in electrochemical signal transduction across evolution, including historic model systems for receptor allostery and targets for drug development. Accordingly, structural studies of these channels have steadily increased, and now approach 250 depositions in the protein data bank. This review contextualizes currently available structures in the pLGIC family, focusing on morphology, ligand binding, and gating in three model subfamilies: the prokaryotic channel GLIC, the cation-selective nicotinic acetylcholine receptor, and the anion-selective glycine receptor. Common themes include the challenging process of capturing and annotating channels in distinct functional states; partially conserved gating mechanisms, including remodeling at the extracellular/transmembrane-domain interface; and diversity beyond the protein level, arising from posttranslational modifications, ligands, lipids, and signaling partners. Interpreting pLGIC structures can be compared to describing an elephant in the dark, relying on touch alone to comprehend the many parts of a monumental beast: each structure represents a snapshot in time under specific experimental conditions, which must be integrated with further structure, function, and simulations data to build a comprehensive model, and understand how one channel may fundamentally differ from another.
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18
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Alwassil OI, Abdrakhmanova GR, Dukat M. Computational analysis of non-competitive antagonist arylguanidine-α7 nAChR complexes. J Mol Graph Model 2021; 107:107943. [PMID: 34058639 DOI: 10.1016/j.jmgm.2021.107943] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Revised: 04/07/2021] [Accepted: 05/11/2021] [Indexed: 10/21/2022]
Abstract
meta-Chlorophenylguanidine (1) is a non-competitive α7 nicotinic acetylcholine receptor (nAChR) antagonist. Here we examined the hydrogen bond donor role of the anilinic N1-H on the inhibitory effect of 1 by preparing its N1-CH3 counterpart 2. Analog 2 was found to be at least as potent as 1 as a non-competitive α7 nAChR antagonist in a patch-clamp assay. To establish a structural basis for the mode of interaction of guanidines 1 and 2, we generated 100 homology models of the hα7 nAChR. This was followed by Connolly surface (SYBYL-X2.1) and blind docking (AutoDock 4.1) studies to identify eight possible binding pockets, two of which were supported by empirical data and employed in our docking studies. The optimized model-ligand complexes were analyzed using a Hydropathic INTeractions (HINT) analysis in order to compare and contrast different binding pockets and modes. We identified a potential allosteric binding site and distinct rotameric binding modes for 1 and 2 at α7 nAChRs. These differences in the binding orientations minimized the importance of an anilinic NH function for the antagonist activity at nACh receptors.
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Affiliation(s)
- Osama I Alwassil
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, P.O. Box 980540, Richmond, VA, 23298-540, USA
| | - Galya R Abdrakhmanova
- Department of Pharmacology and Toxicology, School of Medicine, Virginia Commonwealth University, P.O. Box 980524, Richmond, VA, 23298, USA
| | - Małgorzata Dukat
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, P.O. Box 980540, Richmond, VA, 23298-540, USA.
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19
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Pismataro MC, Horenstein NA, Stokes C, Dallanoce C, Thakur GA, Papke RL. Stable desensitization of α 7 nicotinic acetylcholine receptors by NS6740 requires interaction with S36 in the orthosteric agonist binding site. Eur J Pharmacol 2021; 905:174179. [PMID: 34004208 DOI: 10.1016/j.ejphar.2021.174179] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Revised: 05/05/2021] [Accepted: 05/12/2021] [Indexed: 01/09/2023]
Abstract
NS6740 is an α7 nicotinic acetylcholine receptor-selective partial agonist with low efficacy for channel activation, capable of promoting the stable conversion of the receptors to nonconducting (desensitized) states that can be reactivated with the application of positive allosteric modulators (PAMs). In spite of its low efficacy for channel activation, NS6740 is an effective activator of the cholinergic anti-inflammatory pathway. We observed that the concentration-response relationships for channel activation, both when applied alone and when co-applied with the PAM PNU-120596 are inverted-U shaped with inhibitory/desensitizing activities dominant at high concentrations. We evaluated the potential importance of recently identified binding sites for allosteric activators and tested the hypotheses that the stable desensitization produced by NS6740 may be due to binding to these sites. Our experiments were guided by molecular modeling of NS6740 binding to both the allosteric and orthosteric activation sites on the receptor. Our results indicate that with α7C190A mutants, which have compromised orthosteric activation sites, NS6740 may work at the allosteric activation sites to promote transient PAM-dependent currents but not the stable desensitization seen with wild-type α7 receptors. Modeling NS6740 in the orthosteric binding sites identified S36 as an important residue for NS6740 binding and predicted that an S36V mutation would limit NS6740 activity. The efficacy of NS6740 for α7S36V receptors was reduced to zero, and applications of the compound to α7S36V receptors failed to induce the desensitization observed with wild-type receptors. The results indicate that the unique properties of NS6740 are due primarily to binding at the sites for orthosteric agonists.
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Affiliation(s)
- Maria Chiara Pismataro
- Department of Pharmaceutical Sciences, Medicinal Chemistry Section "Pietro Pratesi", University of Milan, Via L. Mangiagalli 25, 20133, Milan, Italy; Department of Chemistry, University of Florida, P.O. Box 117200, Gainesville, FL, 32611-7200, USA
| | - Nicole A Horenstein
- Department of Chemistry, University of Florida, P.O. Box 117200, Gainesville, FL, 32611-7200, USA
| | - Clare Stokes
- Department of Pharmacology and Therapeutics, University of Florida, P.O. Box 100267, Gainesville, FL, 32610-0267, USA
| | - Clelia Dallanoce
- Department of Pharmaceutical Sciences, Medicinal Chemistry Section "Pietro Pratesi", University of Milan, Via L. Mangiagalli 25, 20133, Milan, Italy.
| | - Ganesh A Thakur
- Department of Pharmaceutical Sciences, School of Pharmacy, Bouvé College of Health Sciences, Northeastern University, Boston, MA, 02115, USA
| | - Roger L Papke
- Department of Pharmacology and Therapeutics, University of Florida, P.O. Box 100267, Gainesville, FL, 32610-0267, USA
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20
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Zheng Q, Wang Y, Zhang S. Beyond Alkaloids: Novel Bioactive Natural Products From Lobelia Species. Front Pharmacol 2021; 12:638210. [PMID: 33762957 PMCID: PMC7982472 DOI: 10.3389/fphar.2021.638210] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2020] [Accepted: 01/25/2021] [Indexed: 01/31/2023] Open
Abstract
In this work, we reviewed the progress in the phytochemical and biological investigations of bioactive components derived from medicinally valuable Lobelia species. In the last 60 years, Lobelia has garnered significant attention from the phytochemist from around the world, majorly due to the discovery of bioactive piperidine alkaloids (e.g., lobinaline and lobeline) in the early 1950s. Later, lobeline underwent clinical trials for several indications including the treatment of attention deficit hyperactivity disorder and a multicenter phase three trial for smoking cessation. Subsequently, several other alkaloids derived from different species of Lobelia were also investigated for their pharmacological characteristics. However, in the last few years, the research focus has started shifting to the characterization of the other novel chemical classes. The major shift has been noticed due to the structurally similar alkaloid components, which essentially share similar pharmacological, physicochemical, and toxicological profiles. In this review, we present an up-to-date overview of their progress with special attention to understanding the molecular mechanisms of the novel bioactive components.
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Affiliation(s)
- Qinfang Zheng
- Hunan Academy of Chinese Medicine, Hunan University of Chinese Medicine, Changsha, China.,Key Laboratory of Dong Medical Research of Hunan Province, Hunan University of Medicine, Huaihua, China
| | - Ye Wang
- Key Laboratory of Dong Medical Research of Hunan Province, Hunan University of Medicine, Huaihua, China
| | - Shuihan Zhang
- Hunan Academy of Chinese Medicine, Hunan University of Chinese Medicine, Changsha, China.,2011 Collaboration and Innovation Center for Digital Chinese Medicine in Hunan, Changsha, China
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21
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FitzGerald EA, Butko MT, Boronat P, Cederfelt D, Abramsson M, Ludviksdottir H, van Muijlwijk-Koezen JE, de Esch IJP, Dobritzsch D, Young T, Danielson UH. Discovery of fragments inducing conformational effects in dynamic proteins using a second-harmonic generation biosensor. RSC Adv 2021; 11:7527-7537. [PMID: 35423271 PMCID: PMC8694943 DOI: 10.1039/d0ra09844b] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Accepted: 01/28/2021] [Indexed: 01/13/2023] Open
Abstract
Biophysical screening of compound libraries for the identification of ligands that interact with a protein is efficient, but does typically not reveal if (or how) ligands may interfere with its functional properties. For this a biochemical/functional assay is required. But for proteins whose function is dependent on a conformational change, such assays are typically complex or have low throughput. Here we have explored a high-throughput second-harmonic generation (SHG) biosensor to detect fragments that induce conformational changes upon binding to a protein in real time and identify dynamic regions. Multiwell plate format SHG assays were developed for wild-type and six engineered single-cysteine mutants of acetyl choline binding protein (AChBP), a homologue to ligand gated ion channels (LGICs). They were conjugated with second harmonic-active labels via amine or maleimide coupling. To validate the assay, it was confirmed that the conformational changes induced in AChBP by nicotinic acetyl choline receptor (nAChR) agonists and antagonists were qualitatively different. A 1056 fragment library was subsequently screened against all variants and conformational modulators of AChBP were successfully identified, with hit rates from 9-22%, depending on the AChBP variant. A subset of four hits was selected for orthogonal validation and structural analysis. A time-resolved grating-coupled interferometry-based biosensor assay confirmed the interaction to be a reversible 1-step 1 : 1 interaction, and provided estimates of affinities and interaction kinetic rate constants (K D = 0.28-63 μM, k a = 0.1-6 μM-1 s-1, k d = 1 s-1). X-ray crystallography of two of the fragments confirmed their binding at a previously described conformationally dynamic site, corresponding to the regulatory site of LGICs. These results reveal that SHG has the sensitivity to identify fragments that induce conformational changes in a protein. A selection of fragment hits with a response profile different to known LGIC regulators was characterized and confirmed to bind to dynamic regions of the protein.
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Affiliation(s)
- Edward A FitzGerald
- Department of Chemistry - BMC, Uppsala University Uppsala 751 23 Sweden
- Beactica Therapeutics Virdings allé 2 Uppsala 754 40 Sweden
| | | | - Pierre Boronat
- Amsterdam Institute of Molecular and Life Sciences (AIMMS), Division of Medicinal Chemistry, Faculty of Science, Vrije Universiteit Amsterdam De Boelelaan 1108 1081 HZ Amsterdam The Netherlands
| | - Daniela Cederfelt
- Department of Chemistry - BMC, Uppsala University Uppsala 751 23 Sweden
| | - Mia Abramsson
- Department of Chemistry - BMC, Uppsala University Uppsala 751 23 Sweden
| | | | - Jacqueline E van Muijlwijk-Koezen
- Amsterdam Institute of Molecular and Life Sciences (AIMMS), Division of Medicinal Chemistry, Faculty of Science, Vrije Universiteit Amsterdam De Boelelaan 1108 1081 HZ Amsterdam The Netherlands
| | - Iwan J P de Esch
- Amsterdam Institute of Molecular and Life Sciences (AIMMS), Division of Medicinal Chemistry, Faculty of Science, Vrije Universiteit Amsterdam De Boelelaan 1108 1081 HZ Amsterdam The Netherlands
| | - Doreen Dobritzsch
- Department of Chemistry - BMC, Uppsala University Uppsala 751 23 Sweden
| | - Tracy Young
- Biodesy, Inc. 170 Harbor Way South San Francisco 94080 CA USA
| | - U Helena Danielson
- Department of Chemistry - BMC, Uppsala University Uppsala 751 23 Sweden
- Science for Life Laboratory, Uppsala University Sweden
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22
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Kulbatskii DS, Shulepko MA, Sluchanko NN, Yablokov EO, Kamyshinsky RA, Chesnokov YM, Kirpichnikov MP, Lyukmanova EN. Efficient screening of ligand-receptor complex formation using fluorescence labeling and size-exclusion chromatography. Biochem Biophys Res Commun 2020; 532:127-133. [PMID: 32828540 DOI: 10.1016/j.bbrc.2020.08.021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Accepted: 08/09/2020] [Indexed: 11/19/2022]
Abstract
Evidence of a complex formation is a crucial step in the structural studies of ligand-receptor interactions. Here we presented a simple and fast approach for qualitative screening of the complex formation between the chimeric extracellular domain of the nicotinic acetylcholine receptor (α7-ECD) and three-finger proteins. Complex formation of snake toxins α-Bgtx and WTX, as well as of recombinant analogs of human proteins Lynx1 and SLURP-1, with α7-ECD was confirmed using fluorescently labeled ligands and size-exclusion chromatography with simultaneous absorbance and fluorescence detection. WTX/α7-ECD complex formation also was confirmed by cryo-EM. The proposed approach could easily be adopted to study the interaction of other receptors with their ligands.
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Affiliation(s)
- D S Kulbatskii
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Miklukho-Maklaya 16/10, Moscow, 117997, Russia
| | - M A Shulepko
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Miklukho-Maklaya 16/10, Moscow, 117997, Russia
| | - N N Sluchanko
- A. N. Bach Institute of Biochemistry, Federal Research Center of Biotechnology of the Russian Academy of Sciences, Leninskiy Prospect 33, Building 1, Moscow, 119071, Russia
| | - E O Yablokov
- Federal State Budgetary Institution "V.N. Orekhovich Research Institute of Biomedical Chemistry", Pogodinskaya 10k8, Moscow, 119121, Russia
| | - R A Kamyshinsky
- National Research Center "Kurchatov Institute", Academic Kurchatov Sq. 1, Moscow, 123182, Russia; Shubnikov Institute of Crystallography of Federal Scientific Research Centre "Crystallography and Photonics" of Russian Academy of Sciences, Leninskiy Prospect 59, Moscow, 119333, Russia
| | - Y M Chesnokov
- National Research Center "Kurchatov Institute", Academic Kurchatov Sq. 1, Moscow, 123182, Russia; Shubnikov Institute of Crystallography of Federal Scientific Research Centre "Crystallography and Photonics" of Russian Academy of Sciences, Leninskiy Prospect 59, Moscow, 119333, Russia
| | - M P Kirpichnikov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Miklukho-Maklaya 16/10, Moscow, 117997, Russia; Biological Faculty, Lomonosov Moscow State University, Leninskie gory, 1k12, Moscow, 119192, Russia
| | - E N Lyukmanova
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Miklukho-Maklaya 16/10, Moscow, 117997, Russia; Biological Faculty, Lomonosov Moscow State University, Leninskie gory, 1k12, Moscow, 119192, Russia.
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23
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Gulsevin A, Meiler J, Horenstein NA. A Computational Analysis of the Factors Governing the Dynamics of α7 nAChR and Its Homologs. Biophys J 2020; 119:1656-1669. [PMID: 33010233 PMCID: PMC7642335 DOI: 10.1016/j.bpj.2020.09.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Revised: 09/10/2020] [Accepted: 09/10/2020] [Indexed: 12/18/2022] Open
Abstract
The α7 nicotinic acetylcholine receptor is a homopentameric ion channel from the Cys-loop receptor superfamily targeted for psychiatric indications and inflammatory pain. Molecular dynamics studies of the receptor have focused on residue mobility and global conformational changes to address receptor function. However, a comparative analysis of α7 with its homologs that cannot trigger channel opening has not been made so far. To identify the residues involved in α7 activation, we ran triplicate 500-ns molecular dynamics simulations with an α7 extracellular domain homology model and two acetylcholine-binding protein homologs. We tested the effect of ligand binding and amino acid sequence on the structure and dynamics of the three proteins. We found that mobile regions identified based on root mean-square deviation and root mean-square fluctuation values are not always consistent among the individual α7 extracellular domain simulations. Comparison of the replica-average properties of the three proteins based on dynamic cross-correlation maps showed that ligand binding affects the coupling between the C-loop and the Cys-loop, vestibular loop, and β1-β2 loops. In addition, the main-immunogenic-region-like domain of α7 went through correlated motions with multiple domains of the receptor. These correlated motions were absent or diminished in α7 homologs, suggesting a unique role in α7 activation.
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Affiliation(s)
- Alican Gulsevin
- Department of Chemistry, Biochemistry Division, University of Florida, Gainesville, Florida; Department of Chemistry, Vanderbilt University, Nashville, Tennessee.
| | - Jens Meiler
- Department of Chemistry, Vanderbilt University, Nashville, Tennessee; Leipzig University Medical School, Institute for Drug Discovery, Leipzig, Germany
| | - Nicole A Horenstein
- Department of Chemistry, Biochemistry Division, University of Florida, Gainesville, Florida
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24
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Paramonov AS, Kocharovskaya MV, Tsarev AV, Kulbatskii DS, Loktyushov EV, Shulepko MA, Kirpichnikov MP, Lyukmanova EN, Shenkarev ZO. Structural Diversity and Dynamics of Human Three-Finger Proteins Acting on Nicotinic Acetylcholine Receptors. Int J Mol Sci 2020; 21:E7280. [PMID: 33019770 PMCID: PMC7582953 DOI: 10.3390/ijms21197280] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Revised: 09/26/2020] [Accepted: 09/28/2020] [Indexed: 12/12/2022] Open
Abstract
Ly-6/uPAR or three-finger proteins (TFPs) contain a disulfide-stabilized β-structural core and three protruding loops (fingers). In mammals, TFPs have been found in epithelium and the nervous, endocrine, reproductive, and immune systems. Here, using heteronuclear NMR, we determined the three-dimensional (3D) structure and backbone dynamics of the epithelial secreted protein SLURP-1 and soluble domains of GPI-anchored TFPs from the brain (Lynx2, Lypd6, Lypd6b) acting on nicotinic acetylcholine receptors (nAChRs). Results were compared with the data about human TFPs Lynx1 and SLURP-2 and snake α-neurotoxins WTX and NTII. Two different topologies of the β-structure were revealed: one large antiparallel β-sheet in Lypd6 and Lypd6b, and two β-sheets in other proteins. α-Helical segments were found in the loops I/III of Lynx2, Lypd6, and Lypd6b. Differences in the surface distribution of charged and hydrophobic groups indicated significant differences in a mode of TFPs/nAChR interactions. TFPs showed significant conformational plasticity: the loops were highly mobile at picosecond-nanosecond timescale, while the β-structural regions demonstrated microsecond-millisecond motions. SLURP-1 had the largest plasticity and characterized by the unordered loops II/III and cis-trans isomerization of the Tyr39-Pro40 bond. In conclusion, plasticity could be an important feature of TFPs adapting their structures for optimal interaction with the different conformational states of nAChRs.
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MESH Headings
- Adaptor Proteins, Signal Transducing/chemistry
- Adaptor Proteins, Signal Transducing/genetics
- Adaptor Proteins, Signal Transducing/metabolism
- Amino Acid Sequence
- Antigens, Ly/chemistry
- Antigens, Ly/genetics
- Antigens, Ly/metabolism
- Binding Sites
- Cloning, Molecular
- Elapid Venoms/chemistry
- Elapid Venoms/metabolism
- Escherichia coli/genetics
- Escherichia coli/metabolism
- GPI-Linked Proteins/chemistry
- GPI-Linked Proteins/genetics
- GPI-Linked Proteins/metabolism
- Gene Expression
- Genetic Vectors/chemistry
- Genetic Vectors/metabolism
- Humans
- Hydrophobic and Hydrophilic Interactions
- Models, Molecular
- Neuropeptides/chemistry
- Neuropeptides/genetics
- Neuropeptides/metabolism
- Nuclear Magnetic Resonance, Biomolecular
- Protein Binding
- Protein Conformation, alpha-Helical
- Protein Conformation, beta-Strand
- Protein Interaction Domains and Motifs
- Protein Isoforms/chemistry
- Protein Isoforms/genetics
- Protein Isoforms/metabolism
- Receptors, Nicotinic/chemistry
- Receptors, Nicotinic/genetics
- Receptors, Nicotinic/metabolism
- Recombinant Proteins/chemistry
- Recombinant Proteins/genetics
- Recombinant Proteins/metabolism
- Sequence Alignment
- Sequence Homology, Amino Acid
- Urokinase-Type Plasminogen Activator/chemistry
- Urokinase-Type Plasminogen Activator/genetics
- Urokinase-Type Plasminogen Activator/metabolism
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Affiliation(s)
- Alexander S. Paramonov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 119997 Moscow, Russia; (A.S.P.); (M.V.K.); (A.V.T.); (D.S.K.); (E.V.L.); (M.A.S.); (M.P.K.)
| | - Milita V. Kocharovskaya
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 119997 Moscow, Russia; (A.S.P.); (M.V.K.); (A.V.T.); (D.S.K.); (E.V.L.); (M.A.S.); (M.P.K.)
- Phystech School of Biological and Medical Physics, Moscow Institute of Physics and Technology (National Research University), 141701 Dolgoprudny, Moscow Region, Russia
| | - Andrey V. Tsarev
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 119997 Moscow, Russia; (A.S.P.); (M.V.K.); (A.V.T.); (D.S.K.); (E.V.L.); (M.A.S.); (M.P.K.)
- Phystech School of Biological and Medical Physics, Moscow Institute of Physics and Technology (National Research University), 141701 Dolgoprudny, Moscow Region, Russia
| | - Dmitrii S. Kulbatskii
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 119997 Moscow, Russia; (A.S.P.); (M.V.K.); (A.V.T.); (D.S.K.); (E.V.L.); (M.A.S.); (M.P.K.)
| | - Eugene V. Loktyushov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 119997 Moscow, Russia; (A.S.P.); (M.V.K.); (A.V.T.); (D.S.K.); (E.V.L.); (M.A.S.); (M.P.K.)
| | - Mikhail A. Shulepko
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 119997 Moscow, Russia; (A.S.P.); (M.V.K.); (A.V.T.); (D.S.K.); (E.V.L.); (M.A.S.); (M.P.K.)
| | - Mikhail P. Kirpichnikov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 119997 Moscow, Russia; (A.S.P.); (M.V.K.); (A.V.T.); (D.S.K.); (E.V.L.); (M.A.S.); (M.P.K.)
- Faculty of Biology, Lomonosov Moscow State University, 119234 Moscow, Russia
| | - Ekaterina N. Lyukmanova
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 119997 Moscow, Russia; (A.S.P.); (M.V.K.); (A.V.T.); (D.S.K.); (E.V.L.); (M.A.S.); (M.P.K.)
- Phystech School of Biological and Medical Physics, Moscow Institute of Physics and Technology (National Research University), 141701 Dolgoprudny, Moscow Region, Russia
| | - Zakhar O. Shenkarev
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 119997 Moscow, Russia; (A.S.P.); (M.V.K.); (A.V.T.); (D.S.K.); (E.V.L.); (M.A.S.); (M.P.K.)
- Phystech School of Biological and Medical Physics, Moscow Institute of Physics and Technology (National Research University), 141701 Dolgoprudny, Moscow Region, Russia
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25
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Tetrapeptide Ac-HAEE-NH 2 Protects α4β2 nAChR from Inhibition by Aβ. Int J Mol Sci 2020; 21:ijms21176272. [PMID: 32872553 PMCID: PMC7504039 DOI: 10.3390/ijms21176272] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Revised: 08/25/2020] [Accepted: 08/27/2020] [Indexed: 12/25/2022] Open
Abstract
The cholinergic deficit in Alzheimer’s disease (AD) may arise from selective loss of cholinergic neurons caused by the binding of Aβ peptide to nicotinic acetylcholine receptors (nAChRs). Thus, compounds preventing such an interaction are needed to address the cholinergic dysfunction. Recent findings suggest that the 11EVHH14 site in Aβ peptide mediates its interaction with α4β2 nAChR. This site contains several charged amino acid residues, hence we hypothesized that the formation of Aβ-α4β2 nAChR complex is based on the interaction of 11EVHH14 with its charge-complementary counterpart in α4β2 nAChR. Indeed, we discovered a 35HAEE38 site in α4β2 nAChR, which is charge-complementary to 11EVHH14, and molecular modeling showed that a stable Aβ42-α4β2 nAChR complex could be formed via the 11EVHH14:35HAEE38 interface. Using surface plasmon resonance and bioinformatics approaches, we further showed that a corresponding tetrapeptide Ac-HAEE-NH2 can bind to Aβ via 11EVHH14 site. Finally, using two-electrode voltage clamp in Xenopus laevis oocytes, we showed that Ac-HAEE-NH2 tetrapeptide completely abolishes the Aβ42-induced inhibition of α4β2 nAChR. Thus, we suggest that 35HAEE38 is a potential binding site for Aβ on α4β2 nAChR and Ac-HAEE-NH2 tetrapeptide corresponding to this site is a potential therapeutic for the treatment of α4β2 nAChR-dependent cholinergic dysfunction in AD.
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26
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Arunrungvichian K, Chongruchiroj S, Sarasamkan J, Schüürmann G, Brust P, Vajragupta O. In Silico Finding of Key Interaction Mediated α3β4 and α7 Nicotinic Acetylcholine Receptor Ligand Selectivity of Quinuclidine-Triazole Chemotype. Int J Mol Sci 2020; 21:E6189. [PMID: 32867140 PMCID: PMC7504379 DOI: 10.3390/ijms21176189] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Revised: 08/20/2020] [Accepted: 08/25/2020] [Indexed: 12/12/2022] Open
Abstract
The selective binding of six (S)-quinuclidine-triazoles and their (R)-enantiomers to nicotinic acetylcholine receptor (nAChR) subtypes α3β4 and α7, respectively, were analyzed by in silico docking to provide the insight into the molecular basis for the observed stereospecific subtype discrimination. Homology modeling followed by molecular docking and molecular dynamics (MD) simulations revealed that unique amino acid residues in the complementary subunits of the nAChR subtypes are involved in subtype-specific selectivity profiles. In the complementary β4-subunit of the α3β4 nAChR binding pocket, non-conserved AspB173 through a salt bridge was found to be the key determinant for the α3β4 selectivity of the quinuclidine-triazole chemotype, explaining the 47-327-fold affinity of the (S)-enantiomers as compared to their (R)-enantiomer counterparts. Regarding the α7 nAChR subtype, the amino acids promoting a however significantly lower preference for the (R)-enantiomers were the conserved TyrA93, TrpA149 and TrpB55 residues. The non-conserved amino acid residue in the complementary subunit of nAChR subtypes appeared to play a significant role for the nAChR subtype-selective binding, particularly at the heteropentameric subtype, whereas the conserved amino acid residues in both principal and complementary subunits are essential for ligand potency and efficacy.
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Affiliation(s)
- Kuntarat Arunrungvichian
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Mahidol University, 447 Sri-Ayutthaya Road, Bangkok 10400, Thailand;
| | - Sumet Chongruchiroj
- Department of Microbiology, Faculty of Pharmacy, Mahidol University, 447 Sri-Ayutthaya Road, Bangkok 10400, Thailand;
| | - Jiradanai Sarasamkan
- Division of Nuclear Medicine, Department of Radiology, Faculty of Medicine, Khon Kaen University, 123 Mittraparp Highway, Khon Kaen 4002, Thailand;
| | - Gerrit Schüürmann
- UFZ Department of Ecological Chemistry, Helmholtz Centre for Environmental Research, Permoserstrasse 15, 04318 Leipzig, Germany;
- Institute of Organic Chemistry, Technical University Bergakademie Freiberg, Leipziger Strasse 29, 09596 Freiberg, Germany
| | - Peter Brust
- Department of Neuroradiopharmaceuticals, Institute of Radiopharmaceutical Cancer Research, Helmholtz-Zentrum Dresden-Rossendorf, Permoserstrasse 15, 04318 Leipzig, Germany;
| | - Opa Vajragupta
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Mahidol University, 447 Sri-Ayutthaya Road, Bangkok 10400, Thailand;
- Office of Research Affairs, Faculty of Pharmaceutical Sciences, Chulalongkorn University, 254 Phayathai Road, Bangkok 10330, Thailand
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27
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Gulsevin A. Nicotinic receptor pharmacology in silico: Insights and challenges. Neuropharmacology 2020; 177:108257. [PMID: 32738311 DOI: 10.1016/j.neuropharm.2020.108257] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Revised: 07/16/2020] [Accepted: 07/26/2020] [Indexed: 02/07/2023]
Abstract
Nicotinic acetylcholine receptors (nAChR) are homo- or hetero-pentameric ligand-gated ion channels of the Cys-loop superfamily and play important roles in the nervous system and muscles. Studies on nAChR benefit from in silico modeling due to the lack of high-resolution structures for most receptor subtypes and challenges in experiments addressing the complex mechanism of activation involving allosteric sites. Although there is myriad of computational modeling studies on nAChR, the multitude of the methods and parameters used in these studies makes modeling nAChR a daunting task, particularly for the non-experts in the field. To address this problem, the modeling literature on Torpedo nAChR and α7 nAChR were focused on as examples of heteromeric and homomeric nAChR, and the key in silico modeling studies between the years 1995-2019 were concisely reviewed. This was followed by a critical analysis of these studies by comparing the findings with each other and with the emerging experimental and computational data on nAChR. Based on these critical analyses, suggestions were made to guide the future researchers in the field of in silico modeling of nAChR. This article is part of the special issue on 'Contemporary Advances in Nicotine Neuropharmacology'.
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Affiliation(s)
- Alican Gulsevin
- Department of Chemistry, Vanderbilt University, Nashville, TN, USA, 37221.
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28
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Ganeshpurkar A, Singh R, Kumar D, Divya, Shivhare S, Kumar A, Singh SK. Computational binding study with α7 nicotinic acetylcholine receptor of Anvylic-3288: an allosteric modulator. MOLECULAR SIMULATION 2020. [DOI: 10.1080/08927022.2020.1795166] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Affiliation(s)
- Ankit Ganeshpurkar
- Pharmaceutical Chemistry Research Laboratory, Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi, India
| | - Ravi Singh
- Pharmaceutical Chemistry Research Laboratory, Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi, India
| | - Devendra Kumar
- Pharmaceutical Chemistry Research Laboratory, Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi, India
| | - Divya
- Pharmaceutical Chemistry Research Laboratory, Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi, India
| | - Shalini Shivhare
- Pharmaceutical Chemistry Research Laboratory, Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi, India
| | - Ashok Kumar
- Pharmaceutical Chemistry Research Laboratory, Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi, India
| | - Sushil Kumar Singh
- Pharmaceutical Chemistry Research Laboratory, Department of Pharmaceutical Engineering & Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi, India
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29
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Rauschenberger V, von Wardenburg N, Schaefer N, Ogino K, Hirata H, Lillesaar C, Kluck CJ, Meinck H, Borrmann M, Weishaupt A, Doppler K, Wickel J, Geis C, Sommer C, Villmann C. Glycine Receptor
Autoantibodies Impair Receptor Function and Induce Motor Dysfunction. Ann Neurol 2020; 88:544-561. [DOI: 10.1002/ana.25832] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2019] [Revised: 06/23/2020] [Accepted: 06/23/2020] [Indexed: 12/22/2022]
Affiliation(s)
- Vera Rauschenberger
- Institute for Clinical NeurobiologyUniversity Hospital, Julius Maximilian University of Würzburg Würzburg Germany
| | - Niels von Wardenburg
- Institute for Clinical NeurobiologyUniversity Hospital, Julius Maximilian University of Würzburg Würzburg Germany
| | - Natascha Schaefer
- Institute for Clinical NeurobiologyUniversity Hospital, Julius Maximilian University of Würzburg Würzburg Germany
| | - Kazutoyo Ogino
- Department of Chemistry and Biological ScienceCollege of Science and Engineering, Aoyama Gakuin University Tokyo Japan
| | - Hiromi Hirata
- Department of Chemistry and Biological ScienceCollege of Science and Engineering, Aoyama Gakuin University Tokyo Japan
| | - Christina Lillesaar
- Department of Child and Adolescent PsychiatryCenter of Mental Health, University Hospital of Würzburg Würzburg Germany
| | - Christoph J. Kluck
- Institute of Biochemistry, Emil Fischer Center, Friedrich Alexander University Erlangen–Nürnberg Erlangen Germany
| | | | - Marc Borrmann
- WittenHelios University Hospital Wuppertal, Department of Nephrology and Rheumatology, Witten/Herdecke University Germany
| | - Andreas Weishaupt
- Department of NeurologyUniversity Hospital Würzburg Würzburg Germany
| | - Kathrin Doppler
- Department of NeurologyUniversity Hospital Würzburg Würzburg Germany
| | - Jonathan Wickel
- Section of Translational Neuroimmunology, Department of NeurologyJena University Hospital Jena Germany
| | - Christian Geis
- Section of Translational Neuroimmunology, Department of NeurologyJena University Hospital Jena Germany
| | - Claudia Sommer
- Department of NeurologyUniversity Hospital Würzburg Würzburg Germany
| | - Carmen Villmann
- Institute for Clinical NeurobiologyUniversity Hospital, Julius Maximilian University of Würzburg Würzburg Germany
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30
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Papke RL, Garai S, Stokes C, Horenstein NA, Zimmerman AD, Abboud KA, Thakur GA. Differing Activity Profiles of the Stereoisomers of 2,3,5,6TMP-TQS, a Putative Silent Allosteric Modulator of α7 nAChR. Mol Pharmacol 2020; 98:292-302. [PMID: 32690627 DOI: 10.1124/mol.120.119958] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Accepted: 07/13/2020] [Indexed: 12/20/2022] Open
Abstract
Many synthetic compounds to which we attribute specific activities are produced as racemic mixtures of stereoisomers, and it may be that all the desired activity comes from a single enantiomer. We have previously shown this to be the case with the α7 nicotinic acetylcholine receptor positive allosteric modulator (PAM) 3a,4,5,9b-Tetrahydro-4-(1-naphthalenyl)-3H-cyclopentan[c]quinoline-8-sulfonamide (TQS) and the α7 ago-PAM 4BP-TQS. Cis-trans-4-(2,3,5,6-tetramethylphenyl)-3a,4,5,9b-te-trahydro-3H-cyclopenta[c]quinoline-8-sulfonamide (2,3,5,6TMP-TQS), previously published as a "silent allosteric modulator" and an antagonist of α7 allosteric activation, shares the same scaffold with three chiral centers as the aforementioned compounds. We isolated the enantiomers of 2,3,5,6TMP-TQS and determined that the (-) isomer was a significantly better antagonist than the (+) isomer of the allosteric activation of both wild-type α7 and the nonorthosterically activatible C190A α7 mutant by the ago-PAM GAT107 (the active isomer of 4BP-TQS). In contrast, (+)2,3,5,6TMP-TQS proved to be an α7 PAM. (-)2,3,5,6TMP-TQS was shown to antagonize the allosteric activation of α7 by the structurally unrelated ago-PAM B-973B as well as the allosteric activation of the TQS-sensitive α4β2L15'M mutant. In silico docking of 2,3,5,6TMP-TQS in the putative allosteric activation binding site suggested a specific interaction of the (-) enantiomer with α7T106, and allosteric activation of α7T106 mutants was not inhibited by (-)2,3,5,6TMP-TQS, confirming the importance of this interaction and supporting the model of the allosteric binding site. Comparisons and contrasts between 2,3,5,6TMP-TQS isomers and active and inactive enantiomers of other TQS-related compounds identify the orientation of the cyclopentenyl ring to the plane of the core quinoline to be a crucial determinate of PAM activity. SIGNIFICANCE STATEMENT: Many synthetic ligands are in use as racemic preparations. We show that one enantiomer of the TQS analog Cis-trans-4-(2,3,5,6-tetramethylphenyl)-3a,4,5,9b-te-trahydro-3H-cyclopenta[c]quinoline-8-sulfonamide, originally reported to lack activity when used as a racemic preparation, is an α7 nicotinic acetylcholine receptor positive allosteric modulator (PAM). The other enantiomer is not a PAM, but it is an effective allosteric antagonist. In silico studies and structural comparisons identify essential elements of both the allosteric ligands and receptor binding sites important for these allosteric activities.
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Affiliation(s)
- Roger L Papke
- Departments of Pharmacology and Therapeutics (R.L.P., C.S., A.D.Z.) and Chemistry (N.A.H., K.A.A.), University of Florida, Gainesville, Florida; and Department of Pharmaceutical Sciences, School of Pharmacy, Bouvé College of Health Sciences, Northeastern University, Boston, Massachusetts (S.G., G.A.T.)
| | - Sumanta Garai
- Departments of Pharmacology and Therapeutics (R.L.P., C.S., A.D.Z.) and Chemistry (N.A.H., K.A.A.), University of Florida, Gainesville, Florida; and Department of Pharmaceutical Sciences, School of Pharmacy, Bouvé College of Health Sciences, Northeastern University, Boston, Massachusetts (S.G., G.A.T.)
| | - Clare Stokes
- Departments of Pharmacology and Therapeutics (R.L.P., C.S., A.D.Z.) and Chemistry (N.A.H., K.A.A.), University of Florida, Gainesville, Florida; and Department of Pharmaceutical Sciences, School of Pharmacy, Bouvé College of Health Sciences, Northeastern University, Boston, Massachusetts (S.G., G.A.T.)
| | - Nicole A Horenstein
- Departments of Pharmacology and Therapeutics (R.L.P., C.S., A.D.Z.) and Chemistry (N.A.H., K.A.A.), University of Florida, Gainesville, Florida; and Department of Pharmaceutical Sciences, School of Pharmacy, Bouvé College of Health Sciences, Northeastern University, Boston, Massachusetts (S.G., G.A.T.)
| | - Arthur D Zimmerman
- Departments of Pharmacology and Therapeutics (R.L.P., C.S., A.D.Z.) and Chemistry (N.A.H., K.A.A.), University of Florida, Gainesville, Florida; and Department of Pharmaceutical Sciences, School of Pharmacy, Bouvé College of Health Sciences, Northeastern University, Boston, Massachusetts (S.G., G.A.T.)
| | - Khalil A Abboud
- Departments of Pharmacology and Therapeutics (R.L.P., C.S., A.D.Z.) and Chemistry (N.A.H., K.A.A.), University of Florida, Gainesville, Florida; and Department of Pharmaceutical Sciences, School of Pharmacy, Bouvé College of Health Sciences, Northeastern University, Boston, Massachusetts (S.G., G.A.T.)
| | - Ganesh A Thakur
- Departments of Pharmacology and Therapeutics (R.L.P., C.S., A.D.Z.) and Chemistry (N.A.H., K.A.A.), University of Florida, Gainesville, Florida; and Department of Pharmaceutical Sciences, School of Pharmacy, Bouvé College of Health Sciences, Northeastern University, Boston, Massachusetts (S.G., G.A.T.)
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Papke RL, Lindstrom JM. Nicotinic acetylcholine receptors: Conventional and unconventional ligands and signaling. Neuropharmacology 2020; 168:108021. [PMID: 32146229 PMCID: PMC7610230 DOI: 10.1016/j.neuropharm.2020.108021] [Citation(s) in RCA: 65] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2019] [Revised: 02/05/2020] [Accepted: 02/25/2020] [Indexed: 12/28/2022]
Abstract
Postsynaptic nAChRs in the peripheral nervous system are critical for neuromuscular and autonomic neurotransmission. Pre- and peri-synaptic nAChRs in the brain modulate neurotransmission and are responsible for the addictive effects of nicotine. Subtypes of nAChRs in lymphocytes and non-synaptic locations may modulate inflammation and other cellular functions. All AChRs that function as ligand-gated ion channels are formed from five homologous subunits organized to form a central cation channel whose opening is regulated by ACh bound at extracellular subunit interfaces. nAChR subtype subunit composition can range from α7 homomers to α4β2α6β2β3 heteromers. Subtypes differ in affinities for ACh and other agonists like nicotine and in efficiencies with which their channels are opened and desensitized. Subtypes also differ in affinities for antagonists and for positive and negative allosteric modulators. Some agonists are "silent" with respect to channel opening, and AChRs may be able to signal metabotropic pathways by releasing G-proteins independent of channel opening. Electrophysiological studies that can resolve single-channel openings and molecular genetic approaches have allowed characterization of the structures of ligand binding sites, the cation channel, and the linkages between them, as well as the organization of AChR subunits and their contributions to function. Crystallography and cryo-electron-microscopy are providing increasing insights into the structures and functions of AChRs. However, much remains to be learned about both AChR structure and function, the in vivo functional roles of some AChR subtypes, and the development of better pharmacological tools directed at AChRs to treat addiction, pain, inflammation, and other medically important issues. This article is part of the special issue on 'Contemporary Advances in Nicotine Neuropharmacology'.
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Affiliation(s)
- Roger L Papke
- Department of Pharmacology and Therapeutics, University of Florida, P.O. Box 100267, Gainesville, FL, 32610-0267, USA.
| | - Jon M Lindstrom
- Department of Neuroscience, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA
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32
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Brams M, Govaerts C, Kambara K, Price KL, Spurny R, Gharpure A, Pardon E, Evans GL, Bertrand D, Lummis SCR, Hibbs RE, Steyaert J, Ulens C. Modulation of the Erwinia ligand-gated ion channel (ELIC) and the 5-HT 3 receptor via a common vestibule site. eLife 2020; 9:e51511. [PMID: 31990273 PMCID: PMC7015668 DOI: 10.7554/elife.51511] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2019] [Accepted: 01/27/2020] [Indexed: 01/13/2023] Open
Abstract
Pentameric ligand-gated ion channels (pLGICs) or Cys-loop receptors are involved in fast synaptic signaling in the nervous system. Allosteric modulators bind to sites that are remote from the neurotransmitter binding site, but modify coupling of ligand binding to channel opening. In this study, we developed nanobodies (single domain antibodies), which are functionally active as allosteric modulators, and solved co-crystal structures of the prokaryote (Erwinia) channel ELIC bound either to a positive or a negative allosteric modulator. The allosteric nanobody binding sites partially overlap with those of small molecule modulators, including a vestibule binding site that is not accessible in some pLGICs. Using mutagenesis, we extrapolate the functional importance of the vestibule binding site to the human 5-HT3 receptor, suggesting a common mechanism of modulation in this protein and ELIC. Thus we identify key elements of allosteric binding sites, and extend drug design possibilities in pLGICs with an accessible vestibule site.
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Affiliation(s)
- Marijke Brams
- Laboratory of Structural Neurobiology, Department of Cellular and Molecular Medicine, Faculty of Medicine, KU LeuvenLeuvenBelgium
| | - Cedric Govaerts
- Laboratory for the Structure and Function of Biological Membranes, Center for Structural Biology and Bioinformatics, Université libre de BruxellesBrusselsBelgium
| | | | - Kerry L Price
- Department of Biochemistry, University of CambridgeCambridgeUnited Kingdom
| | - Radovan Spurny
- Laboratory of Structural Neurobiology, Department of Cellular and Molecular Medicine, Faculty of Medicine, KU LeuvenLeuvenBelgium
| | - Anant Gharpure
- Department of Neuroscience, University of Texas Southwestern Medical CenterDallasUnited States
- Department of Biophysics, University of Texas Southwestern Medical CenterDallasUnited States
| | - Els Pardon
- Structural Biology Brussels, Vrije Universiteit BrusselBrusselsBelgium
- VIB-VUB Center for Structural Biology, VIBBrusselsBelgium
| | - Genevieve L Evans
- Laboratory of Structural Neurobiology, Department of Cellular and Molecular Medicine, Faculty of Medicine, KU LeuvenLeuvenBelgium
| | | | - Sarah CR Lummis
- Department of Biochemistry, University of CambridgeCambridgeUnited Kingdom
| | - Ryan E Hibbs
- Department of Neuroscience, University of Texas Southwestern Medical CenterDallasUnited States
- Department of Biophysics, University of Texas Southwestern Medical CenterDallasUnited States
| | - Jan Steyaert
- Structural Biology Brussels, Vrije Universiteit BrusselBrusselsBelgium
- VIB-VUB Center for Structural Biology, VIBBrusselsBelgium
| | - Chris Ulens
- Laboratory of Structural Neurobiology, Department of Cellular and Molecular Medicine, Faculty of Medicine, KU LeuvenLeuvenBelgium
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33
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Fráguas RM, Costa VA, Terra WC, Aguiar AP, Martins SJ, Campos VP, Oliveira DF. Toxicities of 4,5-Dihydroisoxazoles Against Root-Knot Nematodes and in Silico Studies of Their Modes of Action. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2020; 68:523-529. [PMID: 31908169 DOI: 10.1021/acs.jafc.9b07839] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The present work sought to contribute to the development of new nematicides. Benzaldehydes were initially converted to nitrile oxides that underwent 1,3-dipolar cycloaddition reactions with methyl acrylate to generate 4,5-dihydroisoxazoles. In in vitro tests, methyl 3-phenyl-4,5-dihydroisoxazole-5-carboxylate (1) and methyl 3-(4-chlorophenyl)-4,5-dihydroisoxazole-5-carboxylate (4) increased the mortality of Meloidogyne exigua and Meloidogyne incognita second-stage juveniles (J2). Compounds 1 and 4 presented necessary concentrations of 398 and 501 μg mL-1, respectively, to kill 50% of M. incognita J2 (LC50 values), while the value for carbofuran (positive control) was 168 μg mL-1. In in vivo tests, compounds 1 and 4 reduced the number of M. incognita galls in tomato roots by 70 and 40%, respectively, and the number of eggs by 89 and 44%. Using an in silico approach, we showed that compounds 1 and 4 were toxic to the nematodes by binding to the allosteric binding sites of the agonist-binding domains of the nematode nicotinic acetylcholine receptors. These results opened up possibilities for further investigations aimed at developing novel commercial nematicides.
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Affiliation(s)
- Rodrigo M Fráguas
- Laboratory of Organic Synthesis, Department of Chemistry , Instituto Militar de Engenharia , Rio de Janeiro CEP 22290-270 , Brazil
| | | | | | - Alcino P Aguiar
- Laboratory of Organic Synthesis, Department of Chemistry , Instituto Militar de Engenharia , Rio de Janeiro CEP 22290-270 , Brazil
| | - Samuel J Martins
- Department of Plant Pathology and Environmental Microbiology , Pennsylvania State University , University Park , State College , Pennsylvania 16802 , United States
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34
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Gulsevin A, Papke RL, Horenstein N. In Silico Modeling of the α7 Nicotinic Acetylcholine Receptor: New Pharmacological Challenges Associated with Multiple Modes of Signaling. Mini Rev Med Chem 2020; 20:841-864. [PMID: 32000651 PMCID: PMC8719523 DOI: 10.2174/1389557520666200130105256] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2019] [Revised: 11/06/2019] [Accepted: 11/07/2019] [Indexed: 12/13/2022]
Abstract
The α7 nicotinic acetylcholine receptor is a homopentameric ion-channel of the Cys-loop superfamily characterized by its low probability of opening, high calcium permeability, and rapid desensitization. The α7 receptor has been targeted for the treatment of the cognitive symptoms of schizophrenia, depression, and Alzheimer's disease, but it is also involved in inflammatory modulation as a part of the cholinergic anti-inflammatory pathway. Despite its functional importance, in silico studies of the α7 receptor cannot produce a general model explaining the structural features of receptor activation, nor predict the mode of action for various ligand classes. Two particular problems in modeling the α7 nAChR are the absence of a high-resolution structure and the presence of five potentially nonequivalent orthosteric ligand binding sites. There is wide variability regarding the templates used for homology modeling, types of ligands investigated, simulation methods, and simulation times. However, a systematic survey focusing on the methodological similarities and differences in modeling α7 has not been done. In this work, we make a critical analysis of the modeling literature of α7 nAChR by comparing the findings of computational studies with each other and with experimental studies under the main topics of structural studies, ligand binding studies, and comparisons with other nAChR. In light of our findings, we also summarize current problems in the field and make suggestions for future studies concerning modeling of the α7 receptor.
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Affiliation(s)
- Alican Gulsevin
- Department of Chemistry, University of Florida, P.O. Box 117200, Gainesville, FL, 32611-7200, United States
| | - Roger L Papke
- Department of Pharmacology and Therapeutics, University of Florida, P.O. Box 100267, Gainesville, FL 32610, United States
| | - Nicole Horenstein
- Department of Chemistry, University of Florida, P.O. Box 117200, Gainesville, FL, 32611-7200, United States
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35
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Albulescu LO, Kazandjian T, Slagboom J, Bruyneel B, Ainsworth S, Alsolaiss J, Wagstaff SC, Whiteley G, Harrison RA, Ulens C, Kool J, Casewell NR. A Decoy-Receptor Approach Using Nicotinic Acetylcholine Receptor Mimics Reveals Their Potential as Novel Therapeutics Against Neurotoxic Snakebite. Front Pharmacol 2019; 10:848. [PMID: 31417406 PMCID: PMC6683245 DOI: 10.3389/fphar.2019.00848] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2019] [Accepted: 07/02/2019] [Indexed: 12/24/2022] Open
Abstract
Snakebite is a neglected tropical disease that causes 138,000 deaths each year. Neurotoxic snake venoms contain small neurotoxins, including three-finger toxins (3FTxs), which can cause rapid paralysis in snakebite victims by blocking postsynaptic transmission via nicotinic acetylcholine receptors (nAChRs). These toxins are typically weakly immunogenic and thus are often not effectively targeted by current polyclonal antivenom therapies. We investigated whether nAChR mimics, also known as acetylcholine binding proteins (AChBPs), could effectively capture 3FTxs and therefore be developed as a novel class of snake-generic therapeutics for combatting neurotoxic envenoming. First, we identified the binding specificities of 3FTx from various medically important elapid snake venoms to nAChR using two recombinant nAChR mimics: the AChBP from Lymnaea stagnalis and a humanized neuronal α7 version (α7-AChBP). We next characterized these AChBP-bound and unbound fractions using SDS-PAGE and mass spectrometry. Interestingly, both mimics effectively captured long-chain 3FTxs from multiple snake species but largely failed to capture the highly related short-chain 3FTxs, suggesting a high level of binding specificity. We next investigated whether nAChR mimics could be used as snakebite therapeutics. We showed that while α7-AChBP alone did not protect against Naja haje (Egyptian cobra) venom lethality in vivo, it significantly prolonged survival times when coadministered with a nonprotective dose of antivenom. Thus, nAChR mimics are capable of neutralizing specific venom toxins and may be useful adjunct therapeutics for improving the safety and affordability of existing snakebite treatments by reducing therapeutic doses. Our findings justify exploring the future development of AChBPs as potential snakebite treatments.
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Affiliation(s)
- Laura-Oana Albulescu
- Centre for Snakebite Research & Interventions, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Taline Kazandjian
- Centre for Snakebite Research & Interventions, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Julien Slagboom
- AIMMS Division of BioMolecular Analysis, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
| | - Ben Bruyneel
- AIMMS Division of BioMolecular Analysis, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
| | - Stuart Ainsworth
- Centre for Snakebite Research & Interventions, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Jaffer Alsolaiss
- Centre for Snakebite Research & Interventions, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Simon C Wagstaff
- Bioinformatics Unit, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Gareth Whiteley
- Centre for Snakebite Research & Interventions, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Robert A Harrison
- Centre for Snakebite Research & Interventions, Liverpool School of Tropical Medicine, Liverpool, United Kingdom.,Centre for Drugs and Diagnostics, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Chris Ulens
- Laboratory of Structural Neurobiology, Department of Cellular and Molecular Medicine, Faculty of Medicine, KU Leuven, Leuven, Belgium
| | - Jeroen Kool
- AIMMS Division of BioMolecular Analysis, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
| | - Nicholas R Casewell
- Centre for Snakebite Research & Interventions, Liverpool School of Tropical Medicine, Liverpool, United Kingdom.,Centre for Drugs and Diagnostics, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
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36
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Isomerization of Asp7 in Beta-Amyloid Enhances Inhibition of the α7 Nicotinic Receptor and Promotes Neurotoxicity. Cells 2019; 8:cells8080771. [PMID: 31349637 PMCID: PMC6721525 DOI: 10.3390/cells8080771] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Revised: 07/19/2019] [Accepted: 07/23/2019] [Indexed: 01/02/2023] Open
Abstract
Cholinergic dysfunction in Alzheimer’s disease (AD) can be mediated by the neuronal α7 nicotinic acetylcholine receptor (α7nAChR). Beta-amyloid peptide (Aβ) binds to the α7nAChR, disrupting the receptor’s function and causing neurotoxicity. In vivo not only Aβ but also its modified forms can drive AD pathogenesis. One of these forms, iso-Aβ (containing an isomerized Asp7 residue), shows an increased neurotoxicity in vitro and stimulates amyloidogenesis in vivo. We suggested that such effects of iso-Aβ are α7nAChR-dependent. Here, using calcium imaging and electrophysiology, we found that iso-Aβ is a more potent inhibitor of the α7nAChR-mediated calcium current than unmodified Aβ. However, Asp7 isomerization eliminated the ability of Aβ to decrease the α7nAChR levels. These data indicate differences in the interaction of the peptides with the α7nAChR, which we demonstrated using computer modeling. Neither Aβ nor iso-Aβ competed with 125I-α-bungarotoxin for binding to the orthosteric site of the receptor, suggesting the allosteric binging mode of the peptides. Further we found that increased neurotoxicity of iso-Aβ was mediated by the α7nAChR. Thus, the isomerization of Asp7 enhances the inhibitory effect of Aβ on the functional activity of the α7nAChR, which may be an important factor in the disruption of the cholinergic system in AD.
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37
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Cecon E, Dam J, Luka M, Gautier C, Chollet AM, Delagrange P, Danober L, Jockers R. Quantitative assessment of oligomeric amyloid β peptide binding to α7 nicotinic receptor. Br J Pharmacol 2019; 176:3475-3488. [PMID: 30981214 DOI: 10.1111/bph.14688] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Revised: 03/14/2019] [Accepted: 03/19/2019] [Indexed: 01/26/2023] Open
Abstract
BACKGROUND AND PURPOSE Progressive dysfunction of cholinergic transmission is a well-known characteristic of Alzheimer's disease (AD). Amyloid β (Aβ) peptide oligomers are known to play a central role in AD and are suggested to impair the function of the cholinergic nicotinic ACh receptor α7 (α7nAChR). However, the mechanism underlying the effect of Aβ on α7nAChR function is not fully understood, limiting the therapeutic exploration of this observation in AD. Here, we aimed to detect and characterize Aβ binding to α7nAChR, including the possibility of interfering with this interaction for therapeutic purposes. EXPERIMENTAL APPROACH We developed a specific and quantitative time-resolved FRET (TR-FRET)-based binding assay for Aβ to α7nAChR and pharmacologically characterized this interaction. KEY RESULTS We demonstrated specific and high-affinity (low nanomolar) binding of Aβ to the orthosteric binding site of α7nAChR. Aβ binding was prevented and reversed by the well-characterized orthosteric ligands of α7nAChR (epibatidine, α-bungarotoxin, methylylcaconitine, PNU-282987, S24795, and EVP6124) and by the type II positive allosteric modulator (PAM) PNU-120596 but not by the type I PAM NS1738. CONCLUSIONS AND IMPLICATIONS Our TR-FRET Aβ binding assay demonstrates for the first time the specific binding of Aβ to α7nAChR, which will be a crucial tool for the development, testing, and selection of a novel generation of AD drug candidates targeting Aβ/α7nAChR complexes with high specificity and fewer side effects compared to currently approved α7nAChR drugs. LINKED ARTICLES This article is part of a themed section on Therapeutics for Dementia and Alzheimer's Disease: New Directions for Precision Medicine. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v176.18/issuetoc.
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Affiliation(s)
- Erika Cecon
- Inserm U1016, Institut Cochin, Dept Endocrinology, Metabolism and Diabetes, Paris, France.,CNRS UMR 8104, Paris, France.,University Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Julie Dam
- Inserm U1016, Institut Cochin, Dept Endocrinology, Metabolism and Diabetes, Paris, France.,CNRS UMR 8104, Paris, France.,University Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Marine Luka
- Inserm U1016, Institut Cochin, Dept Endocrinology, Metabolism and Diabetes, Paris, France.,CNRS UMR 8104, Paris, France.,University Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Clément Gautier
- Institut de Recherches SERVIER, Division Therapeutic Innovation in Neuropsychiatry, Croissy-sur-Seine, France
| | - Anne-Marie Chollet
- Institut de Recherches SERVIER, Division Therapeutic Innovation in Neuropsychiatry, Croissy-sur-Seine, France
| | - Philippe Delagrange
- Institut de Recherches SERVIER, Division Therapeutic Innovation in Neuropsychiatry, Croissy-sur-Seine, France
| | - Laurence Danober
- Institut de Recherches SERVIER, Division Therapeutic Innovation in Neuropsychiatry, Croissy-sur-Seine, France
| | - Ralf Jockers
- Inserm U1016, Institut Cochin, Dept Endocrinology, Metabolism and Diabetes, Paris, France.,CNRS UMR 8104, Paris, France.,University Paris Descartes, Sorbonne Paris Cité, Paris, France
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38
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Gulsevin A, Papke RL, Stokes C, Garai S, Thakur GA, Quadri M, Horenstein NA. Allosteric Agonism of α7 Nicotinic Acetylcholine Receptors: Receptor Modulation Outside the Orthosteric Site. Mol Pharmacol 2019; 95:606-614. [PMID: 30944209 DOI: 10.1124/mol.119.115758] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Accepted: 03/24/2019] [Indexed: 12/15/2022] Open
Abstract
Nicotinic acetylcholine receptors (nAChRs) are members of the Cys-loop superfamily of ligand-gated ion channels. Typically, channel activation follows the binding of agonists to the orthosteric binding sites of the receptor. α7 nAChRs have a very low probability of channel activation, which can be reversed by the binding of α7 selective positive allosteric modulators (PAMs) to putative sites within the transmembrane domains. Although typical PAMs, like PNU-120596, require coapplication of an orthosteric agonist to produce large channel activations, some, like GAT107 and B-973B [(S)-3-(3,4-difluorophenyl)-N-(1-(6-(4-(pyridin-2-yl)piperazin-1-yl)pyrazin-2-yl)ethyl)propanamide], are characterized as allosteric activating PAMs, which also bind to an allosteric activation (AA) site in the extracellular domain and activate the α7 ion channel by themselves. We had previously characterized N,N-diethyl-N'-phenylpiperazine analogs with various functions. In this work, we docked members of this family to a homology model of the α7 receptor extracellular domain. The compound 1,1-diethyl-4(naphthalene-2-yl)piperazin-1-ium (2NDEP) a weak partial agonist, showed particularly favorable docking and binding energies at the putative AA site of the receptor. We hypothesized that 2NDEP could couple with PAMs through the AA site. This hypothesis was tested with the α7 mutant C190A, which is not activated by orthosteric agonists but is effectively activated by GAT107. The results showed that 2NDEP acts as an allosteric agonist of α7C190A when coapplied with the PAM PNU-120596. Also, the allosteric activity was nearly abolished upon coapplication with the AA site-selective antagonist 2,3,5,6MP-TQS (cis-trans-4-(2,3,5,6-tetramethylphenyl)-3a,4,5,9b-tetrahydro-3H-cyclopenta[c]quinoline-8-sulfonamide), consistent with AA site involvement. Overall, our findings show a novel mode of agonism through an allosteric site in the extracellular domain of α7 nAChR.
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Affiliation(s)
- Alican Gulsevin
- Departments of Chemistry (A.G., M.Q., N.A.H.) and Pharmacology and Therapeutics (R.L.P, C.S., M.Q.), University of Florida, Gainesville, Florida; and Department of Pharmaceutical Sciences, School of Pharmacy, Bouvé College of Health Sciences, Northeastern University, Boston, Massachusetts (S.G., G.A.T.)
| | - Roger L Papke
- Departments of Chemistry (A.G., M.Q., N.A.H.) and Pharmacology and Therapeutics (R.L.P, C.S., M.Q.), University of Florida, Gainesville, Florida; and Department of Pharmaceutical Sciences, School of Pharmacy, Bouvé College of Health Sciences, Northeastern University, Boston, Massachusetts (S.G., G.A.T.)
| | - Clare Stokes
- Departments of Chemistry (A.G., M.Q., N.A.H.) and Pharmacology and Therapeutics (R.L.P, C.S., M.Q.), University of Florida, Gainesville, Florida; and Department of Pharmaceutical Sciences, School of Pharmacy, Bouvé College of Health Sciences, Northeastern University, Boston, Massachusetts (S.G., G.A.T.)
| | - Sumanta Garai
- Departments of Chemistry (A.G., M.Q., N.A.H.) and Pharmacology and Therapeutics (R.L.P, C.S., M.Q.), University of Florida, Gainesville, Florida; and Department of Pharmaceutical Sciences, School of Pharmacy, Bouvé College of Health Sciences, Northeastern University, Boston, Massachusetts (S.G., G.A.T.)
| | - Ganesh A Thakur
- Departments of Chemistry (A.G., M.Q., N.A.H.) and Pharmacology and Therapeutics (R.L.P, C.S., M.Q.), University of Florida, Gainesville, Florida; and Department of Pharmaceutical Sciences, School of Pharmacy, Bouvé College of Health Sciences, Northeastern University, Boston, Massachusetts (S.G., G.A.T.)
| | - Marta Quadri
- Departments of Chemistry (A.G., M.Q., N.A.H.) and Pharmacology and Therapeutics (R.L.P, C.S., M.Q.), University of Florida, Gainesville, Florida; and Department of Pharmaceutical Sciences, School of Pharmacy, Bouvé College of Health Sciences, Northeastern University, Boston, Massachusetts (S.G., G.A.T.)
| | - Nicole A Horenstein
- Departments of Chemistry (A.G., M.Q., N.A.H.) and Pharmacology and Therapeutics (R.L.P, C.S., M.Q.), University of Florida, Gainesville, Florida; and Department of Pharmaceutical Sciences, School of Pharmacy, Bouvé College of Health Sciences, Northeastern University, Boston, Massachusetts (S.G., G.A.T.)
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Spirova EN, Ivanov IA, Kasheverov IE, Kudryavtsev DS, Shelukhina IV, Garifulina AI, Son LV, Lummis SCR, Malca-Garcia GR, Bussmann RW, Hennig L, Giannis A, Tsetlin VI. Curare alkaloids from Matis Dart Poison: Comparison with d-tubocurarine in interactions with nicotinic, 5-HT3 serotonin and GABAA receptors. PLoS One 2019; 14:e0210182. [PMID: 30608952 PMCID: PMC6319706 DOI: 10.1371/journal.pone.0210182] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2018] [Accepted: 12/18/2018] [Indexed: 12/16/2022] Open
Abstract
Several novel bisbenzylisoquinoline alkaloids (BBIQAs) have recently been isolated from a Matis tribe arrow poison and shown by two-electrode voltage-clamp to inhibit mouse muscle nicotinic acetylcholine receptors (nAChR). Here, using radioligand assay with Aplysia californica AChBP and radioiodinated α-bungarotoxin ([125I]-αBgt), we show that BBIQA1, BBIQA2, and d-tubocurarine (d-TC) have similar affinities to nAChR orthosteric site. However, a competition with [125I]-αBgt for binding to the Torpedo californica muscle-type nAChR revealed that BBIQAs1, 2, and 3 are less potent (IC50s = 26.3, 8.75, and 17.0 μM) than d-TC (IC50 = 0.39 μM), while with α7 nAChR in GH4C1 cells, BBIQA1 was less potent that d-TC (IC50s = 162 μM and 7.77 μM, respectively), but BBIQA2 was similar (IC50 = 5.52 μM). In inhibiting the Ca2+ responses induced by acetylcholine in Neuro2a cells expressing the mouse adult α1β1εδ nAChR or human α7 nAChR, BBIQAs1 and 2 had similar potencies to d-TC (IC50s in the range 0.75-3.08 μM). Our data suggest that BBIQA1 and BBIQA2 can inhibit adult muscle α1β1εδ nAChR by both competitive and noncompetitive mechanisms. Further experiments on neuronal α3β2, α4β2, and α9α10 nAChRs, expressed in Xenopus laevis oocytes, showed that similar potencies for BBIQAs1, 2, and d-TC. With α3β2γ2 GABAAR currents were almost completely inhibited by d-TC at a high (100 μM) concentration, but BBIQAs1 and 2 were less potent (only 40-50% inhibition), whereas in competition with Alexa Fluor 546-α-cobratoxin for binding to α1β3γ2 GABAAR in Neuro2a cells, d-TC and these analogs had comparable affinities. Especially interesting effects of BBIQAs1 and 2 in comparison with d-TC were observed for 5-HT3AR: BBIQA1 and BBIQA2 were 5- and 87-fold less potent than d-TC (IC50 = 22.63 nM). Thus, our results reveal that these BBIQAs differ from d-TC in their potencies towards certain Cys-loop receptors, and we suggest that understanding the reasons behind this might be useful for future drug design.
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Affiliation(s)
- Ekaterina N. Spirova
- Department of Molecular Neuroimmune signaling, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Igor A. Ivanov
- Department of Molecular Neuroimmune signaling, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Igor E. Kasheverov
- Department of Molecular Neuroimmune signaling, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
- Sechenov First Moscow State Medical University, Institute of Molecular Medicine, Moscow, Russia
| | - Denis S. Kudryavtsev
- Department of Molecular Neuroimmune signaling, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Irina V. Shelukhina
- Department of Molecular Neuroimmune signaling, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Alexandra I. Garifulina
- Department of Molecular Neuroimmune signaling, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Lina V. Son
- Department of Molecular Neuroimmune signaling, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Sarah C. R. Lummis
- Department of Biochemistry, University of Cambridge, Cambridge, United Kingdom
| | - Gonzalo R. Malca-Garcia
- Department of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, University of Illinois at Chicago, Chicago, IL, United States of America
| | | | - Lothar Hennig
- Institut für Organische Chemie, Fakultät für Chemie und Mineralogie, Universität Leipzig, Leipzig, Germany
| | - Athanassios Giannis
- Institut für Organische Chemie, Fakultät für Chemie und Mineralogie, Universität Leipzig, Leipzig, Germany
| | - Victor I. Tsetlin
- Department of Molecular Neuroimmune signaling, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
- PhysBio of MEPhI, Moscow, Russia
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40
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Liu W, Li MD. Insights Into Nicotinic Receptor Signaling in Nicotine Addiction: Implications for Prevention and Treatment. Curr Neuropharmacol 2018; 16:350-370. [PMID: 28762314 PMCID: PMC6018190 DOI: 10.2174/1570159x15666170801103009] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2017] [Revised: 06/18/2017] [Accepted: 07/28/2017] [Indexed: 11/22/2022] Open
Abstract
BACKGROUND Nicotinic acetylcholine receptors (nAChRs) belong to the Cys-loop ligandgated ion-channel (LGIC) superfamily, which also includes the GABA, glycine, and serotonin receptors. Many nAChR subunits have been identified and shown to be involved in signal transduction on binding to them of either the neurotransmitter acetylcholine or exogenous ligands such as nicotine. The nAChRs are pentameric assemblies of homologous subunits surrounding a central pore that gates cation flux, and they are expressed at neuromuscular junctions throughout the nervous system. METHODS AND RESULTS Because different nAChR subunits assemble into a variety of pharmacologically distinct receptor subtypes, and different nAChRs are implicated in various physiological functions and pathophysiological conditions, nAChRs represent potential molecular targets for drug addiction and medical therapeutic research. This review intends to provide insights into recent advances in nAChR signaling, considering the subtypes and subunits of nAChRs and their roles in nicotinic cholinergic systems, including structure, diversity, functional allosteric modulation, targeted knockout mutations, and rare variations of specific subunits, and the potency and functional effects of mutations by focusing on their effects on nicotine addiction (NA) and smoking cessation (SC). Furthermore, we review the possible mechanisms of action of nAChRs in NA and SC based on our current knowledge. CONCLUSION Understanding these cellular and molecular mechanisms will lead to better translational and therapeutic operations and outcomes for the prevention and treatment of NA and other drug addictions, as well as chronic diseases, such as Alzheimer's and Parkinson's. Finally, we put forward some suggestions and recommendations for therapy and treatment of NA and other chronic diseases.
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Affiliation(s)
- Wuyi Liu
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Zhejiang University School of Medicine, Hangzhou, China.,School of Biological Sciences and Food Engineering, Fuyang Normal University, Fuyang, Anuhi 236041, China
| | - Ming D Li
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Zhejiang University School of Medicine, Hangzhou, China.,Research Center for Air Pollution and Health, Zhejiang University, Hangzhou, China.,Institute of NeuroImmune Pharmacology, Seton Hall University, South Orange, NJ, United States
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41
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Turani O, Hernando G, Corradi J, Bouzat C. Activation of Caenorhabditis elegans Levamisole-Sensitive and Mammalian Nicotinic Receptors by the Antiparasitic Bephenium. Mol Pharmacol 2018; 94:1270-1279. [PMID: 30190363 DOI: 10.1124/mol.118.113357] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Accepted: 08/29/2018] [Indexed: 11/22/2022] Open
Abstract
Nicotinic acetylcholine receptors (nAChRs) are ligand-gated ion channels involved in neuromuscular transmission. In nematodes, muscle nAChRs are targets of antiparasitic drugs. Bephenium is an anthelmintic compound whose molecular action in the free-living nematode Caenorhabditis elegans, which is a model for anthelmintic drug discovery, is poorly known. We explored the effect of bephenium on C. elegans locomotion and applied single-channel recordings to identify its molecular target, mechanism of action, and selectivity between mammalian and C. elegans nAChRs. As in parasites, bephenium paralyzes C. elegans A mutant strain lacking the muscle levamisole-sensitive nAChR (L-AChR) shows full resistance to bephenium, indicating that this receptor is the target site. Bephenium activates L-AChR channels from larvae muscle cells in the micromolar range. Channel activity is similar to that elicited by levamisole, appearing mainly as isolated brief openings. Our analysis revealed that bephenium is an agonist of L-AChR and an open-channel blocker at higher concentrations. It also activates mammalian muscle nAChRs. Opening events are significantly briefer than those elicited by ACh and do not appear in activation episodes at a range of concentrations, indicating that it is a very weak agonist of mammalian nAChRs. Recordings in the presence of ACh showed that bephenium acts as a voltage-dependent channel blocker and a low-affinity agonist. Molecular docking into homology-modeled binding-site interfaces represent the binding mode of bephenium that explains its partial agonism. Given the great diversity of helminth nAChRs and the overlap of their pharmacological profiles, unraveling the basis of drug receptor-selectivity will be required for rational design of anthelmintic drugs.
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Affiliation(s)
- Ornella Turani
- Instituto de Investigaciones Bioquímicas de Bahía Blanca (INIBIBB), Departamento de Biología, Bioquímica y Farmacia, Universidad Nacional del Sur-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Bahía Blanca, Argentina
| | - Guillermina Hernando
- Instituto de Investigaciones Bioquímicas de Bahía Blanca (INIBIBB), Departamento de Biología, Bioquímica y Farmacia, Universidad Nacional del Sur-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Bahía Blanca, Argentina
| | - Jeremías Corradi
- Instituto de Investigaciones Bioquímicas de Bahía Blanca (INIBIBB), Departamento de Biología, Bioquímica y Farmacia, Universidad Nacional del Sur-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Bahía Blanca, Argentina
| | - Cecilia Bouzat
- Instituto de Investigaciones Bioquímicas de Bahía Blanca (INIBIBB), Departamento de Biología, Bioquímica y Farmacia, Universidad Nacional del Sur-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Bahía Blanca, Argentina
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42
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Pan Z, Zhao M, Peng Y, Wang J. Functional divergence analysis of vertebrate neuronal nicotinic acetylcholine receptor subunits. J Biomol Struct Dyn 2018; 37:2938-2948. [PMID: 30044167 DOI: 10.1080/07391102.2018.1500945] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
Nicotinic acetylcholine receptors (nAChRs) are pentamers formed by subunits from a large multigene family and are highly variable in kinetic, electrophysiological and pharmacological properties. Due to the essential roles of nAChRs in many physiological procedures and diversity in function, identifying the function-related sites specific to each subunit is not only necessary to understand the properties of the receptors but also useful to design potential therapeutic compounds that target these macromolecules for treating a series of central neuronal disorders. By conducting a detailed function divergence analysis on nine neuronal nAChR subunits from representative vertebrate species, we revealed the existence of significant functional variation between most subunit pairs. Specifically, 44 unique residues were identified for the α7 subunit, while another 22 residues that were likely responsible for the specific features of other subunits were detected. By mapping these sites onto the 3 D structure of the human α7 subunit, a structure-function relationship profile was revealed. Our results suggested that the functional divergence related sites clustered in the ligand binding domain, the β2-β3 linker close to the N-terminal α-helix, the intracellular linkers between transmembrane domains, and the "transition zone" may have experienced altered evolutionary rates. The former two regions may be potential binding sites for the α7* subtype-specific allosteric modulators, while the latter region is likely to be subtype-specific allosteric modulations of the heteropentameric descendants such as the α4β2* nAChRs. Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Zhenhua Pan
- a School of Biomedical Engineering , Tianjin Medical University , Tianjin , China.,b Tianjin Key Laboratory of Lung Cancer Metastasis and Tumor Microenvironment , Tianjin Lung Cancer Institute, Tianjin Medical University General Hospital , Tianjin , China
| | - Mengwen Zhao
- a School of Biomedical Engineering , Tianjin Medical University , Tianjin , China
| | - Yonglin Peng
- a School of Biomedical Engineering , Tianjin Medical University , Tianjin , China
| | - Ju Wang
- a School of Biomedical Engineering , Tianjin Medical University , Tianjin , China
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43
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Bouzat C, Sine SM. Nicotinic acetylcholine receptors at the single-channel level. Br J Pharmacol 2018; 175:1789-1804. [PMID: 28261794 PMCID: PMC5979820 DOI: 10.1111/bph.13770] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2016] [Revised: 02/21/2017] [Accepted: 02/24/2017] [Indexed: 01/28/2023] Open
Abstract
Over the past four decades, the patch clamp technique and nicotinic ACh (nACh) receptors have established an enduring partnership. Like all good partnerships, each partner has proven significant in its own right, while their union has spurred innumerable advances in life science research. A member and prototype of the superfamily of pentameric ligand-gated ion channels, the nACh receptor is a chemo-electric transducer, binding ACh released from nerves and rapidly opening its channel to cation flow to elicit cellular excitation. A subject of a Nobel Prize in Physiology or Medicine, the patch clamp technique provides unprecedented resolution of currents through single ion channels in their native cellular environments. Here, focusing on muscle and α7 nACh receptors, we describe the extraordinary contribution of the patch clamp technique towards understanding how they activate in response to neurotransmitter, how subtle structural and mechanistic differences among nACh receptor subtypes translate into significant physiological differences, and how nACh receptors are being exploited as therapeutic drug targets. LINKED ARTICLES This article is part of a themed section on Nicotinic Acetylcholine Receptors. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v175.11/issuetoc/.
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Affiliation(s)
- Cecilia Bouzat
- Instituto de Investigaciones Bioquímicas de Bahía Blanca, INIBIBB (CONICET‐UNS), Departamento de Biología, Bioquímica y FarmaciaUniversidad Nacional del SurBahía BlancaArgentina
| | - Steven M Sine
- Receptor Biology Laboratory, Department of Physiology and Biomedical EngineeringMayo Clinic College of MedicineRochesterMN55905USA
- Department of NeurologyMayo Clinic College of MedicineRochesterMN55905USA
- Department of Pharmacology and Experimental TherapeuticsMayo Clinic College of MedicineRochesterMN55905USA
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44
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Targowska-Duda KM, Kaczor AA, Jozwiak K, Arias HR. Molecular interactions of type I and type II positive allosteric modulators with the human α7 nicotinic acetylcholine receptor: an in silico study. J Biomol Struct Dyn 2018; 37:411-439. [PMID: 29363414 DOI: 10.1080/07391102.2018.1427634] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The binding site locations and structural components for type I and type II positive allosteric modulators (PAMs) of the α7 nicotinic acetylcholine receptor (nAChR) have not been fully characterized yet. In this regard, homology models of the human α7 nAChR and hα7/m5-HT3A chimera, built using the crystal structure of the serotonin type 3A receptor (5-ΗΤ3ΑR), were used for molecular docking and molecular dynamics simulations to study the molecular interactions of selected type I (5-hydroxyindol, NS-1738, and LY-2087101) and type II (PNU-120596, PAM-2, and TBS-516) PAMs. The docking results indicate: (1) a site located in the extracellular domain (ECD) for type I PAMs such as NS-1738 and LY-2087101, but not for 5-HI; (2) an overlapping site in the ECD-transmembrane domain (TMD) junction for all studied PAMs. Additional docking results on the hα7/m5-HT3A chimera supported experimental results indicating that the ECD site might be relevant for type I PAM activity; and (3) two TMD sites, an intrasubunit site that recognizes type II PAMs, and an intersubunit pocket with high specificity for 5-HI (type I PAM). The in silico α7TSLMF mutant results support the view that M1-Ser223 and M3-Ile281 are key residues for the interaction of PAM-2 and PNU-120596 with the intrasubunit cavity. Our in silico results are in agreement with experimental data showing that the intrasubunit cavity is relevant for the activity of type II PAMs, and suggest that the ECD-TMD junction and intersubunit sites could be significant for the activity of type I PAMs.
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Affiliation(s)
| | - Agnieszka A Kaczor
- b Department of Synthesis and Chemical Technology of Pharmaceutical Substances with Computer Modeling Lab , Medical University of Lublin , Lublin , Poland.,c School of Pharmacy , University of Eastern Finland , Kuopio , Finland
| | - Krzysztof Jozwiak
- a Department of Biopharmacy , Medical University of Lublin , Lublin , Poland
| | - Hugo R Arias
- d Department of Basic Sciences , California Northstate University College of Medicine , Elk Grove , CA , USA
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45
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Competitive docking model for prediction of the human nicotinic acetylcholine receptor α7 binding of tobacco constituents. Oncotarget 2018; 9:16899-16916. [PMID: 29682193 PMCID: PMC5908294 DOI: 10.18632/oncotarget.24458] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2017] [Accepted: 02/01/2018] [Indexed: 12/21/2022] Open
Abstract
The detrimental health effects associated with tobacco use constitute a major public health concern. The addiction associated with nicotine found in tobacco products has led to difficulty in quitting among users. Nicotinic acetylcholine receptors (nAChRs) are the targets of nicotine and are responsible for addiction to tobacco products. However, it is unknown if the other >8000 tobacco constituents are addictive. Since it is time-consuming and costly to experimentally assess addictive potential of such larger number of chemicals, computationally predicting human nAChRs binding is important for in silico evaluation of addiction potential of tobacco constituents and needs structures of human nAChRs. Therefore, we constructed three-dimensional structures of the ligand binding domain of human nAChR α7 subtype and then developed a predictive model based on the constructed structures to predict human nAChR α7 binding activity of tobacco constituents. The predictive model correctly predicted 11 out of 12 test compounds to be binders of nAChR α7. The model is a useful tool for high-throughput screening of potential addictive tobacco constituents. These results could inform regulatory science research by providing a new validated predictive tool using cutting-edge computational methodology to high-throughput screen tobacco additives and constituents for their binding interaction with the human α7 nicotinic receptor. The tool represents a prediction model capable of screening thousands of chemicals found in tobacco products for addiction potential, which improves the understanding of the potential effects of additives.
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46
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Kuang G, Wang X, Halldin C, Nordberg A, Långström B, Ågren H, Tu Y. Theoretical study of the binding profile of an allosteric modulator NS-1738 with a chimera structure of the α7 nicotinic acetylcholine receptor. Phys Chem Chem Phys 2018; 18:28003-28009. [PMID: 27711412 DOI: 10.1039/c6cp02278b] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Potentiation of the function of the α7 nicotinic acetylcholine receptor (α7-nAChR) is believed to provide a possible way for the treatment of cholinergic system dysfunctions such as Alzheimer's disease and schizophrenia. Positive allosteric modulators (PAMs) are able to augment the peak current response of the endogenous agonist of α7-nAChR by binding to some allosteric sites. In this study, the binding profile of a potent type I PAM, NS-1738, with a chimera structure (termed α7-AChBP) constructed from the extracellular domain of α7-nAChR and an acetylcholine binding protein was investigated with molecular docking, molecular dynamics simulation, and free energy calculation methods. We found that NS-1738 could bind to three allosteric sites of α7-AChBP, namely, the top pocket, the vestibule pocket and the agonist sub-pocket. NS-1738 has moderate binding affinities (-6.76 to -9.15 kcal mol-1) at each allosteric site. The urea group is critical for binding and can form hydrogen-bond interactions with the protein. The bulky trifluoromethyl group also has a great impact on the binding modes and binding affinities. We believe that our study provides valuable insight into the binding profiles of type I PAMs with α7-nAChR and is helpful for the development of novel PAMs.
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Affiliation(s)
- Guanglin Kuang
- Division of Theoretical Chemistry and Biology, School of Biotechnology, Royal Institute of Technology (KTH), AlbaNova University Center, S-106 91, Stockholm, Sweden.
| | - Xu Wang
- Division of Theoretical Chemistry and Biology, School of Biotechnology, Royal Institute of Technology (KTH), AlbaNova University Center, S-106 91, Stockholm, Sweden.
| | - Christer Halldin
- Karolinska Institutet, Department of Clinical Neuroscience, Centre for Psychiatric Research, 171 76, Stockholm, Sweden
| | - Agneta Nordberg
- Department of Neurobiology, Care Sciences and Society, Center of Alzheimer Research, Translational Alzheimer Neurobiology, Karolinska University Hospital, Huddinge, S-141 86, Stockholm, Sweden
| | - Bengt Långström
- Department of Chemistry, Uppsala University, 751 23 Uppsala, Sweden
| | - Hans Ågren
- Division of Theoretical Chemistry and Biology, School of Biotechnology, Royal Institute of Technology (KTH), AlbaNova University Center, S-106 91, Stockholm, Sweden.
| | - Yaoquan Tu
- Division of Theoretical Chemistry and Biology, School of Biotechnology, Royal Institute of Technology (KTH), AlbaNova University Center, S-106 91, Stockholm, Sweden.
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47
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Delbart F, Brams M, Gruss F, Noppen S, Peigneur S, Boland S, Chaltin P, Brandao-Neto J, von Delft F, Touw WG, Joosten RP, Liekens S, Tytgat J, Ulens C. An allosteric binding site of the α7 nicotinic acetylcholine receptor revealed in a humanized acetylcholine-binding protein. J Biol Chem 2017; 293:2534-2545. [PMID: 29237730 PMCID: PMC5818190 DOI: 10.1074/jbc.m117.815316] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2017] [Revised: 10/24/2017] [Indexed: 11/06/2022] Open
Abstract
Nicotinic acetylcholine receptors (nAChRs) belong to the family of pentameric ligand-gated ion channels and mediate fast excitatory transmission in the central and peripheral nervous systems. Among the different existing receptor subtypes, the homomeric α7 nAChR has attracted considerable attention because of its possible implication in several neurological and psychiatric disorders, including cognitive decline associated with Alzheimer's disease or schizophrenia. Allosteric modulators of ligand-gated ion channels are of particular interest as therapeutic agents, as they modulate receptor activity without affecting normal fluctuations of synaptic neurotransmitter release. Here, we used X-ray crystallography and surface plasmon resonance spectroscopy of α7-acetylcholine-binding protein (AChBP), a humanized chimera of a snail AChBP, which has 71% sequence similarity with the extracellular ligand-binding domain of the human α7 nAChR, to investigate the structural determinants of allosteric modulation. We extended previous observations that an allosteric site located in the vestibule of the receptor offers an attractive target for receptor modulation. We introduced seven additional humanizing mutations in the vestibule-located binding site of AChBP to improve its suitability as a model for studying allosteric binding. Using a fragment-based screening approach, we uncovered an allosteric binding site located near the β8-β9 loop, which critically contributes to coupling ligand binding to channel opening in human α7 nAChR. This work expands our understanding of the topology of allosteric binding sites in AChBP and, by extrapolation, in the human α7 nAChR as determined by electrophysiology measurements. Our insights pave the way for drug design strategies targeting nAChRs involved in ion channel-mediated disorders.
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Affiliation(s)
- Florian Delbart
- From the Department of Cellular and Molecular Medicine, Laboratory of Structural Neurobiology, Faculty of Medicine, KU Leuven, 3000 Leuven, Belgium
| | - Marijke Brams
- From the Department of Cellular and Molecular Medicine, Laboratory of Structural Neurobiology, Faculty of Medicine, KU Leuven, 3000 Leuven, Belgium
| | - Fabian Gruss
- From the Department of Cellular and Molecular Medicine, Laboratory of Structural Neurobiology, Faculty of Medicine, KU Leuven, 3000 Leuven, Belgium
| | - Sam Noppen
- the Department of Microbiology and Immunology, Laboratory of Virology and Chemotherapy, Rega Institute for Medical Research, KU Leuven, 3000 Leuven, Belgium
| | - Steve Peigneur
- the Laboratory of Toxicology and Pharmacology, Faculty of Pharmaceutical Sciences, KU Leuven, 3000 Leuven, Belgium
| | - Sandro Boland
- the Center for Innovation and Stimulation of Drug Discovery Leuven, Cistim Leuven vzw, 3001 Heverlee, Belgium
| | - Patrick Chaltin
- the Center for Innovation and Stimulation of Drug Discovery Leuven, Cistim Leuven vzw, 3001 Heverlee, Belgium.,the Center for Innovation and Stimulation of Drug Discovery Leuven and Center for Drug Design and Discovery, KU Leuven, 3001 Heverlee, Belgium
| | - Jose Brandao-Neto
- Diamond Light Source Ltd., Harwell Science and Innovation Campus, Didcot OX11 0QX, United Kingdom, and
| | - Frank von Delft
- Diamond Light Source Ltd., Harwell Science and Innovation Campus, Didcot OX11 0QX, United Kingdom, and
| | - Wouter G Touw
- the Division of Biochemistry, Netherlands Cancer Institute, 1066CX Amsterdam, The Netherlands
| | - Robbie P Joosten
- the Division of Biochemistry, Netherlands Cancer Institute, 1066CX Amsterdam, The Netherlands
| | - Sandra Liekens
- the Department of Microbiology and Immunology, Laboratory of Virology and Chemotherapy, Rega Institute for Medical Research, KU Leuven, 3000 Leuven, Belgium
| | - Jan Tytgat
- the Laboratory of Toxicology and Pharmacology, Faculty of Pharmaceutical Sciences, KU Leuven, 3000 Leuven, Belgium
| | - Chris Ulens
- From the Department of Cellular and Molecular Medicine, Laboratory of Structural Neurobiology, Faculty of Medicine, KU Leuven, 3000 Leuven, Belgium,
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Nemecz Á, Prevost MS, Menny A, Corringer PJ. Emerging Molecular Mechanisms of Signal Transduction in Pentameric Ligand-Gated Ion Channels. Neuron 2017; 90:452-70. [PMID: 27151638 DOI: 10.1016/j.neuron.2016.03.032] [Citation(s) in RCA: 154] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2015] [Revised: 01/07/2016] [Accepted: 03/24/2016] [Indexed: 10/21/2022]
Abstract
Nicotinic acetylcholine, serotonin type 3, γ-amminobutyric acid type A, and glycine receptors are major players of human neuronal communication. They belong to the family of pentameric ligand-gated ion channels, sharing a highly conserved modular 3D structure. Recently, high-resolution structures of both open- and closed-pore conformations have been solved for a bacterial, an invertebrate, and a vertebrate receptor in this family. These data suggest that a common gating mechanism occurs, coupling neurotransmitter binding to pore opening, but they also pinpoint significant differences among subtypes. In this Review, we summarize the structural and functional data in light of these gating models and speculate about their mechanistic consequences on ion permeation, pathological mutations, as well as functional regulation by orthosteric and allosteric effectors.
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Affiliation(s)
- Ákos Nemecz
- Channel-Receptors Unit, Institut Pasteur, 75015 Paris, France; CNRS UMR 3571, 75015 Paris, France
| | - Marie S Prevost
- Institute of Structural and Molecular Biology, University College London and Birkbeck, Malet Street, London WC1E 7HX, UK
| | - Anaïs Menny
- Channel-Receptors Unit, Institut Pasteur, 75015 Paris, France; CNRS UMR 3571, 75015 Paris, France; Université Pierre et Marie Curie (UPMC), Cellule Pasteur, 75005 Paris, France
| | - Pierre-Jean Corringer
- Channel-Receptors Unit, Institut Pasteur, 75015 Paris, France; CNRS UMR 3571, 75015 Paris, France.
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Tabassum N, Ma Q, Wu G, Jiang T, Yu R. Exploring the binding energy profiles of full agonists, partial agonists, and antagonists of the α7 nicotinic acetylcholine receptor. J Mol Model 2017; 23:251. [PMID: 28770361 DOI: 10.1007/s00894-017-3419-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2017] [Accepted: 07/13/2017] [Indexed: 02/02/2023]
Abstract
Nicotinic acetylcholine receptors (nAChRs) belong to the Cys-loop receptor family and are important drug targets for the treatment of neurological diseases. However, the precise determinants of the binding efficacies of ligands for these receptors are unclear. Therefore, in this study, the binding energy profiles of various ligands (full agonists, partial agonists, and antagonists) were quantified by docking those ligands with structural ensembles of the α7 nAChR exhibiting different degrees of C-loop closure. This approximate treatment of interactions suggested that full agonists, partial agonists, and antagonists of the α7 nAChR possess distinctive binding energy profiles. Results from docking revealed that ligand binding efficacy may be related to the capacity of the ligand to stabilize conformational states with a closed C loop.
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Affiliation(s)
- Nargis Tabassum
- Key Laboratory of Marine Drugs, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, 5 Yushan Road, Qingdao, 266003, China.,Laboratory for Marine Drugs and Bioproducts, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266003, China
| | - Qianyun Ma
- Key Laboratory of Marine Drugs, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, 5 Yushan Road, Qingdao, 266003, China.,Laboratory for Marine Drugs and Bioproducts, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266003, China
| | - Guanzhao Wu
- Key Laboratory of Marine Drugs, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, 5 Yushan Road, Qingdao, 266003, China.,Laboratory for Marine Drugs and Bioproducts, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266003, China
| | - Tao Jiang
- Key Laboratory of Marine Drugs, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, 5 Yushan Road, Qingdao, 266003, China.,Laboratory for Marine Drugs and Bioproducts, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266003, China
| | - Rilei Yu
- Key Laboratory of Marine Drugs, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, 5 Yushan Road, Qingdao, 266003, China. .,Laboratory for Marine Drugs and Bioproducts, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266003, China.
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Murgueitio MS, Ebner S, Hörtnagl P, Rakers C, Bruckner R, Henneke P, Wolber G, Santos-Sierra S. Enhanced immunostimulatory activity of in silico discovered agonists of Toll-like receptor 2 (TLR2). Biochim Biophys Acta Gen Subj 2017; 1861:2680-2689. [PMID: 28734965 DOI: 10.1016/j.bbagen.2017.07.011] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2017] [Revised: 07/10/2017] [Accepted: 07/18/2017] [Indexed: 02/04/2023]
Abstract
BACKGROUND Emergent therapies in anticancer vaccination use Toll-like receptors (TLRs) agonists as dendritic cell (DC) vaccine adjuvants. DCs from the patient are isolated, stimulated with TLR agonists and tumor antigens ex vivo and then infused back into the patient. Although some TLR ligands have been tested in clinical trials, novel TLR agonists with improved immunomodulatory properties are essential to optimize treatment success. We report on the discovery of small-molecule TLR2 agonists, with favorable properties as synthetic adjuvants. METHODS We performed a shape- and featured-based similarity virtual screening against a commercially available compound library. The selected virtual hits were experimentally tested in TLR2-reporter cells and their activity in phagocytes and DCs was characterized. A binding model of the compounds to TLR2 (docking studies) was proposed. RESULTS Through a virtual screening approach against a library of three million compounds four virtual hits (AG1, AG2, AG3, AG4) were found to synergistically augment the NF-kB activation induced by the lipopeptide ligand Pam3CSK4 in luciferase reporter assays using HEK293-TLR2 cells. Biacore experiments indicated that AG1-AG4 are ago-allosteric modulators of TLR2 and AG2 bound TLR2 with high affinity (KD 0.8μM). The compounds induced TNF-α production in human peripheral blood mononuclear cells (PBMCs) and they activated DCs as indicated by IL-12 production and upregulation of CD83/CD86. CONCLUSIONS Following a combined in silico/in vitro approach we have discovered TLR2-agonists (AG1-AG4) that activate human and mouse immune cells. GENERAL SIGNIFICANCE We introduce four novel TLR2 ago-allosteric modulators that stimulate myeloid cell activity and constitute promising candidates as synthetic adjuvants.
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Affiliation(s)
- M S Murgueitio
- Pharmaceutical Chemistry, Institute of Pharmacy, Freie Universität Berlin, Königin-Luise Str. 2-4, 14195 Berlin, Germany
| | - S Ebner
- Department of Visceral, Transplant and Thoracic Surgery, Center of Operative Medicine, Medical University Innsbruck, Innrain 66, 6020 Innsbruck, Austria
| | - P Hörtnagl
- Central Institute of Blood Transfusion and Immunology, Medical University Innsbruck, Anichstrasse 35, 6020 Innsbruck, Austria
| | - C Rakers
- Pharmaceutical Chemistry, Institute of Pharmacy, Freie Universität Berlin, Königin-Luise Str. 2-4, 14195 Berlin, Germany
| | - R Bruckner
- Section of Biochemical Pharmacology, Medical University Innsbruck, Peter Mayr Str.1, 6020 Innsbruck, Austria
| | - P Henneke
- Center for Chronic Immunodeficiency (CCI) and Center for Pediatrics and Adolescent Medicine, Medical Center, University of Freiburg, Faculty of Medicine, Breisacher Straße 115, 79106 Freiburg, Germany
| | - G Wolber
- Pharmaceutical Chemistry, Institute of Pharmacy, Freie Universität Berlin, Königin-Luise Str. 2-4, 14195 Berlin, Germany
| | - S Santos-Sierra
- Section of Biochemical Pharmacology, Medical University Innsbruck, Peter Mayr Str.1, 6020 Innsbruck, Austria.
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