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Dallanoce C, Richter K, Stokes C, Papotto C, Andleeb H, Thakur GA, Kerr A, Grau V, Papke RL. New Alpha9 nAChR Ligands Based on a 5-(Quinuclidin-3-ylmethyl)-1,2,4-oxadiazole Scaffold. ACS Chem Neurosci 2024; 15:827-843. [PMID: 38335726 DOI: 10.1021/acschemneuro.3c00720] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2024] Open
Abstract
Several lines of evidence have indicated that nicotinic acetylcholine receptors (nAChR) that contain α9 subunits, probably in combination with α10 subunits, may be valuable targets for the management of pain associated with inflammatory diseases through a cholinergic anti-inflammatory system (CAS), which has also been associated with α7 nAChR. Both α7- and α9-containing neuronal nAChR can be pharmacologically distinguished from the high-affinity nicotinic receptors of the brain by their sensitivity to α-bungarotoxin, but in other ways, they have quite distinct pharmacological profiles. The early association of α7 with CAS led to the development of numerous new ligands, variously characterized as α7 agonists, partial agonists, or silent agonists that desensitized α7 receptors without activation. Subsequent reinvestigation of one such family of α7 ligands based on an N,N-diethyl-N'-phenylpiperazine scaffold led to the identification of potent agonists and antagonists for α9. In this paper, we characterize the α9/α10 activity of a series of compounds based on a 5-(quinuclidin-3-ylmethyl)-1,2,4-oxadiazole (QMO) scaffold and identify two new potent ligands of α9, QMO-28, an agonist, and QMO-17, an antagonist. We separated the stereoisomers of these compounds to identify the most potent agonist and discovered that only the 3R isomer of QMO-17 was an α9 antagonist, permitting an in silico model of α9 antagonism to be developed. The α9 activity of these compounds was confirmed to be potentially useful for CAS management of inflammatory pain in cell-based assays of cytokine release.
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Affiliation(s)
- Clelia Dallanoce
- Department of Pharmaceutical Sciences, Medicinal Chemistry Section "Pietro Pratesi″, University of Milan, Via L. Mangiagalli 25, 20133 Milan, Italy
| | - Katrin Richter
- Department of General and Thoracic Surgery, Laboratory of Experimental Surgery, Justus-Liebig-University, German Center for Lung Research [DZL], Cardio-Pulmonary Institute [CPI], Giessen 35390, Germany
| | - Clare Stokes
- Department of Pharmacology and Therapeutics, University of Florida, PO Box 100267, Gainesville, Florida 32610 United States
| | - Claudio Papotto
- Department of Pharmaceutical Sciences, Medicinal Chemistry Section "Pietro Pratesi″, University of Milan, Via L. Mangiagalli 25, 20133 Milan, Italy
| | - Hina Andleeb
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, Bouvé College of Health Sciences, Northeastern University, Boston, Massachusetts 02115, United States
| | - Ganesh A Thakur
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, Bouvé College of Health Sciences, Northeastern University, Boston, Massachusetts 02115, United States
| | - Andrew Kerr
- United States Naval Research Laboratory, 6920 Washington, District of Columbia, United States
| | - Veronika Grau
- Department of General and Thoracic Surgery, Laboratory of Experimental Surgery, Justus-Liebig-University, German Center for Lung Research [DZL], Cardio-Pulmonary Institute [CPI], Giessen 35390, Germany
| | - Roger L Papke
- Department of Pharmacology and Therapeutics, University of Florida, PO Box 100267, Gainesville, Florida 32610 United States
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Li X, Tae HS, Chen S, Yousuf A, Huang L, Zhang J, Jiang T, Adams DJ, Yu R. Dual Antagonism of α9α10 nAChR and GABA B Receptor-Coupled Ca V2.2 Channels by an Analgesic αO-Conotoxin Analogue. J Med Chem 2024; 67:971-987. [PMID: 38217860 DOI: 10.1021/acs.jmedchem.3c00979] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2024]
Abstract
Pain severely affects the physical and mental health of patients. The need to develop nonopioid analgesic drugs to meet medical demands is urgent. In this study, we designed a truncated analogue of αO-conotoxin, named GeX-2, based on disulfide-bond deletion and sequence truncation. GeX-2 retained the potency of its parent peptide at the human α9α10 nAChR and exhibited potent inhibitory activity at CaV2.2 channels via activation of the GABAB receptor (GABABR). Importantly, GeX-2 significantly alleviated pain in the rat model of chronic constriction injury. The dual inhibition of GeX-2 at both α9α10 nAChRs and CaV2.2 channels is speculated to synergistically mediate the potent analgesic effects. Results from site-directed mutagenesis assay and computational modeling suggest that GeX-2 preferentially interacts with the α10(+)α10(-) binding site of α9α10 nAChR and favorably binds to the top region of the GABABR2 subunit. The study offers vital insights into the molecular action mechanism of GeX-2, demonstrating its potential as a novel nonopioid analgesic.
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Affiliation(s)
- Xiao Li
- 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
| | - Han-Shen Tae
- Illawarra Health and Medical Research Institute (IHMRI), Faculty of Science, Medicine and Health, University of Wollongong, Wollongong, New South Wales 2522, Australia
| | - Shen Chen
- 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
| | - Arsalan Yousuf
- Illawarra Health and Medical Research Institute (IHMRI), Faculty of Science, Medicine and Health, University of Wollongong, Wollongong, New South Wales 2522, Australia
| | - Linhong Huang
- 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
| | - Jinghui Zhang
- 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
| | - David J Adams
- Illawarra Health and Medical Research Institute (IHMRI), Faculty of Science, Medicine and Health, University of Wollongong, Wollongong, New South Wales 2522, Australia
| | - 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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Mares C, Udrea AM, Buiu C, Staicu A, Avram S. Therapeutic Potentials of Aconite-like Alkaloids: Bioinformatics and Experimental Approaches. Mini Rev Med Chem 2024; 24:159-175. [PMID: 36994982 DOI: 10.2174/1389557523666230328153417] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Revised: 12/19/2022] [Accepted: 12/28/2022] [Indexed: 03/31/2023]
Abstract
Compounds from plants that are used in traditional medicine may have medicinal properties. It is well known that plants belonging to the genus Aconitum are highly poisonous. Utilizing substances derived from Aconitum sp. has been linked to negative effects. In addition to their toxicity, the natural substances derived from Aconitum species may have a range of biological effects on humans, such as analgesic, anti-inflammatory, and anti-cancer characteristics. Multiple in silico, in vitro, and in vivo studies have demonstrated the effectiveness of their therapeutic effects. In this review, the clinical effects of natural compounds extracted from Aconitum sp., focusing on aconitelike alkaloids, are investigated particularly by bioinformatics tools, such as the quantitative structure- activity relationship method, molecular docking, and predicted pharmacokinetic and pharmacodynamic profiles. The experimental and bioinformatics aspects of aconitine's pharmacogenomic profile are discussed. Our review could help shed light on the molecular mechanisms of Aconitum sp. compounds. The effects of several aconite-like alkaloids, such as aconitine, methyllycacintine, or hypaconitine, on specific molecular targets, including voltage-gated sodium channels, CAMK2A and CAMK2G during anesthesia, or BCL2, BCL-XP, and PARP-1 receptors during cancer therapy, are evaluated. According to the reviewed literature, aconite and aconite derivatives have a high affinity for the PARP-1 receptor. The toxicity estimations for aconitine indicate hepatotoxicity and hERG II inhibitor activity; however, this compound is not predicted to be AMES toxic or an hERG I inhibitor. The efficacy of aconitine and its derivatives in treating many illnesses has been proven experimentally. Toxicity occurs as a result of the high ingested dose; however, the usage of this drug in future research is based on the small quantity of an active compound that fulfills a therapeutic role.
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Affiliation(s)
- Catalina Mares
- Department of Anatomy, Animal Physiology and Biophysics, Faculty of Biology, University of Bucharest, 050095, Bucharest, Romania
| | - Ana-Maria Udrea
- Laser Department, National Institute for Laser, Plasma and Radiation Physics, Magurele, 077125, Romania
- Earth, Environmental and Life Sciences Section, Research Institute of the University of Bucharest, University of Bucharest, Bucharest, 50567, Romania
| | - Catalin Buiu
- Department of Automatic Control and Systems Engineering, Politehnica University of Bucharest, Bucharest, 060042, Romania
| | - Angela Staicu
- Laser Department, National Institute for Laser, Plasma and Radiation Physics, Magurele, 077125, Romania
| | - Speranta Avram
- Department of Anatomy, Animal Physiology and Biophysics, Faculty of Biology, University of Bucharest, 050095, Bucharest, Romania
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Tsetlin V, Shelukhina I, Kozlov S, Kasheverov I. Fifty Years of Animal Toxin Research at the Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry RAS. Int J Mol Sci 2023; 24:13884. [PMID: 37762187 PMCID: PMC10530976 DOI: 10.3390/ijms241813884] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2023] [Revised: 09/04/2023] [Accepted: 09/06/2023] [Indexed: 09/29/2023] Open
Abstract
This review covers briefly the work carried out at our institute (IBCh), in many cases in collaboration with other Russian and foreign laboratories, for the last 50 years. It discusses the discoveries and studies of various animal toxins, including protein and peptide neurotoxins acting on the nicotinic acetylcholine receptors (nAChRs) and on other ion channels. Among the achievements are the determination of the primary structures of the α-bungarotoxin-like three-finger toxins (TFTs), covalently bound dimeric TFTs, glycosylated cytotoxin, inhibitory cystine knot toxins (ICK), modular ICKs, and such giant molecules as latrotoxins and peptide neurotoxins from the snake, as well as from other animal venoms. For a number of toxins, spatial structures were determined, mostly by 1H-NMR spectroscopy. Using this method in combination with molecular modeling, the molecular mechanisms of the interactions of several toxins with lipid membranes were established. In more detail are presented the results of recent years, among which are the discovery of α-bungarotoxin analogs distinguishing the two binding sites in the muscle-type nAChR, long-chain α-neurotoxins interacting with α9α10 nAChRs and with GABA-A receptors, and the strong antiviral effects of dimeric phospholipases A2. A summary of the toxins obtained from arthropod venoms includes only highly cited works describing the molecules' success story, which is associated with IBCh. In marine animals, versatile toxins in terms of structure and molecular targets were discovered, and careful work on α-conotoxins differing in specificity for individual nAChR subtypes gave information about their binding sites.
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Affiliation(s)
- Victor Tsetlin
- Department of Molecular Neuroimmune Signaling, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 16/10 Miklukho-Maklay Str., 117997 Moscow, Russia; (I.S.); (I.K.)
| | - Irina Shelukhina
- Department of Molecular Neuroimmune Signaling, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 16/10 Miklukho-Maklay Str., 117997 Moscow, Russia; (I.S.); (I.K.)
| | - Sergey Kozlov
- Department of Molecular Neurobiology, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 16/10 Miklukho-Maklay Str., 117997 Moscow, Russia;
| | - Igor Kasheverov
- Department of Molecular Neuroimmune Signaling, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 16/10 Miklukho-Maklay Str., 117997 Moscow, Russia; (I.S.); (I.K.)
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Pechlivanidou M, Ninou E, Karagiorgou K, Tsantila A, Mantegazza R, Francesca A, Furlan R, Dudeck L, Steiner J, Tzartos J, Tzartos S. Autoimmunity to Neuronal Nicotinic Acetylcholine Receptors. Pharmacol Res 2023; 192:106790. [PMID: 37164280 DOI: 10.1016/j.phrs.2023.106790] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/04/2023] [Revised: 04/30/2023] [Accepted: 05/05/2023] [Indexed: 05/12/2023]
Abstract
Nicotinic acetylcholine receptors (nAChRs) are widely expressed in many and diverse cell types, participating in various functions of cells, tissues and systems. In this review, we focus on the autoimmunity against neuronal nAChRs, the specific autoantibodies and their mechanisms of pathological action in selected autoimmune diseases. We summarize the current relevant knowledge from human diseases as well as from experimental models of autoimmune neurological disorders related to antibodies against neuronal nAChR subunits. Despite the well-studied high immunogenicity of the muscle nAChRs where autoantibodies are the main pathogen of myasthenia gravis, autoimmunity to neuronal nAChRs seems infrequent, except for the autoantibodies to the ganglionic receptor, the α3 subunit containing nAChR (α3-nAChR), which are detected and are likely pathogenic in Autoimmune Autonomic Ganglionopathy (AAG). We describe the detection, presence and function of these antibodies and especially the recent development of a cell-based assay (CBA) which, contrary to until recently available assays, is highly specific for AAG. Rare reports of autoantibodies to the other neuronal nAChR subtypes include a few cases of antibodies to α7 and/or α4β2 nAChRs in Rasmussen encephalitis, schizophrenia, autoimmune meningoencephalomyelitis, and in some myasthenia gravis patients with concurrent CNS symptoms. Neuronal-type nAChRs are also present in several non-excitable tissues, however the presence and possible role of antibodies against them needs further verification. It is likely that the future development of more sensitive and disease-specific assays would reveal that neuronal nAChR autoantibodies are much more frequent and may explain the mechanisms of some seronegative autoimmune diseases.
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Affiliation(s)
| | | | - Katerina Karagiorgou
- Tzartos NeuroDiagnostics, Athens, Greece; Department of Biochemistry and Biotechnology, University of Thessaly, Larissa, Greece
| | | | - Renato Mantegazza
- Neuroimmunology and Neuromuscular Diseases Unit, Fondazione I.R.C.C.S. Istituto Neurologico Carlo Besta, Milan, Italy
| | - Andreetta Francesca
- Neuroimmunology and Neuromuscular Diseases Unit, Fondazione I.R.C.C.S. Istituto Neurologico Carlo Besta, Milan, Italy
| | - Raffaello Furlan
- Department of Biomedical Sciences, Humanitas University, Pieve Emanuele, Rozzano, Milan, Italy; Clinical and Research Center - IRCCS, Humanitas University, Rozzano, Milan, Italy
| | - Leon Dudeck
- Department of Psychiatry and Psychotherapy, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany; Laboratory of Translational Psychiatry, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany
| | - Johann Steiner
- Department of Psychiatry and Psychotherapy, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany; Laboratory of Translational Psychiatry, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany; Center for Behavioral Brain Sciences (CBBS), Magdeburg, Germany; Center for Health and Medical Prevention (CHaMP), Magdeburg, Germany; German Center for Mental Health DZPG, Center for Intervention and Research on Adaptive and Maladaptive Brain Circuits Underlying Mental Health C-I-R-C, Halle-Jena-Magdeburg, Germany
| | - John Tzartos
- 2(nd) Department of Neurology, School of Medicine, National and Kapodistrian University of Athens, "Attikon" University Hospital, Athens, Greece.
| | - Socrates Tzartos
- Tzartos NeuroDiagnostics, Athens, Greece; Department of Neurobiology, Hellenic Pasteur Institute, Athens, Greece; Department of Pharmacy, University of Patras, Patras, Greece.
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Barrantes FJ. Structure and function meet at the nicotinic acetylcholine receptor-lipid interface. Pharmacol Res 2023; 190:106729. [PMID: 36931540 DOI: 10.1016/j.phrs.2023.106729] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/04/2023] [Revised: 03/08/2023] [Accepted: 03/13/2023] [Indexed: 03/17/2023]
Abstract
The nicotinic acetylcholine receptor (nAChR) is a transmembrane protein that mediates fast intercellular communication in response to the endogenous neurotransmitter acetylcholine. It is the best characterized and archetypal molecule in the superfamily of pentameric ligand-gated ion channels (pLGICs). As a typical transmembrane macromolecule, it interacts extensively with its vicinal lipid microenvironment. Experimental evidence provides a wealth of information on receptor-lipid crosstalk: the nAChR exerts influence on its immediate membrane environment and conversely, the lipid moiety modulates ligand binding, affinity state transitions and gating of ion translocation functions of the receptor protein. Recent cryogenic electron microscopy (cryo-EM) studies have unveiled the occurrence of sites for phospholipids and cholesterol on the lipid-exposed regions of neuronal and electroplax nAChRs, confirming early spectroscopic and affinity labeling studies demonstrating the close contact of lipid molecules with the receptor transmembrane segments. This new data provides structural support to the postulated "lipid sensor" ability displayed by the outer ring of M4 transmembrane domains and their modulatory role on nAChR function, as we postulated a decade ago. Borrowing from the best characterized nAChR, the electroplax (muscle-type) receptor, and exploiting new structural information on the neuronal nAChR, it is now possible to achieve an improved depiction of these sites. In combination with site-directed mutagenesis, single-channel electrophysiology, and molecular dynamics studies, the new structural information delivers a more comprehensive portrayal of these lipid-sensitive loci, providing mechanistic explanations for their ability to modulate nAChR properties and raising the possibility of targetting them in disease.
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Affiliation(s)
- Francisco J Barrantes
- Laboratory of Molecular Neurobiology, Biomedical Research Institute, Faculty of Medical Sciences, Pontifical Catholic University of Argentina (UCA) - Argentine Scientific & Technol. Research Council (CONICET), Av. Alicia Moreau de Justo 1600, C1107AAZ Buenos Aires, Argentina.
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Abstract
Within the superfamily of pentameric ligand-gated ion channels, cholinergic nicotinic receptors (nAChRs) were classically identified to mediate synaptic transmission in the nervous system and the neuromuscular junction. The α9 and α10 nAChR subunits were the last ones to be identified. Surprisingly, they do not fall into the dichotomic neuronal/muscle classification of nAChRs. They assemble into heteropentamers with a well-established function as canonical ion channels in inner ear hair cells, where they mediate central nervous system control of auditory and vestibular sensory processing. The present review includes expression, pharmacological, structure-function, molecular evolution and pathophysiological studies, that define receptors composed from α9 and α10 subunits as distant and distinct members within the nAChR family. Thus, although α9 and α10 were initially included within the neuronal subdivision of nAChR subunits, they form a distinct clade within the phylogeny of nAChRs. Following the classification of nAChR subunits based on their main synaptic site of action, α9 and α10 should receive a name in their own right.
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Affiliation(s)
- Ana Belén Elgoyhen
- Instituto de Investigaciones en Ingeniería Genética y Biología Molecular "Dr. Héctor N. Torres" (INGEBI), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Vuelta de Obligado 2490, Buenos Aires 1428, Argentina.
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Nys M, Zarkadas E, Brams M, Mehregan A, Kambara K, Kool J, Casewell NR, Bertrand D, Baenziger JE, Nury H, Ulens C. The molecular mechanism of snake short-chain α-neurotoxin binding to muscle-type nicotinic acetylcholine receptors. Nat Commun 2022; 13:4543. [PMID: 35927270 PMCID: PMC9352773 DOI: 10.1038/s41467-022-32174-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Accepted: 07/20/2022] [Indexed: 11/11/2022] Open
Abstract
Bites by elapid snakes (e.g. cobras) can result in life-threatening paralysis caused by venom neurotoxins blocking neuromuscular nicotinic acetylcholine receptors. Here, we determine the cryo-EM structure of the muscle-type Torpedo receptor in complex with ScNtx, a recombinant short-chain α-neurotoxin. ScNtx is pinched between loop C on the principal subunit and a unique hairpin in loop F on the complementary subunit, thereby blocking access to the neurotransmitter binding site. ScNtx adopts a binding mode that is tilted toward the complementary subunit, forming a wider network of interactions than those seen in the long-chain α-Bungarotoxin complex. Certain mutations in ScNtx at the toxin-receptor interface eliminate inhibition of neuronal α7 nAChRs, but not of human muscle-type receptors. These observations explain why ScNtx binds more tightly to muscle-type receptors than neuronal receptors. Together, these data offer a framework for understanding subtype-specific actions of short-chain α-neurotoxins and inspire strategies for design of new snake antivenoms.
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Affiliation(s)
- Mieke Nys
- Laboratory of Structural Neurobiology, Department of Cellular and Molecular Medicine, Faculty of Medicine, KU Leuven, 3000, Leuven, Belgium.
| | - Eleftherios Zarkadas
- University Grenoble Alpes, CNRS, CEA, IBS, F-38000, Grenoble, France
- University Grenoble Alpes, CNRS, CEA, EMBL, ISBG, F-38000, Grenoble, France
| | - Marijke Brams
- Laboratory of Structural Neurobiology, Department of Cellular and Molecular Medicine, Faculty of Medicine, KU Leuven, 3000, Leuven, Belgium
| | - Aujan Mehregan
- Laboratory of Structural Neurobiology, Department of Cellular and Molecular Medicine, Faculty of Medicine, KU Leuven, 3000, Leuven, Belgium
| | | | - Jeroen Kool
- AIMMS Division of BioMolecular Analysis, Vrije Universiteit Amsterdam, 1081, HV, Amsterdam, Netherlands
| | - Nicholas R Casewell
- Centre for Snakebite Research & Interventions, Liverpool School of Tropical Medicine, L3 5QA, Liverpool, UK
| | | | - John E Baenziger
- Department of Biochemistry, Microbiology, and Immunology, University of Ottawa, Ottawa, ON, K1H 8M5, Canada
| | - Hugues Nury
- University Grenoble Alpes, CNRS, CEA, IBS, F-38000, Grenoble, France
| | - Chris Ulens
- Laboratory of Structural Neurobiology, Department of Cellular and Molecular Medicine, Faculty of Medicine, KU Leuven, 3000, Leuven, Belgium.
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Giastas P, Papakyriakou A, Tsafaras G, Tzartos SJ, Zouridakis M. Structural Insights into the Role of β3 nAChR Subunit in the Activation of Nicotinic Receptors. Molecules 2022; 27:4642. [PMID: 35889515 PMCID: PMC9319688 DOI: 10.3390/molecules27144642] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Revised: 07/19/2022] [Accepted: 07/20/2022] [Indexed: 02/06/2023] Open
Abstract
The β3 subunit of nicotinic acetylcholine receptors (nAChRs) participates in heteropentameric assemblies with some α and other β neuronal subunits forming a plethora of various subtypes, differing in their electrophysiological and pharmacological properties. While β3 has for several years been considered an accessory subunit without direct participation in the formation of functional binding sites, recent electrophysiology data have disputed this notion and indicated the presence of a functional (+) side on the extracellular domain (ECD) of β3. In this study, we present the 2.4 Å resolution crystal structure of the monomeric β3 ECD, which revealed rather distinctive loop C features as compared to those of α nAChR subunits, leading to intramolecular stereochemical hindrance of the binding site cavity. Vigorous molecular dynamics simulations in the context of full length pentameric β3-containing nAChRs, while not excluding the possibility of a β3 (+) binding site, demonstrate that this site cannot efficiently accommodate the agonist nicotine. From the structural perspective, our results endorse the accessory rather than functional role of the β3 nAChR subunit, in accordance with earlier functional studies on β3-containing nAChRs.
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Wei K, Louis H, Emori W, Idante PS, Agwamba EC, Cheng CR, Eno EA, Unimuke TO. Antispasmodic activity of carnosic acid extracted from rosmarinus officinalis: Isolation, spectroscopic characterization, DFT studies, and in silico molecular docking investigations. J Mol Struct 2022. [DOI: 10.1016/j.molstruc.2022.132795] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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Elgoyhen AB. The α9α10 nicotinic acetylcholine receptor: a compelling drug target for hearing loss? Expert Opin Ther Targets 2022; 26:291-302. [PMID: 35225139 PMCID: PMC9007918 DOI: 10.1080/14728222.2022.2047931] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
INTRODUCTION Hearing loss is a major health problem, impacting education, communication, interpersonal relationships, and mental health. Drugs that prevent or restore hearing are lacking and hence novel drug targets are sought. There is the possibility of targeting the α9α10 nicotinic acetylcholine receptor (nAChR) in the prevention of noise-induced, hidden hearing loss and presbycusis. This receptor mediates synaptic transmission between medial olivocochlear efferent fibers and cochlear outer hair cells. This target is key since enhanced olivocochlear activity prevents noise-induced hearing loss and delays presbycusis. AREAS COVERED The work examines the α9α10 nicotinic acetylcholine receptor (nAChR), its role in noise-induced, hidden hearing loss and presbycusis and the possibility of targeting. Data has been searched in Pubmed, the World Report on Hearing from the World Health Organization and the Global Burden of Disease Study 2019. EXPERT OPINION The design of positive allosteric modulators of α9α10 nAChRs is proposed because of the advantage of reinforcing the medial olivocochlear (MOC)-hair cell endogenous neurotransmission without directly stimulating the target receptors, therefore avoiding receptor desensitization and reduced efficacy. The time is right for the discovery and development of α9α10 nAChRs targeting agents and high throughput screening assays will support this.
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Affiliation(s)
- Ana Belén Elgoyhen
- Laboratorio de Fisiología y Genética de la Audición, Instituto de Investigaciones en Ingeniería Genética y Biología Molecular "Dr. Héctor N. Torres" (INGEBI), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
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Abstract
Neuronal nicotinic acetylcholine receptors containing the α9 or the α9 and α10 subunits are expressed in various extra-neuronal tissues. Moreover, most cancer cells and tissues highly express α9-containing receptors, and a number of studies have shown that they are powerful regulators of responses that stimulate cancer processes such as proliferation, inhibition of apoptosis, and metastasis. It has also emerged that their modulation is a promising target for drug development. The aim of this review is to summarize recent data showing the involvement of these receptors in controlling the downstream signaling cascades involved in the promotion of cancer.
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Affiliation(s)
- Susanna Pucci
- Institute of Neuroscience, National Research Council (CNR), Milan, Italy
- NeuroMi Milan Center for Neuroscience, University of Milano Bicocca, Milan, Italy
| | - Michele Zoli
- Department of Biomedical, Metabolic and Neural Sciences, Center for Neuroscience and Neurotechnology (CfNN), University of Modena and Reggio Emilia, Modena, Italy
| | - Francesco Clementi
- Institute of Neuroscience, National Research Council (CNR), Milan, Italy
- Department of Medical Biotechnology and Translational Medicine, Università degli Studi di Milano, Milan, Italy
| | - Cecilia Gotti
- Institute of Neuroscience, National Research Council (CNR), Milan, Italy
- NeuroMi Milan Center for Neuroscience, University of Milano Bicocca, Milan, Italy
- *Correspondence: Cecilia Gotti
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13
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Tsetlin V, Haufe Y, Safronova V, Serov D, Shadamarshan P, Son L, Shelukhina I, Kudryavtsev D, Kryukova E, Kasheverov I, Nicke A, Utkin Y. Interaction of α9α10 Nicotinic Receptors With Peptides and Proteins From Animal Venoms. Front Cell Neurosci 2022; 15:765541. [PMID: 35002625 PMCID: PMC8732759 DOI: 10.3389/fncel.2021.765541] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2021] [Accepted: 11/15/2021] [Indexed: 12/13/2022] Open
Abstract
Unlike most neuronal nicotinic acetylcholine receptor (nAChR) subunits, α7, α9, and α10 subunits are able to form functional homo- or heteromeric receptors without any β subunits. While the α7 subtype is widely distributed in the mammalian brain and several peripheral tissues, α9 and α9α10 nAChRs are mainly found in the cochlea and immune cells. α-Conotoxins that specifically block the α9α10 receptor showed anti-nociceptive and anti-hyperalgesic effects in animal models. Hence, this subtype is considered a drug target for analgesics. In contrast to the α9α10-selective α-conotoxins, the three-finger toxin α-bungarotoxin inhibits muscle-type and α7 nAChRs in addition to α9α10 nAChRs. However, the selectivity of α-neurotoxins at the α9α10 subtype was less intensively investigated. Here, we compared the potencies of α-conotoxins and α-neurotoxins at the human α9α10 nAChR by two-electrode voltage clamp analysis upon expression in Xenopus oocytes. In addition, we analyzed effects of several α9α10-selective α-conotoxins on mouse granulocytes from bone marrow to identify possible physiological functions of the α9α10 nAChR subtype in these cells. The α-conotoxin-induced IL-10 release was measured upon LPS-stimulation. We found that α-conotoxins RgIA, PeIA, and Vc1.1 enhance the IL-10 expression in granulocytes which might explain the known anti-inflammatory and associated analgesic activities of α9α10-selective α-conotoxins. Furthermore, we show that two long-chain α-neurotoxins from the cobra Naja melanoleuca venom that were earlier shown to bind to muscle-type and α7 nAChRs, also inhibit the α9α10 subtype at nanomolar concentrations with one of them showing a significantly slower dissociation from this receptor than α-bungarotoxin.
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Affiliation(s)
- Victor Tsetlin
- Department of Molecular Neuroimmune Signaling, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Yves Haufe
- Faculty of Medicine, Walther Straub Institute of Pharmacology and Toxicology, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Valentina Safronova
- Laboratory of Cellular Neurobiology, Institute of Cell Biophysics, Russian Academy of Sciences, Pushchino, Russia
| | - Dmitriy Serov
- Laboratory of Cellular Neurobiology, Institute of Cell Biophysics, Russian Academy of Sciences, Pushchino, Russia
| | - PranavKumar Shadamarshan
- Faculty of Medicine, Walther Straub Institute of Pharmacology and Toxicology, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Lina Son
- Department of Molecular Neuroimmune Signaling, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Irina Shelukhina
- Department of Molecular Neuroimmune Signaling, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Denis Kudryavtsev
- Department of Molecular Neuroimmune Signaling, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Elena Kryukova
- Department of Molecular Neuroimmune Signaling, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Igor Kasheverov
- Department of Molecular Neuroimmune Signaling, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Annette Nicke
- Faculty of Medicine, Walther Straub Institute of Pharmacology and Toxicology, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Yuri Utkin
- Department of Molecular Neuroimmune Signaling, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
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14
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Rosenthal JS, Yuan Q. Constructing and Tuning Excitatory Cholinergic Synapses: The Multifaceted Functions of Nicotinic Acetylcholine Receptors in Drosophila Neural Development and Physiology. Front Cell Neurosci 2021; 15:720560. [PMID: 34650404 PMCID: PMC8505678 DOI: 10.3389/fncel.2021.720560] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Accepted: 08/20/2021] [Indexed: 11/13/2022] Open
Abstract
Nicotinic acetylcholine receptors (nAchRs) are widely distributed within the nervous system across most animal species. Besides their well-established roles in mammalian neuromuscular junctions, studies using invertebrate models have also proven fruitful in revealing the function of nAchRs in the central nervous system. During the earlier years, both in vitro and animal studies had helped clarify the basic molecular features of the members of the Drosophila nAchR gene family and illustrated their utility as targets for insecticides. Later, increasingly sophisticated techniques have illuminated how nAchRs mediate excitatory neurotransmission in the Drosophila brain and play an integral part in neural development and synaptic plasticity, as well as cognitive processes such as learning and memory. This review is intended to provide an updated survey of Drosophila nAchR subunits, focusing on their molecular diversity and unique contributions to physiology and plasticity of the fly neural circuitry. We will also highlight promising new avenues for nAchR research that will likely contribute to better understanding of central cholinergic neurotransmission in both Drosophila and other organisms.
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Affiliation(s)
- Justin S Rosenthal
- National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, United States
| | - Quan Yuan
- National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, United States
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15
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Howard RJ. 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: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [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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16
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Bekbossynova A, Zharylgap A, Filchakova O. Venom-Derived Neurotoxins Targeting Nicotinic Acetylcholine Receptors. Molecules 2021; 26:molecules26113373. [PMID: 34204855 PMCID: PMC8199771 DOI: 10.3390/molecules26113373] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 05/05/2021] [Accepted: 05/07/2021] [Indexed: 01/02/2023] Open
Abstract
Acetylcholine was the first neurotransmitter described. The receptors targeted by acetylcholine are found within organisms spanning different phyla and position themselves as very attractive targets for predation, as well as for defense. Venoms of snakes within the Elapidae family, as well as those of marine snails within the Conus genus, are particularly rich in proteins and peptides that target nicotinic acetylcholine receptors (nAChRs). Such compounds are invaluable tools for research seeking to understand the structure and function of the cholinergic system. Proteins and peptides of venomous origin targeting nAChR demonstrate high affinity and good selectivity. This review aims at providing an overview of the toxins targeting nAChRs found within venoms of different animals, as well as their activities and the structural determinants important for receptor binding.
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Zeng Z, Kociok‐Köhn G, Woodman TJ, Rowan MG, Blagbrough IS. Structural Studies of Norditerpenoid Alkaloids: Conformation Analysis in Crystal and in Solution States. European J Org Chem 2021. [DOI: 10.1002/ejoc.202100179] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Ziyu Zeng
- Department of Pharmacy and Pharmacology University of Bath Bath BA2 7AY UK
| | - Gabriele Kociok‐Köhn
- Material and Chemical Characterisation Facility University of Bath Bath BA2 7AY UK
| | - Timothy J. Woodman
- Department of Pharmacy and Pharmacology University of Bath Bath BA2 7AY UK
| | - Michael G. Rowan
- Department of Pharmacy and Pharmacology University of Bath Bath BA2 7AY UK
| | - Ian S. Blagbrough
- Department of Pharmacy and Pharmacology University of Bath Bath BA2 7AY UK
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18
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Moglie MJ, Marcovich I, Corradi J, Carpaneto Freixas AE, Gallino S, Plazas PV, Bouzat C, Lipovsek M, Elgoyhen AB. Loss of Choline Agonism in the Inner Ear Hair Cell Nicotinic Acetylcholine Receptor Linked to the α10 Subunit. Front Mol Neurosci 2021; 14:639720. [PMID: 33613194 PMCID: PMC7892445 DOI: 10.3389/fnmol.2021.639720] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Accepted: 01/11/2021] [Indexed: 11/13/2022] Open
Abstract
The α9α10 nicotinic acetylcholine receptor (nAChR) plays a fundamental role in inner ear physiology. It mediates synaptic transmission between efferent olivocochlear fibers that descend from the brainstem and hair cells of the auditory sensory epithelium. The α9 and α10 subunits have undergone a distinct evolutionary history within the family of nAChRs. Predominantly in mammalian vertebrates, the α9α10 receptor has accumulated changes at the protein level that may ultimately relate to the evolutionary history of the mammalian hearing organ. In the present work, we investigated the responses of α9α10 nAChRs to choline, the metabolite of acetylcholine degradation at the synaptic cleft. Whereas choline is a full agonist of chicken α9α10 receptors it is a partial agonist of the rat receptor. Making use of the expression of α9α10 heterologous receptors, encompassing wild-type, heteromeric, homomeric, mutant, chimeric, and hybrid receptors, and in silico molecular docking, we establish that the mammalian (rat) α10 nAChR subunit underscores the reduced efficacy of choline. Moreover, we show that whereas the complementary face of the α10 subunit does not play an important role in the activation of the receptor by ACh, it is strictly required for choline responses. Thus, we propose that the evolutionary changes acquired in the mammalian α9α10 nAChR resulted in the loss of choline acting as a full agonist at the efferent synapse, without affecting the triggering of ACh responses. This may have accompanied the fine-tuning of hair cell post-synaptic responses to the high-frequency activity of efferent medial olivocochlear fibers that modulate the cochlear amplifier.
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Affiliation(s)
- Marcelo J. Moglie
- Instituto de Investigaciones en Ingeniería Genética y Biología Molecular “Dr. Héctor N. Torres” (INGEBI), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
| | - Irina Marcovich
- Instituto de Investigaciones en Ingeniería Genética y Biología Molecular “Dr. Héctor N. Torres” (INGEBI), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
| | - Jeremías Corradi
- Departamento de Biología, Bioquímica y Farmacia, Instituto de Investigaciones Bioquímicas de Bahía Blanca (INIBIBB), Universidad Nacional del Sur y Consejo Nacional de Investigaciones Científicas y Técnicas, Buenos Aires, Argentina
| | - Agustín E. Carpaneto Freixas
- Instituto de Investigaciones en Ingeniería Genética y Biología Molecular “Dr. Héctor N. Torres” (INGEBI), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
| | - Sofía Gallino
- Instituto de Investigaciones en Ingeniería Genética y Biología Molecular “Dr. Héctor N. Torres” (INGEBI), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
| | - Paola V. Plazas
- Instituto de Farmacología, Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Cecilia Bouzat
- Departamento de Biología, Bioquímica y Farmacia, Instituto de Investigaciones Bioquímicas de Bahía Blanca (INIBIBB), Universidad Nacional del Sur y Consejo Nacional de Investigaciones Científicas y Técnicas, Buenos Aires, Argentina
| | - Marcela Lipovsek
- Instituto de Investigaciones en Ingeniería Genética y Biología Molecular “Dr. Héctor N. Torres” (INGEBI), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
- Centre for Developmental Neurobiology, King’s College London, Institute of Psychiatry, Psychology, and Neuroscience, Guy’s Campus, London, United Kingdom
| | - Ana Belén Elgoyhen
- Instituto de Investigaciones en Ingeniería Genética y Biología Molecular “Dr. Héctor N. Torres” (INGEBI), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
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19
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Reddy KKA, Jayashree M, Govindu PCV, Gowd KH. Ligand-induced transition in conformations of vicinal cysteine disulfides in proteins. Proteins 2020; 89:599-613. [PMID: 33378101 DOI: 10.1002/prot.26039] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Revised: 11/04/2020] [Accepted: 12/12/2020] [Indexed: 01/02/2023]
Abstract
Vicinal cysteine disulfides are thought to be associated with specific conformations of cysteine disulfides due to the restricted rotation of single bonds in an eight-membered cyclic disulfide loop. Conformations of vicinal cysteine disulfides are analyzed using χ1 , χ2 , χ3 , χ2 ', χ1 ' torsion angles in the crystal structures of proteins retrieved from Protein Data Bank (PDB). 85% of vicinal disulfides have (+, -)LHStaple conformation with trans configuration of the peptide bond and 9% have (-, -)RHStaple conformation with cis configured peptide bond. Conformational analysis of dipeptide Cys-Cys vicinal disulfide by density functional theory (DFT) further supported (+, -)LHStaple, (-, -)RHStaple, and (+, +)RHStaple as the preferred conformations of vicinal disulfides. Interestingly, the rare conformations of vicinal disulfides are observed in the ligand-bound forms of proteins and have higher disulfide strain energy. Conformations of vicinal disulfides in palmitoyl protein thioesterase 1, AChBP, and α7 nicotinic receptor are changed from preferred (+, -)LHStaple to rare (+, -)AntiLHHook/(+, -)AntiRHHook/(+, +)RHStaple conformation due to binding of ligands. Surprisingly, ligands are proximal to the vicinal disulfides in protein complexes that exhibited rare conformations of vicinal disulfides. The report has identified (+, -) LHStaple/(-, -) RHStaple as the hallmark conformations of vicinal disulfides and unraveled ligand-induced transition in conformations of vicinal cysteine disulfides in proteins.
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Affiliation(s)
- K Kasi Amarnath Reddy
- Department of Chemistry, School of Chemical Sciences, Central University of Karnataka, Kalaburagi, India
| | - Muddagoni Jayashree
- Department of Chemistry, School of Chemical Sciences, Central University of Karnataka, Kalaburagi, India
| | - Panchada Ch V Govindu
- Department of Chemistry, School of Chemical Sciences, Central University of Karnataka, Kalaburagi, India
| | - Konkallu Hanumae Gowd
- Department of Chemistry, School of Chemical Sciences, Central University of Karnataka, Kalaburagi, India
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20
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Mineev KS, Kryukova EV, Kasheverov IE, Egorova NS, Zhmak MN, Ivanov IA, Senko DA, Feofanov AV, Ignatova AA, Arseniev AS, Utkin YN, Tsetlin VI. Spatial Structure and Activity of Synthetic Fragments of Lynx1 and of Nicotinic Receptor Loop C Models. Biomolecules 2020; 11:biom11010001. [PMID: 33374963 PMCID: PMC7821949 DOI: 10.3390/biom11010001] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2020] [Revised: 12/06/2020] [Accepted: 12/19/2020] [Indexed: 11/16/2022] Open
Abstract
Lynx1, membrane-bound protein co-localized with the nicotinic acetylcholine receptors (nAChRs) and regulates their function, is a three-finger protein (TFP) made of three β-structural loops, similarly to snake venom α-neurotoxin TFPs. Since the central loop II of α-neurotoxins is involved in binding to nAChRs, we have recently synthesized the fragments of Lynx1 central loop, including those with the disulfide between Cys residues introduced at N- and C-termini, some of them inhibiting muscle-type nAChR similarly to the whole-size water-soluble Lynx1 (ws-Lynx1). Literature shows that the main fragment interacting with TFPs is the C-loop of both nAChRs and acetylcholine binding proteins (AChBPs) while some ligand-binding capacity is preserved by analogs of this loop, for example, by high-affinity peptide HAP. Here we analyzed the structural organization of these peptide models of ligands and receptors and its role in binding. Thus, fragments of Lynx1 loop II, loop C from the Lymnaea stagnalis AChBP and HAP were synthesized in linear and Cys-cyclized forms and structurally (CD and NMR) and functionally (radioligand assay on Torpedo nAChR) characterized. Connecting the C- and N-termini by disulfide in the ws-Lynx1 fragment stabilized its conformation which became similar to the loop II within the 1H-NMR structure of ws-Lynx1, the activity being higher than for starting linear fragment but lower than for peptide with free cysteines. Introduced disulfides did not considerably change the structure of HAP and of loop C fragments, the former preserving high affinity for α-bungarotoxin, while, surprisingly, no binding was detected with loop C and its analogs.
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Affiliation(s)
- Konstantin S. Mineev
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 117997 Moscow, Russia; (E.V.K.); (I.E.K.); (N.S.E.); (M.N.Z.); (I.A.I.); (D.A.S.); (A.V.F.); (A.A.I.); (A.S.A.); (Y.N.U.); (V.I.T.)
- Department of Physico-Chemical Biology and Biotechnology, Moscow Institute of Physics and Technology, 141700 Dolgoprudnyi, Russia
- Correspondence: ; Tel.: +7-(495)-330-74-83
| | - Elena V. Kryukova
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 117997 Moscow, Russia; (E.V.K.); (I.E.K.); (N.S.E.); (M.N.Z.); (I.A.I.); (D.A.S.); (A.V.F.); (A.A.I.); (A.S.A.); (Y.N.U.); (V.I.T.)
| | - Igor E. Kasheverov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 117997 Moscow, Russia; (E.V.K.); (I.E.K.); (N.S.E.); (M.N.Z.); (I.A.I.); (D.A.S.); (A.V.F.); (A.A.I.); (A.S.A.); (Y.N.U.); (V.I.T.)
- Laboratory of Molecular Biology and Biochemistry, Institute of Molecular Medicine, Biomedical Science and Technology Park, Sechenov First Moscow State Medical University, 119991 Moscow, Russia
| | - Natalia S. Egorova
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 117997 Moscow, Russia; (E.V.K.); (I.E.K.); (N.S.E.); (M.N.Z.); (I.A.I.); (D.A.S.); (A.V.F.); (A.A.I.); (A.S.A.); (Y.N.U.); (V.I.T.)
| | - Maxim N. Zhmak
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 117997 Moscow, Russia; (E.V.K.); (I.E.K.); (N.S.E.); (M.N.Z.); (I.A.I.); (D.A.S.); (A.V.F.); (A.A.I.); (A.S.A.); (Y.N.U.); (V.I.T.)
| | - Igor A. Ivanov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 117997 Moscow, Russia; (E.V.K.); (I.E.K.); (N.S.E.); (M.N.Z.); (I.A.I.); (D.A.S.); (A.V.F.); (A.A.I.); (A.S.A.); (Y.N.U.); (V.I.T.)
| | - Dmitry A. Senko
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 117997 Moscow, Russia; (E.V.K.); (I.E.K.); (N.S.E.); (M.N.Z.); (I.A.I.); (D.A.S.); (A.V.F.); (A.A.I.); (A.S.A.); (Y.N.U.); (V.I.T.)
- Department of Chemistry, Lomonosov Moscow State University, 119991 Moscow, Russia
| | - Alexey V. Feofanov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 117997 Moscow, Russia; (E.V.K.); (I.E.K.); (N.S.E.); (M.N.Z.); (I.A.I.); (D.A.S.); (A.V.F.); (A.A.I.); (A.S.A.); (Y.N.U.); (V.I.T.)
- Biological Faculty, Lomonosov Moscow State University, 119991 Moscow, Russia
| | - Anastasia A. Ignatova
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 117997 Moscow, Russia; (E.V.K.); (I.E.K.); (N.S.E.); (M.N.Z.); (I.A.I.); (D.A.S.); (A.V.F.); (A.A.I.); (A.S.A.); (Y.N.U.); (V.I.T.)
| | - Alexander S. Arseniev
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 117997 Moscow, Russia; (E.V.K.); (I.E.K.); (N.S.E.); (M.N.Z.); (I.A.I.); (D.A.S.); (A.V.F.); (A.A.I.); (A.S.A.); (Y.N.U.); (V.I.T.)
| | - Yuri N. Utkin
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 117997 Moscow, Russia; (E.V.K.); (I.E.K.); (N.S.E.); (M.N.Z.); (I.A.I.); (D.A.S.); (A.V.F.); (A.A.I.); (A.S.A.); (Y.N.U.); (V.I.T.)
| | - Victor I. Tsetlin
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 117997 Moscow, Russia; (E.V.K.); (I.E.K.); (N.S.E.); (M.N.Z.); (I.A.I.); (D.A.S.); (A.V.F.); (A.A.I.); (A.S.A.); (Y.N.U.); (V.I.T.)
- Institute for Physics and Engineering in Biomedicine, National Research Nuclear University MEPhI, 115409 Moscow, Russia
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21
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Li X, Tae HS, Chu Y, Jiang T, Adams DJ, Yu R. Medicinal chemistry, pharmacology, and therapeutic potential of α-conotoxins antagonizing the α9α10 nicotinic acetylcholine receptor. Pharmacol Ther 2020; 222:107792. [PMID: 33309557 DOI: 10.1016/j.pharmthera.2020.107792] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Accepted: 12/07/2020] [Indexed: 12/20/2022]
Abstract
α-Conotoxins are disulfide-rich and well-structured peptides, most of which can block nicotinic acetylcholine receptors (nAChRs) with exquisite selectivity and potency. There are various nAChR subtypes, of which the α9α10 nAChR functions as a heteromeric ionotropic receptor in the mammalian cochlea and mediates postsynaptic transmission from the medial olivocochlear. The α9α10 nAChR subtype has also been proposed as a target for the treatment of neuropathic pain and the suppression of breast cancer cell proliferation. Therefore, α-conotoxins targeting the α9α10 nAChR are potentially useful in the development of specific therapeutic drugs and pharmacological tools. Despite dissimilarities in their amino acid sequence and structures, these conopeptides are potent antagonists of the α9α10 nAChR subtype. Consequently, the activity and stability of these peptides have been subjected to chemical modifications. The resulting synthetic analogues have not only functioned as molecular probes to explore ligand binding sites of the α9α10 nAChR, but also have the potential to become candidates for drug development. From the perspectives of medicinal chemistry and pharmacology, we highlight the structure and function of the α9α10 nAChR and review studies of α-conotoxins targeting it, including their three-dimensional structures, structure optimization strategies, and binding modes at the α9α10 nAChR, as well as their therapeutic potential.
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Affiliation(s)
- Xiao Li
- 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
| | - Han-Shen Tae
- Illawarra Health and Medical Research Institute (IHMRI), University of Wollongong, Wollongong, New South Wales 2522, Australia
| | - Yanyan Chu
- 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; Innovation Platform of Marine Drug Screening & Evaluation, Qingdao National Laboratory for Marine Science and Technology, Qingdao, Shandong 266100, 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
| | - David J Adams
- Illawarra Health and Medical Research Institute (IHMRI), University of Wollongong, Wollongong, New South Wales 2522, Australia.
| | - 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; Innovation Platform of Marine Drug Screening & Evaluation, Qingdao National Laboratory for Marine Science and Technology, Qingdao, Shandong 266100, China.
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22
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Ho TNT, Abraham N, Lewis RJ. Structure-Function of Neuronal Nicotinic Acetylcholine Receptor Inhibitors Derived From Natural Toxins. Front Neurosci 2020; 14:609005. [PMID: 33324158 PMCID: PMC7723979 DOI: 10.3389/fnins.2020.609005] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Accepted: 10/30/2020] [Indexed: 12/19/2022] Open
Abstract
Neuronal nicotinic acetylcholine receptors (nAChRs) are prototypical cation-selective, ligand-gated ion channels that mediate fast neurotransmission in the central and peripheral nervous systems. nAChRs are involved in a range of physiological and pathological functions and hence are important therapeutic targets. Their subunit homology and diverse pentameric assembly contribute to their challenging pharmacology and limit their drug development potential. Toxins produced by an extensive range of algae, plants and animals target nAChRs, with many proving pivotal in elucidating receptor pharmacology and biochemistry, as well as providing templates for structure-based drug design. The crystal structures of these toxins with diverse chemical profiles in complex with acetylcholine binding protein (AChBP), a soluble homolog of the extracellular ligand-binding domain of the nAChRs and more recently the extracellular domain of human α9 nAChRs, have been reported. These studies have shed light on the diverse molecular mechanisms of ligand-binding at neuronal nAChR subtypes and uncovered critical insights useful for rational drug design. This review provides a comprehensive overview and perspectives obtained from structure and function studies of diverse plant and animal toxins and their associated inhibitory mechanisms at neuronal nAChRs.
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Affiliation(s)
| | | | - Richard J. Lewis
- Centre for Pain Research, Institute for Molecular Bioscience, The University of Queensland, St Lucia, QLD, Australia
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Gulsevin A, Meiler J. An Investigation of Three-Finger Toxin-nAChR Interactions through Rosetta Protein Docking. Toxins (Basel) 2020; 12:E598. [PMID: 32947868 PMCID: PMC7551183 DOI: 10.3390/toxins12090598] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Revised: 09/11/2020] [Accepted: 09/12/2020] [Indexed: 12/14/2022] Open
Abstract
Three-finger toxins (3FTX) are a group of peptides that affect multiple receptor types. One group of proteins affected by 3FTX are nicotinic acetylcholine receptors (nAChR). Structural information on how neurotoxins interact with nAChR is limited and is confined to a small group of neurotoxins. Therefore, in silico methods are valuable in understanding the interactions between 3FTX and different nAChR subtypes, but there are no established protocols to model 3FTX-nAChR interactions. We followed a homology modeling and protein docking protocol to address this issue and tested its success on three different systems. First, neurotoxin peptides co-crystallized with acetylcholine binding protein (AChBP) were re-docked to assess whether Rosetta protein-protein docking can reproduce the native poses. Second, experimental data on peptide binding to AChBP was used to test whether the docking protocol can qualitatively distinguish AChBP-binders from non-binders. Finally, we docked eight peptides with known α7 and muscle-type nAChR binding properties to test whether the protocol can explain the differential activities of the peptides at the two receptor subtypes. Overall, the docking protocol predicted the qualitative and some specific aspects of 3FTX binding to nAChR with reasonable success and shed light on unknown aspects of 3FTX binding to different receptor subtypes.
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Affiliation(s)
- Alican Gulsevin
- Department of Chemistry, Vanderbilt University, Nashville, TN 37212, USA;
| | - Jens Meiler
- Department of Chemistry, Vanderbilt University, Nashville, TN 37212, USA;
- Institute for Drug Discovery, Leipzig University Medical School, 04103 Leipzig, Germany
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24
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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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25
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Nirthanan S. Snake three-finger α-neurotoxins and nicotinic acetylcholine receptors: molecules, mechanisms and medicine. Biochem Pharmacol 2020; 181:114168. [PMID: 32710970 DOI: 10.1016/j.bcp.2020.114168] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Revised: 07/20/2020] [Accepted: 07/20/2020] [Indexed: 12/13/2022]
Abstract
Snake venom three-finger α-neurotoxins (α-3FNTx) act on postsynaptic nicotinic acetylcholine receptors (nAChRs) at the neuromuscular junction (NMJ) to produce skeletal muscle paralysis. The discovery of the archetypal α-bungarotoxin (α-BgTx), almost six decades ago, exponentially expanded our knowledge of membrane receptors and ion channels. This included the localisation, isolation and characterization of the first receptor (nAChR); and by extension, the pathophysiology and pharmacology of neuromuscular transmission and associated pathologies such as myasthenia gravis, as well as our understanding of the role of α-3FNTxs in snakebite envenomation leading to novel concepts of targeted treatment. Subsequent studies on a variety of animal venoms have yielded a plethora of novel toxins that have revolutionized molecular biomedicine and advanced drug discovery from bench to bedside. This review provides an overview of nAChRs and their subtypes, classification of α-3FNTxs and the challenges of typifying an increasing arsenal of structurally and functionally unique toxins, and the three-finger protein (3FP) fold in the context of the uPAR/Ly6/CD59/snake toxin superfamily. The pharmacology of snake α-3FNTxs including their mechanisms of neuromuscular blockade, variations in reversibility of nAChR interactions, specificity for nAChR subtypes or for distinct ligand-binding interfaces within a subtype and the role of α-3FNTxs in neurotoxic envenomation are also detailed. Lastly, a reconciliation of structure-function relationships between α-3FNTx and nAChRs, derived from historical mutational and biochemical studies and emerging atomic level structures of nAChR models in complex with α-3FNTxs is discussed.
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Affiliation(s)
- Selvanayagam Nirthanan
- School of Medical Science, Griffith Health Group, Griffith University, Gold Coast, Queensland, Australia.
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26
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Tsetlin VI, Kasheverov IE, Utkin YN. Three-finger proteins from snakes and humans acting on nicotinic receptors: Old and new. J Neurochem 2020; 158:1223-1235. [PMID: 32648941 DOI: 10.1111/jnc.15123] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2020] [Revised: 06/25/2020] [Accepted: 07/06/2020] [Indexed: 12/12/2022]
Abstract
The first toxin to give rise to the three-finger protein (TFP) family was α-bungarotoxin (α-Bgt) from Bungarus multicinctus krait venom. α-Bgt was crucial for research on nicotinic acetylcholine receptors (nAChRs), and in this Review article we focus on present data for snake venom TFPs and those of the Ly6/uPAR family from mammalians (membrane-bound Lynx1 and secreted SLURP-1) interacting with nAChRs. Recently isolated from Bungarus candidus venom, αδ-bungarotoxins differ from α-Bgt: they bind more reversibly and distinguish two binding sites in Torpedo californica nAChR. Naja kaouthia α-cobratoxin, classical blocker of nAChRs, was shown to inhibit certain GABA-A receptor subtypes, whereas α-cobratoxin dimer with 2 intermolecular disulfides has a novel type of 3D structure. Non-conventional toxin WTX has additional 5th disulfide not in the central loop, as α-Bgt, but in the N-terminal loop, like all Ly6/uPAR proteins, and inhibits α7 and Torpedo nAChRs. A water-soluble form of Lynx1, ws-Lynx1, was expressed in E. coli, its 1 H-NMR structure and binding to several nAChRs determined. For SLURP-1, similar information was obtained with its recombinant analogue rSLURP-1. A common feature of ws-Lynx1, rSLURP-1, and WTX is their activity against nAChRs and muscarinic acetylcholine receptors. Synthetic SLURP-1, identical to the natural protein, demonstrated some differences from rSLURP-1 in distinguishing nAChR subtypes. The loop II fragment of the Lynx1 was synthesized having the same µM affinity for the Torpedo nAChR as ws-Lynx1. This review illustrates the productivity of parallel research of nAChR interactions with the two TFP groups.
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Affiliation(s)
- Victor I Tsetlin
- Department of Molecular Neuroimmune Signalling, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russian Federation.,PhysBio of MePhi, Moscow, Russian Federation
| | - Igor E Kasheverov
- Department of Molecular Neuroimmune Signalling, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russian Federation.,Sechenov First Moscow State Medical University, Institute of Molecular Medicine, Moscow, Russian Federation
| | - Yuri N Utkin
- Department of Molecular Neuroimmune Signalling, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russian Federation
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27
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Xing H, Andrud KW, Soti F, Rouchaud A, Jahn SC, Lu Z, Cho YH, Habibi S, Corsino P, Slavov S, Rocca JR, Lindstrom JM, Lukas RJ, Kem WR. A Methyl Scan of the Pyrrolidinium Ring of Nicotine Reveals Significant Differences in Its Interactions with α7 and α4 β2 Nicotinic Acetylcholine Receptors. Mol Pharmacol 2020; 98:168-180. [PMID: 32474444 DOI: 10.1124/mol.119.118786] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2019] [Accepted: 05/06/2020] [Indexed: 01/15/2023] Open
Abstract
The two major nicotinic acetylcholine receptors (nAChRs) in the brain are the α4β2 and α7 subtypes. A "methyl scan" of the pyrrolidinium ring was used to detect differences in nicotine's interactions with these two receptors. Each methylnicotine was investigated using voltage-clamp and radioligand binding techniques. Methylation at each ring carbon elicited unique changes in nicotine's receptor interactions. Replacing the 1'-N-methyl with an ethyl group or adding a second 1'-N-methyl group significantly reduced interaction with α4β2 but not α7 receptors. The 2'-methylation uniquely enhanced binding and agonist potency at α7 receptors. Although 3'- and 5'-trans-methylations were much better tolerated by α7 receptors than α4β2 receptors, 4'-methylation decreased potency and efficacy at α7 receptors much more than at α4β2 receptors. Whereas cis-5'-methylnicotine lacked agonist activity and displayed a low affinity at both receptors, trans-5'-methylnicotine retained considerable α7 receptor activity. Differences between the two 5'-methylated analogs of the potent pyridyl oxymethylene-bridged nicotine analog A84543 were consistent with what was found for the 5'-methylnicotines. Computer docking of the methylnicotines to the Lymnaea acetylcholine binding protein crystal structure containing two persistent waters predicted most of the changes in receptor affinity that were observed with methylation, particularly the lower affinities of the cis-methylnicotines. The much smaller effects of 1'-, 3'-, and 5'-methylations and the greater effects of 2'- and 4'-methylations on nicotine α7 nAChR interaction might be exploited for the design of new drugs based on the nicotine scaffold. SIGNIFICANCE STATEMENT: Using a comprehensive "methyl scan" approach, we show that the orthosteric binding sites for acetylcholine and nicotine in the two major brain nicotinic acetylcholine receptors interact differently with the pyrrolidinium ring of nicotine, and we suggest reasons for the higher affinity of nicotine for the heteromeric receptor. Potential sites for nicotine structure modification were identified that may be useful in the design of new drugs targeting these receptors.
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Affiliation(s)
- Hong Xing
- Department of Pharmacology and Therapeutics (H.X., K.W.A., F.S., A.R., S.C.J., Z.L., Y.-H.C., S.H., P.C., W.R.K.) and AMRIS, McKnight Brain Institute (J.R.R.), College of Medicine, University of Florida, Gainesville, Florida; National Center for Toxicological Research, US Food and Drug Administration, Jefferson, Arkansas (S.S.); Department of Neuroscience, University of Pennsylvania, Philadelphia, Pennsylvania (J.M.L.); and Division of Neurobiology, Barrow Neurologic Institute, Phoenix, Arizona (R.J.L.)
| | - Kristin W Andrud
- Department of Pharmacology and Therapeutics (H.X., K.W.A., F.S., A.R., S.C.J., Z.L., Y.-H.C., S.H., P.C., W.R.K.) and AMRIS, McKnight Brain Institute (J.R.R.), College of Medicine, University of Florida, Gainesville, Florida; National Center for Toxicological Research, US Food and Drug Administration, Jefferson, Arkansas (S.S.); Department of Neuroscience, University of Pennsylvania, Philadelphia, Pennsylvania (J.M.L.); and Division of Neurobiology, Barrow Neurologic Institute, Phoenix, Arizona (R.J.L.)
| | - Ferenc Soti
- Department of Pharmacology and Therapeutics (H.X., K.W.A., F.S., A.R., S.C.J., Z.L., Y.-H.C., S.H., P.C., W.R.K.) and AMRIS, McKnight Brain Institute (J.R.R.), College of Medicine, University of Florida, Gainesville, Florida; National Center for Toxicological Research, US Food and Drug Administration, Jefferson, Arkansas (S.S.); Department of Neuroscience, University of Pennsylvania, Philadelphia, Pennsylvania (J.M.L.); and Division of Neurobiology, Barrow Neurologic Institute, Phoenix, Arizona (R.J.L.)
| | - Anne Rouchaud
- Department of Pharmacology and Therapeutics (H.X., K.W.A., F.S., A.R., S.C.J., Z.L., Y.-H.C., S.H., P.C., W.R.K.) and AMRIS, McKnight Brain Institute (J.R.R.), College of Medicine, University of Florida, Gainesville, Florida; National Center for Toxicological Research, US Food and Drug Administration, Jefferson, Arkansas (S.S.); Department of Neuroscience, University of Pennsylvania, Philadelphia, Pennsylvania (J.M.L.); and Division of Neurobiology, Barrow Neurologic Institute, Phoenix, Arizona (R.J.L.)
| | - Stephan C Jahn
- Department of Pharmacology and Therapeutics (H.X., K.W.A., F.S., A.R., S.C.J., Z.L., Y.-H.C., S.H., P.C., W.R.K.) and AMRIS, McKnight Brain Institute (J.R.R.), College of Medicine, University of Florida, Gainesville, Florida; National Center for Toxicological Research, US Food and Drug Administration, Jefferson, Arkansas (S.S.); Department of Neuroscience, University of Pennsylvania, Philadelphia, Pennsylvania (J.M.L.); and Division of Neurobiology, Barrow Neurologic Institute, Phoenix, Arizona (R.J.L.)
| | - Ziang Lu
- Department of Pharmacology and Therapeutics (H.X., K.W.A., F.S., A.R., S.C.J., Z.L., Y.-H.C., S.H., P.C., W.R.K.) and AMRIS, McKnight Brain Institute (J.R.R.), College of Medicine, University of Florida, Gainesville, Florida; National Center for Toxicological Research, US Food and Drug Administration, Jefferson, Arkansas (S.S.); Department of Neuroscience, University of Pennsylvania, Philadelphia, Pennsylvania (J.M.L.); and Division of Neurobiology, Barrow Neurologic Institute, Phoenix, Arizona (R.J.L.)
| | - Yeh-Hyon Cho
- Department of Pharmacology and Therapeutics (H.X., K.W.A., F.S., A.R., S.C.J., Z.L., Y.-H.C., S.H., P.C., W.R.K.) and AMRIS, McKnight Brain Institute (J.R.R.), College of Medicine, University of Florida, Gainesville, Florida; National Center for Toxicological Research, US Food and Drug Administration, Jefferson, Arkansas (S.S.); Department of Neuroscience, University of Pennsylvania, Philadelphia, Pennsylvania (J.M.L.); and Division of Neurobiology, Barrow Neurologic Institute, Phoenix, Arizona (R.J.L.)
| | - Sophia Habibi
- Department of Pharmacology and Therapeutics (H.X., K.W.A., F.S., A.R., S.C.J., Z.L., Y.-H.C., S.H., P.C., W.R.K.) and AMRIS, McKnight Brain Institute (J.R.R.), College of Medicine, University of Florida, Gainesville, Florida; National Center for Toxicological Research, US Food and Drug Administration, Jefferson, Arkansas (S.S.); Department of Neuroscience, University of Pennsylvania, Philadelphia, Pennsylvania (J.M.L.); and Division of Neurobiology, Barrow Neurologic Institute, Phoenix, Arizona (R.J.L.)
| | - Patrick Corsino
- Department of Pharmacology and Therapeutics (H.X., K.W.A., F.S., A.R., S.C.J., Z.L., Y.-H.C., S.H., P.C., W.R.K.) and AMRIS, McKnight Brain Institute (J.R.R.), College of Medicine, University of Florida, Gainesville, Florida; National Center for Toxicological Research, US Food and Drug Administration, Jefferson, Arkansas (S.S.); Department of Neuroscience, University of Pennsylvania, Philadelphia, Pennsylvania (J.M.L.); and Division of Neurobiology, Barrow Neurologic Institute, Phoenix, Arizona (R.J.L.)
| | - Svetoslav Slavov
- Department of Pharmacology and Therapeutics (H.X., K.W.A., F.S., A.R., S.C.J., Z.L., Y.-H.C., S.H., P.C., W.R.K.) and AMRIS, McKnight Brain Institute (J.R.R.), College of Medicine, University of Florida, Gainesville, Florida; National Center for Toxicological Research, US Food and Drug Administration, Jefferson, Arkansas (S.S.); Department of Neuroscience, University of Pennsylvania, Philadelphia, Pennsylvania (J.M.L.); and Division of Neurobiology, Barrow Neurologic Institute, Phoenix, Arizona (R.J.L.)
| | - James R Rocca
- Department of Pharmacology and Therapeutics (H.X., K.W.A., F.S., A.R., S.C.J., Z.L., Y.-H.C., S.H., P.C., W.R.K.) and AMRIS, McKnight Brain Institute (J.R.R.), College of Medicine, University of Florida, Gainesville, Florida; National Center for Toxicological Research, US Food and Drug Administration, Jefferson, Arkansas (S.S.); Department of Neuroscience, University of Pennsylvania, Philadelphia, Pennsylvania (J.M.L.); and Division of Neurobiology, Barrow Neurologic Institute, Phoenix, Arizona (R.J.L.)
| | - Jon M Lindstrom
- Department of Pharmacology and Therapeutics (H.X., K.W.A., F.S., A.R., S.C.J., Z.L., Y.-H.C., S.H., P.C., W.R.K.) and AMRIS, McKnight Brain Institute (J.R.R.), College of Medicine, University of Florida, Gainesville, Florida; National Center for Toxicological Research, US Food and Drug Administration, Jefferson, Arkansas (S.S.); Department of Neuroscience, University of Pennsylvania, Philadelphia, Pennsylvania (J.M.L.); and Division of Neurobiology, Barrow Neurologic Institute, Phoenix, Arizona (R.J.L.)
| | - Ron J Lukas
- Department of Pharmacology and Therapeutics (H.X., K.W.A., F.S., A.R., S.C.J., Z.L., Y.-H.C., S.H., P.C., W.R.K.) and AMRIS, McKnight Brain Institute (J.R.R.), College of Medicine, University of Florida, Gainesville, Florida; National Center for Toxicological Research, US Food and Drug Administration, Jefferson, Arkansas (S.S.); Department of Neuroscience, University of Pennsylvania, Philadelphia, Pennsylvania (J.M.L.); and Division of Neurobiology, Barrow Neurologic Institute, Phoenix, Arizona (R.J.L.)
| | - William R Kem
- Department of Pharmacology and Therapeutics (H.X., K.W.A., F.S., A.R., S.C.J., Z.L., Y.-H.C., S.H., P.C., W.R.K.) and AMRIS, McKnight Brain Institute (J.R.R.), College of Medicine, University of Florida, Gainesville, Florida; National Center for Toxicological Research, US Food and Drug Administration, Jefferson, Arkansas (S.S.); Department of Neuroscience, University of Pennsylvania, Philadelphia, Pennsylvania (J.M.L.); and Division of Neurobiology, Barrow Neurologic Institute, Phoenix, Arizona (R.J.L.)
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28
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Rahman MM, Teng J, Worrell BT, Noviello CM, Lee M, Karlin A, Stowell MHB, Hibbs RE. Structure of the Native Muscle-type Nicotinic Receptor and Inhibition by Snake Venom Toxins. Neuron 2020; 106:952-962.e5. [PMID: 32275860 DOI: 10.1016/j.neuron.2020.03.012] [Citation(s) in RCA: 119] [Impact Index Per Article: 29.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Revised: 01/13/2020] [Accepted: 03/15/2020] [Indexed: 12/28/2022]
Abstract
The nicotinic acetylcholine receptor, a pentameric ligand-gated ion channel, converts the free energy of binding of the neurotransmitter acetylcholine into opening of its central pore. Here we present the first high-resolution structure of the receptor type found in muscle-endplate membrane and in the muscle-derived electric tissues of fish. The native receptor was purified from Torpedo electric tissue and functionally reconstituted in lipids optimal for cryo-electron microscopy. The receptor was stabilized in a closed state by the binding of α-bungarotoxin. The structure reveals the binding of a toxin molecule at each of two subunit interfaces in a manner that would block the binding of acetylcholine. It also reveals a closed gate in the ion-conducting pore, formed by hydrophobic amino acid side chains, located ∼60 Å from the toxin binding sites. The structure provides a framework for understanding gating in ligand-gated channels and how mutations in the acetylcholine receptor cause congenital myasthenic syndromes.
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Affiliation(s)
- Md Mahfuzur Rahman
- Department of Neuroscience, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Jinfeng Teng
- Department of Neuroscience, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Brady T Worrell
- Department of Molecular, Cellular & Developmental Biology, University of Colorado, Boulder, CO 80309, USA
| | - Colleen M Noviello
- Department of Neuroscience, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Myeongseon Lee
- Department of Molecular, Cellular & Developmental Biology, University of Colorado, Boulder, CO 80309, USA
| | - Arthur Karlin
- Center for Molecular Recognition & Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY 10032, USA
| | - Michael H B Stowell
- Department of Molecular, Cellular & Developmental Biology, University of Colorado, Boulder, CO 80309, USA.
| | - Ryan E Hibbs
- Department of Neuroscience, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.
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29
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Abstract
Here we begin by briefly reviewing landmark structural studies on the nicotinic acetylcholine receptor. We highlight challenges that had to be overcome to push through resolution barriers, then focus on what has been gleaned in the past few years from crystallographic and single particle cryo-EM studies of different nicotinic receptor subunit assemblies and ligand complexes. We discuss insights into ligand recognition, ion permeation, and allosteric gating. We then highlight some foundational aspects of nicotinic receptor structural biology that remain unresolved and are areas ripe for future exploration. This article is part of the special issue on 'Contemporary Advances in Nicotine Neuropharmacology'.
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30
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Kudryavtsev DS, Tabakmakher VМ, Budylin GS, Egorova NS, Efremov RG, Ivanov IA, Belukhina SY, Jegorov AV, Kasheverov IE, Kryukova EV, Shelukhina IV, Shirshin EA, Zhdanova NG, Zhmak MN, Tsetlin VI. Complex approach for analysis of snake venom α-neurotoxins binding to HAP, the high-affinity peptide. Sci Rep 2020; 10:3861. [PMID: 32123252 DOI: 10.1038/s41598-020-60768-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2019] [Accepted: 02/14/2020] [Indexed: 12/30/2022] Open
Abstract
Snake venom α-neurotoxins, invaluable pharmacological tools, bind with high affinity to distinct subtypes of nicotinic acetylcholine receptor. The combinatorial high-affinity peptide (HAP), homologous to the C-loop of α1 and α7 nAChR subunits, binds biotinylated α-bungarotoxin (αBgt) with nanomolar affinity and might be a protection against snake-bites. Since there are no data on HAP interaction with other toxins, we checked its binding of α-cobratoxin (αCtx), similar to αBgt in action on nAChRs. Using radioiodinated αBgt, we confirmed a high affinity of HAP for αBgt, the complex formation is supported by mass spectrometry and gel chromatography, but only weak binding was registered with αCtx. A combination of protein intrinsic fluorescence measurements with the principal component analysis of the spectra allowed us to measure the HAP-αBgt binding constant directly (29 nM). These methods also confirmed weak HAP interaction with αCtx (>10000 nM). We attempted to enhance it by modification of HAP structure relying on the known structures of α-neurotoxins with various targets and applying molecular dynamics. A series of HAP analogues have been synthesized, HAP[L9E] analogue being considerably more potent than HAP in αCtx binding (7000 nM). The proposed combination of experimental and computational approaches appears promising for analysis of various peptide-protein interactions.
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31
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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: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [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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Rojas-Rodríguez F, Morantes C, Pinzón A, Barreto GE, Cabezas R, Mariño-Ramírez L, González J. Machine Learning Neuroprotective Strategy Reveals a Unique Set of Parkinson Therapeutic Nicotine Analogs. Open Bioinforma J 2020; 13:1-14. [PMID: 33927788 PMCID: PMC8081347] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
AIMS Present a novel machine learning computational strategy to predict the neuroprotection potential of nicotine analogs acting over the behavior of unpaired signaling pathways in Parkinson's disease. BACKGROUND Dopaminergic replacement has been used for Parkinson's Disease (PD) treatment with positive effects on motor symptomatology but low progression and prevention effects. Epidemiological studies have shown that nicotine consumption decreases PD prevalence through neuroprotective mechanisms activation associated with the overstimulation of signaling pathways (SP) such as PI3K/AKT through nicotinic acetylcholine receptors (e.g α7 nAChRs) and over-expression of anti-apoptotic genes such as Bcl-2. Nicotine analogs with similar neuroprotective activity but decreased secondary effects remain as a promissory field. OBJECTIVE The objective of this study is to develop an interdisciplinary computational strategy predicting the neuroprotective activity of a series of 8 novel nicotine analogs over Parkinson's disease. METHODS We present a computational strategy integrating structural bioinformatics, SP manual reconstruction, and deep learning to predict the potential neuroprotective activity of 8 novel nicotine analogs over the behavior of PI3K/AKT. We performed a protein-ligand analysis between nicotine analogs and α7 nAChRs receptor using geometrical conformers, physicochemical characterization of the analogs and developed manually curated neuroprotective datasets to analyze their potential activity. Additionally, we developed a predictive machine-learning model for neuroprotection in PD through the integration of Markov Chain Monte-Carlo transition matrix for the 2 SP with synthetic training datasets of the physicochemical properties and structural dataset. RESULTS Our model was able to predict the potential neuroprotective activity of seven new nicotine analogs based on the binomial Bcl-2 response regulated by the activation of PI3K/AKT. CONCLUSION Hereby, we present a robust novel strategy to assess the neuroprotective potential of biomolecules based on SP architecture. Our theoretical strategy can be further applied to the study of new treatments related to SP deregulation and may ultimately offer new opportunities for therapeutic interventions in neurodegenerative diseases.
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Affiliation(s)
- Felipe Rojas-Rodríguez
- Departamento de Nutrición y Bioquímica, Pontificia Universidad Javeriana. Bogotá D.C, Republic of Colombia,Address correspondence to the author at the Departamento de Nutrición y Bioquímica, Pontificia Universidad Javeriana. Bogotá D.C, Republic of Colombia;
| | - Carlos Morantes
- Departamento de Biología, Universidad Nacional de Colombia. Bogotá, Republic of Colombia
| | - Andrés Pinzón
- Instituto de Genética, Universidad Nacional de Colombia, Bogotá, Republic of Colombia
| | - George E. Barreto
- Department of Biological Sciences, University of Limerick, Limerick, Ireland
| | - Ricardo Cabezas
- Departamento de Nutrición y Bioquímica, Pontificia Universidad Javeriana. Bogotá D.C, Republic of Colombia
| | - Leonardo Mariño-Ramírez
- National Center for Biotechnology Information, National Library of Medicine, National Institute of Health, 8600 Rockville Pike, Bethesda, MD 20894, USA
| | - Janneth González
- Departamento de Nutrición y Bioquímica, Pontificia Universidad Javeriana. Bogotá D.C, Republic of Colombia
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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Chu X, Tae HS, Xu Q, Jiang T, Adams DJ, Yu R. α-Conotoxin Vc1.1 Structure-Activity Relationship at the Human α9α10 Nicotinic Acetylcholine Receptor Investigated by Minimal Side Chain Replacement. ACS Chem Neurosci 2019; 10:4328-4336. [PMID: 31411453 DOI: 10.1021/acschemneuro.9b00389] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
α-Conotoxin Vc1.1 inhibits the nicotinic acetylcholine receptor (nAChR) α9α10 subtype and has the potential to treat neuropathic chronic pain. To date, the crystal structure of Vc1.1-bound α9α10 nAChR remains unavailable; thus, understanding the structure-activity relationship of Vc1.1 with the α9α10 nAChR remains challenging. In this study, the Vc1.1 side chains were minimally modified to avoid introducing large local conformation perturbation to the interactions between Vc1.1 and α9α10 nAChR. The results suggest that the hydroxyl group of Vc1.1, Y10, forms a hydrogen bond with the carbonyl group of α9 N107 and a hydrogen bond donor is required. However, Vc1.1 S4 is adjacent to the α9 D166 and D169, and a positive charge residue at this position increases the binding affinity of Vc1.1. Furthermore, the carboxyl group of Vc1.1, D11, forms two hydrogen bonds with α9 N154 and R81, respectively, whereas introducing an extra carboxyl group at this position significantly decreases the potency of Vc1.1. Second-generation mutants of Vc1.1 [S4 Dab, N9A] and [S4 Dab, N9W] increased potency at the α9α10 nAChR by 20-fold compared with that of Vc1.1. The [S4 Dab, N9W] mutational effects at positions 4 and 9 of Vc1.1 are not cumulative but are coupled with each other. Overall, our findings provide valuable insights into the structure-activity relationship of Vc1.1 with the α9α10 nAChR and will contribute to further development of more potent and specific Vc1.1 analogues.
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Affiliation(s)
- Xin Chu
- 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
| | - Han-Shen Tae
- Illawarra Health and Medical Research Institute (IHMRI), University of Wollongong, Wollongong, New South Wales 2522, Australia
| | - Qingliang Xu
- 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
| | - David J. Adams
- Illawarra Health and Medical Research Institute (IHMRI), University of Wollongong, Wollongong, New South Wales 2522, Australia
| | - 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
- Innovation Center for Marine Drug Screening & Evaluation, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266003, China
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Lebedev DS, Kryukova EV, Ivanov IA, Egorova NS, Timofeev ND, Spirova EN, Tufanova EY, Siniavin AE, Kudryavtsev DS, Kasheverov IE, Zouridakis M, Katsarava R, Zavradashvili N, Iagorshvili I, Tzartos SJ, Tsetlin VI. Oligoarginine Peptides, a New Family of Nicotinic Acetylcholine Receptor Inhibitors. Mol Pharmacol 2019; 96:664-673. [PMID: 31492697 DOI: 10.1124/mol.119.117713] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Accepted: 08/26/2019] [Indexed: 12/28/2022] Open
Abstract
Many peptide ligands of nicotinic acetylcholine receptors (nAChRs) contain a large number of positively charged amino acid residues, a striking example being conotoxins RgIA and GeXIVA from marine mollusk venom, with an arginine content of >30%. To determine whether peptides built exclusively from arginine residues will interact with different nAChR subtypes or with their structural homologs such as the acetylcholine-binding protein and ligand-binding domain of the nAChR α9 subunit, we synthesized a series of R3, R6, R8, and R16 oligoarginines and investigated their activity by competition with radioiodinated α-bungarotoxin, two-electrode voltage-clamp electrophysiology, and calcium imaging. R6 and longer peptides inhibited muscle-type nAChRs, α7 nAChRs, and α3β2 nAChRs in the micromolar range. The most efficient inhibition of ion currents was detected for muscle nAChR by R16 (IC50 = 157 nM) and for the α9α10 subtype by R8 and R16 (IC50 = 44 and 120 nM, respectively). Since the R8 affinity for other tested nAChRs was 100-fold lower, R8 appears to be a selective antagonist of α9α10 nAChR. For R8, the electrophysiological and competition experiments indicated the existence of two distinct binding sites on α9α10 nAChR. Since modified oligoarginines and other cationic molecules are widely used as cell-penetrating peptides, we studied several cationic polymers and demonstrated their nAChR inhibitory activity. SIGNIFICANT STATEMENT: By using radioligand analysis, electrophysiology, and calcium imaging, we found that oligoarginine peptides are a new group of inhibitors for muscle nicotinic acetylcholine receptors (nAChRs) and some neuronal nAChRs, the most active being those with 16 and 8 Arg residues. Such compounds and other cationic polymers are cell-penetrating tools for drug delivery, and we also demonstrated the inhibition of nAChRs for several of the latter. Possible positive and negative consequences of such an action should be taken into account.
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Affiliation(s)
- Dmitry S Lebedev
- Department of Molecular Neuroimmune Signaling, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia (D.S.L., E.V.K., I.A.I., N.S.E., N.D.T., E.N.S., E.Y.T., A.E.S., D.S.K., I.E.K., V.I.T.); Department of Neurobiology, Hellenic Pasteur Institute, Athens, Greece (M.Z., S.J.T.); Institute of Molecular Medicine, Sechenov First Moscow State Medical University, Moscow, Russia (I.E.K.); Institute of Chemistry and Molecular Engineering, Agricultural University of Georgia, Kakha Bendukidze University Campus, Tbilisi, Georgia (R.K., N.Z., I.I.); and PhysBio of MePhI, Moscow, Russia (V.I.T.)
| | - Elena V Kryukova
- Department of Molecular Neuroimmune Signaling, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia (D.S.L., E.V.K., I.A.I., N.S.E., N.D.T., E.N.S., E.Y.T., A.E.S., D.S.K., I.E.K., V.I.T.); Department of Neurobiology, Hellenic Pasteur Institute, Athens, Greece (M.Z., S.J.T.); Institute of Molecular Medicine, Sechenov First Moscow State Medical University, Moscow, Russia (I.E.K.); Institute of Chemistry and Molecular Engineering, Agricultural University of Georgia, Kakha Bendukidze University Campus, Tbilisi, Georgia (R.K., N.Z., I.I.); and PhysBio of MePhI, Moscow, Russia (V.I.T.)
| | - Igor A Ivanov
- Department of Molecular Neuroimmune Signaling, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia (D.S.L., E.V.K., I.A.I., N.S.E., N.D.T., E.N.S., E.Y.T., A.E.S., D.S.K., I.E.K., V.I.T.); Department of Neurobiology, Hellenic Pasteur Institute, Athens, Greece (M.Z., S.J.T.); Institute of Molecular Medicine, Sechenov First Moscow State Medical University, Moscow, Russia (I.E.K.); Institute of Chemistry and Molecular Engineering, Agricultural University of Georgia, Kakha Bendukidze University Campus, Tbilisi, Georgia (R.K., N.Z., I.I.); and PhysBio of MePhI, Moscow, Russia (V.I.T.)
| | - Natalia S Egorova
- Department of Molecular Neuroimmune Signaling, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia (D.S.L., E.V.K., I.A.I., N.S.E., N.D.T., E.N.S., E.Y.T., A.E.S., D.S.K., I.E.K., V.I.T.); Department of Neurobiology, Hellenic Pasteur Institute, Athens, Greece (M.Z., S.J.T.); Institute of Molecular Medicine, Sechenov First Moscow State Medical University, Moscow, Russia (I.E.K.); Institute of Chemistry and Molecular Engineering, Agricultural University of Georgia, Kakha Bendukidze University Campus, Tbilisi, Georgia (R.K., N.Z., I.I.); and PhysBio of MePhI, Moscow, Russia (V.I.T.)
| | - Nikita D Timofeev
- Department of Molecular Neuroimmune Signaling, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia (D.S.L., E.V.K., I.A.I., N.S.E., N.D.T., E.N.S., E.Y.T., A.E.S., D.S.K., I.E.K., V.I.T.); Department of Neurobiology, Hellenic Pasteur Institute, Athens, Greece (M.Z., S.J.T.); Institute of Molecular Medicine, Sechenov First Moscow State Medical University, Moscow, Russia (I.E.K.); Institute of Chemistry and Molecular Engineering, Agricultural University of Georgia, Kakha Bendukidze University Campus, Tbilisi, Georgia (R.K., N.Z., I.I.); and PhysBio of MePhI, Moscow, Russia (V.I.T.)
| | - Ekaterina N Spirova
- Department of Molecular Neuroimmune Signaling, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia (D.S.L., E.V.K., I.A.I., N.S.E., N.D.T., E.N.S., E.Y.T., A.E.S., D.S.K., I.E.K., V.I.T.); Department of Neurobiology, Hellenic Pasteur Institute, Athens, Greece (M.Z., S.J.T.); Institute of Molecular Medicine, Sechenov First Moscow State Medical University, Moscow, Russia (I.E.K.); Institute of Chemistry and Molecular Engineering, Agricultural University of Georgia, Kakha Bendukidze University Campus, Tbilisi, Georgia (R.K., N.Z., I.I.); and PhysBio of MePhI, Moscow, Russia (V.I.T.)
| | - Elizaveta Yu Tufanova
- Department of Molecular Neuroimmune Signaling, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia (D.S.L., E.V.K., I.A.I., N.S.E., N.D.T., E.N.S., E.Y.T., A.E.S., D.S.K., I.E.K., V.I.T.); Department of Neurobiology, Hellenic Pasteur Institute, Athens, Greece (M.Z., S.J.T.); Institute of Molecular Medicine, Sechenov First Moscow State Medical University, Moscow, Russia (I.E.K.); Institute of Chemistry and Molecular Engineering, Agricultural University of Georgia, Kakha Bendukidze University Campus, Tbilisi, Georgia (R.K., N.Z., I.I.); and PhysBio of MePhI, Moscow, Russia (V.I.T.)
| | - Andrei E Siniavin
- Department of Molecular Neuroimmune Signaling, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia (D.S.L., E.V.K., I.A.I., N.S.E., N.D.T., E.N.S., E.Y.T., A.E.S., D.S.K., I.E.K., V.I.T.); Department of Neurobiology, Hellenic Pasteur Institute, Athens, Greece (M.Z., S.J.T.); Institute of Molecular Medicine, Sechenov First Moscow State Medical University, Moscow, Russia (I.E.K.); Institute of Chemistry and Molecular Engineering, Agricultural University of Georgia, Kakha Bendukidze University Campus, Tbilisi, Georgia (R.K., N.Z., I.I.); and PhysBio of MePhI, Moscow, Russia (V.I.T.)
| | - Denis S Kudryavtsev
- Department of Molecular Neuroimmune Signaling, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia (D.S.L., E.V.K., I.A.I., N.S.E., N.D.T., E.N.S., E.Y.T., A.E.S., D.S.K., I.E.K., V.I.T.); Department of Neurobiology, Hellenic Pasteur Institute, Athens, Greece (M.Z., S.J.T.); Institute of Molecular Medicine, Sechenov First Moscow State Medical University, Moscow, Russia (I.E.K.); Institute of Chemistry and Molecular Engineering, Agricultural University of Georgia, Kakha Bendukidze University Campus, Tbilisi, Georgia (R.K., N.Z., I.I.); and PhysBio of MePhI, Moscow, Russia (V.I.T.)
| | - Igor E Kasheverov
- Department of Molecular Neuroimmune Signaling, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia (D.S.L., E.V.K., I.A.I., N.S.E., N.D.T., E.N.S., E.Y.T., A.E.S., D.S.K., I.E.K., V.I.T.); Department of Neurobiology, Hellenic Pasteur Institute, Athens, Greece (M.Z., S.J.T.); Institute of Molecular Medicine, Sechenov First Moscow State Medical University, Moscow, Russia (I.E.K.); Institute of Chemistry and Molecular Engineering, Agricultural University of Georgia, Kakha Bendukidze University Campus, Tbilisi, Georgia (R.K., N.Z., I.I.); and PhysBio of MePhI, Moscow, Russia (V.I.T.)
| | - Marios Zouridakis
- Department of Molecular Neuroimmune Signaling, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia (D.S.L., E.V.K., I.A.I., N.S.E., N.D.T., E.N.S., E.Y.T., A.E.S., D.S.K., I.E.K., V.I.T.); Department of Neurobiology, Hellenic Pasteur Institute, Athens, Greece (M.Z., S.J.T.); Institute of Molecular Medicine, Sechenov First Moscow State Medical University, Moscow, Russia (I.E.K.); Institute of Chemistry and Molecular Engineering, Agricultural University of Georgia, Kakha Bendukidze University Campus, Tbilisi, Georgia (R.K., N.Z., I.I.); and PhysBio of MePhI, Moscow, Russia (V.I.T.)
| | - Ramaz Katsarava
- Department of Molecular Neuroimmune Signaling, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia (D.S.L., E.V.K., I.A.I., N.S.E., N.D.T., E.N.S., E.Y.T., A.E.S., D.S.K., I.E.K., V.I.T.); Department of Neurobiology, Hellenic Pasteur Institute, Athens, Greece (M.Z., S.J.T.); Institute of Molecular Medicine, Sechenov First Moscow State Medical University, Moscow, Russia (I.E.K.); Institute of Chemistry and Molecular Engineering, Agricultural University of Georgia, Kakha Bendukidze University Campus, Tbilisi, Georgia (R.K., N.Z., I.I.); and PhysBio of MePhI, Moscow, Russia (V.I.T.)
| | - Nino Zavradashvili
- Department of Molecular Neuroimmune Signaling, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia (D.S.L., E.V.K., I.A.I., N.S.E., N.D.T., E.N.S., E.Y.T., A.E.S., D.S.K., I.E.K., V.I.T.); Department of Neurobiology, Hellenic Pasteur Institute, Athens, Greece (M.Z., S.J.T.); Institute of Molecular Medicine, Sechenov First Moscow State Medical University, Moscow, Russia (I.E.K.); Institute of Chemistry and Molecular Engineering, Agricultural University of Georgia, Kakha Bendukidze University Campus, Tbilisi, Georgia (R.K., N.Z., I.I.); and PhysBio of MePhI, Moscow, Russia (V.I.T.)
| | - Ia Iagorshvili
- Department of Molecular Neuroimmune Signaling, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia (D.S.L., E.V.K., I.A.I., N.S.E., N.D.T., E.N.S., E.Y.T., A.E.S., D.S.K., I.E.K., V.I.T.); Department of Neurobiology, Hellenic Pasteur Institute, Athens, Greece (M.Z., S.J.T.); Institute of Molecular Medicine, Sechenov First Moscow State Medical University, Moscow, Russia (I.E.K.); Institute of Chemistry and Molecular Engineering, Agricultural University of Georgia, Kakha Bendukidze University Campus, Tbilisi, Georgia (R.K., N.Z., I.I.); and PhysBio of MePhI, Moscow, Russia (V.I.T.)
| | - Socrates J Tzartos
- Department of Molecular Neuroimmune Signaling, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia (D.S.L., E.V.K., I.A.I., N.S.E., N.D.T., E.N.S., E.Y.T., A.E.S., D.S.K., I.E.K., V.I.T.); Department of Neurobiology, Hellenic Pasteur Institute, Athens, Greece (M.Z., S.J.T.); Institute of Molecular Medicine, Sechenov First Moscow State Medical University, Moscow, Russia (I.E.K.); Institute of Chemistry and Molecular Engineering, Agricultural University of Georgia, Kakha Bendukidze University Campus, Tbilisi, Georgia (R.K., N.Z., I.I.); and PhysBio of MePhI, Moscow, Russia (V.I.T.)
| | - Victor I Tsetlin
- Department of Molecular Neuroimmune Signaling, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia (D.S.L., E.V.K., I.A.I., N.S.E., N.D.T., E.N.S., E.Y.T., A.E.S., D.S.K., I.E.K., V.I.T.); Department of Neurobiology, Hellenic Pasteur Institute, Athens, Greece (M.Z., S.J.T.); Institute of Molecular Medicine, Sechenov First Moscow State Medical University, Moscow, Russia (I.E.K.); Institute of Chemistry and Molecular Engineering, Agricultural University of Georgia, Kakha Bendukidze University Campus, Tbilisi, Georgia (R.K., N.Z., I.I.); and PhysBio of MePhI, Moscow, Russia (V.I.T.)
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Li R, Li X, Jiang J, Tian Y, Liu D, Zhangsun D, Fu Y, Wu Y, Luo S. Interaction of rat α9α10 nicotinic acetylcholine receptor with α-conotoxin RgIA and Vc1.1: Insights from docking, molecular dynamics and binding free energy contributions. J Mol Graph Model 2019; 92:55-64. [PMID: 31330438 DOI: 10.1016/j.jmgm.2019.06.020] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2019] [Revised: 06/25/2019] [Accepted: 06/27/2019] [Indexed: 12/12/2022]
Abstract
The α9α10 nicotinic acetylcholine receptor (nAChR) is an effective therapeutic target for neuropathic pain. α-Conotoxin RgIA and Vc1.1 are two well-known peptides blocking α9α10 nAChR potently and selectively, which have been extensively investigated as drug candidates. Several key residues were established in previous experimental research. However, the mechanism of the specific interaction still needs to be elucidated in more detail. In this work, we explored the interaction mechanism between RgIA/Vc1.1 and rat α9α10 nAChR using docking and molecular dynamics (MD) simulations. Energy and network analysis programs were used to reveal key residues responsible for their interaction. Our results indicated that the most critical residues were in accord with previous studies. Importantly, several novel residues, including Tyr95, Trp151 in α9 (+)α10 (-) interface as well as Tyr196, Arg59in α10 (+)α9 (-) interface, were found in our models. Furthermore, we analyzed noncovalent interaction energies between RgIA/Vc1.1 and rat α9α10 nAChR. The results showed that three negatively charged residues (Glu197 in α10 subunit, Asp168 in α9 subunit and Asp205 in α10 subunit) were involved in the interaction between RgIA and rat α9α10 nAChR. In contrast, the interaction between Vc1.1 and rat α9α10 nAChR was mediated by the positively charged residues Arg59, Arg81 in α9 (-) subunit. These findings provided further insights into the molecular mechanisms of interaction between RgIA and Vc1.1 and rat α9α10 nAChR.
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Affiliation(s)
- Rui Li
- Key Laboratory of Tropical Biological Resources of Ministry of Education, Key Lab for Marine Drugs of Haikou, Hainan University, Haikou, Hainan, 570228, China
| | - Xincan Li
- Key Laboratory of Tropical Biological Resources of Ministry of Education, Key Lab for Marine Drugs of Haikou, Hainan University, Haikou, Hainan, 570228, China
| | - Jiemei Jiang
- Key Laboratory of Tropical Biological Resources of Ministry of Education, Key Lab for Marine Drugs of Haikou, Hainan University, Haikou, Hainan, 570228, China
| | - Yuanyuan Tian
- Key Laboratory of Tropical Biological Resources of Ministry of Education, Key Lab for Marine Drugs of Haikou, Hainan University, Haikou, Hainan, 570228, China
| | - Danrui Liu
- Key Laboratory of Tropical Biological Resources of Ministry of Education, Key Lab for Marine Drugs of Haikou, Hainan University, Haikou, Hainan, 570228, China
| | - Donting Zhangsun
- Key Laboratory of Tropical Biological Resources of Ministry of Education, Key Lab for Marine Drugs of Haikou, Hainan University, Haikou, Hainan, 570228, China
| | - Ying Fu
- Key Laboratory of Tropical Biological Resources of Ministry of Education, Key Lab for Marine Drugs of Haikou, Hainan University, Haikou, Hainan, 570228, China
| | - Yong Wu
- Key Laboratory of Tropical Biological Resources of Ministry of Education, Key Lab for Marine Drugs of Haikou, Hainan University, Haikou, Hainan, 570228, China.
| | - Sulan Luo
- Key Laboratory of Tropical Biological Resources of Ministry of Education, Key Lab for Marine Drugs of Haikou, Hainan University, Haikou, Hainan, 570228, China.
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Kryukova EV, Egorova NS, Kudryavtsev DS, Lebedev DS, Spirova EN, Zhmak MN, Garifulina AI, Kasheverov IE, Utkin YN, Tsetlin VI. From Synthetic Fragments of Endogenous Three-Finger Proteins to Potential Drugs. Front Pharmacol 2019; 10:748. [PMID: 31333465 PMCID: PMC6616073 DOI: 10.3389/fphar.2019.00748] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Accepted: 06/11/2019] [Indexed: 12/25/2022] Open
Abstract
The proteins of the Ly6 family have a three-finger folding as snake venom α-neurotoxins, targeting nicotinic acetylcholine receptors (nAChRs), and some of them, like mammalian secreted Ly6/uPAR protein (SLURP1) and membrane-attached Ly-6/neurotoxin (Lynx1), also interact with distinct nAChR subtypes. We believed that synthetic fragments of these endogenous proteins might open new ways for drug design because nAChRs are well-known targets for developing analgesics and drugs against neurodegenerative diseases. Since interaction with nAChRs was earlier shown for synthetic fragments of the α-neurotoxin central loop II, we synthesized a 15-membered fragment of human Lynx1, its form with two Cys residues added at the N- and C-termini and forming a disulfide, as well as similar forms of human SLURP1, SLURP2, and of Drosophila sleepless protein (SSS). The IC50 values measured in competition with radioiodinated α-bungarotoxin for binding to the membrane-bound Torpedo californica nAChR were 4.9 and 7.4 µM for Lynx1 and SSS fragments, but over 300 µM for SLURP1 or SLURP2 fragments. The affinity of these compounds for the α7 nAChR in the rat pituitary tumor-derived cell line GH4C1 was different: 13.1 and 147 µM for SSS and Lynx1 fragments, respectively. In competition for the ligand-binding domain of the α9 nAChR subunit, SSS and Lynx1 fragments had IC50 values of about 40 µM, which correlates with the value found for the latter with the rat α9α10 nAChR expressed in the Xenopus oocytes. Thus, the activity of these synthetic peptides against muscle-type and α9α10 nAChRs indicates that they may be useful in design of novel myorelaxants and analgesics.
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Affiliation(s)
- Elena V Kryukova
- Department of Molecular Neuroimmune Signalling, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Natalia S Egorova
- Department of Molecular Neuroimmune Signalling, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Denis S Kudryavtsev
- Department of Molecular Neuroimmune Signalling, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Dmitry S Lebedev
- Department of Molecular Neuroimmune Signalling, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Ekaterina N Spirova
- Department of Molecular Neuroimmune Signalling, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Maxim N Zhmak
- Department of Molecular Neuroimmune Signalling, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Aleksandra I Garifulina
- Department of Molecular Neuroimmune Signalling, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Igor E Kasheverov
- Department of Molecular Neuroimmune Signalling, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia.,Sechenov First Moscow State Medical University, Institute of Molecular Medicine, Moscow, Russia
| | - Yuri N Utkin
- Department of Molecular Neuroimmune Signalling, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Victor I Tsetlin
- Department of Molecular Neuroimmune Signalling, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia.,PhysBio of MEPhI, Moscow, Russia
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38
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Zouridakis M, Papakyriakou A, Ivanov IA, Kasheverov IE, Tsetlin V, Tzartos S, Giastas P. Crystal Structure of the Monomeric Extracellular Domain of α9 Nicotinic Receptor Subunit in Complex With α-Conotoxin RgIA: Molecular Dynamics Insights Into RgIA Binding to α9α10 Nicotinic Receptors. Front Pharmacol 2019; 10:474. [PMID: 31118896 PMCID: PMC6504684 DOI: 10.3389/fphar.2019.00474] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2018] [Accepted: 04/15/2019] [Indexed: 12/20/2022] Open
Abstract
The α9 subunit of nicotinic acetylcholine receptors (nAChRs) exists mainly in heteropentameric assemblies with α10. Accumulating data indicate the presence of three different binding sites in α9α10 nAChRs: the α9(+)/α9(−), the α9(+)/α10(−), and the α10(+)/α9(−). The major role of the principal (+) side of the extracellular domain (ECD) of α9 subunit in binding of the antagonists methyllylcaconitine and α-bungarotoxin was shown previously by the crystal structures of the monomeric α9-ECD with these molecules. Here we present the 2.26-Å resolution crystal structure of α9-ECD in complex with α-conotoxin (α-Ctx) RgIA, a potential drug for chronic pain, the first structure reported for a complex between an nAChR domain and an α-Ctx. Superposition of this structure with those of other α-Ctxs bound to the homologous pentameric acetylcholine binding proteins revealed significant similarities in the orientation of bound conotoxins, despite the monomeric state of the α9-ECD. In addition, ligand-binding studies calculated a binding affinity of RgIA to the α9-ECD at the low micromolar range. Given the high identity between α9 and α10 ECDs, particularly at their (+) sides, the presented structure was used as template for molecular dynamics simulations of the ECDs of the human α9α10 nAChR in pentameric assemblies. Our results support a favorable binding of RgIA at α9(+)/α9(−) or α10(+)/α9(−) rather than the α9(+)/α10(−) interface, in accordance with previous mutational and functional data.
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Affiliation(s)
- Marios Zouridakis
- Department of Neurobiology, Hellenic Pasteur Institute, Athens, Greece
| | | | - Igor A Ivanov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Igor E Kasheverov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia.,Institute of Molecular Medicine, Sechenov First Moscow State Medical University, Moscow, Russia
| | - Victor Tsetlin
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia.,PhysBio of MEPhI, Moscow, Russia
| | - Socrates Tzartos
- Department of Neurobiology, Hellenic Pasteur Institute, Athens, Greece.,Department of Pharmacy, University of Patras, Patras, Greece
| | - Petros Giastas
- Department of Neurobiology, Hellenic Pasteur Institute, Athens, Greece
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Utkin YN, Kuch U, Kasheverov IE, Lebedev DS, Cederlund E, Molles BE, Polyak I, Ivanov IA, Prokopev NA, Ziganshin RH, Jornvall H, Alvelius G, Chanhome L, Warrell DA, Mebs D, Bergman T, Tsetlin VI. Novel long-chain neurotoxins from Bungarus candidus distinguish the two binding sites in muscle-type nicotinic acetylcholine receptors. Biochem J 2019; 476:1285-302. [PMID: 30944155 DOI: 10.1042/BCJ20180909] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Revised: 03/16/2019] [Accepted: 04/03/2019] [Indexed: 12/30/2022]
Abstract
αδ-Bungarotoxins, a novel group of long-chain α-neurotoxins, manifest different affinity to two agonist/competitive antagonist binding sites of muscle-type nicotinic acetylcholine receptors (nAChRs), being more active at the interface of α-δ subunits. Three isoforms (αδ-BgTx-1-3) were identified in Malayan Krait (Bungarus candidus) from Thailand by genomic DNA analysis; two of them (αδ-BgTx-1 and 2) were isolated from its venom. The toxins comprise 73 amino acid residues and 5 disulfide bridges, being homologous to α-bungarotoxin (α-BgTx), a classical blocker of muscle-type and neuronal α7, α8, and α9α10 nAChRs. The toxicity of αδ-BgTx-1 (LD50 = 0.17-0.28 µg/g mouse, i.p. injection) is essentially as high as that of α-BgTx. In the chick biventer cervicis nerve-muscle preparation, αδ-BgTx-1 completely abolished acetylcholine response, but in contrast with the block by α-BgTx, acetylcholine response was fully reversible by washing. αδ-BgTxs, similar to α-BgTx, bind with high affinity to α7 and muscle-type nAChRs. However, the major difference of αδ-BgTxs from α-BgTx and other naturally occurring α-neurotoxins is that αδ-BgTxs discriminate the two binding sites in the Torpedo californica and mouse muscle nAChRs showing up to two orders of magnitude higher affinity for the α-δ site as compared with α-ε or α-γ binding site interfaces. Molecular modeling and analysis of the literature provided possible explanations for these differences in binding mode; one of the probable reasons being the lower content of positively charged residues in αδ-BgTxs. Thus, αδ-BgTxs are new tools for studies on nAChRs.
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Ren J, Zhu X, Xu P, Li R, Fu Y, Dong S, Zhangsun D, Wu Y, Luo S. d-Amino Acid Substitution of α-Conotoxin RgIA Identifies its Critical Residues and Improves the Enzymatic Stability. Mar Drugs 2019; 17:md17030142. [PMID: 30823399 PMCID: PMC6472032 DOI: 10.3390/md17030142] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2018] [Revised: 02/17/2019] [Accepted: 02/22/2019] [Indexed: 12/22/2022] Open
Abstract
α-Conotoxin RgIA is a selective and potent competitive antagonist of rat α9α10 nicotinic acetylcholine receptors (nAChR), but it is much less potent towards human α9α10 nAChR. Furthermore, RgIA is susceptible to proteolytic degradation due to containing four arginine residues. These disadvantages greatly limit its use for clinical applications. The purpose of this research was to identify critical stereocenters of RgIA and discover more stable analogues, enhancing its bioavailability by using the d-amino acid scan method. The activity of each variant was investigated against rat and human α9α10 nAChRs, which were expressed in Xenopus oocytes. Experimental assays showed that 14 out of 15 analogues had a substantial reduction in potency towards rat α9α10 nAChR. Noticeably, analogue 13 retained full biological activity compared with RgIA. Meanwhile, two other analogues, 14 and 15, of which l-Args were substituted with d-Args, exhibited a significantly increased potency towards human α9α10 nAChR, although these analogues showed decreased activities against rat α9α10 nAChR. Additionally, these three analogues exhibited a high resistance against enzymatic degradation in human serum and simulated intestinal fluid (SIF). Collectively, our findings suggest that a d-amino acid scan is a useful strategy for investigating how the side-chain chirality of amino acids affects the structure and function of peptides and may facilitate the development of more stable analogues to increase therapeutic potential.
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Affiliation(s)
- Jie Ren
- Key Laboratory of Tropical Biological Resources, Ministry of Education, Key Lab for Marine Drugs of Haikou, Hainan University, Haikou 570228, China.
| | - Xiaopeng Zhu
- Key Laboratory of Tropical Biological Resources, Ministry of Education, Key Lab for Marine Drugs of Haikou, Hainan University, Haikou 570228, China.
| | - Pan Xu
- Key Laboratory of Tropical Biological Resources, Ministry of Education, Key Lab for Marine Drugs of Haikou, Hainan University, Haikou 570228, China.
| | - Rui Li
- Key Laboratory of Tropical Biological Resources, Ministry of Education, Key Lab for Marine Drugs of Haikou, Hainan University, Haikou 570228, China.
| | - Ying Fu
- Key Laboratory of Tropical Biological Resources, Ministry of Education, Key Lab for Marine Drugs of Haikou, Hainan University, Haikou 570228, China.
| | - Shuai Dong
- Key Laboratory of Tropical Biological Resources, Ministry of Education, Key Lab for Marine Drugs of Haikou, Hainan University, Haikou 570228, China.
| | - Dongting Zhangsun
- Key Laboratory of Tropical Biological Resources, Ministry of Education, Key Lab for Marine Drugs of Haikou, Hainan University, Haikou 570228, China.
| | - Yong Wu
- Key Laboratory of Tropical Biological Resources, Ministry of Education, Key Lab for Marine Drugs of Haikou, Hainan University, Haikou 570228, China.
| | - Sulan Luo
- Key Laboratory of Tropical Biological Resources, Ministry of Education, Key Lab for Marine Drugs of Haikou, Hainan University, Haikou 570228, China.
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Kulbatskii DS, Bychkov ML, Lyukmanova EN. Human Nicotinic Acetylcholine Receptors: Part I—Structure, Function, and Role in Neuromuscular Transmission and CNS Functioning. Russ J Bioorg Chem 2019. [DOI: 10.1134/s1068162018060043] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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42
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Turner MW, Marquart LA, Phillips PD, McDougal OM. Mutagenesis of α-Conotoxins for Enhancing Activity and Selectivity for Nicotinic Acetylcholine Receptors. Toxins (Basel) 2019; 11:E113. [PMID: 30781866 DOI: 10.3390/toxins11020113] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2019] [Revised: 02/10/2019] [Accepted: 02/11/2019] [Indexed: 02/04/2023] Open
Abstract
Nicotinic acetylcholine receptors (nAChRs) are found throughout the mammalian body and have been studied extensively because of their implication in a myriad of diseases. α-Conotoxins (α-CTxs) are peptide neurotoxins found in the venom of marine snails of genus Conus. α-CTxs are potent and selective antagonists for a variety of nAChR isoforms. Over the past 40 years, α-CTxs have proven to be valuable molecular probes capable of differentiating between closely related nAChR subtypes and have contributed greatly to understanding the physiological role of nAChRs in the mammalian nervous system. Here, we review the amino acid composition and structure of several α-CTxs that selectively target nAChR isoforms and explore strategies and outcomes for introducing mutations in native α-CTxs to direct selectivity and enhance binding affinity for specific nAChRs. This review will focus on structure-activity relationship studies involving native α-CTxs that have been rationally mutated and molecular interactions that underlie binding between ligand and nAChR isoform.
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Kryukova EV, Ivanov IA, Lebedev DS, Spirova EN, Egorova NS, Zouridakis M, Kasheverov IE, Tzartos SJ, Tsetlin VI. Orthosteric and/or Allosteric Binding of α-Conotoxins to Nicotinic Acetylcholine Receptors and Their Models. Mar Drugs 2018; 16:md16120460. [PMID: 30469507 PMCID: PMC6315749 DOI: 10.3390/md16120460] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Revised: 11/09/2018] [Accepted: 11/20/2018] [Indexed: 12/19/2022] Open
Abstract
α-Conotoxins from Conus snails are capable of distinguishing muscle and neuronal nicotinic acetylcholine receptors (nAChRs). α-Conotoxin RgIA and αO-conotoxin GeXIVA, blocking neuronal α9α10 nAChR, are potential analgesics. Typically, α-conotoxins bind to the orthosteric sites for agonists/competitive antagonists, but αO-conotoxin GeXIVA was proposed to attach allosterically, judging by electrophysiological experiments on α9α10 nAChR. We decided to verify this conclusion by radioligand analysis in competition with α-bungarotoxin (αBgt) on the ligand-binding domain of the nAChR α9 subunit (α9 LBD), where, from the X-ray analysis, αBgt binds at the orthosteric site. A competition with αBgt was registered for GeXIVA and RgIA, IC50 values being in the micromolar range. However, high nonspecific binding of conotoxins (detected with their radioiodinated derivatives) to His6-resin attaching α9 LBD did not allow us to accurately measure IC50s. However, IC50s were measured for binding to Aplysia californica AChBP: the RgIA globular isomer, known to be active against α9α10 nAChR, was more efficient than the ribbon one, whereas all three GeXIVA isomers had similar potencies at low µM. Thus, radioligand analysis indicated that both conotoxins can attach to the orthosteric sites in these nAChR models, which should be taken into account in the design of analgesics on the basis of these conotoxins.
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Affiliation(s)
- Elena V Kryukova
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Miklukho-Maklaya Street, 16/10, 117997 Moscow, Russia.
| | - Igor A Ivanov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Miklukho-Maklaya Street, 16/10, 117997 Moscow, Russia.
| | - Dmitry S Lebedev
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Miklukho-Maklaya Street, 16/10, 117997 Moscow, Russia.
| | - Ekaterina N Spirova
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Miklukho-Maklaya Street, 16/10, 117997 Moscow, Russia.
| | - Natalia S Egorova
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Miklukho-Maklaya Street, 16/10, 117997 Moscow, Russia.
| | - Marios Zouridakis
- Department of Neurobiology, Hellenic Pasteur Institute, 127, Vas. Sofias ave., Athens 115 21, Greece.
| | - Igor E Kasheverov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Miklukho-Maklaya Street, 16/10, 117997 Moscow, Russia.
- Institute of Molecular Medicine, Sechenov First Moscow State Medical University, Trubetskaya Street 8, bld. 2, 119991 Moscow, Russia.
| | - Socrates J Tzartos
- Department of Neurobiology, Hellenic Pasteur Institute, 127, Vas. Sofias ave., Athens 115 21, Greece.
| | - Victor I Tsetlin
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Miklukho-Maklaya Street, 16/10, 117997 Moscow, Russia.
- PhysBio of MEPhI, Kashirskoye Ave., 31, 115409 Moscow, Russia.
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Ren J, Li R, Ning J, Zhu X, Zhangsun D, Wu Y, Luo S. Effect of Methionine Oxidation and Substitution of α-Conotoxin TxID on α3β4 Nicotinic Acetylcholine Receptor. Mar Drugs 2018; 16:md16060215. [PMID: 29925760 PMCID: PMC6025358 DOI: 10.3390/md16060215] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2018] [Revised: 06/05/2018] [Accepted: 06/15/2018] [Indexed: 12/24/2022] Open
Abstract
α-Conotoxin TxID was discovered from Conus textile by gene cloning, which has 4/6 inter-cysteine loop spacing and selectively inhibits α3β4 nicotinic acetylcholine receptor (nAChR) subtype. However, TxID is susceptible to modification due to it containing a methionine (Met) residue that easily forms methionine sulfoxide (MetO) in oxidative environment. In this study, we investigated how Met-11 and its derivatives affect the activity of TxID using a combination of electrophysiological recordings and molecular modelling. The results showed most TxID analogues had substantially decreased activities on α3β4 nAChR with more than 10-fold potency loss and 5 of them demonstrated no inhibition on α3β4 nAChR. However, one mutant, [M11I]TxID, displayed potent inhibition at α3β4 nAChR with an IC50 of 69 nM, which only exhibited 3.8-fold less compared with TxID. Molecular dynamics simulations were performed to expound the decrease in the affinity for α3β4 nAChR. The results indicate replacement of Met with a hydrophobic moderate-sized Ile in TxID is an alternative strategy to reduce the impact of Met oxidation, which may help to redesign conotoxins containing methionine residue.
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Affiliation(s)
- Jie Ren
- Key Laboratory of Tropical Biological Resources, Ministry of Education, Key Laboratory for Marine Drugs of Haikou, Hainan University, Haikou 570228, China.
- Institute of Tropical Agriculture and Forestry, Hainan University, Haikou 570228, China.
| | - Rui Li
- Key Laboratory of Tropical Biological Resources, Ministry of Education, Key Laboratory for Marine Drugs of Haikou, Hainan University, Haikou 570228, China.
| | - Jiong Ning
- Key Laboratory of Tropical Biological Resources, Ministry of Education, Key Laboratory for Marine Drugs of Haikou, Hainan University, Haikou 570228, China.
| | - Xiaopeng Zhu
- Key Laboratory of Tropical Biological Resources, Ministry of Education, Key Laboratory for Marine Drugs of Haikou, Hainan University, Haikou 570228, China.
| | - Dongting Zhangsun
- Key Laboratory of Tropical Biological Resources, Ministry of Education, Key Laboratory for Marine Drugs of Haikou, Hainan University, Haikou 570228, China.
| | - Yong Wu
- Key Laboratory of Tropical Biological Resources, Ministry of Education, Key Laboratory for Marine Drugs of Haikou, Hainan University, Haikou 570228, China.
| | - Sulan Luo
- Key Laboratory of Tropical Biological Resources, Ministry of Education, Key Laboratory for Marine Drugs of Haikou, Hainan University, Haikou 570228, China.
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Abstract
Marine cone snails are a large family of gastropods that have evolved highly potent venoms for predation and defense. The cone snail venom has exceptional molecular diversity in neuropharmacologically active compounds, targeting a range of receptors, ion channels, and transporters. These conotoxins have helped to dissect the structure and function of many of these therapeutically significant targets in the central and peripheral nervous systems, as well as unravelling the complex cellular mechanisms modulated by these receptors and ion channels. This review provides an overview of α-conotoxins targeting neuronal nicotinic acetylcholine receptors. The structure and activity of both classical and non-classical α-conotoxins are discussed, along with their contributions towards understanding nicotinic acetylcholine receptor (nAChR) structure and function.
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Affiliation(s)
- Nikita Abraham
- IMB Centre for Pain Research, Institute for Molecular Bioscience, The University of Queensland, St. Lucia, QLD 4072, Australia.
| | - Richard J Lewis
- IMB Centre for Pain Research, Institute for Molecular Bioscience, The University of Queensland, St. Lucia, QLD 4072, Australia.
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Manetti D, Bellucci C, Chiaramonte N, Dei S, Teodori E, Romanelli MN. Designing selective modulators for the nicotinic receptor subtypes: challenges and opportunities. Future Med Chem 2018; 10:433-59. [PMID: 29451400 DOI: 10.4155/fmc-2017-0169] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Nicotinic receptors are membrane proteins involved in several physiological processes. They are considered suitable drug targets for various CNS disorders or conditions, as shown by the large number of compounds which have entered clinical trials. In recent years, nonconventional agonists have been discovered: positive allosteric modulators, allosteric agonists, site-specific agonists and silent desensitizers are compounds able to modulate the receptor interacting at sites different from the orthodox one, or to desensitize the receptor without prior opening. While these new findings can further complicate the pharmacology of these proteins and the design and optimization of ligands, they undoubtedly offer new opportunities to find drugs for the many therapeutic indications involving nicotinic receptors.
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47
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Shen XM, Brengman JM, Shen S, Durmus H, Preethish-Kumar V, Yuceyar N, Vengalil S, Nalini A, Deymeer F, Sine SM, Engel AG. Mutations causing congenital myasthenia reveal principal coupling pathway in the acetylcholine receptor ε-subunit. JCI Insight 2018; 3:97826. [PMID: 29367459 DOI: 10.1172/jci.insight.97826] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2017] [Accepted: 12/12/2017] [Indexed: 11/17/2022] Open
Abstract
We identify 2 homozygous mutations in the ε-subunit of the muscle acetylcholine receptor (AChR) in 3 patients with severe congenital myasthenia: εR218W in the pre-M1 region in 2 patients and εE184K in the β8-β9 linker in 1 patient. Arg218 is conserved in all eukaryotic members of the Cys-loop receptor superfamily, while Glu184 is conserved in the α-, δ-, and ε-subunits of AChRs from all species. εR218W reduces channel gating efficiency 338-fold and AChR expression on the cell surface 5-fold, whereas εE184K reduces channel gating efficiency 11-fold but does not alter AChR cell surface expression. Determinations of the effective channel gating rate constants, combined with mutant cycle analyses, demonstrate strong energetic coupling between εR218 and εE184, and between εR218 and εE45 from the β1-β2 linker, as also observed for equivalent residues in the principal coupling pathway of the α-subunit. Thus, efficient and rapid gating of the AChR channel is achieved not only by coupling between conserved residues within the principal coupling pathway of the α-subunit, but also between corresponding residues in the ε-subunit.
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Affiliation(s)
- Xin-Ming Shen
- Department of Neurology and Neuromuscular Research Laboratory, Mayo Clinic, Rochester, Minnesota, USA
| | - Joan M Brengman
- Department of Neurology and Neuromuscular Research Laboratory, Mayo Clinic, Rochester, Minnesota, USA
| | - Shelley Shen
- Department of Neurology and Neuromuscular Research Laboratory, Mayo Clinic, Rochester, Minnesota, USA
| | - Hacer Durmus
- Department of Neurology, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Turkey
| | - Veeramani Preethish-Kumar
- Department of Neurology and.,Clinical Neurosciences, National Institute of Mental Health and Neurosciences, Bangalore, India
| | - Nur Yuceyar
- Department of Neurology, Ege University, Izmir, Turkey
| | | | | | - Feza Deymeer
- Department of Neurology, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Turkey
| | - Steven M Sine
- Department of Neurology and Neuromuscular Research Laboratory, Mayo Clinic, Rochester, Minnesota, USA.,Departments of Physiology and Biomedical Engineering and of Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, Minnesota, USA
| | - Andrew G Engel
- Department of Neurology and Neuromuscular Research Laboratory, Mayo Clinic, Rochester, Minnesota, USA
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Mosesso R, Dougherty DA. A triad of residues is functionally transferrable between 5-HT 3 serotonin receptors and nicotinic acetylcholine receptors. J Biol Chem 2018; 293:2903-2914. [PMID: 29298898 DOI: 10.1074/jbc.m117.810432] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2017] [Revised: 11/29/2017] [Indexed: 11/06/2022] Open
Abstract
Cys-loop receptors are pentameric ligand-gated ion channels that facilitate communication within the nervous system. Upon neurotransmitter binding, these receptors undergo an allosteric activation mechanism connecting the binding event to the membrane-spanning channel pore, which expands to conduct ions. Some of the earliest steps in this activation mechanism are carried out by residues proximal to the binding site, the relative positioning of which may reflect functional differences among members of the Cys-loop family of receptors. Herein, we investigated key side-chain interactions near the binding site via mutagenesis and two-electrode voltage-clamp electrophysiology in serotonin-gated 5-HT3A receptors (5-HT3ARs) and nicotinic acetylcholine receptors (nAChRs) expressed in Xenopus laevis oocytes. We found that a triad of residues aligning to Thr-152, Glu-209, and Lys-211 in the 5-HT3AR can be exchanged between the homomeric 5-HT3AR and the muscle-type nAChR α-subunit with small functional consequences. Via triple mutant cycle analysis, we demonstrated that this triad forms an interdependent network in the muscle-type nAChR. Furthermore, nAChR-type mutations of the 5-HT3AR affect the affinity of nicotine, a competitive antagonist of 5-HT3ARs, in a cooperative manner. Using mutant cycle analyses between the 5-HT3A triad, loop A residues Asn-101 and Glu-102, β9 residue Lys-197, and the channel gate at Thr-257, we observed that residues in this region are energetically linked to the channel gate and are particularly sensitive to mutations that introduce a net positive charge. This study expands our understanding of the differences and similarities in the activation mechanisms of Cys-loop receptors.
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Affiliation(s)
- Richard Mosesso
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125
| | - Dennis A Dougherty
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125.
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Vulfius CA, Kasheverov IE, Kryukova EV, Spirova EN, Shelukhina IV, Starkov VG, Andreeva TV, Faure G, Zouridakis M, Tsetlin VI, Utkin YN. Pancreatic and snake venom presynaptically active phospholipases A2 inhibit nicotinic acetylcholine receptors. PLoS One 2017; 12:e0186206. [PMID: 29023569 PMCID: PMC5638340 DOI: 10.1371/journal.pone.0186206] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Accepted: 09/27/2017] [Indexed: 01/08/2023] Open
Abstract
Phospholipases A2 (PLA2s) are enzymes found throughout the animal kingdom. They hydrolyze phospholipids in the sn-2 position producing lysophospholipids and unsaturated fatty acids, agents that can damage membranes. PLA2s from snake venoms have numerous toxic effects, not all of which can be explained by phospholipid hydrolysis, and each enzyme has a specific effect. We have earlier demonstrated the capability of several snake venom PLA2s with different enzymatic, cytotoxic, anticoagulant and antiproliferative properties, to decrease acetylcholine-induced currents in Lymnaea stagnalis neurons, and to compete with α-bungarotoxin for binding to nicotinic acetylcholine receptors (nAChRs) and acetylcholine binding protein. Since nAChRs are implicated in postsynaptic and presynaptic activities, in this work we probe those PLA2s known to have strong presynaptic effects, namely β-bungarotoxin from Bungarus multicinctus and crotoxin from Crotalus durissus terrificus. We also wished to explore whether mammalian PLA2s interact with nAChRs, and have examined non-toxic PLA2 from porcine pancreas. It was found that porcine pancreatic PLA2 and presynaptic β-bungarotoxin blocked currents mediated by nAChRs in Lymnaea neurons with IC50s of 2.5 and 4.8 μM, respectively. Crotoxin competed with radioactive α-bungarotoxin for binding to Torpedo and human α7 nAChRs and to the acetylcholine binding protein. Pancreatic PLA2 interacted similarly with these targets; moreover, it inhibited radioactive α-bungarotoxin binding to the water-soluble extracellular domain of human α9 nAChR, and blocked acetylcholine induced currents in human α9α10 nAChRs heterologously expressed in Xenopus oocytes. These and our earlier results show that all snake PLA2s, including presynaptically active crotoxin and β-bungarotoxin, as well as mammalian pancreatic PLA2, interact with nAChRs. The data obtained suggest that this interaction may be a general property of all PLA2s, which should be proved by further experiments.
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Affiliation(s)
- Catherine A. Vulfius
- Institute of Cell Biophysics, Russian Academy of Sciences, Pushchino, Moscow Region, Russia
| | - Igor E. Kasheverov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Elena V. Kryukova
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Ekaterina N. Spirova
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Irina V. Shelukhina
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Vladislav G. Starkov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Tatyana V. Andreeva
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Grazyna Faure
- Unité Récepteurs-Canaux, Institut Pasteur, Paris, France
| | | | - Victor I. Tsetlin
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Yuri N. Utkin
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
- * E-mail:
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Chiodo L, Malliavin T, Maragliano L, Cottone G. A possible desensitized state conformation of the human α 7 nicotinic receptor: A molecular dynamics study. Biophys Chem 2017; 229:99-109. [DOI: 10.1016/j.bpc.2017.06.010] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2017] [Revised: 06/22/2017] [Accepted: 06/22/2017] [Indexed: 11/18/2022]
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