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Bennetts FM, Venugopal H, Glukhova A, Mobbs JI, Ventura S, Thal DM. Structural insights into the human P2X1 receptor and ligand interactions. Nat Commun 2024; 15:8418. [PMID: 39341830 PMCID: PMC11439047 DOI: 10.1038/s41467-024-52776-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2024] [Accepted: 09/20/2024] [Indexed: 10/01/2024] Open
Abstract
The P2X1 receptor is a trimeric ligand-gated ion channel that plays an important role in urogenital and immune functions, offering the potential for new drug treatments. However, progress in this area has been hindered by limited structural information and a lack of well-characterised tool compounds. In this study, we employ cryogenic electron microscopy (cryo-EM) to elucidate the structures of the P2X1 receptor in an ATP-bound desensitised state and an NF449-bound closed state. NF449, a potent P2X1 receptor antagonist, engages the receptor distinctively, while ATP, the endogenous ligand, binds in a manner consistent with other P2X receptors. To explore the molecular basis of receptor inhibition, activation, and ligand interactions, key residues involved in ligand and metal ion binding were mutated. Radioligand binding assays with [3H]-α,β-methylene ATP and intracellular calcium ion influx assays were used to evaluate the effects of these mutations. These experiments validate key ligand-receptor interactions and identify conserved and non-conserved residues critical for ligand binding or receptor modulation. This research expands our understanding of the P2X1 receptor structure at a molecular level and opens new avenues for in silico drug design targeting the P2X1 receptor.
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Affiliation(s)
- Felix M Bennetts
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, Australia
- Australian Research Council Centre for Cryo-Electron Microscopy of Membrane Proteins, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, Australia
| | - Hariprasad Venugopal
- Ramaciotti Centre for Cryo-Electron Microscopy, Monash University, Clayton, VIC, Australia
| | - Alisa Glukhova
- Australian Research Council Centre for Cryo-Electron Microscopy of Membrane Proteins, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, Australia
- Structural Biology Division, Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia
| | - Jesse I Mobbs
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, Australia.
- Australian Research Council Centre for Cryo-Electron Microscopy of Membrane Proteins, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, Australia.
| | - Sabatino Ventura
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, Australia.
| | - David M Thal
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, Australia.
- Australian Research Council Centre for Cryo-Electron Microscopy of Membrane Proteins, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, Australia.
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2
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Oken AC, Lisi NE, Krishnamurthy I, McCarthy AE, Godsey MH, Glasfeld A, Mansoor SE. High-affinity agonism at the P2X 7 receptor is mediated by three residues outside the orthosteric pocket. Nat Commun 2024; 15:6662. [PMID: 39107314 PMCID: PMC11303814 DOI: 10.1038/s41467-024-50771-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2024] [Accepted: 07/19/2024] [Indexed: 08/10/2024] Open
Abstract
P2X receptors are trimeric ATP-gated ion channels that activate diverse signaling cascades. Due to its role in apoptotic pathways, selective activation of P2X7 is a potential experimental tool and therapeutic approach in cancer biology. However, mechanisms of high-affinity P2X7 activation have not been defined. We report high-resolution cryo-EM structures of wild-type rat P2X7 bound to the high-affinity agonist BzATP as well as significantly improved apo receptor structures in the presence and absence of sodium. Apo structures define molecular details of pore architecture and reveal how a partially hydrated Na+ ion interacts with the conductance pathway in the closed state. Structural, electrophysiological, and direct binding data of BzATP reveal that three residues just outside the orthosteric ATP-binding site are responsible for its high-affinity agonism. This work provides insights into high-affinity agonism for any P2X receptor and lays the groundwork for development of subtype-specific agonists applicable to cancer therapeutics.
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Affiliation(s)
- Adam C Oken
- Department of Chemical Physiology & Biochemistry, Oregon Health & Science University, Portland, OR, 97239, USA
| | - Nicolas E Lisi
- Department of Chemical Physiology & Biochemistry, Oregon Health & Science University, Portland, OR, 97239, USA
| | - Ipsita Krishnamurthy
- Department of Chemical Physiology & Biochemistry, Oregon Health & Science University, Portland, OR, 97239, USA
| | - Alanna E McCarthy
- Division of Cardiovascular Medicine, Knight Cardiovascular Institute, Oregon Health & Science University, Portland, OR, 97239, USA
| | - Michael H Godsey
- Department of Chemical Physiology & Biochemistry, Oregon Health & Science University, Portland, OR, 97239, USA
| | - Arthur Glasfeld
- Department of Chemical Physiology & Biochemistry, Oregon Health & Science University, Portland, OR, 97239, USA
| | - Steven E Mansoor
- Department of Chemical Physiology & Biochemistry, Oregon Health & Science University, Portland, OR, 97239, USA.
- Division of Cardiovascular Medicine, Knight Cardiovascular Institute, Oregon Health & Science University, Portland, OR, 97239, USA.
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3
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Sierra-Marquez J, Schaller L, Sassenbach L, Ramírez-Fernández A, Alt P, Rissiek B, Zimmer B, Schredelseker J, Hector J, Stähler T, Koch-Nolte F, Staab-Weijnitz CA, Dietrich A, Kopp R, Nicke A. Different localization of P2X4 and P2X7 receptors in native mouse lung - lack of evidence for a direct P2X4-P2X7 receptor interaction. Front Immunol 2024; 15:1425938. [PMID: 38953020 PMCID: PMC11215518 DOI: 10.3389/fimmu.2024.1425938] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2024] [Accepted: 05/28/2024] [Indexed: 07/03/2024] Open
Abstract
Introduction P2X receptors are a family of homo- and heterotrimeric cation channels gated by extracellular ATP. The P2X4 and P2X7 subunits show overlapping expression patterns and have been involved in similar physiological processes, such as pain and inflammation as well as various immune cell functions. While formation of P2X2/P2X3 heterotrimers produces a distinct pharmacological phenotype and has been well established, functional identification of a P2X4/P2X7 heteromer has been difficult and evidence for and against a physical association has been found. Most of this evidence stems, however, from in vitro model systems. Methods Here, we used a P2X7-EGFP BAC transgenic mouse model as well as P2X4 and P2X7 knock-out mice to re-investigate a P2X4-P2X7 interaction in mouse lung by biochemical and immunohistochemical experiments as well as quantitative expression analysis. Results No detectable amounts of P2X4 could be co-purified from mouse lung via P2X7-EGFP. In agreement with these findings, immuno-histochemical analysis using a P2X7-specific nanobody revealed only limited overlap in the cellular and subcellular localizations of P2X4 and P2X7 in both the native lung tissue and primary cells. Comparison of P2X4 and P2X7 transcript and protein levels in the respective gene-deficient and wild type mice showed no mutual interrelation between their expression levels in whole lungs. However, a significantly reduced P2rx7 expression was found in alveolar macrophages of P2rx4 -/- mice. Discussion In summary, our detailed analysis of the cellular and subcellular P2X4 and P2X7 localization and expression does not support a physiologically relevant direct association of P2X4 and P2X7 subunits or receptors in vivo.
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Affiliation(s)
- Juan Sierra-Marquez
- Walther Straub Institute of Pharmacology and Toxicology, Member of the German Center for Lung Research (DZL), Faculty of Medicine, LMU Munich, Munich, Germany
| | - Lena Schaller
- Walther Straub Institute of Pharmacology and Toxicology, Member of the German Center for Lung Research (DZL), Faculty of Medicine, LMU Munich, Munich, Germany
| | - Lukas Sassenbach
- Walther Straub Institute of Pharmacology and Toxicology, Member of the German Center for Lung Research (DZL), Faculty of Medicine, LMU Munich, Munich, Germany
| | - Antonio Ramírez-Fernández
- Walther Straub Institute of Pharmacology and Toxicology, Member of the German Center for Lung Research (DZL), Faculty of Medicine, LMU Munich, Munich, Germany
| | - Philipp Alt
- Walther Straub Institute of Pharmacology and Toxicology, Member of the German Center for Lung Research (DZL), Faculty of Medicine, LMU Munich, Munich, Germany
| | - Björn Rissiek
- Department of Neurology, University Medical Centre Hamburg-Eppendorf, Hamburg, Germany
| | - Béla Zimmer
- Walther Straub Institute of Pharmacology and Toxicology, Member of the German Center for Lung Research (DZL), Faculty of Medicine, LMU Munich, Munich, Germany
| | - Johann Schredelseker
- Walther Straub Institute of Pharmacology and Toxicology, Member of the German Center for Lung Research (DZL), Faculty of Medicine, LMU Munich, Munich, Germany
- Deutsches Zentrum für Herz-Kreislauf-Forschung, Partner Site Munich Heart Alliance, Munich, Germany
| | - Julia Hector
- Walther Straub Institute of Pharmacology and Toxicology, Member of the German Center for Lung Research (DZL), Faculty of Medicine, LMU Munich, Munich, Germany
| | - Tobias Stähler
- Institute of Immunology, University Medical Centre Hamburg-Eppendorf, Hamburg, Germany
| | - Friedrich Koch-Nolte
- Institute of Immunology, University Medical Centre Hamburg-Eppendorf, Hamburg, Germany
| | - Claudia A. Staab-Weijnitz
- Institute of Lung Health and Immunity (LHI), Helmholtz Munich, Comprehensive Pneumology Center (CPC-M), Member of the German Center for Lung Research (DZL), Germany
- Department of Pediatrics, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Alexander Dietrich
- Walther Straub Institute of Pharmacology and Toxicology, Member of the German Center for Lung Research (DZL), Faculty of Medicine, LMU Munich, Munich, Germany
| | - Robin Kopp
- Walther Straub Institute of Pharmacology and Toxicology, Member of the German Center for Lung Research (DZL), Faculty of Medicine, LMU Munich, Munich, Germany
| | - Annette Nicke
- Walther Straub Institute of Pharmacology and Toxicology, Member of the German Center for Lung Research (DZL), Faculty of Medicine, LMU Munich, Munich, Germany
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4
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Nagel J, Törmäkangas O, Kuokkanen K, El-Tayeb A, Messinger J, Abdelrahman A, Bous C, Schiedel AC, Müller CE. Preparation and preliminary evaluation of a tritium-labeled allosteric P2X4 receptor antagonist. Purinergic Signal 2024:10.1007/s11302-024-10005-2. [PMID: 38795223 DOI: 10.1007/s11302-024-10005-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2024] [Accepted: 03/26/2024] [Indexed: 05/27/2024] Open
Abstract
P2X4 receptors are ATP-gated cation channels that were proposed as novel drug targets due to their role in inflammation and neuropathic pain. Only few potent and selective P2X4 receptor antagonists have been described to date. Labeled tool compounds suitable for P2X4 receptor binding studies are lacking. Here, we present a novel allosteric P2X4 receptor antagonist possessing high potency in the low nanomolar range. We describe its tritium-labeling resulting in the P2X4-selective radiotracer [3H]PSB-OR-2020 with high specific activity (45 Ci/mmol; 1.67 TBq/mmol). A radioligand binding assay was developed using human embryonic kidney (HEK293) cell membranes recombinantly expressing the human P2X4 receptor. Competition binding studies with structurally diverse P2X4 receptor antagonists revealed different allosteric binding sites indicating that the new class of P2X4 receptor antagonists, to which PSB-OR-2020 belongs, interacts with an unprecedented allosteric site. [3H]PSB-OR-2020 may become a useful tool for research on P2X4 receptors and for promoting drug development.
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Affiliation(s)
- Jessica Nagel
- PharmaCenter Bonn, Pharmaceutical Institute, University of Bonn, Pharmaceutical & Medicinal Chemistry, An der Immenburg 4, Bonn, 53121, Germany
| | - Olli Törmäkangas
- Orion Pharma, Orion Corporation, Tengströminkatu 8, FI-20360 Turku, and Orionintie 1A, Espoo, FI- 02200, Finland
| | - Katja Kuokkanen
- Orion Pharma, Orion Corporation, Tengströminkatu 8, FI-20360 Turku, and Orionintie 1A, Espoo, FI- 02200, Finland
| | - Ali El-Tayeb
- PharmaCenter Bonn, Pharmaceutical Institute, University of Bonn, Pharmaceutical & Medicinal Chemistry, An der Immenburg 4, Bonn, 53121, Germany
| | - Josef Messinger
- Orion Pharma, Orion Corporation, Tengströminkatu 8, FI-20360 Turku, and Orionintie 1A, Espoo, FI- 02200, Finland
| | - Aliaa Abdelrahman
- PharmaCenter Bonn, Pharmaceutical Institute, University of Bonn, Pharmaceutical & Medicinal Chemistry, An der Immenburg 4, Bonn, 53121, Germany
| | - Christiane Bous
- PharmaCenter Bonn, Pharmaceutical Institute, University of Bonn, Pharmaceutical & Medicinal Chemistry, An der Immenburg 4, Bonn, 53121, Germany
| | - Anke C Schiedel
- PharmaCenter Bonn, Pharmaceutical Institute, University of Bonn, Pharmaceutical & Medicinal Chemistry, An der Immenburg 4, Bonn, 53121, Germany
| | - Christa E Müller
- PharmaCenter Bonn, Pharmaceutical Institute, University of Bonn, Pharmaceutical & Medicinal Chemistry, An der Immenburg 4, Bonn, 53121, Germany.
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5
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Witkin JM, Shafique H, Smith JL, Cerne R. Is there a biochemical basis for purinergic P2X3 and P2X4 receptor antagonists to be considered as anti-seizure medications? Biochem Pharmacol 2024; 222:116046. [PMID: 38341001 DOI: 10.1016/j.bcp.2024.116046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2023] [Revised: 12/15/2023] [Accepted: 02/05/2024] [Indexed: 02/12/2024]
Abstract
Patients with epilepsy require improved medications. Purinergic receptors were identified as late as 1976 and are slowly emerging as potential drug targets for the discovery of antiseizure medications. While compounds interacting with these receptors have been approved for use as medicines (e.g., gefapixant for cough) and continue to be explored for a number of diseases (e.g., pain, cancer), there have been no purinergic receptor antagonists that have been advanced for epilepsy. There are very few studies on the channel conducting receptors, P2X3 and P2X4, that suggest their possible role in seizure generation or control. However, the limited data available provides some compelling reasons to believe that they could be valuable antiseizure medication drug targets. The data implicating P2X3 and P2X4 receptors in epilepsy includes the role played by ATP in neuronal excitability and seizures, receptor localization, increased receptor expression in epileptic brain, the involvement of these receptors in seizure-associated inflammation, crosstalk between these purinergic receptors and neuronal processes involved in seizures (GABAergic and glutamatergic neurotransmission), and the significant attenuation of seizures and seizure-like activity with P2X receptor blockade. The discovery of new and selective antagonists for P2X3 and P2X4 receptors is ongoing, armed with new structural data to guide rational design. The availability of safe, brain-penetrant compounds will likely encourage the clinical exploration of epilepsy as a disease entity.
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Affiliation(s)
- Jeffrey M Witkin
- Laboratory of Antiepileptic Drug Discovery, Ascension St. Vincent, Indianapolis, IN, USA; Department of Neuroscience and Trauma Research, Ascension St. Vincent, Indianapolis, IN, USA; Department of Chemistry & Biochemistry, University of Wisconsin-Milwaukee, Milwaukee, WI, USA.
| | | | - Jodi L Smith
- Laboratory of Antiepileptic Drug Discovery, Ascension St. Vincent, Indianapolis, IN, USA
| | - Rok Cerne
- Laboratory of Antiepileptic Drug Discovery, Ascension St. Vincent, Indianapolis, IN, USA; Department of Anatomy and Cell Biology, Indiana University/Purdue University, Indianapolis, IN, USA; Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia.
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6
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Zou FL, Liu JP, Zuo C, He PF, Ye JX, Zhang WJ. The functional role of P2 purinergic receptors in the progression of gastric cancer. Purinergic Signal 2024:10.1007/s11302-024-10000-7. [PMID: 38470513 DOI: 10.1007/s11302-024-10000-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2023] [Accepted: 02/29/2024] [Indexed: 03/14/2024] Open
Abstract
Studies have confirmed that P2 purinergic receptors (P2X receptors and P2Y receptors) expressed in gastric cancer (GC) cells and GC tissues and correlates with their function. Endogenous nucleotides including ATP, ADP, UTP, and UDP, as P2 purinergic receptors activators, participate in P2 purinergic signal transduction pathway. These activated P2 purinergic receptors regulate the progression of GC mainly by mediating ion channels and intracellular signal cascades. It is worth noting that there is a difference in the expression of P2 purinergic receptors in GC, which may play different roles in the progression of GC as a tumor promoting factor or a tumor suppressor factor. Among them, P2 × 7, P2Y2 and P2Y6 receptors have certain clinical significance in patients with GC and may be used as biological molecular markers for the prediction of patients with GC. Therefore, in this paper, we discuss the functional role of nucleotide / P2 purinergic receptors signal axis in regulating the progression of GC and that these P2 purinergic receptors may be used as potential molecular targets for the prevention and treatment of GC.
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Affiliation(s)
- Fei-Long Zou
- Thyroid surgery, Shenzhen Bao'an District Songgang People's Hospital, Shenzhen City, 518105, China
| | - Ji-Peng Liu
- The Second Affiliated Hospital, Nanchang University, Nanchang City, Jiangxi Province, 343000, China
| | - Cheng Zuo
- The Second Affiliated Hospital, Nanchang University, Nanchang City, Jiangxi Province, 343000, China
| | - Peng-Fei He
- The Second Affiliated Hospital, Nanchang University, Nanchang City, Jiangxi Province, 343000, China
| | - Jin-Xiong Ye
- Thyroid surgery, Shenzhen Bao'an District Songgang People's Hospital, Shenzhen City, 518105, China.
| | - Wen-Jun Zhang
- The Second Affiliated Hospital, Nanchang University, Nanchang City, Jiangxi Province, 343000, China.
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7
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Babou Kammoe RB, Sévigny J. Extracellular nucleotides in smooth muscle contraction. Biochem Pharmacol 2024; 220:116005. [PMID: 38142836 DOI: 10.1016/j.bcp.2023.116005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Revised: 12/18/2023] [Accepted: 12/19/2023] [Indexed: 12/26/2023]
Abstract
Extracellular nucleotides and nucleosides are crucial signalling molecules, eliciting diverse biological responses in almost all organs and tissues. These molecules exert their effects by activating specific nucleotide receptors, which are finely regulated by ectonucleotidases that break down their ligands. In this comprehensive review, we aim to elucidate the relevance of extracellular nucleotides as signalling molecules in the context of smooth muscle contraction, considering the modulatory influence of ectonucleotidases on this intricate process. Specifically, we provide a detailed examination of the involvement of extracellular nucleotides in the contraction of non-vascular smooth muscles, including those found in the urinary bladder, the airways, the reproductive system, and the gastrointestinal tract. Furthermore, we present a broader overview of the role of extracellular nucleotides in vascular smooth muscle contraction.
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Affiliation(s)
- Romuald Brice Babou Kammoe
- Centre de Recherche du CHU de Québec - Université Laval, Québec City, QC G1V 4G2, Canada; Département de microbiologie-infectiologie et d'immunologie, Faculté de Médecine, Université Laval, Québec City, QC G1V 0A6, Canada
| | - Jean Sévigny
- Centre de Recherche du CHU de Québec - Université Laval, Québec City, QC G1V 4G2, Canada; Département de microbiologie-infectiologie et d'immunologie, Faculté de Médecine, Université Laval, Québec City, QC G1V 0A6, Canada.
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8
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Tewari M, Michalski S, Egan TM. Modulation of Microglial Function by ATP-Gated P2X7 Receptors: Studies in Rat, Mice and Human. Cells 2024; 13:161. [PMID: 38247852 PMCID: PMC10814008 DOI: 10.3390/cells13020161] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2023] [Revised: 01/10/2024] [Accepted: 01/12/2024] [Indexed: 01/23/2024] Open
Abstract
P2X receptors are a family of seven ATP-gated ion channels that trigger physiological and pathophysiological responses in a variety of cells. Five of the family members are sensitive to low concentrations of extracellular ATP, while the P2X6 receptor has an unknown affinity. The last subtype, the P2X7 receptor, is unique in requiring millimolar concentrations to fully activate in humans. This low sensitivity imparts the agonist with the ability to act as a damage-associated molecular pattern that triggers the innate immune response in response to the elevated levels of extracellular ATP that accompany inflammation and tissue damage. In this review, we focus on microglia because they are the primary immune cells of the central nervous system, and they activate in response to ATP or its synthetic analog, BzATP. We start by introducing purinergic receptors and then briefly consider the roles that microglia play in neurodevelopment and disease by referencing both original works and relevant reviews. Next, we move to the role of extracellular ATP and P2X receptors in initiating and/or modulating innate immunity in the central nervous system. While most of the data that we review involve work on mice and rats, we highlight human studies of P2X7R whenever possible.
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9
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Biringer RG. Migraine signaling pathways: purine metabolites that regulate migraine and predispose migraineurs to headache. Mol Cell Biochem 2023; 478:2813-2848. [PMID: 36947357 DOI: 10.1007/s11010-023-04701-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Accepted: 03/06/2023] [Indexed: 03/23/2023]
Abstract
Migraine is a debilitating disorder that afflicts over 1 billion people worldwide, involving attacks that result in a throbbing and pulsating headache. Migraine is thought to be a neurovascular event associated with vasoconstriction, vasodilation, and neuronal activation. Understanding signaling in migraine pathology is central to the development of therapeutics for migraine prophylaxis and for mitigation of migraine in the prodrome phase before pain sets in. The fact that both vasoactivity and neural sensitization are involved in migraine indicates that agonists which promote these phenomena may very well be involved in migraine pathology. One such group of agonists is the purines, in particular, adenosine phosphates and their metabolites. This manuscript explores what is known about the relationship between these metabolites and migraine pathology and explores the potential for such relationships through their known signaling pathways. Reported receptor involvement in vasoaction and nociception.
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Affiliation(s)
- Roger Gregory Biringer
- College of Osteopathic Medicine, Lake Erie College of Osteopathic Medicine, Bradenton, FL, 34211, USA.
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10
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Liu C, Cui W, Zhu K, Yuan S, Sun L, Liang Y, Lu J, Li D, Deng Z, Duan L, Zhang W, Yu X, Wang D, Zhang H. Inhibitor screening for volume-sensitive LRRC8A chloride channel. J Biomol Struct Dyn 2023:1-9. [PMID: 37902556 DOI: 10.1080/07391102.2023.2274521] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2023] [Accepted: 10/15/2023] [Indexed: 10/31/2023]
Abstract
Leucine-rich repeat-containing protein 8 A (LRRC8A) protein is a critical member of volume-regulated anion channels. It plays a critical roles in the regulation of cellular volume and involves in the development of diseases like osteoarthritis. Screening of lead compounds to modulate its function may provide potential therapeutics of related diseases. Here, we employ virtual screening techniques and molecular dynamics (MD) simulation to screen potential inhibitors against LRRC8A. LRRC8A was regarded as the drug target to investigate potential compounds from the ZINC15 database via molecular docking. The final compound was selected among the top 10 Autodock Vina score (-8.8 Kcal/mol) with the ZINC ID ZINC000018195627 after druggability prediction. The docked complex from the virtual screening was subjected to MD simulation to analyze the stability of the LRRC8A protein-ligand complex, with parameters including root mean square deviation, root mean square fluctuation and radius of gyration. Molecular Mechanics/Poisson-Boltzmann Surface Area (MM/PBSA) method was further employed to predict the binding free energies from MD simulation trajectory. Our study provides insightful analysis for the potential compound to modulate LRRC8A and lay the foundation of therapeutics development against osteoarthritis.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Chao Liu
- Department of Computer Science, School of Artificial Intelligence, Dongguan City University, Dongguan, China
- Department of Biomedical Engineering,Southern University of Science and Technology, Shenzhen, China
| | - Wenqiang Cui
- Research Center for Computer-Aided Drug Discovery, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China
| | - Kongfu Zhu
- Department of Computer Science, School of Artificial Intelligence, Dongguan City University, Dongguan, China
| | - Shuguang Yuan
- Research Center for Computer-Aided Drug Discovery, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China
| | - Liang Sun
- Shenzhen Shuli Tech Co., Ltd, Shenzhen, China
| | - Yujie Liang
- Department of Child and Adolescent Psychiatry, Shenzhen Kangning Hospital, Shenzhen Mental Health Center, Shenzhen, China
| | - Jianping Lu
- Department of Child and Adolescent Psychiatry, Shenzhen Kangning Hospital, Shenzhen Mental Health Center, Shenzhen, China
| | - Da Li
- Department of Biomedical Engineering,Southern University of Science and Technology, Shenzhen, China
| | - Zhiqin Deng
- Hand and Foot Surgery Department, Shenzhen Second People's Hospital, The First Affiliated Hospital of Shenzhen University, Shenzhen, China
| | - Li Duan
- Department of Orthopedics, Shenzhen Intelligent Orthopaedics and Biomedical Innovation Platform, Guangdong Provincial Research Center for Artificial Intelligence and Digital Orthopedic Technology, Shenzhen Second People's Hospital, The First Affiliated Hospital of Shenzhen University, Shenzhen, China
| | - Weiming Zhang
- Department of Computer Science, School of Artificial Intelligence, Dongguan City University, Dongguan, China
| | - Xiaohai Yu
- Department of Computer Science, School of Artificial Intelligence, Dongguan City University, Dongguan, China
| | - Daping Wang
- Department of Computer Science, School of Artificial Intelligence, Dongguan City University, Dongguan, China
- Department of Orthopedics, Shenzhen Intelligent Orthopaedics and Biomedical Innovation Platform, Guangdong Provincial Research Center for Artificial Intelligence and Digital Orthopedic Technology, Shenzhen Second People's Hospital, The First Affiliated Hospital of Shenzhen University, Shenzhen, China
| | - Huawei Zhang
- Department of Biomedical Engineering,Southern University of Science and Technology, Shenzhen, China
- Research Center for Computer-Aided Drug Discovery, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China
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11
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Sainz RM, Rodriguez-Quintero JH, Maldifassi MC, Stiles BM, Wennerberg E. Tumour immune escape via P2X7 receptor signalling. Front Immunol 2023; 14:1287310. [PMID: 38022596 PMCID: PMC10643160 DOI: 10.3389/fimmu.2023.1287310] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Accepted: 10/12/2023] [Indexed: 12/01/2023] Open
Abstract
While P2X7 receptor expression on tumour cells has been characterized as a promotor of cancer growth and metastasis, its expression by the host immune system is central for orchestration of both innate and adaptive immune responses against cancer. The role of P2X7R in anti-tumour immunity is complex and preclinical studies have described opposing roles of the P2X7R in regulating immune responses against tumours. Therefore, few P2X7R modulators have reached clinical testing in cancer patients. Here, we review the prognostic value of P2X7R in cancer, how P2X7R have been targeted to date in tumour models, and we discuss four aspects of how tumours skew immune responses to promote immune escape via the P2X7R; non-pore functional P2X7Rs, mono-ADP-ribosyltransferases, ectonucleotidases, and immunoregulatory cells. Lastly, we discuss alternative approaches to offset tumour immune escape via P2X7R to enhance immunotherapeutic strategies in cancer patients.
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Affiliation(s)
- Ricardo M. Sainz
- Division of Radiotherapy and Imaging, The Institute of Cancer Research, London, United Kingdom
| | - Jorge Humberto Rodriguez-Quintero
- Department of Cardiovascular and Thoracic Surgery, Albert Einstein College of Medicine, Montefiore Health System, Bronx, NY, United States
| | - Maria Constanza Maldifassi
- Department of Cardiovascular and Thoracic Surgery, Albert Einstein College of Medicine, Montefiore Health System, Bronx, NY, United States
| | - Brendon M. Stiles
- Department of Cardiovascular and Thoracic Surgery, Albert Einstein College of Medicine, Montefiore Health System, Bronx, NY, United States
| | - Erik Wennerberg
- Division of Radiotherapy and Imaging, The Institute of Cancer Research, London, United Kingdom
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12
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Schulman ES, Nishi H, Pelleg A. Degranulation of human mast cells: modulation by P2 receptors' agonists. Front Immunol 2023; 14:1216580. [PMID: 37868982 PMCID: PMC10585249 DOI: 10.3389/fimmu.2023.1216580] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Accepted: 09/04/2023] [Indexed: 10/24/2023] Open
Abstract
Since the late 1970s, there has been an alarming increase in the incidence of asthma and its morbidity and mortality. Acute obstruction and inflammation of allergic asthmatic airways are frequently caused by inhalation of exogenous substances such as allergens cross-linking IgE receptors expressed on the surface of the human lung mast cells (HLMC). The degree of constriction of human airways produced by identical amounts of inhaled allergens may vary from day to day and even hour to hour. Endogenous factors in the human mast cell (HMC)'s microenvironment during allergen exposure may markedly modulate the degranulation response. An increase in allergic responsiveness may significantly enhance bronchoconstriction and breathlessness. This review focuses on the role that the ubiquitous endogenous purine nucleotide, extracellular adenosine 5'-triphosphate (ATP), which is a component of the damage-associated molecular patterns, plays in mast cells' physiology. ATP activates P2 purinergic cell-surface receptors (P2R) to trigger signaling cascades resulting in heightened inflammatory responses. ATP is the most potent enhancer of IgE-mediated HLMC degranulation described to date. Current knowledge of ATP as it relates to targeted receptor(s) on HMC along with most recent studies exploring HMC post-receptor activation pathways are discussed. In addition, the reviewed studies may explain why brief, minimal exposures to allergens (e.g., dust, cat, mouse, and grass) can unpredictably lead to intense clinical reactions. Furthermore, potential therapeutic approaches targeting ATP-related enhancement of allergic reactions are presented.
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Affiliation(s)
- Edward S. Schulman
- Division of Pulmonary, Critical Care and Allergy, Drexel University College of Medicine, Philadelphia, PA, United States
| | - Haruhisa Nishi
- Department of Pharmacology, Jikei University School of Medicine, Tokyo, Japan
| | - Amir Pelleg
- Danmir Therapeutics, LLC, Haverford, PA, United States
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13
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Luo HM, Ye JR, Pu FQ, Luo HL, Zhang WJ. Role and therapeutic target of P2X2/3 receptors in visceral pain. Neuropeptides 2023; 101:102355. [PMID: 37390743 DOI: 10.1016/j.npep.2023.102355] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/12/2023] [Revised: 06/19/2023] [Accepted: 06/21/2023] [Indexed: 07/02/2023]
Abstract
Visceral pain (VP) is caused by internal organ disease. VP is involved in nerve conduction and related signaling molecules, but its specific pathogenesis has not yet been fully elucidated. Currently, there are no effective methods for treating VP. The role of P2X2/3 in VP has progressed. After visceral organs are subjected to noxious stimulation, cells release ATP, activate P2X2/3, enhance the sensitivity of peripheral receptors and the plasticity of neurons, enhance sensory information transmission, sensitize the central nervous system, and play an important role in the development of VP. However, antagonists possess the pharmacological effect of relieving pain. Therefore, in this review, we summarize the biological functions of P2X2/3 and discuss the intrinsic link between P2X2/3 and VP. Moreover, we focus on the pharmacological effects of P2X2/3 antagonists on VP therapy and provide a theoretical basis for its targeted therapy.
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Affiliation(s)
- Hong-Mei Luo
- Department of Rheumatology, The Affiliated Hospital of Jiangxi University of Chinese Medicine, Nanchang City, Jiangxi province 343000, China
| | - Jia-Rong Ye
- Department of Gastrointestinal surgery, The Second Affiliated Hospital, Nanchang University, Nanchang City, Jiangxi province 343000, China
| | - Fan-Qin Pu
- Department of Rheumatology, The Affiliated Hospital of Jiangxi University of Chinese Medicine, Nanchang City, Jiangxi province 343000, China
| | - Hong-Liang Luo
- Department of Rehabilitation Medicine, The Second Affiliated Hospital, Nanchang University, Nanchang City, Jiangxi province 343000, China
| | - Wen-Jun Zhang
- Department of Rehabilitation Medicine, The Second Affiliated Hospital, Nanchang University, Nanchang City, Jiangxi province 343000, China.
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14
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Ledderose S, Rodler S, Eismann L, Ledderose G, Rudelius M, Junger WG, Ledderose C. P2X1 and P2X7 Receptor Overexpression Is a Negative Predictor of Survival in Muscle-Invasive Bladder Cancer. Cancers (Basel) 2023; 15:2321. [PMID: 37190249 PMCID: PMC10136747 DOI: 10.3390/cancers15082321] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Revised: 04/10/2023] [Accepted: 04/14/2023] [Indexed: 05/17/2023] Open
Abstract
Bladder cancer is amongst the most common causes of cancer death worldwide. Muscle-invasive bladder cancer (MIBC) bears a particularly poor prognosis. Overexpression of purinergic P2X receptors (P2XRs) has been associated with worse outcome in several malignant tumors. Here, we investigated the role of P2XRs in bladder cancer cell proliferation in vitro and the prognostic value of P2XR expression in MIBC patients. Cell culture experiments with T24, RT4, and non-transformed TRT-HU-1 cells revealed a link between high ATP concentrations in the cell culture supernatants of bladder cell lines and a higher grade of malignancy. Furthermore, proliferation of highly malignant T24 bladder cancer cells depended on autocrine signaling through P2X receptors. P2X1R, P2X4R, and P2X7R expression was immunohistochemically analyzed in tumor specimens from 173 patients with MIBC. High P2X1R expression was associated with pathological parameters of disease progression and reduced survival time. High combined expression of P2X1R and P2X7R increased the risk of distant metastasis and was an independent negative predictor of overall and tumor-specific survival in multivariate analyses. Our results suggest that P2X1R/P2X7R expression scores are powerful negative prognostic markers in MIBC patients and that P2XR-mediated pathways are potential targets for novel therapeutic strategies in bladder cancer.
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Affiliation(s)
- Stephan Ledderose
- Institute of Pathology, Ludwig Maximilian University, 80337 Munich, Germany
| | - Severin Rodler
- Department of Urology, Ludwig Maximilian University, 81377 Munich, Germany
| | - Lennert Eismann
- Department of Urology, Ludwig Maximilian University, 81377 Munich, Germany
| | - Georg Ledderose
- Department of Oto-Rhino-Laryngology, Ludwig Maximilian University, 81377 Munich, Germany
| | - Martina Rudelius
- Institute of Pathology, Ludwig Maximilian University, 80337 Munich, Germany
| | - Wolfgang G. Junger
- Department of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
- Department of Surgery, University of California San Diego Health, La Jolla, CA 92037, USA
| | - Carola Ledderose
- Department of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
- Department of Surgery, University of California San Diego Health, La Jolla, CA 92037, USA
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15
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Abstract
Within the family of purinergic receptors, the P2X1 receptor is a ligand-gated ion channel that plays a role in urogenital, immune and cardiovascular function. Specifically, the P2X1 receptor has been implicated in controlling smooth muscle contractions of the vas deferens and therefore has emerged as an exciting drug target for male contraception. In addition, the P2X1 receptor contributes to smooth muscle contractions of the bladder and is a target to treat bladder dysfunction. Finally, platelets and neutrophils have populations of P2X1 receptors that could be targeted for thrombosis and inflammatory conditions. Drugs that specifically target the P2X1 receptor have been challenging to develop, and only recently have small molecule antagonists of the P2X1 receptor been available. However, these ligands need further biological validation for appropriate selectivity and drug-like properties before they will be suitable for use in preclinical models of disease. Although the atomic structure of the P2X1 receptor has yet to be determined, the recent discovery of several other P2X receptor structures and improvements in the field of structural biology suggests that this is now a distinct possibility. Such efforts may significantly improve drug discovery efforts at the P2X1 receptor.
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16
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An Q, Yue G, Yang X, Lou J, Shan W, Ding J, Jin Z, Hu Y, Du Q, Liao Q, Xie R, Xu J. Pathophysiological Role of Purinergic P2X Receptors in Digestive System Diseases. Front Physiol 2022; 12:781069. [PMID: 35002763 PMCID: PMC8740087 DOI: 10.3389/fphys.2021.781069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Accepted: 12/01/2021] [Indexed: 11/16/2022] Open
Abstract
P2X receptors (P2XRs) are trimeric, non-selective cation channels activated by extracellular ATP and widely distributed in the digestive system. P2XRs have an important role in the physiological function of the digestive system, such as neurotransmission, ion transports, proliferation and apoptosis, muscle contraction, and relaxation. P2XRs can be involved in pain mechanisms both centrally and in the periphery and confirmed the association of P2XRs with visceral pain. In the periphery, ATP can be released as a result of tissue injury, visceral distension, or sympathetic activation and can excite nociceptive primary afferents by acting at homomeric P2X(3)R or heteromeric P2X(2/3)R. Thus, peripheral P2XRs, and homomeric P2X(3) and/or heteromeric P2X(2/3)R in particular, constitute attractive targets for analgesic drugs. Recently studies have shown that P2XRs have made significant advances in inflammation and cancer. P2X7R mediates NLRP3 inflammasome activation, cytokine and chemokine release, T lymphocyte survival and differentiation, transcription factor activation, and cell death. The P2X7R is a potent stimulant of inflammation and immunity and a promoter of cancer cell growth. This makes P2X7R an appealing target for anti-inflammatory and anti-cancer therapy. It is believed that with the further study of P2XRs and its subtypes, P2XRs and its specific antagonists will be expected to be widely used in the treatment of human digestive diseases in the future.
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Affiliation(s)
- Qimin An
- Department of Gastroenterology, Affiliated Hospital of Zunyi Medical University, Zunyi, China.,The Collaborative Innovation Center of Tissue Damage Repair and Regeneration Medicine of Zunyi Medical University, Zunyi, China
| | - Gengyu Yue
- Department of Gastroenterology, Affiliated Hospital of Zunyi Medical University, Zunyi, China.,The Collaborative Innovation Center of Tissue Damage Repair and Regeneration Medicine of Zunyi Medical University, Zunyi, China
| | - Xiaoxu Yang
- Department of Gastroenterology, Affiliated Hospital of Zunyi Medical University, Zunyi, China.,The Collaborative Innovation Center of Tissue Damage Repair and Regeneration Medicine of Zunyi Medical University, Zunyi, China
| | - Jun Lou
- Department of Gastroenterology, Affiliated Hospital of Zunyi Medical University, Zunyi, China.,The Collaborative Innovation Center of Tissue Damage Repair and Regeneration Medicine of Zunyi Medical University, Zunyi, China
| | - Weixi Shan
- Department of Gastroenterology, Affiliated Hospital of Zunyi Medical University, Zunyi, China.,The Collaborative Innovation Center of Tissue Damage Repair and Regeneration Medicine of Zunyi Medical University, Zunyi, China
| | - Jianhong Ding
- Department of Gastroenterology, Affiliated Hospital of Zunyi Medical University, Zunyi, China.,The Collaborative Innovation Center of Tissue Damage Repair and Regeneration Medicine of Zunyi Medical University, Zunyi, China
| | - Zhe Jin
- Department of Gastroenterology, Affiliated Hospital of Zunyi Medical University, Zunyi, China.,The Collaborative Innovation Center of Tissue Damage Repair and Regeneration Medicine of Zunyi Medical University, Zunyi, China
| | - Yanxia Hu
- Department of Gastroenterology, Affiliated Hospital of Zunyi Medical University, Zunyi, China.,The Collaborative Innovation Center of Tissue Damage Repair and Regeneration Medicine of Zunyi Medical University, Zunyi, China
| | - Qian Du
- Department of Gastroenterology, Affiliated Hospital of Zunyi Medical University, Zunyi, China.,The Collaborative Innovation Center of Tissue Damage Repair and Regeneration Medicine of Zunyi Medical University, Zunyi, China
| | - Qiushi Liao
- Department of Gastroenterology, Affiliated Hospital of Zunyi Medical University, Zunyi, China.,The Collaborative Innovation Center of Tissue Damage Repair and Regeneration Medicine of Zunyi Medical University, Zunyi, China
| | - Rui Xie
- Department of Gastroenterology, Affiliated Hospital of Zunyi Medical University, Zunyi, China.,The Collaborative Innovation Center of Tissue Damage Repair and Regeneration Medicine of Zunyi Medical University, Zunyi, China
| | - Jingyu Xu
- Department of Gastroenterology, Affiliated Hospital of Zunyi Medical University, Zunyi, China.,The Collaborative Innovation Center of Tissue Damage Repair and Regeneration Medicine of Zunyi Medical University, Zunyi, China
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17
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Salcman B, Affleck K, Bulfone-Paus S. P2X Receptor-Dependent Modulation of Mast Cell and Glial Cell Activities in Neuroinflammation. Cells 2021; 10:cells10092282. [PMID: 34571930 PMCID: PMC8471135 DOI: 10.3390/cells10092282] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Revised: 08/23/2021] [Accepted: 08/30/2021] [Indexed: 11/27/2022] Open
Abstract
Localisation of mast cells (MCs) at the abluminal side of blood vessels in the brain favours their interaction with glial cells, neurons, and endothelial cells, resulting in the activation of these cells and the release of pro-inflammatory mediators. In turn, stimulation of glial cells, such as microglia, astrocytes, and oligodendrocytes may result in the modulation of MC activities. MCs, microglia, astrocytes, and oligodendrocytes all express P2X receptors (P2XRs) family members that are selectively engaged by ATP. As increased concentrations of extracellular adenosine 5′-triphosphate (ATP) are present in the brain in neuropathological conditions, P2XR activation in MCs and glial cells contributes to the control of their communication and amplification of the inflammatory response. In this review we discuss P2XR-mediated MC activation, its bi-directional effect on microglia, astrocytes and oligodendrocytes and role in neuroinflammation.
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Affiliation(s)
- Barbora Salcman
- Lydia Becker Institute of Immunology and Inflammation, Manchester Collaborative Centre for Inflammation Research, University of Manchester, Manchester M13 9NT, UK;
| | - Karen Affleck
- GlaxoSmithKline, Immunology Research Unit, Stevenage SG1 2NY, UK;
| | - Silvia Bulfone-Paus
- Lydia Becker Institute of Immunology and Inflammation, Manchester Collaborative Centre for Inflammation Research, University of Manchester, Manchester M13 9NT, UK;
- Correspondence:
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18
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Rabelo ILA, Arnaud-Sampaio VF, Adinolfi E, Ulrich H, Lameu C. Cancer Metabostemness and Metabolic Reprogramming via P2X7 Receptor. Cells 2021; 10:1782. [PMID: 34359950 PMCID: PMC8305434 DOI: 10.3390/cells10071782] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Revised: 06/25/2021] [Accepted: 06/27/2021] [Indexed: 12/17/2022] Open
Abstract
The heterogeneity of tumor cell mass and the plasticity of cancer cell phenotypes in solid tumors allow for the insurgence of resistant and metastatic cells, responsible for cancer patients' clinical management's main challenges. Among several factors that are responsible for increased cancer aggression, metabolic reprogramming is recently emerging as an ultimate cancer hallmark, as it is central for cancer cell survival and self-renewal, metastasis and chemoresistance. The P2X7 receptor, whose expression is upregulated in many solid and hematological malignancies, is also emerging as a good candidate in cancer metabolic reprogramming and the regulation of stem cell proliferation and differentiation. Metabostemness refers to the metabolic reprogramming of cancer cells toward less differentiated (CSCs) cellular states, and we believe that there is a strong correlation between metabostemness and P2X7 receptor functions in oncogenic processes. Here, we summarize important aspects of P2X7 receptor functions in normal and tumor tissues as well as essential aspects of its structure, regulation, pharmacology and its clinical use. Finally, we review current knowledge implicating P2X7 receptor functions in cancer-related molecular pathways, in metabolic reprogramming and in metabostemness.
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Affiliation(s)
- Izadora Lorrany Alves Rabelo
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo 05508-000, Brazil; (I.L.A.R.); (V.F.A.-S.); (H.U.)
| | - Vanessa Fernandes Arnaud-Sampaio
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo 05508-000, Brazil; (I.L.A.R.); (V.F.A.-S.); (H.U.)
| | - Elena Adinolfi
- Department of Medical Sciences, Section of Experimental Medicine, University of Ferrara, 44121 Ferrara, Italy;
| | - Henning Ulrich
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo 05508-000, Brazil; (I.L.A.R.); (V.F.A.-S.); (H.U.)
| | - Claudiana Lameu
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo 05508-000, Brazil; (I.L.A.R.); (V.F.A.-S.); (H.U.)
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19
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Unwin RJ. Purinergic signalling in the kidney - A beginning with Geoffrey Burnstock. Auton Neurosci 2021; 234:102833. [PMID: 34118763 DOI: 10.1016/j.autneu.2021.102833] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Revised: 05/29/2021] [Accepted: 06/02/2021] [Indexed: 11/24/2022]
Abstract
This not an original publication or a current and up-to-date review of purinergic signalling and kidney function, but rather a tribute to Professor Geoffrey Burnstock, written as a short and personal memoir of our early collaborative work together on this topic: our beginnings and the subsequent journey we took with our many valued collaborators along the way.
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Affiliation(s)
- Robert J Unwin
- Department of Renal Medicine, University College London, UK.
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20
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The P2X7 Receptor in the Maintenance of Cancer Stem Cells, Chemoresistance and Metastasis. Stem Cell Rev Rep 2021; 16:288-300. [PMID: 31813120 DOI: 10.1007/s12015-019-09936-w] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Metastasis is the worst prognosis predictor in the clinical course of cancer development. Features of metastatic cancer cells include migratory ability, low degree of differentiation, self-renewal and proliferation potentials, as well as resistance to therapies. Metastatic cells do not present all of the necessary characteristics at once. Indeed, they have a unique phenotypic plasticity, allowing the acquisition of features that make them successful in all steps of metastasis. Cancer stem cells (CSC), the most undifferentiated cells in the tumor mass, display highest metastatic potential and resistance to radio- and chemotherapy. Growing tumors exhibit marked upregulation of P2X7 receptor expression and secrete ATP. Since the P2X7 receptor plays an important role in the maintenance of undifferentiated state of pluripotent cells, its importance on cell fate regulation in the tumor mass is suggested. Considering the extensive crosstalk between CSCs, epithelial-mesenchymal transition, drug resistance and metastasis, current knowledge implicating P2X7 receptor function in these phenomena and new avenues for therapeutic strategies to control metastasis are reviewed.
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21
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Dissection of P2X4 and P2X7 Receptor Current Components in BV-2 Microglia. Int J Mol Sci 2020; 21:ijms21228489. [PMID: 33187309 PMCID: PMC7696836 DOI: 10.3390/ijms21228489] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Revised: 11/09/2020] [Accepted: 11/09/2020] [Indexed: 12/21/2022] Open
Abstract
Microglia cells represent the immune system of the central nervous system. They become activated by ATP released from damaged and inflamed tissue via purinergic receptors. Ionotropic purinergic P2X4 and P2X7 receptors have been shown to be involved in neurological inflammation and pain sensation. Whether the two receptors assemble exclusively as homotrimers or also as heterotrimers is still a matter of debate. We investigated the expression of P2X receptors in BV-2 microglia cells applying the whole-cell voltage-clamp technique. We dissected P2X4 and P2X7 receptor-mediated current components by using specific P2X4 and P2X7 receptor blockers and by their characteristic current kinetics. We found that P2X4 and P2X7 receptors are activated independently from each other, indicating that P2X4/P2X7 heteromers are not of functional significance in these cells. The pro-inflammatory mediators lipopolysaccharide and interferon γ, if applied in combination, upregulated P2X4, but not P2X7 receptor-dependent current components also arguing against phenotypically relevant heteromerization of P2X4 and P2X7 receptor subunits.
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22
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Purinergic signaling orchestrating neuron-glia communication. Pharmacol Res 2020; 162:105253. [PMID: 33080321 DOI: 10.1016/j.phrs.2020.105253] [Citation(s) in RCA: 50] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Revised: 09/29/2020] [Accepted: 10/09/2020] [Indexed: 12/12/2022]
Abstract
This review discusses the evidence supporting a role for ATP signaling (operated by P2X and P2Y receptors) and adenosine signaling (mainly operated by A1 and A2A receptors) in the crosstalk between neurons, astrocytes, microglia and oligodendrocytes. An initial emphasis will be given to the cooperation between adenosine receptors to sharpen information salience encoding across synapses. The interplay between ATP and adenosine signaling in the communication between astrocytes and neurons will then be presented in context of the integrative properties of the astrocytic syncytium, allowing to implement heterosynaptic depression processes in neuronal networks. The process of microglia 'activation' and its control by astrocytes and neurons will then be analyzed under the perspective of an interplay between different P2 receptors and adenosine A2A receptors. In spite of these indications of a prominent role of purinergic signaling in the bidirectional communication between neurons and glia, its therapeutical exploitation still awaits obtaining an integrated view of the spatio-temporal action of ATP signaling and adenosine signaling, clearly distinguishing the involvement of both purinergic signaling systems in the regulation of physiological processes and in the control of pathogenic-like responses upon brain dysfunction or damage.
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23
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Alberto AVP, da Silva Ferreira NC, Soares RF, Alves LA. Molecular Modeling Applied to the Discovery of New Lead Compounds for P2 Receptors Based on Natural Sources. Front Pharmacol 2020; 11:01221. [PMID: 33117147 PMCID: PMC7553047 DOI: 10.3389/fphar.2020.01221] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Accepted: 07/27/2020] [Indexed: 12/24/2022] Open
Abstract
P2 receptors are a family of transmembrane receptors activated by nucleotides and nucleosides. Two classes have been described in mammals, P2X and P2Y, which are implicated in various diseases. Currently, only P2Y12 has medicines approved for clinical use as antiplatelet agents and natural products have emerged as a source of new drugs with action on P2 receptors due to the diversity of chemical structures. In drug discovery, in silico virtual screening (VS) techniques have become popular because they have numerous advantages, which include the evaluation of thousands of molecules against a target, usually proteins, faster and cheaper than classical high throughput screening (HTS). The number of studies using VS techniques has been growing in recent years and has led to the discovery of new molecules of natural origin with action on different P2X and P2Y receptors. Using different algorithms it is possible to obtain information on absorption, distribution, metabolism, toxicity, as well as predictions on biological activity and the lead-likeness of the selected hits. Selected biomolecules may then be tested by molecular dynamics and, if necessary, rationally designed or modified to improve their interaction for the target. The algorithms of these in silico tools are being improved to permit the precision development of new drugs and, in the future, this process will take the front of drug development against some central nervous system (CNS) disorders. Therefore, this review discusses the methodologies of in silico tools concerning P2 receptors, as well as future perspectives and discoveries, such as the employment of artificial intelligence in drug discovery.
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Affiliation(s)
- Anael Viana Pinto Alberto
- Laboratory of Cellular Communication, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil
| | | | - Rafael Ferreira Soares
- Laboratory of Functional Genomics and Bioinformatics, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil
| | - Luiz Anastacio Alves
- Laboratory of Cellular Communication, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil
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24
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Resolving the Ionotropic P2X4 Receptor Mystery Points Towards a New Therapeutic Target for Cardiovascular Diseases. Int J Mol Sci 2020; 21:ijms21145005. [PMID: 32679900 PMCID: PMC7404342 DOI: 10.3390/ijms21145005] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 07/09/2020] [Accepted: 07/13/2020] [Indexed: 12/18/2022] Open
Abstract
Adenosine triphosphate (ATP) is a primordial versatile autacoid that changes its role from an intracellular energy saver to a signaling molecule once released to the extracellular milieu. Extracellular ATP and its adenosine metabolite are the main activators of the P2 and P1 purinoceptor families, respectively. Mounting evidence suggests that the ionotropic P2X4 receptor (P2X4R) plays pivotal roles in the regulation of the cardiovascular system, yet further therapeutic advances have been hampered by the lack of selective P2X4R agonists. In this review, we provide the state of the art of the P2X4R activity in the cardiovascular system. We also discuss the role of P2X4R activation in kidney and lungs vis a vis their interplay to control cardiovascular functions and dysfunctions, including putative adverse effects emerging from P2X4R activation. Gathering this information may prompt further development of selective P2X4R agonists and its translation to the clinical practice.
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25
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Microglia Purinoceptor P2Y6: An Emerging Therapeutic Target in CNS Diseases. Cells 2020; 9:cells9071595. [PMID: 32630251 PMCID: PMC7407337 DOI: 10.3390/cells9071595] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Revised: 06/24/2020] [Accepted: 06/29/2020] [Indexed: 12/14/2022] Open
Abstract
The purinergic receptor P2Y6 is expressed in immune cells, including the microglia that are implicated in neurological disorders. Its ligand, UDP, is a signaling molecule that can serve as an “find-me” signal when released in significant quantities by damaged/dying cells. The binding of UDP by P2Y6R leads to the activation of different biochemical pathways, depending on the disease context and the pathological environment. Generally, P2Y6R stimulates phagocytosis. However, whether or not phagocytosis coincides with cell activation or the secretion of pro-inflammatory cytokines needs further investigation. The current review aims to discuss the various functions of P2Y6R in some CNS disorders. We present evidence that P2Y6R may have a detrimental or beneficial role in the nervous system, in the context of neurological pathologies, such as ischemic stroke, Alzheimer’s disease, Parkinson’s disease, radiation-induced brain injury, and neuropathic pain.
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26
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Estrada JA, Ducrocq GP, Kim JS, Kaufman MP. Intrathecal injection of brilliant blue G, a P2X7 antagonist, attenuates the exercise pressor reflex in rats. Am J Physiol Regul Integr Comp Physiol 2020; 319:R223-R232. [PMID: 32609538 DOI: 10.1152/ajpregu.00093.2020] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Purinergic 2X (P2X) receptors on the endings of group III and IV afferents play a role in evoking the exercise pressor reflex. Particular attention has been paid to P2X3 receptors because their blockade in the periphery attenuated this reflex. In contrast, nothing is known about the role played by P2X receptors in the spinal cord in evoking the exercise pressor reflex in rats. P2X7 receptors, in particular, may be especially important in this regard because they are found in abundance on spinal glial cells and may communicate with neurons to effect reflexes controlling cardiovascular function. Consequently, we investigated the role played by spinal P2X7 receptors in evoking the exercise pressor reflex in decerebrated rats. We found that intrathecal injection of the P2X7 antagonist brilliant blue G (BBG) attenuated the exercise pressor reflex (blood pressure index: 294 ± 112 mmHg·s before vs. 7 ± 32 mmHg·s after; P < 0.05). Likewise, intrathecal injection of minocycline, which inhibits microglial cell output, attenuated the reflex. In contrast, intrathecal injection of BBG did not attenuate the pressor response evoked by intracarotid injection of sodium cyanide, a maneuver that stimulated carotid chemoreceptors. Moreover, injections of BBG either into the arterial supply of the contracting hindlimb muscles or into the jugular vein did not attenuate the exercise pressor reflex. Our findings support the hypothesis that P2X7 receptors on microglial cells within the spinal cord play a role in evoking the exercise pressor reflex.
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Affiliation(s)
- Juan A Estrada
- Heart and Vascular Institute, Penn State College of Medicine, Hershey, Pennsylvania
| | - Guillaume P Ducrocq
- Heart and Vascular Institute, Penn State College of Medicine, Hershey, Pennsylvania
| | - Joyce S Kim
- Heart and Vascular Institute, Penn State College of Medicine, Hershey, Pennsylvania
| | - Marc P Kaufman
- Heart and Vascular Institute, Penn State College of Medicine, Hershey, Pennsylvania
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27
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Corciulo C, Cronstein BN. Signaling of the Purinergic System in the Joint. Front Pharmacol 2020; 10:1591. [PMID: 32038258 PMCID: PMC6993121 DOI: 10.3389/fphar.2019.01591] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Accepted: 12/09/2019] [Indexed: 12/15/2022] Open
Abstract
The joint is a complex anatomical structure consisting of different tissues, each with a particular feature, playing together to give mobility and stability at the body. All the joints have a similar composition including cartilage for reducing the friction of the movement and protecting the underlying bone, a synovial membrane that produces synovial fluid to lubricate the joint, ligaments to limit joint movement, and tendons for the interaction with muscles. Direct or indirect damage of one or more of the tissues forming the joint is the foundation of different pathological conditions. Many molecular mechanisms are involved in maintaining the joint homeostasis as well as in triggering disease development. The molecular pathway activated by the purinergic system is one of them.The purinergic signaling defines a group of receptors and intermembrane channels activated by adenosine, adenosine diphosphate, adenosine 5’-triphosphate, uridine triphosphate, and uridine diphosphate. It has been largely described as a modulator of many physiological and pathological conditions including rheumatic diseases. Here we will give an overview of the purinergic system in the joint describing its expression and function in the synovium, cartilage, ligament, tendon, and bone with a therapeutic perspective.
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Affiliation(s)
- Carmen Corciulo
- Division of Translational Medicine, Department of Medicine, NYU School of Medicine, New York, NY, United States.,Krefting Research Centre-Department of Internal Medicine and Clinical Nutrition, Institute of Medicine, University of Gothenburg, Gothenburg, Sweden
| | - Bruce N Cronstein
- Division of Translational Medicine, Department of Medicine, NYU School of Medicine, New York, NY, United States.,Division of Rheumatology, Department of Medicine, NYU School of Medicine, New York, NY, United States
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28
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Sun LF, Liu Y, Wang J, Huang LD, Yang Y, Cheng XY, Fan YZ, Zhu MX, Liang H, Tian Y, Wang HS, Guo CR, Yu Y. Altered allostery of the left flipper domain underlies the weak ATP response of rat P2X5 receptors. J Biol Chem 2019; 294:19589-19603. [PMID: 31727741 PMCID: PMC6926468 DOI: 10.1074/jbc.ra119.009959] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Revised: 11/12/2019] [Indexed: 12/31/2022] Open
Abstract
Although the extracellular ATP-gated cation channel purinergic receptor P2X5 is widely expressed in heart, skeletal muscle, and immune and nervous systems in mammals, little is known about its functions and channel-gating activities. This lack of knowledge is due to P2X5's weak ATP responses in several mammalian species, such as humans, rats, and mice. WT human P2X5 (hP2X5Δ328-349) does not respond to ATP, whereas a full-length variant, hP2X5 (hP2X5-FL), containing exon 10 encoding the second hP2X5 transmembrane domain (TM2), does. However, although rat P2X5 (rP2X5) has a full-length TM2, ATP induces only weak currents in rP2X5, which prompted us to investigate the mechanism underlying this small ATP response. Here, we show that single replacements of specific rP2X5 residues with the corresponding residues in hP2X5 (S191F or F195H) significantly enhance the current amplitude of rP2X5. Using a combination of engineered disulfide cross-linking, single-channel recording, and molecular modeling, we interrogated the effects of S191F and F195H substitutions on the allostery of the left flipper (LF) domain. On the basis of our findings, we propose that the bound ATP-induced distinct allostery of the LF domain with that of other functional subtypes has caused the weak ATP response of rP2X5 receptors. The findings of our study provide the prerequisite for future transgenic studies on the physiological and pathological functions of P2X5 receptors.
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Affiliation(s)
- Liang-Fei Sun
- Institute of Medical Sciences and Department of Pharmacology and Physiology, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Yan Liu
- Institute of Medical Sciences and Department of Pharmacology and Physiology, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Jin Wang
- Institute of Medical Sciences and Department of Pharmacology and Physiology, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Li-Dong Huang
- Institute of Medical Sciences and Department of Pharmacology and Physiology, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Yang Yang
- Institute of Medical Sciences and Department of Pharmacology and Physiology, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Xiao-Yang Cheng
- Institute of Medical Sciences and Department of Pharmacology and Physiology, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Ying-Zhe Fan
- Putuo District Center Hospital, Shanghai University of Chinese Traditional Medicine, Shanghai 200026, China
| | - Michael X Zhu
- Department of Integrative Biology and Pharmacology, McGovern Medical School, University of Texas Health Science Center, Houston, Texas 77030
| | - Hong Liang
- State Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources, School of Chemistry and Pharmacy, Guangxi Normal University, Guilin 541004, China
| | - Yun Tian
- College of Bioscience and Biotechnology, Hunan Agricultural University, Changsha 410128, China
| | - Heng-Shan Wang
- State Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources, School of Chemistry and Pharmacy, Guangxi Normal University, Guilin 541004, China
| | - Chang-Run Guo
- Department of Basic Medicine and Clinical Pharmacy, China Pharmaceutical University, Nanjing 210009, China
| | - Ye Yu
- Institute of Medical Sciences and Department of Pharmacology and Physiology, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
- College of Bioscience and Biotechnology, Hunan Agricultural University, Changsha 410128, China
- Department of Basic Medicine and Clinical Pharmacy, China Pharmaceutical University, Nanjing 210009, China
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29
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Hearing loss mutations alter the functional properties of human P2X2 receptor channels through distinct mechanisms. Proc Natl Acad Sci U S A 2019; 116:22862-22871. [PMID: 31636190 DOI: 10.1073/pnas.1912156116] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Activation of P2X2 receptor channels by extracellular ATP is thought to play important roles in cochlear adaptation to elevated sound levels and protection from overstimulation. Each subunit of a trimeric P2X2 receptor is composed of intracellular N and C termini, a large extracellular domain containing the ATP binding site and 2 transmembrane helices (TM1 and TM2) that form a cation permeable pore. Whole-exome sequencing and linkage analysis have identified 3 hP2X2 receptor mutations (V60L, D273Y, and G353R) that cause dominantly inherited progressive sensorineural hearing loss (DFNA41). Available structures of related P2X receptors suggest that these 3 mutations localize to TM1 (V60L), TM2 (G353R), or the β-sheet linking the TMs to the extracellular ATP binding sites (D273Y). Previous studies have concluded that the V60L and G353R mutants are nonfunctional, whereas the D273Y mutant has yet to be studied. Here, we demonstrate that both V60L and G353R mutations do form functional channels, whereas the D273Y mutation prevents the expression of functional channels on the cell membrane. Our results show that the V60L mutant forms constitutively active channels that are insensitive to ATP or the antagonist suramin, suggesting uncoupling of the pore and the ligand binding domains. In contrast, the G353R mutant can be activated by ATP but exhibits alterations in sensitivity to ATP, inward rectification, and ion selectivity. Collectively, our results demonstrate that the loss of functional P2X2 receptors or distinct alterations of its functional properties lead to noise-induced hearing loss, highlighting the importance of these channels in preserving hearing.
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30
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Kopp R, Krautloher A, Ramírez-Fernández A, Nicke A. P2X7 Interactions and Signaling - Making Head or Tail of It. Front Mol Neurosci 2019; 12:183. [PMID: 31440138 PMCID: PMC6693442 DOI: 10.3389/fnmol.2019.00183] [Citation(s) in RCA: 156] [Impact Index Per Article: 31.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Accepted: 07/11/2019] [Indexed: 12/14/2022] Open
Abstract
Extracellular adenine nucleotides play important roles in cell-cell communication and tissue homeostasis. High concentrations of extracellular ATP released by dying cells are sensed as a danger signal by the P2X7 receptor, a non-specific cation channel. Studies in P2X7 knockout mice and numerous disease models have demonstrated an important role of this receptor in inflammatory processes. P2X7 activation has been shown to induce a variety of cellular responses that are not usually associated with ion channel function, for example changes in the plasma membrane composition and morphology, ectodomain shedding, activation of lipases, kinases, and transcription factors, as well as cytokine release and apoptosis. In contrast to all other P2X family members, the P2X7 receptor contains a long intracellular C-terminus that constitutes 40% of the whole protein and is considered essential for most of these effects. So far, over 50 different proteins have been identified to physically interact with the P2X7 receptor. However, few of these interactions have been confirmed in independent studies and for the majority of these proteins, the interaction domains and the physiological consequences of the interactions are only poorly described. Also, while the structure of the P2X7 extracellular domain has recently been resolved, information about the organization and structure of its C-terminal tail remains elusive. After shortly describing the structure and assembly of the P2X7 receptor, this review gives an update of the identified or proposed interaction domains within the P2X7 C-terminus, describes signaling pathways in which this receptor has been involved, and provides an overlook of the identified interaction partners.
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Affiliation(s)
- Robin Kopp
- Walther Straub Institute of Pharmacology and Toxicology, Faculty of Medicine, LMU Munich, Munich, Germany
| | - Anna Krautloher
- Walther Straub Institute of Pharmacology and Toxicology, Faculty of Medicine, LMU Munich, Munich, Germany
| | - Antonio Ramírez-Fernández
- Walther Straub Institute of Pharmacology and Toxicology, Faculty of Medicine, LMU Munich, Munich, Germany
| | - Annette Nicke
- Walther Straub Institute of Pharmacology and Toxicology, Faculty of Medicine, LMU Munich, Munich, Germany
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31
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Blanchard C, Boué-Grabot E, Massé K. Comparative Embryonic Spatio-Temporal Expression Profile Map of the Xenopus P2X Receptor Family. Front Cell Neurosci 2019; 13:340. [PMID: 31402854 PMCID: PMC6676501 DOI: 10.3389/fncel.2019.00340] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Accepted: 07/10/2019] [Indexed: 01/27/2023] Open
Abstract
P2X receptors are ATP-gated cations channels formed by the homo or hetero-trimeric association from the seven cloned subunits (P2X1-7). P2X receptors are widely distributed in different organs and cell types throughout the body including the nervous system and are involved in a large variety of physiological but also pathological processes in adult mammals. However, their expression and function during embryogenesis remain poorly understood. Here, we report the cloning and the comparative expression map establishment of the entire P2X subunit family in the clawed frog Xenopus. Orthologous sequences for 6 mammalian P2X subunits were identified in both X. laevis and X. tropicalis, but not for P2X3 subunit, suggesting a potential loss of this subunit in the Pipidae family. Three of these genes (p2rx1, p2rx2, and p2rx5) exist as homeologs in the pseudoallotetraploid X. laevis, making a total of 9 subunits in this species. Phylogenetic analyses demonstrate the high level of conservation of these receptors between amphibian and other vertebrate species. RT-PCR revealed that all subunits are expressed during the development although zygotic p2rx6 and p2rx7 transcripts are mainly detected at late organogenesis stages. Whole mount in situ hybridization shows that each subunit displays a specific spatio-temporal expression profile and that these subunits can therefore be grouped into two groups, based on their expression or not in the developing nervous system. Overlapping expression in the central and peripheral nervous system and in the sensory organs suggests potential heteromerization and/or redundant functions of P2X subunits in Xenopus embryos. The developmental expression of the p2rx subunit family during early phases of embryogenesis indicates that these subunits may have distinct roles during vertebrate development, especially embryonic neurogenesis.
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Affiliation(s)
- Camille Blanchard
- Université de Bordeaux, Institut des Maladies Neurodégénératives, UMR 5293, Bordeaux, France
- CNRS, Institut des Maladies Neurodégénératives, UMR 5293, Bordeaux, France
| | - Eric Boué-Grabot
- Université de Bordeaux, Institut des Maladies Neurodégénératives, UMR 5293, Bordeaux, France
- CNRS, Institut des Maladies Neurodégénératives, UMR 5293, Bordeaux, France
| | - Karine Massé
- Université de Bordeaux, Institut des Maladies Neurodégénératives, UMR 5293, Bordeaux, France
- CNRS, Institut des Maladies Neurodégénératives, UMR 5293, Bordeaux, France
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32
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Ase AR, Therrien É, Séguéla P. An Allosteric Inhibitory Site Conserved in the Ectodomain of P2X Receptor Channels. Front Cell Neurosci 2019; 13:121. [PMID: 31024257 PMCID: PMC6465887 DOI: 10.3389/fncel.2019.00121] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Accepted: 03/12/2019] [Indexed: 12/27/2022] Open
Abstract
P2X receptors constitute a gene family of cation channels gated by extracellular ATP. They mediate fast ionotropic purinergic signaling in neurons and non-excitable cell types in vertebrates. The highly calcium-permeable P2X4 subtype has been shown to play a significant role in cardiovascular physiology, inflammatory responses and neuro-immune communication. We previously reported the discovery of a P2X4-selective antagonist, the small organic compound BX430, with submicromolar potency for human P2X4 receptors and marked species-dependence (Ase et al., 2015). The present study investigates the molecular basis of P2X4 inhibition by the non-competitive blocker BX430 using a structural and functional approach relying on mutagenesis and electrophysiology. We provide evidence for the critical contribution of a single hydrophobic residue located in the ectodomain of P2X4 channel subunits, Ile312 in human P2X4, which determines blockade by BX430. We also show that the nature of this extracellular residue in various vertebrate P2X4 orthologs underlies their specific sensitivity or resistance to the inhibitory effects of BX430. Taking advantage of high-resolution crystallographic data available on zebrafish P2X4, we used molecular dynamics simulation to model the docking of BX430 on an allosteric binding site around Ile315 (zebrafish numbering) in the ectodomain of P2X4. We also observed that the only substitution I312D (human numbering) that renders P2X4 silent by itself has also a profound silencing effect on all other P2X subtypes tested when introduced at homologous positions. The generic impact of this aspartate mutation on P2X function indicates that the pre-TM2 subregion involved is conserved functionally and defines a novel allosteric inhibitory site present in all P2X receptor channels. This conserved structure-channel activity relationship might be exploited for the rational design of potent P2X subtype-selective antagonists of therapeutic value.
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Affiliation(s)
- Ariel R Ase
- Alan Edwards Centre for Research on Pain, Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, QC, Canada
| | | | - Philippe Séguéla
- Alan Edwards Centre for Research on Pain, Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, QC, Canada
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33
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Kaczmarek-Hajek K, Zhang J, Kopp R, Grosche A, Rissiek B, Saul A, Bruzzone S, Engel T, Jooss T, Krautloher A, Schuster S, Magnus T, Stadelmann C, Sirko S, Koch-Nolte F, Eulenburg V, Nicke A. Re-evaluation of neuronal P2X7 expression using novel mouse models and a P2X7-specific nanobody. eLife 2018; 7:36217. [PMID: 30074479 PMCID: PMC6140716 DOI: 10.7554/elife.36217] [Citation(s) in RCA: 111] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Accepted: 07/31/2018] [Indexed: 12/18/2022] Open
Abstract
The P2X7 channel is involved in the pathogenesis of various CNS diseases. An increasing number of studies suggest its presence in neurons where its putative functions remain controversial for more than a decade. To resolve this issue and to provide a model for analysis of P2X7 functions, we generated P2X7 BAC transgenic mice that allow visualization of functional EGFP-tagged P2X7 receptors in vivo. Extensive characterization of these mice revealed dominant P2X7-EGFP protein expression in microglia, Bergmann glia, and oligodendrocytes, but not in neurons. These findings were further validated by microglia- and oligodendrocyte-specific P2X7 deletion and a novel P2X7-specific nanobody. In addition to the first quantitative analysis of P2X7 protein expression in the CNS, we show potential consequences of its overexpression in ischemic retina and post-traumatic cerebral cortex grey matter. This novel mouse model overcomes previous limitations in P2X7 research and will help to determine its physiological roles and contribution to diseases. The human body relies on a molecule called ATP as an energy source and as a messenger. When cells die, for example if they are damaged or because of inflammation, they release large amounts of ATP into their environment. Their neighbors can detect the outpouring of ATP through specific receptors, the proteins that sit at the cell’s surface and can bind external agents. Scientists believe that one of these ATP-binding receptors, P2X7, responds to high levels of ATP by triggering a cascade of reactions that results in inflammation and cell death. P2X7 also seems to play a role in several brain diseases such as epilepsia and Alzheimer’s, but the exact mechanisms are not known. In particular, how this receptor is involved in the death of neurons is unclear, and researchers still debate whether P2X7 is present in neurons and in other types of brain cells. To answer this, Kaczmarek-Hájek, Zhang, Kopp et al. created genetically modified mice in which the P2X7 receptors carry a fluorescent dye. Powerful microscopes can pick up the light signal from the dye and help to reveal which cells have the receptors. These experiments show that neurons do not carry the protein; instead, P2X7 is present in certain brain cells that keep the neurons healthy. For example, it is found in the immune cells that ‘clean up’ the organ, and the cells that support and insulate neurons. Kaczmarek-Hájek et al. further provide preliminary data suggesting that, under certain conditions, if too many P2X7 receptors are present in these cells neuronal damage might be increased. It is therefore possible that the brain cells that carry P2X7 indirectly contribute to the death of neurons when large amounts of ATP are released. The genetically engineered mouse designed for the experiments could be used in further studies to dissect the role that P2X7 plays in diseases of the nervous system. In particular, this mouse model might help to understand whether the receptor could become a drug target for neurodegenerative conditions.
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Affiliation(s)
- Karina Kaczmarek-Hajek
- Department of Molecular Biology of Neuronal Signals, Max Planck Institute for Experimental Medicine, Göttingen, Germany
| | - Jiong Zhang
- Department of Molecular Biology of Neuronal Signals, Max Planck Institute for Experimental Medicine, Göttingen, Germany.,Walther Straub Institute for Pharmacology and Toxicology, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Robin Kopp
- Walther Straub Institute for Pharmacology and Toxicology, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Antje Grosche
- Institute for Human Genetics, University of Regensburg, Regensburg, Germany.,Department of Physiological Genomics, Ludwig-Maximilians-Universität München, München, Germany
| | - Björn Rissiek
- Department of Neurology, University Hospital Hamburg-Eppendorf, Hamburg, Germany
| | - Anika Saul
- Department of Molecular Biology of Neuronal Signals, Max Planck Institute for Experimental Medicine, Göttingen, Germany
| | - Santina Bruzzone
- Department of Experimental Medicine and CEBR, University of Genova, Genova, Italy
| | - Tobias Engel
- Department of Physiology and Medical Physics, Royal College of Surgeons in Ireland, Dublin, Ireland
| | - Tina Jooss
- Walther Straub Institute for Pharmacology and Toxicology, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Anna Krautloher
- Walther Straub Institute for Pharmacology and Toxicology, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Stefanie Schuster
- Institute of Biochemistry, University Erlangen-Nürnberg, Erlangen, Germany
| | - Tim Magnus
- Department of Neurology, University Hospital Hamburg-Eppendorf, Hamburg, Germany
| | | | - Swetlana Sirko
- Department of Physiological Genomics, Ludwig-Maximilians-Universität München, München, Germany.,Institute of Stem Cell Research, Helmholtz Center Munich, German Research Center for Environmental Health (GmbH), Neuherberg, Germany
| | - Friedrich Koch-Nolte
- Department of Immunology, University Hospital Hamburg-Eppendorf, Hamburg, Germany
| | - Volker Eulenburg
- Institute of Biochemistry, University Erlangen-Nürnberg, Erlangen, Germany.,Department of Anaesthesiology and Intensive Care Therapy, University of Leipzig, Leipzig, Germany
| | - Annette Nicke
- Department of Molecular Biology of Neuronal Signals, Max Planck Institute for Experimental Medicine, Göttingen, Germany.,Walther Straub Institute for Pharmacology and Toxicology, Ludwig-Maximilians-Universität München, Munich, Germany
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34
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Peverini L, Beudez J, Dunning K, Chataigneau T, Grutter T. New Insights Into Permeation of Large Cations Through ATP-Gated P2X Receptors. Front Mol Neurosci 2018; 11:265. [PMID: 30108481 PMCID: PMC6080412 DOI: 10.3389/fnmol.2018.00265] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Accepted: 07/13/2018] [Indexed: 11/28/2022] Open
Abstract
The permeability of large cations through the P2X pore has remained arguably the most controversial and complicated topic in P2X-related research, with the emergence of conflicting studies on the existence, mechanism and physiological relevance of a so-called “dilated” state. Due to the important role of several “dilating” P2X subtypes in numerous diseases, a clear and detailed understanding of this phenomenon represents a research priority. Recent advances, however, have challenged the existence of a progressive, ATP-induced pore dilation, by demonstrating that this phenomenon is an artifact of the method employed. Here, we discuss briefly the history of this controversial and enigmatic dilated state, from its initial discovery to its recent reconsideration. We will discuss the literature in which mechanistic pathways to a large cation-permeable state are proposed, as well as important advances in the methodology employed to study this elusive state. Considering recent literature, we will also open the discussion as to whether an intrinsically dilating P2X pore exists, as well as the physiological relevance of such a large cation-permeable pore and its potential use as therapeutic pathway.
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Affiliation(s)
- Laurie Peverini
- CNRS, CAMB UMR 7199, Équipe de Chimie et Neurobiologie Moléculaire, Université de Strasbourg, Strasbourg, France
| | - Juline Beudez
- CNRS, CAMB UMR 7199, Équipe de Chimie et Neurobiologie Moléculaire, Université de Strasbourg, Strasbourg, France
| | - Kate Dunning
- CNRS, CAMB UMR 7199, Équipe de Chimie et Neurobiologie Moléculaire, Université de Strasbourg, Strasbourg, France
| | - Thierry Chataigneau
- CNRS, CAMB UMR 7199, Équipe de Chimie et Neurobiologie Moléculaire, Université de Strasbourg, Strasbourg, France
| | - Thomas Grutter
- CNRS, CAMB UMR 7199, Équipe de Chimie et Neurobiologie Moléculaire, Université de Strasbourg, Strasbourg, France
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35
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Stephan G, Huang L, Tang Y, Vilotti S, Fabbretti E, Yu Y, Nörenberg W, Franke H, Gölöncsér F, Sperlágh B, Dopychai A, Hausmann R, Schmalzing G, Rubini P, Illes P. The ASIC3/P2X3 cognate receptor is a pain-relevant and ligand-gated cationic channel. Nat Commun 2018; 9:1354. [PMID: 29636447 PMCID: PMC5893604 DOI: 10.1038/s41467-018-03728-5] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2017] [Accepted: 03/09/2018] [Indexed: 12/21/2022] Open
Abstract
Two subclasses of acid-sensing ion channels (ASIC3) and of ATP-sensitive P2X receptors (P2X3Rs) show a partially overlapping expression in sensory neurons. Here we report that both recombinant and native receptors interact with each other in multiple ways. Current measurements with the patch-clamp technique prove that ASIC3 stimulation strongly inhibits the P2X3R current partly by a Ca2+-dependent mechanism. The proton-binding site is critical for this effect and the two receptor channels appear to switch their ionic permeabilities during activation. Co-immunoprecipation proves the close association of the two protein structures. BN-PAGE and SDS-PAGE analysis is also best reconciled with the view that ASIC3 and P2X3Rs form a multiprotein structure. Finally, in vivo measurements in rats reveal the summation of pH and purinergically induced pain. In conclusion, the receptor subunits do not appear to form a heteromeric channel, but tightly associate with each other to form a protein complex, mediating unidirectional inhibition. Two subclasses of ligand-gated ion channels (ASIC3 and P2X3) are both present at sensory neurons and might be therefore subject to receptor crosstalk. Here authors use electrophysiology, biochemistry and co-immunoprecipitation to show that the two ion channels interact and affect P2X3 currents.
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Affiliation(s)
- Gabriele Stephan
- Rudolf-Boehm-Institut für Pharmakologie und Toxikologie, University of Leipzig, Leipzig, 04107, Germany
| | - Lumei Huang
- Rudolf-Boehm-Institut für Pharmakologie und Toxikologie, University of Leipzig, Leipzig, 04107, Germany.,Acupuncture and Tuina School, Chengdu University of Traditional Chinese Medicine, Chengdu, 610075, China
| | - Yong Tang
- Acupuncture and Tuina School, Chengdu University of Traditional Chinese Medicine, Chengdu, 610075, China
| | - Sandra Vilotti
- Neurobiology Sector, International School for Advanced Studies, Trieste, 34136, Italy
| | - Elsa Fabbretti
- Department of Life Sciences, University of Trieste, Trieste, 34127, Italy
| | - Ye Yu
- Institute of Neuroscience and State Key Laboratory of Neuroscience, Shanghai, 100025, China
| | - Wolfgang Nörenberg
- Rudolf-Boehm-Institut für Pharmakologie und Toxikologie, University of Leipzig, Leipzig, 04107, Germany
| | - Heike Franke
- Rudolf-Boehm-Institut für Pharmakologie und Toxikologie, University of Leipzig, Leipzig, 04107, Germany
| | - Flóra Gölöncsér
- Laboratory of Molecular Pharmacology, Institute of Experimental Medicine, Hungarian Academy of Sciences, Budapest, 1043, Hungary.,János Szentágothai School of Neurosciences, Semmelweis University School of PhD Studies, Budapest, 1043, Hungary
| | - Beáta Sperlágh
- Laboratory of Molecular Pharmacology, Institute of Experimental Medicine, Hungarian Academy of Sciences, Budapest, 1043, Hungary
| | - Anke Dopychai
- Molecular Pharmacology, Rheinisch-Westfälische Technische Hochschule (RWTH) Aachen University, Aachen, 52072, Germany
| | - Ralf Hausmann
- Molecular Pharmacology, Rheinisch-Westfälische Technische Hochschule (RWTH) Aachen University, Aachen, 52072, Germany
| | - Günther Schmalzing
- Molecular Pharmacology, Rheinisch-Westfälische Technische Hochschule (RWTH) Aachen University, Aachen, 52072, Germany
| | - Patrizia Rubini
- Rudolf-Boehm-Institut für Pharmakologie und Toxikologie, University of Leipzig, Leipzig, 04107, Germany
| | - Peter Illes
- Rudolf-Boehm-Institut für Pharmakologie und Toxikologie, University of Leipzig, Leipzig, 04107, Germany.
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36
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Yu W, Hill WG, Robson SC, Zeidel ML. Role of P2X 4 Receptor in Mouse Voiding Function. Sci Rep 2018; 8:1838. [PMID: 29382907 PMCID: PMC5789870 DOI: 10.1038/s41598-018-20216-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Accepted: 01/16/2018] [Indexed: 01/16/2023] Open
Abstract
Purinergic signalling plays an important role in the regulation of bladder smooth muscle (BSM) contractility, and P2X4 receptor is expressed in the bladder wall, where it may act by forming heteromeric receptors with P2X1, the major purinergic force-generating muscle receptor. To test this hypothesis, we examined mouse BSM contractile properties in the absence and presence of selective P2X1 (NF449 & NF279) and P2X4 antagonists (5-BDBD). These drugs inhibited BSM purinergic contraction only partially, suggesting the possibility of a heteromeric receptor. However, carefully controlled co-immunoprecipitation experiments indicated that P2X1 and P2X4 do not form physically linked heteromers. Furthermore, immunofluorescence staining showed that P2X4 is not present in mouse BSM per se, but in an unknown cellular structure among BSM bundles. To investigate whether deletion of P2X4 could impact voiding function in vivo, P2X4 null mice were characterized. P2X4 null mice had normal bladder weight and morphology, normal voiding spot size and number by voiding spot assay, normal voiding interval, pressure and compliance by cystometrogram, and normal BSM contractility by myography. In conclusion, these data strongly suggest that P2X4 is not present in mouse BSM cells, does not affect smooth muscle contractility and that mice null for P2X4 exhibit normal voiding function.
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Affiliation(s)
- Weiqun Yu
- Department of Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachuesetts, USA.
| | - Warren G Hill
- Department of Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachuesetts, USA
| | - Simon C Robson
- Department of Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachuesetts, USA
| | - Mark L Zeidel
- Department of Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachuesetts, USA
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37
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Schneider M, Prudic K, Pippel A, Klapperstück M, Braam U, Müller CE, Schmalzing G, Markwardt F. Interaction of Purinergic P2X4 and P2X7 Receptor Subunits. Front Pharmacol 2017; 8:860. [PMID: 29213241 PMCID: PMC5702805 DOI: 10.3389/fphar.2017.00860] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2017] [Accepted: 11/09/2017] [Indexed: 11/13/2022] Open
Abstract
P2X4 and P2X7 are members of the P2X receptor family, comprising seven isoforms (P2X1–P2X7) that form homo- and heterotrimeric non-specific cation channels gated by extracellular ATP. P2X4 and P2X7 are widely coexpressed, particularly in secretory epithelial cells and immune and inflammatory cells, and regulate inflammation and nociception. Although functional heteromerization has been established for P2X2 and P2X3 subunits expressed in sensory neurons, there are contradictory reports regarding a functional interaction between P2X4 and P2X7 subunits. To resolve this issue, we coexpressed P2X4 and P2X7 receptor subunits labeled with green (EGFP) and red (TagRFP) fluorescent proteins in Xenopus laevis oocytes and investigated a putative physical interaction between the fusion proteins by Förster resonance energy transfer (FRET). Coexpression of P2X4 and P2X7 subunits with EGFP and TagRFP located in the extracellular receptor domains led to significant FRET signals. Significant FRET signals were also measured between C-terminally fluorophore-labeled full-length P2X41-384 and C-terminally truncated fluorescent P2X71-408 subunits. We furthermore used the two-electrode voltage clamp technique to investigate whether human P2X4 and P2X7 receptors (hP2X4, hP2X7) functionally interact at the level of ATP-induced whole-cell currents. Concentration–response curves and effects of ivermectin (P2X4-potentiating drug) or BzATP (P2X7-specific agonist) were consistent with a model in which coexpressed hP2X4 and hP2X7 do not interact. Similarly, the effect of adding specific inhibitors of P2X4 (PSB-15417) or P2X7 (oATP, A438079) could be explained by a model in which only homomers exist, and that these are blocked by the respective antagonist. In conclusion, we show that P2X4 and P2X7 subunits can form heterotrimeric P2X4/P2X7 receptors. However, unlike observations for P2X2 and P2X3, coexpression of P2X4 and P2X7 subunits does not result in a novel electrophysiologically discriminable P2X receptor phenotype.
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Affiliation(s)
- Markus Schneider
- Julius-Bernstein-Institute for Physiology, Martin-Luther-University, Halle, Germany
| | - Kirsten Prudic
- Julius-Bernstein-Institute for Physiology, Martin-Luther-University, Halle, Germany
| | - Anja Pippel
- Julius-Bernstein-Institute for Physiology, Martin-Luther-University, Halle, Germany
| | - Manuela Klapperstück
- Julius-Bernstein-Institute for Physiology, Martin-Luther-University, Halle, Germany
| | - Ursula Braam
- Molecular Pharmacology, RWTH Aachen University, Aachen, Germany
| | - Christa E Müller
- Pharmaceutical Institute, Pharmaceutical Chemistry I, University of Bonn, Bonn, Germany
| | | | - Fritz Markwardt
- Julius-Bernstein-Institute for Physiology, Martin-Luther-University, Halle, Germany
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38
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Zhu Y, Beudez J, Yu N, Grutter T, Zhao HB. P2X2 Dominant Deafness Mutations Have No Negative Effect on Wild-Type Isoform: Implications for Functional Rescue and in Deafness Mechanism. Front Mol Neurosci 2017; 10:371. [PMID: 29180951 PMCID: PMC5693881 DOI: 10.3389/fnmol.2017.00371] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2017] [Accepted: 10/26/2017] [Indexed: 11/13/2022] Open
Abstract
The P2X2 receptor is an ATP-gated ion channel, assembled by three subunits. Recently, it has been found that heterozygous mutations of P2X2 V60L and G353R can cause autosomal dominant nonsyndromic hearing loss. However, the underlying mechanism remains unclear. The fact that heterozygous mutations cause deafness suggests that the mutations may have dominant-negative effect (DNE) on wild-type (WT) P2X2 isoforms and/or other partners leading to hearing loss. In this study, the effect of these dominant deafness P2X2 mutations on WT P2X2 was investigated. We found that sole transfection of both V60L and G353R deafness mutants could efficiently target to the plasma membrane, like WT P2X2, but exhibit a significantly reduced response to ATP stimulation. Both mutants reduced the channel conductance, but G353R mutation also altered the voltage dependency. Co-expression with WT P2X2 could restore the response to ATP. As the ratio of WT P2X2 vs. mutants increased, the response to ATP was also increased. Computer modeling confirmed that both V60L and G353R dominant-deafness mutant subunits do not have any negative effect on WT P2X2 subunit, when assembled as a heterotrimer. Improper docking or defective gating is the more likely mechanism for impaired channel function by these P2X2 deafness mutations. These results suggest that P2X2 dominant deafness mutations do not have negative effects on WT P2X2 isoforms, and that adding additional WT P2X2 could rescue the lost channel function caused by the deafness mutations. These P2X2 dominant deafness mutations may have negative-effects on other partners leading to hearing loss.
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Affiliation(s)
- Yan Zhu
- Department of Otolaryngology, University of Kentucky Medical Center, Lexington, KY, United States
| | - Juline Beudez
- Centre National de la Recherche Scientifique, Unité Mixte de Recherche 7199, Laboratoire de Conception et Application de Molécules Bioactives, Équipe de Chimie et Neurobiologie Moléculaire, Strasbourg, France.,Faculté de Pharmacie, Université de Strasbourg, Strasbourg, France
| | - Ning Yu
- Department of Otolaryngology, University of Kentucky Medical Center, Lexington, KY, United States.,Department of Otolaryngology, Institute of Otolaryngology, Chinese PLA General Hospital, Beijing, China
| | - Thomas Grutter
- Centre National de la Recherche Scientifique, Unité Mixte de Recherche 7199, Laboratoire de Conception et Application de Molécules Bioactives, Équipe de Chimie et Neurobiologie Moléculaire, Strasbourg, France.,Faculté de Pharmacie, Université de Strasbourg, Strasbourg, France
| | - Hong-Bo Zhao
- Department of Otolaryngology, University of Kentucky Medical Center, Lexington, KY, United States
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39
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Kotova PD, Bystrova MF, Rogachevskaja OA, Khokhlov AA, Sysoeva VY, Tkachuk VA, Kolesnikov SS. Coupling of P2Y receptors to Ca 2+ mobilization in mesenchymal stromal cells from the human adipose tissue. Cell Calcium 2017; 71:1-14. [PMID: 29604959 DOI: 10.1016/j.ceca.2017.11.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2017] [Revised: 10/25/2017] [Accepted: 11/06/2017] [Indexed: 12/19/2022]
Abstract
The purinergic transduction was examined in mesenchymal stromal cells (MSCs) from the human adipose tissue, and several nucleotides, including ATP, UTP, and ADP, were found to mobilize cytosolic Ca2+. Transcripts for multiple purinoreceptors were detected in MSC preparations, including A1, A2A, A2B, P2Y1, P2Y2, P2Y4, P2Y6, P2Y11, P2Y13, P2Y14, P2X2, P2X4, and P2X7. Cellular responses to nucleotides were insignificantly sensitive to bath Ca2+, pointing at a minor contribution of Ca2+ entry, and were suppressed by U73122 and 2-APB, implicating the phosphoinositide cascade in coupling P2Y receptors to Ca2+ release. While individual cells were sensitive to several P2Y agonists, responsiveness to a given nucleotide varied from cell to cell, suggesting that particular MSCs could employ different sets of purinoreceptors. Caged Ca2+ stimulated Ca2+-induced Ca2+ release (CICR) that was mediated largely by IP3 receptors, and resultant Ca2+ transients were similar to nucleotide responses by magnitude and kinetics. A variety of findings hinted at CICR to be a universal mechanism that finalizes Ca2+ signaling initiated by agonists in MSCs. Individual MSCs responded to nucleotides in an all-or-nothing manner. Presumably just CICR provided invariant Ca2+ responses observed in MSCs at different nucleotide concentrations. The effects of isoform specific agonists and antagonists suggested that both P2Y1 and P2Y13 were obligatory for ADP responses, while P2Y4 and P2Y11 served as primary UTP and ATP receptors, respectively. Extracellular NAD+ stimulated Ca2+ signaling in each ATP-responsive MSC by involving P2Y11. The overall data indicate that extracellular nucleotides and NAD+ can serve as autocrine/paracrine factors regulating MSC functions.
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Affiliation(s)
- Polina D Kotova
- Institute of Cell Biophysics, Russian Academy of Sciences, Institutional Street 3, Pushchino, Moscow Region, 142290, Russia
| | - Marina F Bystrova
- Institute of Cell Biophysics, Russian Academy of Sciences, Institutional Street 3, Pushchino, Moscow Region, 142290, Russia
| | - Olga A Rogachevskaja
- Institute of Cell Biophysics, Russian Academy of Sciences, Institutional Street 3, Pushchino, Moscow Region, 142290, Russia
| | - Alexander A Khokhlov
- Institute of Cell Biophysics, Russian Academy of Sciences, Institutional Street 3, Pushchino, Moscow Region, 142290, Russia
| | - Veronika Yu Sysoeva
- Department of Biochemistry and Molecular Medicine, Faculty of Basic Medicine, Lomonosov Moscow State University, Russia
| | - Vsevolod A Tkachuk
- Department of Biochemistry and Molecular Medicine, Faculty of Basic Medicine, Lomonosov Moscow State University, Russia
| | - Stanislav S Kolesnikov
- Institute of Cell Biophysics, Russian Academy of Sciences, Institutional Street 3, Pushchino, Moscow Region, 142290, Russia.
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40
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Stokes L, Layhadi JA, Bibic L, Dhuna K, Fountain SJ. P2X4 Receptor Function in the Nervous System and Current Breakthroughs in Pharmacology. Front Pharmacol 2017; 8:291. [PMID: 28588493 PMCID: PMC5441391 DOI: 10.3389/fphar.2017.00291] [Citation(s) in RCA: 100] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2017] [Accepted: 05/05/2017] [Indexed: 12/18/2022] Open
Abstract
Adenosine 5′-triphosphate is a well-known extracellular signaling molecule and neurotransmitter known to activate purinergic P2X receptors. Information has been elucidated about the structure and gating of P2X channels following the determination of the crystal structure of P2X4 (zebrafish), however, there is still much to discover regarding the role of this receptor in the central nervous system (CNS). In this review we provide an overview of what is known about P2X4 expression in the CNS and discuss evidence for pathophysiological roles in neuroinflammation and neuropathic pain. Recent advances in the development of pharmacological tools including selective antagonists (5-BDBD, PSB-12062, BX430) and positive modulators (ivermectin, avermectins, divalent cations) of P2X4 will be discussed.
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Affiliation(s)
- Leanne Stokes
- School of Pharmacy, University of East Anglia, Norwich Research ParkNorwich, United Kingdom.,School of Biomedical and Health Sciences, RMIT University, BundooraVIC, Australia
| | - Janice A Layhadi
- Biomedical Research Centre, School of Biological Sciences, University of East AngliaNorwich, United Kingdom
| | - Lucka Bibic
- School of Pharmacy, University of East Anglia, Norwich Research ParkNorwich, United Kingdom
| | - Kshitija Dhuna
- School of Biomedical and Health Sciences, RMIT University, BundooraVIC, Australia
| | - Samuel J Fountain
- Biomedical Research Centre, School of Biological Sciences, University of East AngliaNorwich, United Kingdom
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41
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Gicquel T, Le Daré B, Boichot E, Lagente V. Purinergic receptors: new targets for the treatment of gout and fibrosis. Fundam Clin Pharmacol 2016; 31:136-146. [PMID: 27885718 DOI: 10.1111/fcp.12256] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Revised: 11/02/2016] [Accepted: 11/18/2016] [Indexed: 12/11/2022]
Abstract
Adenosine triphosphate is involved in many metabolic reactions, but it has also a role as a cellular danger signal transmitted through purinergic receptors (PRs). Indeed, adenosine 5'-triphosphate (ATP) can bind to PRs which are found in the membrane of many cell types, although the relative proportions of the receptor subtypes differ. PRs are classified according to genetic and pharmacological criteria and especially their affinities for agonists and their transduction mechanism (i.e. as metabotropic P2YRs or ionotropic P2XRs). Extracellular ATP release by activated or necrotic cells may activate various PRs and especially P2X7R, the best-characterized PR, on immune cells. P2X7R is known to regulate the activation of the Nod-like receptor (NLR)-family protein, NLRP3 inflammasome, which permit the release of IL-1β, a potent pro-inflammatory cytokine. The P2X7R/NLRP3 pathway is involved in many inflammatory diseases, such as gout, and in fibrosis diseases associated with inflammatory process, liver or lung fibrosis. Some authors imaging also a real promising therapeutic potential of P2X7R blockage. Thus, several pharmaceutical companies have developed P2X7R antagonists as novel anti-inflammatory drug candidates. Clinical trials of the efficacy of these antagonists are now underway. A better understanding of the P2X7R/NLRP3 signalling pathways permits the identification of targets and the development of a new class of drugs able to inhibit the fibrogenesis process and collagen deposition.
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Affiliation(s)
- Thomas Gicquel
- Laboratoire de toxicologie biologique et médico-légale, CHU Rennes, F-35033, Rennes, France.,UMR991 INSERM, Faculté de Pharmacie, Université Rennes 1, F-35043, Rennes, France
| | - Brendan Le Daré
- UMR991 INSERM, Faculté de Pharmacie, Université Rennes 1, F-35043, Rennes, France.,CHU Rennes, Pôle Pharmacie, F-35033, Rennes, France
| | - Elisabeth Boichot
- UMR991 INSERM, Faculté de Pharmacie, Université Rennes 1, F-35043, Rennes, France
| | - Vincent Lagente
- UMR991 INSERM, Faculté de Pharmacie, Université Rennes 1, F-35043, Rennes, France
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42
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Carracedo G, Crooke A, Guzman-Aranguez A, Pérez de Lara MJ, Martin-Gil A, Pintor J. The role of dinucleoside polyphosphates on the ocular surface and other eye structures. Prog Retin Eye Res 2016; 55:182-205. [PMID: 27421962 DOI: 10.1016/j.preteyeres.2016.07.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2016] [Revised: 06/30/2016] [Accepted: 07/05/2016] [Indexed: 11/17/2022]
Abstract
Dinucleoside polyphosphates comprises a group of dinucleotides formed by two nucleosides linked by a variable number of phosphates, abbreviated NpnN (where n represents the number of phosphates). These compounds are naturally occurring substances present in tears, aqueous humour and in the retina. As the consequence of their presence, these dinucleotides contribute to many ocular physiological processes. On the ocular surface, dinucleoside polyphosphates can stimulate tear secretion, mucin release from goblet cells and they help epithelial wound healing by accelerating cell migration rate. These dinucleotides can also stimulate the presence of proteins known to protect the ocular surface against microorganisms, such as lysozyme and lactoferrin. One of the latest discoveries is the ability of some dinucleotides to facilitate the paracellular way on the cornea, therefore allowing the delivery of compounds, such as antiglaucomatous ones, more easily within the eye. The compound Ap4A has been described being abnormally elevated in patient's tears suffering of dry eye, Sjogren syndrome, congenital aniridia, or after refractive surgery, suggesting this molecule as biomarker for dry eye condition. At the intraocular level, some diadenosine polyphosphates are abnormally elevated in glaucoma patients, and this can be related to the stimulation of a P2Y2 receptor that increases the chloride efflux and water movement in the ciliary epithelium. In the retina, the dinucleotide dCp4U, has been proven to be useful to help in the recovery of retinal detachments. Altogether, dinucleoside polyphosphates are a group of compounds which present relevant physiological actions but which also can perform promising therapeutic benefits.
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Affiliation(s)
- Gonzalo Carracedo
- Department of Optics II (Optometry and Vision), Faculty of Optics and Optometry, Universidad Complutense de Madrid, Madrid, Spain
| | - Almudena Crooke
- Department of Biochemistry and Molecular Biology IV, Faculty of Optics and Optometry, Universidad Complutense de Madrid, Madrid, Spain
| | - Ana Guzman-Aranguez
- Department of Biochemistry and Molecular Biology IV, Faculty of Optics and Optometry, Universidad Complutense de Madrid, Madrid, Spain
| | - Maria J Pérez de Lara
- Department of Biochemistry and Molecular Biology IV, Faculty of Optics and Optometry, Universidad Complutense de Madrid, Madrid, Spain
| | - Alba Martin-Gil
- Department of Biochemistry and Molecular Biology IV, Faculty of Optics and Optometry, Universidad Complutense de Madrid, Madrid, Spain
| | - Jesús Pintor
- Department of Biochemistry and Molecular Biology IV, Faculty of Optics and Optometry, Universidad Complutense de Madrid, Madrid, Spain.
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43
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Ribeiro-Filho AC, Buri MV, Barros CC, Dreyfuss JL, Nader HB, Justo GZ, Craveiro RB, Pesquero JB, Miranda A, Ferreira AT, Paredes-Gamero EJ. Functional and molecular evidence for heteromeric association of P2Y1 receptor with P2Y2 and P2Y4 receptors in mouse granulocytes. BMC Pharmacol Toxicol 2016; 17:29. [PMID: 27384918 PMCID: PMC4936188 DOI: 10.1186/s40360-016-0072-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2015] [Accepted: 06/24/2016] [Indexed: 12/27/2022] Open
Abstract
BACKGROUND All hematopoietic cells express P2 receptors, however pharmacological characteristics such as expression and affinity in granulocytes are unknown. METHODS Pharmacological characteristics of P2 receptors were evaluated by Ca(2+) measurements using Fura-2 fluorophore. P2 receptors expression were analyzed by flow cytometry and RT-PCR. P2 interaction were shown by coimmunoprecipitation, western blotting and FRET. RESULTS Granulocytes were responsive to P2Y agonists, whereas P2X agonists were ineffective. Ca(2+) increase, elicited by ADP and UTP was dependent on intracellular stocks and sensitive to G-coupled receptor inhibition. Moreover, MRS2179, a specific antagonist of the P2Y1 receptor, abolished ADP response. Interestingly, ADP and UTP exhibited full heterologous desensitization, suggesting that these agonists interact with the same receptor. The heteromeric association between P2Y1 receptor and the P2Y2 and P2Y4 receptors was shown by immunoprecipitation and FRET analysis. CONCLUSION Clear evidence of heteromeric association of P2Y receptors was found during the evaluation of P2 receptors present in mice granulocytes, which could impact in the classical pharmacology of P2Y receptors in granulocytes.
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Affiliation(s)
- Antonio Carlos Ribeiro-Filho
- Centro Interdisciplinar de Investigação Bioquı́mica, Universidade de Mogi das Cruzes, Av. Dr Cândido Xavier de Almeida Souza, 200, Mogi das Cruzes, São Paulo, Brazil
| | - Marcus Vinicius Buri
- Departamento de Bioquímica, Universidade Federal de São Paulo, Rua Pedro de Toledo, 669 - 9° andar - Prédio de Pesquisa II, R. Três de Maio 100, São Paulo, São Paulo, Brazil
| | - Carlos Castilho Barros
- Departamento de Nutrição, Universidade Federal de Pelotas, R. Gomes Carneiro, n°1, 96010-610, Pelotas, Rio Grande do Sul, Brazil
| | - Juliana Luporini Dreyfuss
- Departamento de Bioquímica, Universidade Federal de São Paulo, Rua Pedro de Toledo, 669 - 9° andar - Prédio de Pesquisa II, R. Três de Maio 100, São Paulo, São Paulo, Brazil
| | - Helena Bonciani Nader
- Departamento de Bioquímica, Universidade Federal de São Paulo, Rua Pedro de Toledo, 669 - 9° andar - Prédio de Pesquisa II, R. Três de Maio 100, São Paulo, São Paulo, Brazil
| | - Giselle Zenker Justo
- Departamento de Bioquímica, Universidade Federal de São Paulo, Rua Pedro de Toledo, 669 - 9° andar - Prédio de Pesquisa II, R. Três de Maio 100, São Paulo, São Paulo, Brazil
| | - Rogério Bastos Craveiro
- Departamento de Biofísica, Universidade Federal de São Paulo, R. Botucatu 862, São Paulo, São Paulo, Brazil
| | - João Bosco Pesquero
- Departamento de Biofísica, Universidade Federal de São Paulo, R. Botucatu 862, São Paulo, São Paulo, Brazil
| | - Antonio Miranda
- Departamento de Biofísica, Universidade Federal de São Paulo, R. Botucatu 862, São Paulo, São Paulo, Brazil
| | - Alice Teixeira Ferreira
- Departamento de Biofísica, Universidade Federal de São Paulo, R. Botucatu 862, São Paulo, São Paulo, Brazil
| | - Edgar Julian Paredes-Gamero
- Centro Interdisciplinar de Investigação Bioquı́mica, Universidade de Mogi das Cruzes, Av. Dr Cândido Xavier de Almeida Souza, 200, Mogi das Cruzes, São Paulo, Brazil. .,Departamento de Bioquímica, Universidade Federal de São Paulo, Rua Pedro de Toledo, 669 - 9° andar - Prédio de Pesquisa II, R. Três de Maio 100, São Paulo, São Paulo, Brazil.
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44
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Li S, Chen X, Hao G, Geng X, Zhan W, Sun J. Identification and characterization of ATP-gated P2X2 receptor gene dominantly expressed in the Japanese flounder (Paralichthys olivaceus) head kidney macrophages. FISH & SHELLFISH IMMUNOLOGY 2016; 54:312-321. [PMID: 27103003 DOI: 10.1016/j.fsi.2016.04.020] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2016] [Revised: 03/17/2016] [Accepted: 04/15/2016] [Indexed: 06/05/2023]
Abstract
P2X2 receptor (P2X2R) belongs to the family of purinergic receptors that have been shown to play important roles in regulating host innate immune response. Although the immunologic significance of P2X2R has been studied in mammals, the presence and immune relevance of P2X2R in fish remains unclear. In this study we extended our previous observations by identifying and characterizing a P2X2R ortholog (termed PoP2X2R) from Japanese flounder (Paralichthys olivaceus). Quantitative real-time PCR analysis revealed that PoP2X2R mRNA transcripts are widely distributed in all examined normal tissues and are dominantly expressed in hepatopancreas tissue. In addition, we for the first time showed that multiple P2XR subtypes, including P2X2R, P2X4R and P2X7R are co-expressed in the Japanese flounder head kidney macrophages (HKMs) and peripheral blood lymphocytes (PBLs), indicating that they may assemble into hetero-receptor complex or interact in the form of homotrimers to trigger diverse purinergic signaling in the Japanese flounder immune cells. Compared with the known Japanese flounder P2X4 and P2X7 receptors, however, PoP2X2R is much more abundantly expressed in the Japanese flounder HKM cells, suggesting that PoP2X2R may play an important role in this type of immune cells. Glycosylation and immunohistochemistry analyses revealed that PoP2X2R is a glycoprotein expressed on the plasma membrane. Immune challenges experiments showed that PoP2X2R was significantly induced by LPS, poly(I:C) and zymosan stimulations in the HKM and PBL cells, and by Edwardsiella tarda infections in spleen and gill tissues as well. Taken together, we have identified and characterized a new P2X2R member that is involved in fish innate immune response.
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Affiliation(s)
- Shuo Li
- Tianjin Key Laboratory of Animal and Plant Resistance, College of Life Sciences, Tianjin Normal University, 393 West Binshui Road, Xiqing District, Tianjin 300387, China.
| | - Xiaoli Chen
- Tianjin Key Laboratory of Animal and Plant Resistance, College of Life Sciences, Tianjin Normal University, 393 West Binshui Road, Xiqing District, Tianjin 300387, China
| | - Gaixiang Hao
- Tianjin Key Laboratory of Animal and Plant Resistance, College of Life Sciences, Tianjin Normal University, 393 West Binshui Road, Xiqing District, Tianjin 300387, China
| | - Xuyun Geng
- Tianjin Center for Control and Prevention of Aquatic Animal Infectious Disease, 442 South Jiefang Road, Hexi District, Tianjin 300221, China
| | - Wenbin Zhan
- Laboratory of Pathology and Immunology of Aquatic Animals, LMMEC, Ocean University of China, Qingdao 266003, China
| | - Jinsheng Sun
- Tianjin Key Laboratory of Animal and Plant Resistance, College of Life Sciences, Tianjin Normal University, 393 West Binshui Road, Xiqing District, Tianjin 300387, China.
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A New Mechanism of Receptor Targeting by Interaction between Two Classes of Ligand-Gated Ion Channels. J Neurosci 2016; 36:1456-70. [PMID: 26843630 DOI: 10.1523/jneurosci.2390-15.2016] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
UNLABELLED The 5-HT3 receptors are serotonin-gated ion channels that physically couple with purinergic P2X2 receptors to trigger a functional cross-inhibition leading to reciprocal channel occlusion. Although this functional receptor-receptor coupling seems to serve a modulatory role on both channels, this might not be its main physiological purpose. Using primary cultures of rat hippocampal neurons as a quantitative model of polarized targeting, we show here a novel function for this interaction. In this model, 5-HT3A receptors did not exhibit by themselves the capability of distal targeting in dendrites and axons but required the presence of P2X2R for their proper subcellular localization. 5-HT3AR distal targeting occurred with a delayed time course and exhibited a neuron phenotype dependency. In the subpopulation of neurons expressing endogenous P2X2R, 5-HT3AR distal neuritic localization correlated with P2X2R expression and could be selectively inhibited by P2X2R RNA interference. Cotransfection of both receptors revealed a specific colocalization, cotrafficking in common surface clusters, and the axonal rerouting of 5-HT3AR. The physical association between the two receptors was dependent on the second intracellular loop of the 5-HT3A subunit, but not on the P2X2R C-terminal tail that triggers the functional cross-inhibition with the 5-HT3AR. Together, these data establish that 5-HT3AR distal targeting in axons and dendrites primarily depends on P2X2R expression. Because several P2XR have now been shown to functionally interact with several other members of the 4-TMD family of receptor channels, we propose to reconsider the real functional role for this receptor family, as trafficking partner proteins dynamically involved in other receptors targeting. SIGNIFICANCE STATEMENT So far, receptor targeting mechanisms were found to involve intracellular partner proteins or supramolecular complexes that couple receptors to cytoskeletal elements and recruit them into cargo vesicles. In this paper, we describe a new trafficking mechanism for the neuronal serotonin 5-HT3A ionotropic channel receptor, in which the role of routing partner is endowed by a functionally interacting purinergic receptor: the P2X2 receptor. This work not only unveils the mechanism by which 5-HT3 receptors can reach their axonal localization required for the control of neurotransmitter release, but also suggests that, in addition to their modulatory role, the family of P2X receptors could have a previously undescribed functional role of trafficking partner proteins dynamically involved in the targeting of other receptors.
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46
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P2 receptors in cancer progression and metastatic spreading. Curr Opin Pharmacol 2016; 29:17-25. [PMID: 27262778 DOI: 10.1016/j.coph.2016.05.001] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2016] [Revised: 04/27/2016] [Accepted: 05/08/2016] [Indexed: 10/21/2022]
Abstract
Tumor microenvironment is nucleoside and nucleotide rich. Adenosine is a key determinant of the highly immunosuppressive tumor interstitium. Extracellular ATP also affects anti-tumor immunity, albeit its effects on host-tumor interaction are incompletely understood. We give here an overview of recent literature covering the role of nucleotide-selective (P2) plasma membrane receptors in tumor growth and progression. P2 receptors are expressed on both host and cancer cells, where depending on the receptor subtype, the inflammatory infiltrate and the tumor cell type they may drive an anti-tumor response or promote tumor progression. It is anticipated that knowledge of the pharmacology, biochemistry and functional activity of the P2 receptors will allow a better understanding of host-tumor interaction and the development of innovative anti-cancer therapy.
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Morales-Perez CL, Noviello CM, Hibbs RE. Manipulation of Subunit Stoichiometry in Heteromeric Membrane Proteins. Structure 2016; 24:797-805. [PMID: 27041595 DOI: 10.1016/j.str.2016.03.004] [Citation(s) in RCA: 96] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Revised: 02/09/2016] [Accepted: 03/04/2016] [Indexed: 01/25/2023]
Abstract
The ability of oligomeric membrane proteins to assemble in different functional ratios of subunits is a common feature across many systems. Recombinant expression of hetero-oligomeric proteins with defined stoichiometries facilitates detailed structural and functional analyses, but remains a major challenge. Here we present two methods for overcoming this challenge: one for rapid virus titration and another for stoichiometry determination. When these methods are coupled, they allow for efficient dissection of the heteromer stoichiometry problem and optimization of homogeneous protein expression. We demonstrate the utility of the methods in a system that to date has proved resistant to atomic-scale structural study, the nicotinic acetylcholine receptor. Leveraging these two methods, we have successfully expressed, purified, and grown diffraction-quality crystals of this challenging target.
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Affiliation(s)
- Claudio L Morales-Perez
- Departments of Neuroscience and Biophysics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Colleen M Noviello
- Departments of Neuroscience and Biophysics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Ryan E Hibbs
- Departments of Neuroscience and Biophysics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.
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48
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Insights into the channel gating of P2X receptors from structures, dynamics and small molecules. Acta Pharmacol Sin 2016; 37:44-55. [PMID: 26725734 DOI: 10.1038/aps.2015.127] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Accepted: 11/02/2015] [Indexed: 12/16/2022] Open
Abstract
P2X receptors, as ATP-gated non-selective trimeric ion channels, are permeable to Na(+), K(+) and Ca(2+). Comparing with other ligand-gated ion channel families, P2X receptors are distinct in their unique gating properties and pathophysiological roles, and have attracted attention as promising drug targets for a variety of diseases, such as neuropathic pain, multiple sclerosis, rheumatoid arthritis and thrombus. Several small molecule inhibitors for distinct P2X subtypes have entered into clinical trials. However, many questions regarding the gating mechanism of P2X remain unsolved. The structural determinations of P2X receptors at the resting and ATP-bound open states revealed that P2X receptor gating is a cooperative allosteric process involving multiple domains, which marks the beginning of the post-structure era of P2X research at atomic level. Here, we review the current knowledge on the structure-function relationship of P2X receptors, depict the whole picture of allosteric changes during the channel gating, and summarize the active sites that may contribute to new strategies for developing novel allosteric drugs targeting P2X receptors.
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49
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Mittal R, Chan B, Grati M, Mittal J, Patel K, Debs LH, Patel AP, Yan D, Chapagain P, Liu XZ. Molecular Structure and Regulation of P2X Receptors With a Special Emphasis on the Role of P2X2 in the Auditory System. J Cell Physiol 2015; 231:1656-70. [PMID: 26627116 DOI: 10.1002/jcp.25274] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2015] [Accepted: 12/01/2015] [Indexed: 12/23/2022]
Abstract
The P2X purinergic receptors are cation-selective channels gated by extracellular adenosine 5'-triphosphate (ATP). These purinergic receptors are found in virtually all mammalian cell types and facilitate a number of important physiological processes. Within the past few years, the characterization of crystal structures of the zebrafish P2X4 receptor in its closed and open states has provided critical insights into the mechanisms of ligand binding and channel activation. Understanding of this gating mechanism has facilitated to design and interpret new modeling and structure-function experiments to better elucidate how different agonists and antagonists can affect the receptor with differing levels of potency. This review summarizes the current knowledge on the structure, activation, allosteric modulators, function, and location of the different P2X receptors. Moreover, an emphasis on the P2X2 receptors has been placed in respect to its role in the auditory system. In particular, the discovery of three missense mutations in P2X2 receptors could become important areas of study in the field of gene therapy to treat progressive and noise-induced hearing loss. J. Cell. Physiol. 231: 1656-1670, 2016. © 2015 Wiley Periodicals, Inc.
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Affiliation(s)
- Rahul Mittal
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, Florida
| | - Brandon Chan
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, Florida
| | - M'hamed Grati
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, Florida
| | - Jeenu Mittal
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, Florida
| | - Kunal Patel
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, Florida
| | - Luca H Debs
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, Florida
| | - Amit P Patel
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, Florida
| | - Denise Yan
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, Florida
| | - Prem Chapagain
- Department of Physics, Florida International University, Miami, Florida.,Biomolecular Science Institute, Florida International University, Miami, Florida
| | - Xue Zhong Liu
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, Florida.,Department of Human Genetics, University of Miami Miller School of Medicine, Miami, Florida.,Department of Biochemistry, University of Miami Miller School of Medicine, Miami, Florida
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50
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Hausmann R, Kless A, Schmalzing G. Key sites for P2X receptor function and multimerization: overview of mutagenesis studies on a structural basis. Curr Med Chem 2015; 22:799-818. [PMID: 25439586 PMCID: PMC4460280 DOI: 10.2174/0929867322666141128163215] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2014] [Revised: 10/20/2014] [Accepted: 11/27/2014] [Indexed: 02/07/2023]
Abstract
P2X receptors constitute a seven-member family (P2X1-7) of extracellular ATP-gated cation
channels of widespread expression. Because P2X receptors have been implicated in neurological, inflammatory
and cardiovascular diseases, they constitute promising drug targets. Since the first P2X cDNA sequences
became available in 1994, numerous site-directed mutagenesis studies have been conducted to disclose
key sites of P2X receptor function and oligomerization. The publication of the 3-Å crystal structures of the zebrafish
P2X4 (zfP2X4) receptor in the homotrimeric apo-closed and ATP-bound open states in 2009 and 2012, respectively, has
ushered a new era by allowing for the interpretation of the wealth of molecular data in terms of specific three-dimensional
models and by paving the way for designing more-decisive experiments. Thanks to these structures, the last five years
have provided invaluable insight into our understanding of the structure and function of the P2X receptor class of ligandgated
ion channels. In this review, we provide an overview of mutagenesis studies of the pre- and post-crystal structure
eras that identified amino acid residues of key importance for ligand binding, channel gating, ion flow, formation of the
pore and the channel gate, and desensitization. In addition, the sites that are involved in the trimerization of P2X receptors
are reviewed based on mutagenesis studies and interface contacts that were predicted by the zfP2X4 crystal structures.
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Affiliation(s)
| | | | - Gunther Schmalzing
- Department of Molecular Pharmacology, Medical Faculty of the RWTH Aachen University, Wendlingweg 2, D-52074 Aachen, Germany.
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