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Daly C, Guseinov AA, Hahn H, Wright A, Tikhonova IG, Thomsen ARB, Plouffe B. β-Arrestin-dependent and -independent endosomal G protein activation by the vasopressin type 2 receptor. eLife 2023; 12:RP87754. [PMID: 37855711 PMCID: PMC10586804 DOI: 10.7554/elife.87754] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2023] Open
Abstract
The vasopressin type 2 receptor (V2R) is an essential G protein-coupled receptor (GPCR) in renal regulation of water homeostasis. Upon stimulation, the V2R activates Gαs and Gαq/11, which is followed by robust recruitment of β-arrestins and receptor internalization into endosomes. Unlike canonical GPCR signaling, the β-arrestin association with the V2R does not terminate Gαs activation, and thus, Gαs-mediated signaling is sustained while the receptor is internalized. Here, we demonstrate that this V2R ability to co-interact with G protein/β-arrestin and promote endosomal G protein signaling is not restricted to Gαs, but also involves Gαq/11. Furthermore, our data imply that β-arrestins potentiate Gαs/Gαq/11 activation at endosomes rather than terminating their signaling. Surprisingly, we found that the V2R internalizes and promote endosomal G protein activation independent of β-arrestins to a minor degree. These new observations challenge the current model of endosomal GPCR signaling and suggest that this event can occur in both β-arrestin-dependent and -independent manners.
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Affiliation(s)
- Carole Daly
- Wellcome-Wolfson Institute for Experimental Medicine, School of Medicine, Dentistry and Biomedical Sciences, Queen’s University BelfastBelfastUnited Kingdom
| | | | - Hyunggu Hahn
- Department of Molecular Pathobiology, New York University College of DentistryNew YorkUnited States
- NYU Pain Research Center, New York University College of DentistryNew YorkUnited States
| | - Adam Wright
- Wellcome-Wolfson Institute for Experimental Medicine, School of Medicine, Dentistry and Biomedical Sciences, Queen’s University BelfastBelfastUnited Kingdom
| | | | - Alex Rojas Bie Thomsen
- Department of Molecular Pathobiology, New York University College of DentistryNew YorkUnited States
- NYU Pain Research Center, New York University College of DentistryNew YorkUnited States
| | - Bianca Plouffe
- Wellcome-Wolfson Institute for Experimental Medicine, School of Medicine, Dentistry and Biomedical Sciences, Queen’s University BelfastBelfastUnited Kingdom
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2
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Daly C, Plouffe B. Gα q signalling from endosomes: A new conundrum. Br J Pharmacol 2023. [PMID: 37740273 DOI: 10.1111/bph.16248] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2023] [Revised: 08/08/2023] [Accepted: 09/13/2023] [Indexed: 09/24/2023] Open
Abstract
G-protein-coupled receptors (GPCRs) constitute the largest family of membrane receptors, and are involved in the transmission of a variety of extracellular stimuli such as hormones, neurotransmitters, light and odorants into intracellular responses. They regulate every aspect of physiology and, for this reason, about one third of all marketed drugs target these receptors. Classically, upon binding to their agonist, GPCRs are thought to activate G-proteins from the plasma membrane and to stop signalling by subsequent desensitisation and endocytosis. However, accumulating evidence indicates that, upon internalisation, some GPCRs can continue to activate G-proteins in endosomes. Importantly, this signalling from endomembranes mediates alternative cellular responses other than signalling at the plasma membrane. Endosomal G-protein signalling and its physiological relevance have been abundantly documented for Gαs - and Gαi -coupled receptors. Recently, some Gαq -coupled receptors have been reported to activate Gαq on endosomes and mediate important cellular processes. However, several questions relative to the series of cellular events required to translate endosomal Gαq activation into cellular responses remain unanswered and constitute a new conundrum. How are these responses in endosomes mediated in the quasi absence of the substrate for the canonical Gαq -activated effector? Is there another effector? Is there another substrate? If so, how does this alternative endosomal effector or substrate produce a downstream signal? This review aims to unravel and discuss these important questions, and proposes possible routes of investigation.
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Affiliation(s)
- Carole Daly
- Wellcome-Wolfson Institute for Experimental Medicine, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast, UK
| | - Bianca Plouffe
- Wellcome-Wolfson Institute for Experimental Medicine, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast, UK
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3
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Daly C, Guseinov AA, Hahn H, Wright A, Tikhonova IG, Thomsen ARB, Plouffe B. β-arrestin-dependent and -independent endosomal G protein activation by the vasopressin type 2 receptor. bioRxiv 2023:2023.04.01.535208. [PMID: 37034816 PMCID: PMC10081317 DOI: 10.1101/2023.04.01.535208] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/19/2023]
Abstract
The vasopressin type 2 receptor (V2R) is an essential GPCR in renal regulation of water homeostasis. Upon stimulation, the V2R activates Gαs and Gαq/11, which is followed by robust recruitment of β-arrestins and receptor internalization into endosomes. Unlike canonical GPCR signaling, the β-arrestin association with the V2R does not terminate Gαs activation, and thus, Gαs-mediated signaling is sustained while the receptor is internalized. Here, we demonstrate that this V2R ability to co-interact with G protein/β-arrestin and promote endosomal G protein signaling is not restricted to Gαs, but also involves Gαq/11. Furthermore, our data implies that β-arrestins potentiate Gαs/Gαq/11 activation at endosomes rather than terminating their signaling. Surprisingly, we found that the V2R internalizes and promote endosomal G protein activation independent of β-arrestins to a minor degree. These new observations challenge the current model of endosomal GPCR signaling and suggest that this event can occur in both β-arrestin-dependent and -independent manners.
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Affiliation(s)
- Carole Daly
- Wellcome-Wolfson Institute for Experimental Medicine, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast, UK
| | | | - Hyunggu Hahn
- Department of Molecular Pathobiology, New York University College of Dentistry, New York, USA
- NYU Pain Research Center, New York University College of Dentistry, New York, USA
| | - Adam Wright
- Wellcome-Wolfson Institute for Experimental Medicine, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast, UK
| | | | - Alex Rojas Bie Thomsen
- Department of Molecular Pathobiology, New York University College of Dentistry, New York, USA
- NYU Pain Research Center, New York University College of Dentistry, New York, USA
| | - Bianca Plouffe
- Wellcome-Wolfson Institute for Experimental Medicine, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast, UK
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4
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Heydenreich FM, Plouffe B, Rizk A, Milic D, Zhou J, Breton B, Le Gouill C, Inoue A, Bouvier M, Veprintsev D. Michaelis-Menten quantification of ligand signalling bias applied to the promiscuous Vasopressin V2 receptor. Mol Pharmacol 2022; 102:139-149. [PMID: 35779859 DOI: 10.1124/molpharm.122.000497] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Accepted: 06/06/2022] [Indexed: 11/22/2022] Open
Abstract
Activation of the G protein-coupled receptors by agonists may result in the activation of one or more G proteins and recruitment of arrestins. The extent of the activation of each of these pathways depends on the intrinsic efficacy of the ligand. Quantification of intrinsic efficacy relative to a reference compound is essential for the development of novel compounds. In the operational model, changes in efficacy can be compensated by changes in the "functional" affinity, resulting in poorly defined values. To separate the effects of ligand affinity from the intrinsic activity of the receptor, we developed a Michaelis-Menten based quantification of G protein activation bias that uses experimentally measured ligand affinities and provides a single measure of ligand efficacy. We used it to evaluate the signalling of a promiscuous model receptor, the Vasopressin V2 receptor (V2R). Using BRET-based biosensors, we show that the V2R engages many different G proteins across all G protein subfamilies in response to its primary endogenous agonist, arginine vasopressin (AVP), including Gs and members of the Gi/o and G12/13 families. These signaling pathways are also activated by the synthetic peptide desmopressin, oxytocin, and the non-mammalian hormone vasotocin. We compared bias quantification using the operational model with Michaelis-Menten based quantification, the latter accurately quantified ligand efficacies despite large difference in ligand affinities. Together, these results showed that V2R is promiscuous in its ability to engage several G proteins and that its' signaling profile is biased by small structural changes in the ligand. Significance Statement By modelling the G protein activation as Michaelis-Menten reaction, we developed a novel way of quantifying signalling bias. V2R activates or at least engages G proteins from all G protein subfamilies, including Gi2, Gz, Gq, G12, and G13. Their relative activation may explain its Gs-independent signalling.
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Affiliation(s)
| | - Bianca Plouffe
- Wellcome-Wolfson Institute for Experimental Medicine, Queen's University Belfast, United Kingdom
| | | | - Dalibor Milic
- Department of Structural and Computational Biology, University of Vienna, Austria
| | - Joris Zhou
- Institute for Research in Immunology and Cancer, University of Montreal, Canada
| | - Billy Breton
- Institute for Research in Immunology and Cancer, University of Montreal, Canada
| | | | | | - Michel Bouvier
- Department of Biochemistry and Molec ular Medicine, University of Montreal, Canada
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5
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Plouffe B, Karamitri A, Flock T, Gallion JM, Houston S, Daly CA, Bonnefond A, Guillaume JL, Le Gouill C, Froguel P, Lichtarge O, Deupi X, Jockers R, Bouvier M. Structural Elements Directing G Proteins and β-Arrestin Interactions with the Human Melatonin Type 2 Receptor Revealed by Natural Variants. ACS Pharmacol Transl Sci 2022; 5:89-101. [PMID: 35846981 PMCID: PMC9281605 DOI: 10.1021/acsptsci.1c00239] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
G protein-coupled receptors (GPCRs) can engage distinct subsets of signaling pathways, but the structural determinants of this functional selectivity remain elusive. The naturally occurring genetic variants of GPCRs, selectively affecting different pathways, offer an opportunity to explore this phenomenon. We previously identified 40 coding variants of the MTNR1B gene encoding the melatonin MT2 receptor (MT2). These mutations differently impact the β-arrestin 2 recruitment, ERK activation, cAMP production, and Gαi1 and Gαz activation. In this study, we combined functional clustering and structural modeling to delineate the molecular features controlling the MT2 functional selectivity. Using non-negative matrix factorization, we analyzed the signaling signatures of the 40 MT2 variants yielding eight clusters defined by unique signaling features and localized in distinct domains of MT2. Using computational homology modeling, we describe how specific mutations can selectively affect the subsets of signaling pathways and offer a proof of principle that natural variants can be used to explore and understand the GPCR functional selectivity.
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Affiliation(s)
- Bianca Plouffe
- Department
of Biochemistry and Molecular Medicine, Université de Montréal, H3T 1J4 Montréal, Québec, Canada,Institute
for Research in Immunology and Cancer, Université
de Montréal, H3T 1J4 Montréal, Québec, Canada,The Wellcome-Wolfson
Institute for Experimental Medicine, Queen’s
University Belfast, BT9 7BL Belfast, U.K.
| | - Angeliki Karamitri
- Université
de Paris, Institut Cochin, INSERM, CNRS, F-75014 Paris, France
| | - Tilman Flock
- Laboratory
of Biomolecular Research, Department of Biology and Chemistry, Paul Scherrer Institute, 5232 Villigen, Switzerland,Department
of Biology, ETH Zürich, 8093 Zürich, Switzerland
| | - Jonathan M. Gallion
- Program
in Structural and Computational Biology and Molecular Biophysics, Baylor College of Medicine, 77030 Houston, Texas, United States
| | - Shane Houston
- The Wellcome-Wolfson
Institute for Experimental Medicine, Queen’s
University Belfast, BT9 7BL Belfast, U.K.
| | - Carole A. Daly
- The Wellcome-Wolfson
Institute for Experimental Medicine, Queen’s
University Belfast, BT9 7BL Belfast, U.K.
| | - Amélie Bonnefond
- Université
de Lille, INSERM/CNRS UMR 1283/8199—EGID, Institut Pasteur
de Lille, CHU de Lille, 59045 Lille, France
| | - Jean-Luc Guillaume
- Université
de Paris, Institut Cochin, INSERM, CNRS, F-75014 Paris, France
| | - Christian Le Gouill
- Institute
for Research in Immunology and Cancer, Université
de Montréal, H3T 1J4 Montréal, Québec, Canada
| | - Phillipe Froguel
- Université
de Lille, INSERM/CNRS UMR 1283/8199—EGID, Institut Pasteur
de Lille, CHU de Lille, 59045 Lille, France
| | - Olivier Lichtarge
- Program
in Structural and Computational Biology and Molecular Biophysics, Baylor College of Medicine, 77030 Houston, Texas, United States,Department
of Molecular and Human Genetics, Baylor
College of Medicine, 77030 Houston, Texas, United States
| | - Xavier Deupi
- Laboratory
of Biomolecular Research, Department of Biology and Chemistry, Paul Scherrer Institute, 5232 Villigen, Switzerland,Condensed
Matter Theory Group, Division of Scientific Computing, Theory, and
Data, Paul Scherrer Institute, 5232 Villigen, Switzerland,. Phone: +41-563103337
| | - Ralf Jockers
- Université
de Paris, Institut Cochin, INSERM, CNRS, F-75014 Paris, France,. Phone: +33-140516434
| | - Michel Bouvier
- Department
of Biochemistry and Molecular Medicine, Université de Montréal, H3T 1J4 Montréal, Québec, Canada,Institute
for Research in Immunology and Cancer, Université
de Montréal, H3T 1J4 Montréal, Québec, Canada,. Phone: 1-514-343-6319
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6
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Hegron A, Huh E, Deupi X, Sokrat B, Gao W, Le Gouill C, Canouil M, Boissel M, Charpentier G, Roussel R, Balkau B, Froguel P, Plouffe B, Bonnefond A, Lichtarge O, Jockers R, Bouvier M. Identification of Key Regions Mediating Human Melatonin Type 1 Receptor Functional Selectivity Revealed by Natural Variants. ACS Pharmacol Transl Sci 2021; 4:1614-1627. [PMID: 34661078 PMCID: PMC8507577 DOI: 10.1021/acsptsci.1c00157] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Indexed: 11/30/2022]
Abstract
Melatonin is a hormone mainly produced by the pineal gland and MT1 is one of the two G protein-coupled receptors (GPCRs) mediating its action. Despite an increasing number of available GPCR crystal structures, the molecular mechanism of activation of a large number of receptors, including MT1, remains poorly understood. The purpose of this study is to elucidate the structural elements involved in the process of MT1's activation using naturally occurring variants affecting its function. Thirty-six nonsynonymous variants, including 34 rare ones, were identified in MTNR1A (encoding MT1) from a cohort of 8687 individuals and their signaling profiles were characterized using Bioluminescence Resonance Energy Transfer-based sensors probing 11 different signaling pathways. Computational analysis of the experimental data allowed us to group the variants in clusters according to their signaling profiles and to analyze the position of each variant in the context of the three-dimensional structure of MT1 to link functional selectivity to structure. MT1 variant signaling profiles revealed three clusters characterized by (1) wild-type-like variants, (2) variants with selective defect of βarrestin-2 recruitment, and (3) severely defective variants on all pathways. Our structural analysis allows us to identify important regions for βarrestin-2 recruitment as well as for Gα12 and Gα15 activation. In addition to identifying MT1 domains differentially controlling the activation of the various signaling effectors, this study illustrates how natural variants can be used as tools to study the molecular mechanisms of receptor activation.
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Affiliation(s)
- Alan Hegron
- Université de Paris, Institut Cochin, CNRS, INSERM, F-75014 Paris, France.,Department of Biochemistry and Molecular Medicine, University de Montréal, Montreal, Quebec, H3T 1J4 Canada.,Institute for Research in Immunology and Cancer, University of Montreal, Montreal, Quebec, H3T 1J4 Canada
| | - Eunna Huh
- Department of Pharmacology and Chemical Biology, Baylor College of Medicine, Houston, Texas 77030, United States of America
| | - Xavier Deupi
- Laboratory of Biomolecular Research, Paul Scherrer Institute (PSI), 5232 Villigen, Switzerland.,Condensed Matter Theory group, Paul Scherrer Institute (PSI), 5232 Villigen, Switzerland
| | - Badr Sokrat
- Department of Biochemistry and Molecular Medicine, University de Montréal, Montreal, Quebec, H3T 1J4 Canada.,Institute for Research in Immunology and Cancer, University of Montreal, Montreal, Quebec, H3T 1J4 Canada
| | - Wenwen Gao
- Université de Paris, Institut Cochin, CNRS, INSERM, F-75014 Paris, France
| | - Christian Le Gouill
- Institute for Research in Immunology and Cancer, University of Montreal, Montreal, Quebec, H3T 1J4 Canada
| | - Mickaël Canouil
- Inserm UMR1283, CNRS UMR8199, European Genomic Institute for Diabetes (EGID), Institut Pasteur de Lille, Lille, 59000, France.,University of Lille, Lille University Hospital, Lille, 59000, France
| | - Mathilde Boissel
- Inserm UMR1283, CNRS UMR8199, European Genomic Institute for Diabetes (EGID), Institut Pasteur de Lille, Lille, 59000, France.,University of Lille, Lille University Hospital, Lille, 59000, France
| | - Guillaume Charpentier
- Centre d'Étude et de Recherche pour l'Intensification du Traitement du Diabète, 91000, Evry, France
| | - Ronan Roussel
- Department of Diabetology Endocrinology Nutrition, Hôpital Bichat, DHU FIRE, Assistance Publique Hôpitaux de Paris, 75004 Paris, France.,Inserm U1138, Centre de Recherche des Cordeliers, 75006 Paris, France.,UFR de Médecine, University Paris Diderot, Sorbonne Paris Cité, 75006 Paris, France
| | - Beverley Balkau
- Inserm U1018, Center for Research in Epidemiology and Population Health, 94805 Villejuif, France.,University Paris-Saclay, University Paris-Sud, 94270 Villejuif, France
| | - Philippe Froguel
- Inserm UMR1283, CNRS UMR8199, European Genomic Institute for Diabetes (EGID), Institut Pasteur de Lille, Lille, 59000, France.,University of Lille, Lille University Hospital, Lille, 59000, France.,Department of Metabolism, Imperial College London, London, W12 0NN, United Kingdom
| | - Bianca Plouffe
- Department of Biochemistry and Molecular Medicine, University de Montréal, Montreal, Quebec, H3T 1J4 Canada.,Institute for Research in Immunology and Cancer, University of Montreal, Montreal, Quebec, H3T 1J4 Canada
| | - Amélie Bonnefond
- Inserm UMR1283, CNRS UMR8199, European Genomic Institute for Diabetes (EGID), Institut Pasteur de Lille, Lille, 59000, France.,University of Lille, Lille University Hospital, Lille, 59000, France.,Department of Metabolism, Imperial College London, London, W12 0NN, United Kingdom
| | - Olivier Lichtarge
- Department of Pharmacology and Chemical Biology, Baylor College of Medicine, Houston, Texas 77030, United States of America.,Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas 77030, United States
| | - Ralf Jockers
- Université de Paris, Institut Cochin, CNRS, INSERM, F-75014 Paris, France
| | - Michel Bouvier
- Department of Biochemistry and Molecular Medicine, University de Montréal, Montreal, Quebec, H3T 1J4 Canada.,Institute for Research in Immunology and Cancer, University of Montreal, Montreal, Quebec, H3T 1J4 Canada
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7
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Brouwers B, de Oliveira EM, Marti-Solano M, Monteiro FBF, Laurin SA, Keogh JM, Henning E, Bounds R, Daly CA, Houston S, Ayinampudi V, Wasiluk N, Clarke D, Plouffe B, Bouvier M, Babu MM, Farooqi IS, Mokrosiński J. Human MC4R variants affect endocytosis, trafficking and dimerization revealing multiple cellular mechanisms involved in weight regulation. Cell Rep 2021; 34:108862. [PMID: 33761344 PMCID: PMC7994375 DOI: 10.1016/j.celrep.2021.108862] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Revised: 01/29/2021] [Accepted: 02/19/2021] [Indexed: 12/13/2022] Open
Abstract
The Melanocortin-4 Receptor (MC4R) plays a pivotal role in energy homeostasis. We used human MC4R mutations associated with an increased or decreased risk of obesity to dissect mechanisms that regulate MC4R function. Most obesity-associated mutations impair trafficking to the plasma membrane (PM), whereas obesity-protecting mutations either accelerate recycling to the PM or decrease internalization, resulting in enhanced signaling. MC4R mutations that do not affect canonical Gαs protein-mediated signaling, previously considered to be non-pathogenic, nonetheless disrupt agonist-induced internalization, β-arrestin recruitment, and/or coupling to Gαs, establishing their causal role in severe obesity. Structural mapping reveals ligand-accessible sites by which MC4R couples to effectors and residues involved in the homodimerization of MC4R, which is disrupted by multiple obesity-associated mutations. Human genetic studies reveal that endocytosis, intracellular trafficking, and homodimerization regulate MC4R function to a level that is physiologically relevant, supporting the development of chaperones, agonists, and allosteric modulators of MC4R for weight loss therapy.
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Affiliation(s)
- Bas Brouwers
- University of Cambridge Metabolic Research Laboratories and NIHR Cambridge Biomedical Research Centre, Wellcome-MRC Institute of Metabolic Science, Addenbrooke's Hospital, Cambridge CB2 0QQ, UK
| | - Edson Mendes de Oliveira
- University of Cambridge Metabolic Research Laboratories and NIHR Cambridge Biomedical Research Centre, Wellcome-MRC Institute of Metabolic Science, Addenbrooke's Hospital, Cambridge CB2 0QQ, UK
| | | | - Fabiola B F Monteiro
- University of Cambridge Metabolic Research Laboratories and NIHR Cambridge Biomedical Research Centre, Wellcome-MRC Institute of Metabolic Science, Addenbrooke's Hospital, Cambridge CB2 0QQ, UK
| | - Suli-Anne Laurin
- Institute for Research in Immunology and Cancer, Department of Biochemistry and Molecular Medicine, Université de Montréal, Montréal, QC H3T 1J4, Canada
| | - Julia M Keogh
- University of Cambridge Metabolic Research Laboratories and NIHR Cambridge Biomedical Research Centre, Wellcome-MRC Institute of Metabolic Science, Addenbrooke's Hospital, Cambridge CB2 0QQ, UK
| | - Elana Henning
- University of Cambridge Metabolic Research Laboratories and NIHR Cambridge Biomedical Research Centre, Wellcome-MRC Institute of Metabolic Science, Addenbrooke's Hospital, Cambridge CB2 0QQ, UK
| | - Rebecca Bounds
- University of Cambridge Metabolic Research Laboratories and NIHR Cambridge Biomedical Research Centre, Wellcome-MRC Institute of Metabolic Science, Addenbrooke's Hospital, Cambridge CB2 0QQ, UK
| | - Carole A Daly
- Wellcome-Wolfson Institute for Experimental Medicine, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast BT9 7BL, UK
| | - Shane Houston
- Wellcome-Wolfson Institute for Experimental Medicine, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast BT9 7BL, UK
| | - Vikram Ayinampudi
- University of Cambridge Metabolic Research Laboratories and NIHR Cambridge Biomedical Research Centre, Wellcome-MRC Institute of Metabolic Science, Addenbrooke's Hospital, Cambridge CB2 0QQ, UK
| | - Natalia Wasiluk
- University of Cambridge Metabolic Research Laboratories and NIHR Cambridge Biomedical Research Centre, Wellcome-MRC Institute of Metabolic Science, Addenbrooke's Hospital, Cambridge CB2 0QQ, UK
| | - David Clarke
- University of Cambridge Metabolic Research Laboratories and NIHR Cambridge Biomedical Research Centre, Wellcome-MRC Institute of Metabolic Science, Addenbrooke's Hospital, Cambridge CB2 0QQ, UK
| | - Bianca Plouffe
- Wellcome-Wolfson Institute for Experimental Medicine, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast BT9 7BL, UK
| | - Michel Bouvier
- Institute for Research in Immunology and Cancer, Department of Biochemistry and Molecular Medicine, Université de Montréal, Montréal, QC H3T 1J4, Canada
| | - M Madan Babu
- MRC Laboratory of Molecular Biology, Cambridge, UK; Department of Structural Biology and Center for Data Driven Discovery, St Jude Children's Research Hospital, Memphis, TN, USA
| | - I Sadaf Farooqi
- University of Cambridge Metabolic Research Laboratories and NIHR Cambridge Biomedical Research Centre, Wellcome-MRC Institute of Metabolic Science, Addenbrooke's Hospital, Cambridge CB2 0QQ, UK.
| | - Jacek Mokrosiński
- University of Cambridge Metabolic Research Laboratories and NIHR Cambridge Biomedical Research Centre, Wellcome-MRC Institute of Metabolic Science, Addenbrooke's Hospital, Cambridge CB2 0QQ, UK
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8
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Imam A, Winnebeck EC, Buchholz N, Froguel P, Bonnefond A, Solimena M, Ivanova A, Bouvier M, Plouffe B, Charpentier G, Karamitri A, Jockers R, Roenneberg T, Vetter C. Circadian, Sleep and Caloric Intake Phenotyping in Type 2 Diabetes Patients With Rare Melatonin Receptor 2 Mutations and Controls: A Pilot Study. Front Physiol 2020; 11:564140. [PMID: 33162895 PMCID: PMC7583701 DOI: 10.3389/fphys.2020.564140] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Accepted: 09/07/2020] [Indexed: 01/27/2023] Open
Abstract
Background Melatonin modulates circadian rhythms in physiology and sleep initiation. Genetic variants of the MTNR1B locus, encoding the melatonin MT2 receptor, have been associated with increased type 2 diabetes (T2D) risk. Carriers of the common intronic MTNR1B rs10830963 T2D risk variant have modified sleep and circadian traits such as changes of the melatonin profile. However, it is currently unknown whether rare variants in the MT2 coding region are also associated with altered sleep and circadian phenotypes, including meal timing. Materials and Methods In this pilot study, 28 individuals [50% male; 46–82 years old; 50% with rare MT2 mutations (T2D MT2)] wore actigraphy devices and filled out daily food logs for 4 weeks. We computed circadian, sleep, and caloric intake phenotypes, including sleep duration, timing, and regularity [assessed by the Sleep Regularity Index (SRI)]; composite phase deviations (CPD) as well a sleep timing-based proxy for circadian misalignment; and caloric intake patterns throughout the day. Using regression analyses, we estimated age- and sex-adjusted mean differences (MD) and 95% confidence intervals (95%CI) between the two patient groups. Secondary analyses also compare T2D MT2 to 15 healthy controls. Results Patients with rare MT2 mutations had a later sleep onset (MD = 1.23, 95%CI = 0.42;2.04), and midsleep time (MD = 0.91, 95%CI = 0.12;1.70), slept more irregularly (MD in SRI = −8.98, 95%CI = −16.36;−1.60), had higher levels of behavioral circadian misalignment (MD in CPD = 1.21, 95%CI = 0.51;1.92), were more variable in regard to duration between first caloric intake and average sleep offset (MD = 1.08, 95%CI = 0.07;2.08), and had more caloric episodes in a 24 h day (MD = 1.08, 95%CI = 0.26;1.90), in comparison to T2D controls. Secondary analyses showed similar patterns between T2D MT2 and non-diabetic controls. Conclusion This pilot study suggests that compared to diabetic controls, T2D MT2 patients display a number of adverse sleep, circadian, and caloric intake phenotypes, including more irregular behavioral timing. A prospective study is needed to determine the role of these behavioral phenotypes in T2D onset and severity, especially in view of rare MT2 mutations.
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Affiliation(s)
- Akram Imam
- Department of Integrative Physiology, University of Colorado Boulder, Boulder, CO, United States
| | - Eva C Winnebeck
- Institute of Medical Psychology, Ludwig Maximilian University, Munich, Germany
| | - Nina Buchholz
- Institute of Medical Psychology, Ludwig Maximilian University, Munich, Germany
| | - Philippe Froguel
- Inserm UMR1283, CNRS UMR8199, European Genomic Institute for Diabetes (EGID), Institut Pasteur de Lille, University of Lille, Lille University Hospital, Lille, France.,Department of Metabolism, Imperial College London, London, United Kingdom
| | - Amélie Bonnefond
- Inserm UMR1283, CNRS UMR8199, European Genomic Institute for Diabetes (EGID), Institut Pasteur de Lille, University of Lille, Lille University Hospital, Lille, France.,Department of Metabolism, Imperial College London, London, United Kingdom
| | - Michele Solimena
- Paul Langerhans Institute Dresden of the Helmholtz Center Munich at the Technische Universität Dresden, Dresden, Germany
| | - Anna Ivanova
- Paul Langerhans Institute Dresden of the Helmholtz Center Munich at the Technische Universität Dresden, Dresden, Germany
| | - Michel Bouvier
- Department of Biochemistry and Molecular Medicine, Institute for Research in Immunology and Cancer, Université de Montréal, Montréal, QC, Canada
| | - Bianca Plouffe
- Department of Biochemistry and Molecular Medicine, Institute for Research in Immunology and Cancer, Université de Montréal, Montréal, QC, Canada.,School of Medicine, Dentistry and Biomedical Sciences, Wellcome-Wolfson Institute for Experimental Medicine, Queen's University Belfast, Belfast, United Kingdom
| | - Guillaume Charpentier
- Centre d'Études et de Recherches pour l'Intensification du Traitement du Diabète (CERITD), Sud-Francilien Hospital, Corbeil-Essonnes, France
| | | | - Ralf Jockers
- Université de Paris, Institut Cochin, INSERM, CNRS, Paris, France
| | - Till Roenneberg
- Institute of Medical Psychology, Ludwig Maximilian University, Munich, Germany
| | - Céline Vetter
- Department of Integrative Physiology, University of Colorado Boulder, Boulder, CO, United States.,Institute of Medical Psychology, Ludwig Maximilian University, Munich, Germany
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9
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Plouffe B, Thomsen ARB, Irannejad R. Emerging Role of Compartmentalized G Protein-Coupled Receptor Signaling in the Cardiovascular Field. ACS Pharmacol Transl Sci 2020; 3:221-236. [PMID: 32296764 PMCID: PMC7155194 DOI: 10.1021/acsptsci.0c00006] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2020] [Indexed: 02/06/2023]
Abstract
G protein-coupled receptors (GPCRs) are cell surface receptors that for many years have been considered to function exclusively at the plasma membrane, where they bind to extracellular ligands and activate G protein signaling cascades. According to the conventional model, these signaling events are rapidly terminated by β-arrestin (β-arr) recruitment to the activated GPCR resulting in signal desensitization and receptor internalization. However, during the past decade, emerging evidence suggest that many GPCRs can continue to activate G proteins from intracellular compartments after they have been internalized. G protein signaling from intracellular compartments is in general more sustained compared to G protein signaling at the plasma membrane. Notably, the particular location closer to the nucleus is beneficial for selective cellular functions such as regulation of gene transcription. Here, we review key GPCRs that undergo compartmentalized G protein signaling and discuss molecular considerations and requirements for this signaling to occur. Our main focus will be on receptors involved in the regulation of important physiological and pathological cardiovascular functions. We also discuss how sustained G protein activation from intracellular compartments may be involved in cellular functions that are distinct from functions regulated by plasma membrane G protein signaling, and the corresponding significance in cardiovascular physiology.
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Affiliation(s)
- Bianca Plouffe
- Wellcome-Wolfson Institute for Experimental Medicine, Queen's University Belfast, Belfast BT9 7BL, United Kingdom
| | - Alex R B Thomsen
- Department of Basic Science and Craniofacial Biology, NYU College of Dentistry, New York, New York 10010, United States
| | - Roshanak Irannejad
- Department of Biochemistry and Biophysics, Cardiovascular Research Institute, University of California, San Francisco, California 94158, United States
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10
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Imam A, Winnebeck E, Buchholz N, Froguel P, Bonnefond A, Solimena M, Ivanova A, Bouvier M, Plouffe B, Charpentier G, Karamitri A, Jockers R, Roenneberg T, Vetter C. Functional circadian and sleep phenotyping of type 2 diabetes patients with melatonin receptor 2 mutations and controls: a pilot study. Sleep Med 2019. [DOI: 10.1016/j.sleep.2019.11.460] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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11
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Luttrell LM, Wang J, Plouffe B, Smith JS, Yamani L, Kaur S, Jean-Charles PY, Gauthier C, Lee MH, Pani B, Kim J, Ahn S, Rajagopal S, Reiter E, Bouvier M, Shenoy SK, Laporte SA, Rockman HA, Lefkowitz RJ. Manifold roles of β-arrestins in GPCR signaling elucidated with siRNA and CRISPR/Cas9. Sci Signal 2018; 11:11/549/eaat7650. [PMID: 30254056 DOI: 10.1126/scisignal.aat7650] [Citation(s) in RCA: 132] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
G protein-coupled receptors (GPCRs) use diverse mechanisms to regulate the mitogen-activated protein kinases ERK1/2. β-Arrestins (βArr1/2) are ubiquitous inhibitors of G protein signaling, promoting GPCR desensitization and internalization and serving as scaffolds for ERK1/2 activation. Studies using CRISPR/Cas9 to delete βArr1/2 and G proteins have cast doubt on the role of β-arrestins in activating specific pools of ERK1/2. We compared the effects of siRNA-mediated knockdown of βArr1/2 and reconstitution with βArr1/2 in three different parental and CRISPR-derived βArr1/2 knockout HEK293 cell pairs to assess the effect of βArr1/2 deletion on ERK1/2 activation by four Gs-coupled GPCRs. In all parental lines with all receptors, ERK1/2 stimulation was reduced by siRNAs specific for βArr2 or βArr1/2. In contrast, variable effects were observed with CRISPR-derived cell lines both between different lines and with activation of different receptors. For β2 adrenergic receptors (β2ARs) and β1ARs, βArr1/2 deletion increased, decreased, or had no effect on isoproterenol-stimulated ERK1/2 activation in different CRISPR clones. ERK1/2 activation by the vasopressin V2 and follicle-stimulating hormone receptors was reduced in these cells but was enhanced by reconstitution with βArr1/2. Loss of desensitization and receptor internalization in CRISPR βArr1/2 knockout cells caused β2AR-mediated stimulation of ERK1/2 to become more dependent on G proteins, which was reversed by reintroducing βArr1/2. These data suggest that βArr1/2 function as a regulatory hub, determining the balance between mechanistically different pathways that result in activation of ERK1/2, and caution against extrapolating results obtained from βArr1/2- or G protein-deleted cells to GPCR behavior in native systems.
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Affiliation(s)
- Louis M Luttrell
- Department of Medicine, Medical University of South Carolina, Charleston, SC 29425, USA.,Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, SC 29425, USA.,Research Service of the Ralph H. Johnson Veterans Affairs Medical Center, Charleston, SC 29401, USA
| | - Jialu Wang
- Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA
| | - Bianca Plouffe
- Department of Biochemistry and Molecular Medicine, Institute for Research in Immunology and Cancer, University of Montreal, Montreal, Quebec H3C IJ4, Canada
| | - Jeffrey S Smith
- Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA.,Department of Biochemistry, Duke University Medical Center, Durham, NC 27710, USA
| | - Lama Yamani
- Department of Medicine, Research Institute of the McGill University Health Center, McGill University, Montreal, Quebec H4A 3J1, Canada
| | - Suneet Kaur
- Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA
| | | | - Christophe Gauthier
- Physiologie de la Reproduction et des Comportements, Institut National de la Recherche Agronomique, CNRS, Université de Tours, 37380 Nouzilly, France
| | - Mi-Hye Lee
- Department of Medicine, Medical University of South Carolina, Charleston, SC 29425, USA
| | - Biswaranjan Pani
- Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA
| | - Jihee Kim
- Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA
| | - Seungkirl Ahn
- Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA
| | - Sudarshan Rajagopal
- Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA.,Department of Biochemistry, Duke University Medical Center, Durham, NC 27710, USA
| | - Eric Reiter
- Physiologie de la Reproduction et des Comportements, Institut National de la Recherche Agronomique, CNRS, Université de Tours, 37380 Nouzilly, France
| | - Michel Bouvier
- Department of Biochemistry and Molecular Medicine, Institute for Research in Immunology and Cancer, University of Montreal, Montreal, Quebec H3C IJ4, Canada
| | - Sudha K Shenoy
- Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA.,Department of Cell Biology, Duke University Medical Center, Durham, NC 27710, USA
| | - Stéphane A Laporte
- Department of Medicine, Research Institute of the McGill University Health Center, McGill University, Montreal, Quebec H4A 3J1, Canada
| | - Howard A Rockman
- Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA.,Department of Cell Biology, Duke University Medical Center, Durham, NC 27710, USA.,Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27710, USA
| | - Robert J Lefkowitz
- Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA. .,Department of Biochemistry, Duke University Medical Center, Durham, NC 27710, USA.,Howard Hughes Medical Institute, Duke University Medical Center, Durham, NC 27710, USA
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12
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Karamitri A, Plouffe B, Bonnefond A, Chen M, Gallion J, Guillaume JL, Hegron A, Boissel M, Canouil M, Langenberg C, Wareham NJ, Le Gouill C, Lukasheva V, Lichtarge O, Froguel P, Bouvier M, Jockers R. Type 2 diabetes-associated variants of the MT 2 melatonin receptor affect distinct modes of signaling. Sci Signal 2018; 11:11/545/eaan6622. [PMID: 30154102 DOI: 10.1126/scisignal.aan6622] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Melatonin is produced during the night and regulates sleep and circadian rhythms. Loss-of-function variants in MTNR1B, which encodes the melatonin receptor MT2, a G protein-coupled receptor (GPCR), are associated with an increased risk of type 2 diabetes (T2D). To identify specific T2D-associated signaling pathway(s), we profiled the signaling output of 40 MT2 variants by monitoring spontaneous (ligand-independent) and melatonin-induced activation of multiple signaling effectors. Genetic association analysis showed that defects in the melatonin-induced activation of Gαi1 and Gαz proteins and in spontaneous β-arrestin2 recruitment to MT2 were the most statistically significantly associated with an increased T2D risk. Computational variant impact prediction by in silico evolutionary lineage analysis strongly correlated with the measured phenotypic effect of each variant, providing a predictive tool for future studies on GPCR variants. Together, this large-scale functional study provides an operational framework for the postgenomic analysis of the multiple GPCR variants present in the human population. The association of T2D risk with signaling pathway-specific defects opens avenues for pathway-specific personalized therapeutic intervention and reveals the potential relevance of MT2 function during the day, when melatonin is undetectable, but spontaneous activity of the receptor occurs.
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Affiliation(s)
- Angeliki Karamitri
- Inserm, U1016, Institut Cochin, Paris, France.,CNRS UMR 8104, Paris, France.,Université Paris Descartes, Paris, France
| | - Bianca Plouffe
- Institute for Research in Immunology and Cancer and Department of Biochemistry and Molecular Medicine, Université de Montréal, Montreal, Québec H3C 3J7, Canada
| | - Amélie Bonnefond
- Université Lille, CNRS UMR 8199-EGID, Institut Pasteur de Lille, Lille, France
| | - Min Chen
- Inserm, U1016, Institut Cochin, Paris, France.,CNRS UMR 8104, Paris, France.,Université Paris Descartes, Paris, France
| | - Jonathan Gallion
- Structural Computational Biology and Molecular Biophysics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Jean-Luc Guillaume
- Inserm, U1016, Institut Cochin, Paris, France.,CNRS UMR 8104, Paris, France.,Université Paris Descartes, Paris, France
| | - Alan Hegron
- Inserm, U1016, Institut Cochin, Paris, France.,CNRS UMR 8104, Paris, France.,Université Paris Descartes, Paris, France
| | - Mathilde Boissel
- Université Lille, CNRS UMR 8199-EGID, Institut Pasteur de Lille, Lille, France
| | - Mickaël Canouil
- Université Lille, CNRS UMR 8199-EGID, Institut Pasteur de Lille, Lille, France
| | - Claudia Langenberg
- Medical Research Council (MRC) Epidemiology Unit, University of Cambridge School of Clinical Medicine, Cambridge CB2 0QQ, UK
| | - Nicholas J Wareham
- Medical Research Council (MRC) Epidemiology Unit, University of Cambridge School of Clinical Medicine, Cambridge CB2 0QQ, UK
| | - Christian Le Gouill
- Institute for Research in Immunology and Cancer and Department of Biochemistry and Molecular Medicine, Université de Montréal, Montreal, Québec H3C 3J7, Canada
| | - Viktoria Lukasheva
- Institute for Research in Immunology and Cancer and Department of Biochemistry and Molecular Medicine, Université de Montréal, Montreal, Québec H3C 3J7, Canada
| | - Olivier Lichtarge
- Structural Computational Biology and Molecular Biophysics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Philippe Froguel
- Université Lille, CNRS UMR 8199-EGID, Institut Pasteur de Lille, Lille, France. .,Department of Genomics of Common Disease, School of Public Health, Imperial College London, Hammersmith Hospital, W12 0NN London, UK
| | - Michel Bouvier
- Institute for Research in Immunology and Cancer and Department of Biochemistry and Molecular Medicine, Université de Montréal, Montreal, Québec H3C 3J7, Canada.
| | - Ralf Jockers
- Inserm, U1016, Institut Cochin, Paris, France. .,CNRS UMR 8104, Paris, France.,Université Paris Descartes, Paris, France
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13
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Plouffe B, Karamitri A, Flock T, Gallion JM, Bonnefond A, Guillaume J, Le Gouill C, Froguel P, Lichtarge O, Deupi X, Jockers R, Bouvier M. Identification of residues in human melatonin type 2 receptor involved in signaling selectivity or general signal transmission using natural variants. FASEB J 2018. [DOI: 10.1096/fasebj.2018.32.1_supplement.555.9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
| | | | | | | | | | | | | | | | | | | | - Ralf Jockers
- Institut CochinUniversité Paris DescartesParisFrance
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14
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Cahill T, Thomsen A, Plouffe B, Bouvier M, Lefkowitz R. LB987 New insights into gpcr-transducer coupling. J Invest Dermatol 2017. [DOI: 10.1016/j.jid.2017.07.067] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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15
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Payne R, Halik L, Ma J, Zhang H, Zhang J, Conklin J, Gaylord M, Yokoyama K, Bahrainy Y, Ozgen N, Balderson J, Chase A, Gorman R, Plouffe B, Deflippi C. P2754Performance evaluation of the siemens advia centaur high sensitivity troponin i assay. Eur Heart J 2017. [DOI: 10.1093/eurheartj/ehx502.p2754] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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16
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Möller D, Banerjee A, Uzuneser TC, Skultety M, Huth T, Plouffe B, Hübner H, Alzheimer C, Friedland K, Müller CP, Bouvier M, Gmeiner P. Discovery of G Protein-Biased Dopaminergics with a Pyrazolo[1,5-a]pyridine Substructure. J Med Chem 2017; 60:2908-2929. [DOI: 10.1021/acs.jmedchem.6b01857] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Dorothee Möller
- Department
of Chemistry and Pharmacy, Medicinal Chemistry, Friedrich-Alexander University Erlangen-Nürnberg, Schuhstraße 19, 91052 Erlangen, Germany
| | - Ashutosh Banerjee
- Department
of Chemistry and Pharmacy, Medicinal Chemistry, Friedrich-Alexander University Erlangen-Nürnberg, Schuhstraße 19, 91052 Erlangen, Germany
| | - Taygun C. Uzuneser
- Department
of Psychiatry and Psychotherapy, Friedrich-Alexander University Erlangen-Nürnberg, Schwabachanlage 6, 91054 Erlangen, Germany
| | - Marika Skultety
- Department
of Chemistry and Pharmacy, Medicinal Chemistry, Friedrich-Alexander University Erlangen-Nürnberg, Schuhstraße 19, 91052 Erlangen, Germany
| | - Tobias Huth
- Institute
of Physiology and Pathophysiology, Friedrich-Alexander University Erlangen-Nürnberg, Universitätsstraße 17, 91054 Erlangen, Germany
| | - Bianca Plouffe
- Institute
for Research in Immunology and Cancer (IRIC), Department of Biochemistry
and Molecular Medicine, University of Montreal, Québec, Canada H3C 1J4
| | - Harald Hübner
- Department
of Chemistry and Pharmacy, Medicinal Chemistry, Friedrich-Alexander University Erlangen-Nürnberg, Schuhstraße 19, 91052 Erlangen, Germany
| | - Christian Alzheimer
- Institute
of Physiology and Pathophysiology, Friedrich-Alexander University Erlangen-Nürnberg, Universitätsstraße 17, 91054 Erlangen, Germany
| | - Kristina Friedland
- Department
of Chemistry and Pharmacy, Molecular and Clinical Pharmacy, Friedrich-Alexander University Erlangen-Nürnberg, Cauerstraße 4, 91058 Erlangen, Germany
| | - Christian P. Müller
- Department
of Psychiatry and Psychotherapy, Friedrich-Alexander University Erlangen-Nürnberg, Schwabachanlage 6, 91054 Erlangen, Germany
| | - Michel Bouvier
- Institute
for Research in Immunology and Cancer (IRIC), Department of Biochemistry
and Molecular Medicine, University of Montreal, Québec, Canada H3C 1J4
| | - Peter Gmeiner
- Department
of Chemistry and Pharmacy, Medicinal Chemistry, Friedrich-Alexander University Erlangen-Nürnberg, Schuhstraße 19, 91052 Erlangen, Germany
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17
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Stallaert W, van der Westhuizen ET, Schönegge AM, Plouffe B, Hogue M, Lukashova V, Inoue A, Ishida S, Aoki J, Le Gouill C, Bouvier M. Purinergic Receptor Transactivation by the β2-Adrenergic Receptor Increases Intracellular Ca 2+ in Nonexcitable Cells. Mol Pharmacol 2017; 91:533-544. [PMID: 28280061 DOI: 10.1124/mol.116.106419] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2016] [Accepted: 03/06/2017] [Indexed: 12/11/2022] Open
Abstract
The β2 adrenergic receptor (β2AR) increases intracellular Ca2+ in a variety of cell types. By combining pharmacological and genetic manipulations, we reveal a novel mechanism through which the β2AR promotes Ca2+ mobilization (pEC50 = 7.32 ± 0.10) in nonexcitable human embryonic kidney (HEK)293S cells. Downregulation of Gs with sustained cholera toxin pretreatment and the use of Gs-null HEK293 (∆Gs-HEK293) cells generated using the clustered regularly interspaced short palindromic repeat-associated protein-9 nuclease (CRISPR/Cas9) system, combined with pharmacological modulation of cAMP formation, revealed a Gs-dependent but cAMP-independent increase in intracellular Ca2+ following β2AR stimulation. The increase in cytoplasmic Ca2+ was inhibited by P2Y purinergic receptor antagonists as well as a dominant-negative mutant form of Gq, a Gq-selective inhibitor, and an inositol 1,4,5-trisphosphate (IP3) receptor antagonist, suggesting a role for this Gq-coupled receptor family downstream of the β2AR activation. Consistent with this mechanism, β2AR stimulation promoted the extracellular release of ATP, and pretreatment with apyrase inhibited the β2AR-promoted Ca2+ mobilization. Together, these data support a model whereby the β2AR stimulates a Gs-dependent release of ATP, which transactivates Gq-coupled P2Y receptors through an inside-out mechanism, leading to a Gq- and IP3-dependent Ca2+ mobilization from intracellular stores. Given that β2AR and P2Y receptors are coexpressed in various tissues, this novel signaling paradigm could be physiologically important and have therapeutic implications. In addition, this study reports the generation and validation of HEK293 cells deleted of Gs using the CRISPR/Cas9 genome editing technology that will undoubtedly be powerful tools to study Gs-dependent signaling.
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Affiliation(s)
- Wayne Stallaert
- Department of Biochemistry (W.S., E.T.v.d.W., A.-M.S., B.P., M.B.) and Institute for Research in Immunology and Cancer (W.S., E.T.v.d.W., A.-M.S., B.P., M.H., V.L., C.L.G., M.B.), Université de Montréal, Montréal, QC, Canada; Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Miyagi, Japan (A.I., S.I., J.A.); Japan Science and Technology Agency, Precursory Research for Embryonic Science and Technology, Kawaguchi, Saitama, Japan (A.I.); and Japan Agency for Medical Research and Development, Core Research for Evolutional Science and Technology, Chiyoda-ku, Tokyo, Japan (J.A.)
| | - Emma T van der Westhuizen
- Department of Biochemistry (W.S., E.T.v.d.W., A.-M.S., B.P., M.B.) and Institute for Research in Immunology and Cancer (W.S., E.T.v.d.W., A.-M.S., B.P., M.H., V.L., C.L.G., M.B.), Université de Montréal, Montréal, QC, Canada; Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Miyagi, Japan (A.I., S.I., J.A.); Japan Science and Technology Agency, Precursory Research for Embryonic Science and Technology, Kawaguchi, Saitama, Japan (A.I.); and Japan Agency for Medical Research and Development, Core Research for Evolutional Science and Technology, Chiyoda-ku, Tokyo, Japan (J.A.)
| | - Anne-Marie Schönegge
- Department of Biochemistry (W.S., E.T.v.d.W., A.-M.S., B.P., M.B.) and Institute for Research in Immunology and Cancer (W.S., E.T.v.d.W., A.-M.S., B.P., M.H., V.L., C.L.G., M.B.), Université de Montréal, Montréal, QC, Canada; Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Miyagi, Japan (A.I., S.I., J.A.); Japan Science and Technology Agency, Precursory Research for Embryonic Science and Technology, Kawaguchi, Saitama, Japan (A.I.); and Japan Agency for Medical Research and Development, Core Research for Evolutional Science and Technology, Chiyoda-ku, Tokyo, Japan (J.A.)
| | - Bianca Plouffe
- Department of Biochemistry (W.S., E.T.v.d.W., A.-M.S., B.P., M.B.) and Institute for Research in Immunology and Cancer (W.S., E.T.v.d.W., A.-M.S., B.P., M.H., V.L., C.L.G., M.B.), Université de Montréal, Montréal, QC, Canada; Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Miyagi, Japan (A.I., S.I., J.A.); Japan Science and Technology Agency, Precursory Research for Embryonic Science and Technology, Kawaguchi, Saitama, Japan (A.I.); and Japan Agency for Medical Research and Development, Core Research for Evolutional Science and Technology, Chiyoda-ku, Tokyo, Japan (J.A.)
| | - Mireille Hogue
- Department of Biochemistry (W.S., E.T.v.d.W., A.-M.S., B.P., M.B.) and Institute for Research in Immunology and Cancer (W.S., E.T.v.d.W., A.-M.S., B.P., M.H., V.L., C.L.G., M.B.), Université de Montréal, Montréal, QC, Canada; Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Miyagi, Japan (A.I., S.I., J.A.); Japan Science and Technology Agency, Precursory Research for Embryonic Science and Technology, Kawaguchi, Saitama, Japan (A.I.); and Japan Agency for Medical Research and Development, Core Research for Evolutional Science and Technology, Chiyoda-ku, Tokyo, Japan (J.A.)
| | - Viktoria Lukashova
- Department of Biochemistry (W.S., E.T.v.d.W., A.-M.S., B.P., M.B.) and Institute for Research in Immunology and Cancer (W.S., E.T.v.d.W., A.-M.S., B.P., M.H., V.L., C.L.G., M.B.), Université de Montréal, Montréal, QC, Canada; Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Miyagi, Japan (A.I., S.I., J.A.); Japan Science and Technology Agency, Precursory Research for Embryonic Science and Technology, Kawaguchi, Saitama, Japan (A.I.); and Japan Agency for Medical Research and Development, Core Research for Evolutional Science and Technology, Chiyoda-ku, Tokyo, Japan (J.A.)
| | - Asuka Inoue
- Department of Biochemistry (W.S., E.T.v.d.W., A.-M.S., B.P., M.B.) and Institute for Research in Immunology and Cancer (W.S., E.T.v.d.W., A.-M.S., B.P., M.H., V.L., C.L.G., M.B.), Université de Montréal, Montréal, QC, Canada; Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Miyagi, Japan (A.I., S.I., J.A.); Japan Science and Technology Agency, Precursory Research for Embryonic Science and Technology, Kawaguchi, Saitama, Japan (A.I.); and Japan Agency for Medical Research and Development, Core Research for Evolutional Science and Technology, Chiyoda-ku, Tokyo, Japan (J.A.)
| | - Satoru Ishida
- Department of Biochemistry (W.S., E.T.v.d.W., A.-M.S., B.P., M.B.) and Institute for Research in Immunology and Cancer (W.S., E.T.v.d.W., A.-M.S., B.P., M.H., V.L., C.L.G., M.B.), Université de Montréal, Montréal, QC, Canada; Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Miyagi, Japan (A.I., S.I., J.A.); Japan Science and Technology Agency, Precursory Research for Embryonic Science and Technology, Kawaguchi, Saitama, Japan (A.I.); and Japan Agency for Medical Research and Development, Core Research for Evolutional Science and Technology, Chiyoda-ku, Tokyo, Japan (J.A.)
| | - Junken Aoki
- Department of Biochemistry (W.S., E.T.v.d.W., A.-M.S., B.P., M.B.) and Institute for Research in Immunology and Cancer (W.S., E.T.v.d.W., A.-M.S., B.P., M.H., V.L., C.L.G., M.B.), Université de Montréal, Montréal, QC, Canada; Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Miyagi, Japan (A.I., S.I., J.A.); Japan Science and Technology Agency, Precursory Research for Embryonic Science and Technology, Kawaguchi, Saitama, Japan (A.I.); and Japan Agency for Medical Research and Development, Core Research for Evolutional Science and Technology, Chiyoda-ku, Tokyo, Japan (J.A.)
| | - Christian Le Gouill
- Department of Biochemistry (W.S., E.T.v.d.W., A.-M.S., B.P., M.B.) and Institute for Research in Immunology and Cancer (W.S., E.T.v.d.W., A.-M.S., B.P., M.H., V.L., C.L.G., M.B.), Université de Montréal, Montréal, QC, Canada; Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Miyagi, Japan (A.I., S.I., J.A.); Japan Science and Technology Agency, Precursory Research for Embryonic Science and Technology, Kawaguchi, Saitama, Japan (A.I.); and Japan Agency for Medical Research and Development, Core Research for Evolutional Science and Technology, Chiyoda-ku, Tokyo, Japan (J.A.)
| | - Michel Bouvier
- Department of Biochemistry (W.S., E.T.v.d.W., A.-M.S., B.P., M.B.) and Institute for Research in Immunology and Cancer (W.S., E.T.v.d.W., A.-M.S., B.P., M.H., V.L., C.L.G., M.B.), Université de Montréal, Montréal, QC, Canada; Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Miyagi, Japan (A.I., S.I., J.A.); Japan Science and Technology Agency, Precursory Research for Embryonic Science and Technology, Kawaguchi, Saitama, Japan (A.I.); and Japan Agency for Medical Research and Development, Core Research for Evolutional Science and Technology, Chiyoda-ku, Tokyo, Japan (J.A.)
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Cahill TJ, Thomsen ARB, Tarrasch JT, Plouffe B, Nguyen AH, Yang F, Huang LY, Kahsai AW, Bassoni DL, Gavino BJ, Lamerdin JE, Triest S, Shukla AK, Berger B, Little J, Antar A, Blanc A, Qu CX, Chen X, Kawakami K, Inoue A, Aoki J, Steyaert J, Sun JP, Bouvier M, Skiniotis G, Lefkowitz RJ. Distinct conformations of GPCR-β-arrestin complexes mediate desensitization, signaling, and endocytosis. Proc Natl Acad Sci U S A 2017; 114:2562-2567. [PMID: 28223524 PMCID: PMC5347553 DOI: 10.1073/pnas.1701529114] [Citation(s) in RCA: 241] [Impact Index Per Article: 34.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
β-Arrestins (βarrs) interact with G protein-coupled receptors (GPCRs) to desensitize G protein signaling, to initiate signaling on their own, and to mediate receptor endocytosis. Prior structural studies have revealed two unique conformations of GPCR-βarr complexes: the "tail" conformation, with βarr primarily coupled to the phosphorylated GPCR C-terminal tail, and the "core" conformation, where, in addition to the phosphorylated C-terminal tail, βarr is further engaged with the receptor transmembrane core. However, the relationship of these distinct conformations to the various functions of βarrs is unknown. Here, we created a mutant form of βarr lacking the "finger-loop" region, which is unable to form the core conformation but retains the ability to form the tail conformation. We find that the tail conformation preserves the ability to mediate receptor internalization and βarr signaling but not desensitization of G protein signaling. Thus, the two GPCR-βarr conformations can carry out distinct functions.
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Affiliation(s)
- Thomas J Cahill
- Department of Medicine, Duke University Medical Center, Durham, NC 27710
- Department of Biochemistry, Duke University Medical Center, Durham, NC 27710
| | - Alex R B Thomsen
- Department of Medicine, Duke University Medical Center, Durham, NC 27710
| | - Jeffrey T Tarrasch
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109
- Department of Pharmacology, University of Michigan, Ann Arbor, MI 48109
| | - Bianca Plouffe
- Department of Biochemistry, Institute for Research in Immunology and Cancer, University of Montreal, Montreal, QC H3C 3J7, Canada
| | - Anthony H Nguyen
- Department of Medicine, Duke University Medical Center, Durham, NC 27710
- Howard Hughes Medical Institute, Duke University Medical Center, Durham, NC 27710
| | - Fan Yang
- Department of Molecular Biology and Biochemistry, Shandong University School of Medicine, Jinan, Shandong 250012, China
| | - Li-Yin Huang
- Department of Medicine, Duke University Medical Center, Durham, NC 27710
| | - Alem W Kahsai
- Department of Medicine, Duke University Medical Center, Durham, NC 27710
| | | | | | | | - Sarah Triest
- Structural Biology Brussels, Vrije Universiteit Brussels, B-1050 Brussels, Belgium
- Structural Biology Research Center, Vlaams Instituut voor Biotechnologie, B-1050 Brussels, Belgium
| | - Arun K Shukla
- Department of Medicine, Duke University Medical Center, Durham, NC 27710
| | - Benjamin Berger
- Department of Biochemistry, Duke University Medical Center, Durham, NC 27710
| | - John Little
- Department of Biochemistry, Duke University Medical Center, Durham, NC 27710
| | - Albert Antar
- Department of Biochemistry, Duke University Medical Center, Durham, NC 27710
| | - Adi Blanc
- Department of Biochemistry, Duke University Medical Center, Durham, NC 27710
| | - Chang-Xiu Qu
- Department of Molecular Biology and Biochemistry, Shandong University School of Medicine, Jinan, Shandong 250012, China
| | - Xin Chen
- School of Pharmaceutical Engineering and Life Sciences, Changzhou University, Changzhou, Jiangsu 213164, China
| | - Kouki Kawakami
- Graduate School of Pharmaceutical Science, Tohoku University, Sendai, Miyagi 980-8578, Japan
| | - Asuka Inoue
- Graduate School of Pharmaceutical Science, Tohoku University, Sendai, Miyagi 980-8578, Japan
- Japan Science and Technology Agency (JST), Precursory Research for Embryonic Science and Technology (PRESTO), Kawaguchi, Saitama 332-0012, Japan
| | - Junken Aoki
- Graduate School of Pharmaceutical Science, Tohoku University, Sendai, Miyagi 980-8578, Japan
- Core Research for Evolutionary Science and Technology (AMED-CREST), Japan Agency for Medical Research and Development, Chiyoda-ku, Tokyo 100-0004, Japan
| | - Jan Steyaert
- Structural Biology Brussels, Vrije Universiteit Brussels, B-1050 Brussels, Belgium
- Structural Biology Research Center, Vlaams Instituut voor Biotechnologie, B-1050 Brussels, Belgium
| | - Jin-Peng Sun
- Department of Molecular Biology and Biochemistry, Shandong University School of Medicine, Jinan, Shandong 250012, China
| | - Michel Bouvier
- Department of Biochemistry, Institute for Research in Immunology and Cancer, University of Montreal, Montreal, QC H3C 3J7, Canada
| | - Georgios Skiniotis
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109
- Department of Pharmacology, University of Michigan, Ann Arbor, MI 48109
| | - Robert J Lefkowitz
- Department of Medicine, Duke University Medical Center, Durham, NC 27710;
- Department of Biochemistry, Duke University Medical Center, Durham, NC 27710
- Howard Hughes Medical Institute, Duke University Medical Center, Durham, NC 27710
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19
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Thomsen ARB, Plouffe B, Cahill TJ, Shukla AK, Tarrasch JT, Dosey AM, Kahsai AW, Strachan RT, Pani B, Mahoney JP, Huang L, Breton B, Heydenreich FM, Sunahara RK, Skiniotis G, Bouvier M, Lefkowitz RJ. GPCR-G Protein-β-Arrestin Super-Complex Mediates Sustained G Protein Signaling. Cell 2016; 166:907-919. [PMID: 27499021 PMCID: PMC5418658 DOI: 10.1016/j.cell.2016.07.004] [Citation(s) in RCA: 367] [Impact Index Per Article: 45.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2016] [Revised: 05/13/2016] [Accepted: 07/07/2016] [Indexed: 01/14/2023]
Abstract
Classically, G protein-coupled receptor (GPCR) stimulation promotes G protein signaling at the plasma membrane, followed by rapid β-arrestin-mediated desensitization and receptor internalization into endosomes. However, it has been demonstrated that some GPCRs activate G proteins from within internalized cellular compartments, resulting in sustained signaling. We have used a variety of biochemical, biophysical, and cell-based methods to demonstrate the existence, functionality, and architecture of internalized receptor complexes composed of a single GPCR, β-arrestin, and G protein. These super-complexes or "megaplexes" more readily form at receptors that interact strongly with β-arrestins via a C-terminal tail containing clusters of serine/threonine phosphorylation sites. Single-particle electron microscopy analysis of negative-stained purified megaplexes reveals that a single receptor simultaneously binds through its core region with G protein and through its phosphorylated C-terminal tail with β-arrestin. The formation of such megaplexes provides a potential physical basis for the newly appreciated sustained G protein signaling from internalized GPCRs.
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Affiliation(s)
- Alex R B Thomsen
- Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA
| | - Bianca Plouffe
- Department of Biochemistry and Institute for Research in Immunology and Cancer, University of Montreal, Montreal, QC H3C 3J7, Canada
| | - Thomas J Cahill
- Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA; Department of Biochemistry, Duke University Medical Center, Durham, NC 27710, USA
| | - Arun K Shukla
- Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA
| | - Jeffrey T Tarrasch
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109, USA
| | - Annie M Dosey
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109, USA
| | - Alem W Kahsai
- Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA
| | - Ryan T Strachan
- Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA
| | - Biswaranjan Pani
- Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA
| | - Jacob P Mahoney
- Department of Pharmacology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Liyin Huang
- Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA
| | - Billy Breton
- Department of Biochemistry and Institute for Research in Immunology and Cancer, University of Montreal, Montreal, QC H3C 3J7, Canada
| | - Franziska M Heydenreich
- Department of Biochemistry and Institute for Research in Immunology and Cancer, University of Montreal, Montreal, QC H3C 3J7, Canada
| | - Roger K Sunahara
- Department of Pharmacology, University of Michigan, Ann Arbor, MI 48109, USA; Department of Pharmacology, University of California, San Diego, La Jolla, CA 92093, USA
| | - Georgios Skiniotis
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109, USA
| | - Michel Bouvier
- Department of Biochemistry and Institute for Research in Immunology and Cancer, University of Montreal, Montreal, QC H3C 3J7, Canada.
| | - Robert J Lefkowitz
- Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA; Department of Biochemistry, Duke University Medical Center, Durham, NC 27710, USA; Howard Hughes Medical Institute, Duke University Medical Center, Durham, NC 27710, USA.
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20
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Calvier L, Legchenko E, Grimm L, Sallmon H, Hatch A, Plouffe B, Schroeder C, Bauersachs J, Murthy S, Hansmann G. Galectin-3 and Aldosterone as Potential Tandem Biomarkers in Pulmonary Arterial Hypertension. Thorac Cardiovasc Surg 2016. [DOI: 10.1055/s-0036-1571946] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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21
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Abstract
The concept of activation in the absence of agonists has been demonstrated for many GPCRs and is now solidified as one of the principal aspects of GPCR signaling. In this chapter, we review how dopamine receptors demonstrate this ability. Although difficult to prove in vivo due to the presence of endogenous dopamine and lack of subtype-selective inverse agonists and "pure" antagonists (neutral ligands), in vitro assays such as measuring intracellular cAMP, [(35)S]GTPγS binding, and [(3)H]thymidine incorporation have uncovered the constitutive activation of D1- and D2-class receptors. Nevertheless, because of limited and inconsistent findings, the existence of constitutive activity for D2-class receptors is currently not well established. Mutagenesis studies have shown that basal signaling, notably by D1-class receptors, is governed by the collective contributions of transmembrane domains and extracellular/intracellular loops, such as the third extracellular loop, the third intracellular loop, and C-terminal tail. Furthermore, constitutive activities of D1-class receptors are subjected to regulation by kinases. Among the dopamine receptor family, the D5 receptor subtype exhibits a higher basal signaling and bears resemblance to constitutively active mutant forms of GPCRs. The presence of its constitutive activity in vivo and its pathophysiological relevance, with a brief mention of other subtypes, are also discussed.
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Affiliation(s)
- Boyang Zhang
- Ottawa Hospital Research Institute (Neuroscience Program), Ottawa, Ontario, Canada; Departments of Medicine, Cellular & Molecular Medicine, Psychiatry, University of Ottawa, Ottawa, Ontario, Canada
| | - Awatif Albaker
- Ottawa Hospital Research Institute (Neuroscience Program), Ottawa, Ontario, Canada; Departments of Medicine, Cellular & Molecular Medicine, Psychiatry, University of Ottawa, Ottawa, Ontario, Canada
| | - Bianca Plouffe
- Department of Biochemistry, Université de Montréal, Montréal, Québec, Canada; Institut de recherche en immunologie, cancer, Montréal, Québec, Canada
| | - Caroline Lefebvre
- Ottawa Hospital Research Institute (Neuroscience Program), Ottawa, Ontario, Canada; Departments of Medicine, Cellular & Molecular Medicine, Psychiatry, University of Ottawa, Ottawa, Ontario, Canada
| | - Mario Tiberi
- Ottawa Hospital Research Institute (Neuroscience Program), Ottawa, Ontario, Canada; Departments of Medicine, Cellular & Molecular Medicine, Psychiatry, University of Ottawa, Ottawa, Ontario, Canada.
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22
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Plouffe B, Yang X, Tiberi M. The third intracellular loop of D1 and D5 dopaminergic receptors dictates their subtype-specific PKC-induced sensitization and desensitization in a receptor conformation-dependent manner. Cell Signal 2011; 24:106-18. [PMID: 21893192 DOI: 10.1016/j.cellsig.2011.08.008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2011] [Revised: 08/05/2011] [Accepted: 08/17/2011] [Indexed: 01/11/2023]
Abstract
We previously showed that phorbol-12-myristate-13-acetate (PMA) mediates a robust PKC-dependent sensitization and desensitization of the highly homologous human Gs protein and adenylyl cyclase (AC)-linked D1 (hD1R) and D5 (hD5R) dopaminergic receptors, respectively. Here, we demonstrate using forskolin-mediated AC stimulation that PMA-mediated hD1R sensitization and hD5R desensitization is not associated with changes in AC activity. We next employed a series of chimeric hD1R and hD5R to delineate the underlying structural determinants dictating the subtype-specific regulation of human D1-like receptors by PMA. We first used chimeric receptors in which the whole terminal region (TR) spanning from the extracellular face of transmembrane domain 6 to the end of cytoplasmic tail (CT) or CT alone were exchanged between hD1R and hD5R. CT and TR swaps lead to chimeric hD1R and hD5R retaining PMA-induced sensitization and desensitization of wild type parent receptors. In striking contrast, hD1R sensitization and hD5R desensitization mediated by PMA are correspondingly switched to PMA-induced receptor desensitization and sensitization following the IL3 swap between hD1R and hD5R. Cell treatment with the PKC blocker, Gö6983, inhibits PMA-induced regulation of these chimeric receptors in a similar fashion to wild type receptors. Further studies with chimeras constructed by exchanging IL3 and TR show that PMA-induced regulation of these chimeras remains fully switched relative to their respective wild type parent receptor. Interestingly, results obtained with the exchange of IL3 and TR also reveal that the D1-like subtype-specific regulation by PMA, while fully dictated by IL3, can be modulated in a receptor conformation-dependent manner. Overall, our results strongly suggest that IL3 is the critical determinant underlying the subtype-specific regulation of human D1-like receptor responsiveness by PKC.
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Affiliation(s)
- Bianca Plouffe
- Ottawa Hospital Research Institute, Department of Medicine, University of Ottawa, Ottawa, ON, Canada
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23
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Abstract
Dopamine D1 and D5 receptors are prototypical cell-surface seven-transmembrane (TM) G protein-coupled receptors (GPCRs) mediating elevation of intracellular cAMP levels. The high level of constitutive activity of D5 receptor mediating intracellular cAMP production is one of the functional hallmarks distinguishing the closely related D1-like dopaminergic subtypes (D1 and D5). D1-like subtypes share over 80% identity within their TM regions. Thus, D1 and D5 receptors can serve as unparalleled and useful molecular tools to gain structural and mechanistic insights into subtype-specific determinants regulating GPCR constitutive activation and inverse agonism. A method has been developed that relies on the use of transfected human embryonic kidney 293 cells with wild-type (WT), epitope-tagged, chimeric, truncated, and mutant forms of mammalian D1 and D5 receptors using a modified DNA and calcium phosphate precipitation procedure. Receptor expression levels are quantified by a radioligand binding using [(3)H]-SCH23390, a D1-like selective drug. Regulation of ligand-independent and dependent activity of WT and mutated D1 and D5 receptors is determined by whole cell cAMP assays using metabolic [(3)H]-adenine labeling and sequential purification radiolabeled nucleotides over Dowex and alumina resin columns. Results on the regulation of D1 and D5 constitutive activity are presented here. Our studies indicate that dopamine-mediated D5 receptor stimulation in a dose-dependent manner is not always detectable, suggesting that D5 receptors can exist in a "locked" constitutively activated state. This "locked" constitutively active state of D5 receptor is not linked to aberrant high receptor expression levels or cell behavior, as D1 receptor function remains essentially unchanged in these cells. In fact, we show that phorbol ester treatment of cells harboring "locked" constitutively active D5 receptors abrogates constitutive activation of D5R to allow its stimulation by dopamine in a dose-dependent manner.
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Affiliation(s)
- Bianca Plouffe
- Ottawa Hospital Research Institute (Neurosciences), Department of Medicine, University of Ottawa, Ontario, Canada
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24
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Plouffe B, Tiberi M. Opposite Regulation of Human D1‐like Dopaminergic Responsiveness by Protein Kinase C is Shaped by Two Critical Serine Residues of the Third Intracellular Loop of Human D5 Dopaminergic Receptor. FASEB J 2008; 22. [DOI: 10.1096/fasebj.22.1_supplement.1050.3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/02/2023]
Affiliation(s)
- Bianca Plouffe
- Medicine/Cellular and Molecular Medicine/PsychiatryUniversity of OttawaOttawaCanada
- Ottawa Health Research InstituteOttawaCanada
| | - Mario Tiberi
- Medicine/Cellular and Molecular Medicine/PsychiatryUniversity of OttawaOttawaCanada
- Ottawa Health Research InstituteOttawaCanada
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25
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Yang X, Sedaghat K, Plouffe B, Gorji H, Tiberi M. Phosphorylation and hetero‐oligomerization regulate the dopamine D3 receptor/adenylyl cyclase type 5 signaling complex. FASEB J 2008. [DOI: 10.1096/fasebj.22.1_supplement.831.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Xiaodi Yang
- Medicine/Cellular and Molecular Medicine/PsychiatryUniversity of OttawaOttawaCanada
- Ottawa Health Research InstituteOttawaCanada
| | - Keyvan Sedaghat
- Medicine/Cellular and Molecular Medicine/PsychiatryUniversity of OttawaOttawaCanada
- Ottawa Health Research InstituteOttawaCanada
| | - Bianca Plouffe
- Medicine/Cellular and Molecular Medicine/PsychiatryUniversity of OttawaOttawaCanada
- Ottawa Health Research InstituteOttawaCanada
| | - Hassan Gorji
- Medicine/Cellular and Molecular Medicine/PsychiatryUniversity of OttawaOttawaCanada
- Ottawa Health Research InstituteOttawaCanada
| | - Mario Tiberi
- Medicine/Cellular and Molecular Medicine/PsychiatryUniversity of OttawaOttawaCanada
- Ottawa Health Research InstituteOttawaCanada
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26
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Murugaiah AMS, Wallinder C, Mahalingam AK, Wu X, Wan Y, Plouffe B, Botros M, Karlén A, Hallberg M, Gallo-Payet N, Alterman M. Selective angiotensin II AT2 receptor agonists devoid of the imidazole ring system. Bioorg Med Chem 2007; 15:7166-83. [PMID: 17825570 DOI: 10.1016/j.bmc.2007.07.026] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2007] [Revised: 06/28/2007] [Accepted: 07/06/2007] [Indexed: 11/19/2022]
Abstract
A versatile parallel synthetic method to obtain three series of non-cyclic analogues of the first drug-like selective angiotensin II AT(2) receptor agonist (1) has been developed. In analogy with the transformation of losartan to valsartan it was demonstrated that a non-cyclic moiety could be employed as an imidazole replacement to obtain AT(2) selective compounds. In all the three series, AT(2) receptor ligands with affinities in the lower nanomolar range were found. None of the analogues exhibited any affinity for the AT(1) receptor. Four compounds, 17, 22, 39 and 51, were examined in a neurite outgrowth cell assay. All four compounds were found to exert a high agonistic effect as deduced from their capacity to induce neurite elongation in neuronal cells, as does angiotensin II.
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Affiliation(s)
- A M S Murugaiah
- Department of Medicinal Chemistry, BMC, Uppsala University, PO Box 574, SE-751 23 Uppsala, Sweden
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27
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Wu X, Wan Y, Mahalingam AK, Murugaiah AMS, Plouffe B, Botros M, Karlén A, Hallberg M, Gallo-Payet N, Alterman M. Selective Angiotensin II AT2 Receptor Agonists: Arylbenzylimidazole Structure−Activity Relationships. J Med Chem 2006; 49:7160-8. [PMID: 17125268 DOI: 10.1021/jm0606185] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Structural alterations in the 2- and 5-positions of the first drug-like selective angiotensin II AT2 receptor agonist (1) have been performed. The imidazole ring system was proven to be a strong determinant for the AT2 selectivity, and with few exceptions all variations gave good AT2 receptor affinities and with retained high AT2/AT1 selectivities. On the contrary to the findings with AT1 receptor agonists, the impact of structural modifications in the 5-position of the AT2 selective compounds were less pronounced regarding activation of the AT2 receptor. The butyloxyphenyl (56) and the propylthienyl (50) derivatives were found to exert a high agonistic effect as deduced from their capacity to induce neurite elongation in neuronal cells, as does angiotensin II.
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Affiliation(s)
- Xiongyu Wu
- Department of Medicinal Chemistry, BMC, Uppsala University, P.O. Box 574, SE-751 23 Uppsala, Sweden
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28
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Plouffe B, Guimond MO, Beaudry H, Gallo-Payet N. Role of tyrosine kinase receptors in angiotensin II AT2 receptor signaling: involvement in neurite outgrowth and in p42/p44mapk activation in NG108-15 cells. Endocrinology 2006; 147:4646-54. [PMID: 16809450 DOI: 10.1210/en.2005-1315] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
NG108-15 cells, which have a rounding-up morphology when cultured in serum-supplemented medium, extend neurites when stimulated for 3 d with angiotensin II (Ang II). The aim of the present study was to investigate whether growth factor receptors are necessary for mediating the effects of Ang II. A 3-d treatment with AG879, an inhibitor of nerve growth factor receptor TrkA, strongly affected neurite outgrowth and phosphorylation of p42/p44(mapk) induced by Ang II. PD168393, an inhibitor of epidermal growth factor (EGF) receptor slightly decreased Ang II-induced neurite outgrowth, whereas AG213, an inhibitor of both platelet-derived growth factor receptor and EGF receptor, stimulated neurite outgrowth and p42/p44(mapk) phosphorylation on its own, without affecting further stimulation with Ang II. Moreover, Ang II induced the phosphorylation of TrkA (maximum at 5 min of incubation in the presence of serum or at 20 min in cells depleted in serum for 2 h) and a rapid increase in Rap1 activity, both effects abolished in cells preincubated with 10 microm AG879. In summary, the present results demonstrate that AT(2) receptor-induced sustained activation of p42/p44(mapk) and corresponding neurite outgrowth are mediated by phosphorylation of the nerve growth factor TrkA receptor. However, the results also point out that the presence of other growth factors, such as EGF or PDFG, may interfere with the effect of Ang II. Altogether, the current findings clearly indicate that the effects of the AT(2) receptor on neurite outgrowth dynamics are modulated by the presence of growth factors in the culture medium.
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Affiliation(s)
- Bianca Plouffe
- Service of Endocrinology, and Department of Physiology and Biophysics, Faculty of Medicine, University of Sherbrooke, Sherbrooke, Quebec, Canada J1H 5N4
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29
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Georgsson J, Rosenström U, Wallinder C, Beaudry H, Plouffe B, Lindeberg G, Botros M, Nyberg F, Karlén A, Gallo-Payet N, Hallberg A. Short pseudopeptides containing turn scaffolds with high AT2 receptor affinity. Bioorg Med Chem 2006; 14:5963-72. [PMID: 16753301 DOI: 10.1016/j.bmc.2006.05.019] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2005] [Revised: 05/04/2006] [Accepted: 05/15/2006] [Indexed: 11/22/2022]
Abstract
Two pentapeptides, Ac-Tyr-Ile-His-Pro-Phe/Ile, were synthesized and shown to have angiotensin II AT2 receptor affinity and agonistic activity. Based on these peptides, a new series of 13 pseudopeptides was synthesized via introduction of five different turn scaffolds replacing the Tyr-Ile amino acid residues. Pharmacological evaluation disclosed subnanomolar affinities for some of these compounds at the AT2 receptor. Substitution of Phe by Ile in this series of ligands enhanced the AT2 receptor affinity of all compounds. These results suggest that the C-terminal amino acid residues can be elaborated on to enhance the AT2 receptor affinity in truncated Ang II analogues.
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Affiliation(s)
- Jennie Georgsson
- Department of Medicinal Chemistry, Division of Organic Pharmaceutical Chemistry, Uppsala University, PO Box 574, SE-751 23 Uppsala, Sweden
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30
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Georgsson J, Sköld C, Plouffe B, Lindeberg G, Botros M, Larhed M, Nyberg F, Gallo-Payet N, Gogoll A, Karlén A, Hallberg A. Angiotensin II pseudopeptides containing 1,3,5-trisubstituted benzene scaffolds with high AT2 receptor affinity. J Med Chem 2005; 48:6620-31. [PMID: 16220978 DOI: 10.1021/jm050280z] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Two 1,3,5-trisubstituted aromatic scaffolds intended to serve as gamma-turn mimetics have been synthesized and incorporated in five pseudopeptide analogues of angiotensin II (Asp-Arg-Val-Tyr-Ile-His-Pro-Phe), replacing Val-Tyr-Ile, Val-Tyr, or Tyr-Ile. All the tested compounds exhibited nanomolar affinity for the AT2 receptor with the best compound (3) having a K(i) of 1.85 nM. Four pseudopeptides were AT2 selective, while one (5) also exhibited good affinity for the AT1 receptor (K(i) = 30.3 nM). This pseudopeptide exerted full agonistic activity in an AT2 receptor induced neurite outgrowth assay but displayed no agonistic effect in an AT1 receptor functional assay. Molecular modeling, using the program DISCOtech, showed that the high-affinity ligands could interact similarly with the AT2 receptor as other ligands with high affinity for this receptor. A tentative agonist model is proposed for AT2 receptor activation by angiotensin II analogues. We conclude that the 1,3,5-trisubstituted benzene rings can be conveniently prepared and are suitable as gamma-turn mimics.
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MESH Headings
- Angiotensin II/analogs & derivatives
- Angiotensin II/chemical synthesis
- Angiotensin II/pharmacology
- Animals
- Aorta, Thoracic/drug effects
- Aorta, Thoracic/physiology
- Benzene Derivatives/chemical synthesis
- Benzene Derivatives/pharmacology
- Cell Line, Tumor
- Female
- In Vitro Techniques
- Ligands
- Liver/metabolism
- Models, Molecular
- Molecular Mimicry
- Muscle Contraction/drug effects
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/physiology
- Myometrium/metabolism
- Neurites/drug effects
- Neurites/physiology
- Oligopeptides/chemical synthesis
- Oligopeptides/pharmacology
- Protein Structure, Secondary
- Rabbits
- Radioligand Assay
- Rats
- Receptor, Angiotensin, Type 1/agonists
- Receptor, Angiotensin, Type 1/metabolism
- Receptor, Angiotensin, Type 2/agonists
- Receptor, Angiotensin, Type 2/metabolism
- Swine
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Affiliation(s)
- Jennie Georgsson
- Department of Medicinal Chemistry, Division of Organic Pharmaceutical Chemistry, Uppsala University, P.O. Box 574, SE-751 23 Uppsala, Sweden
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31
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Rosenström U, Sköld C, Plouffe B, Beaudry H, Lindeberg G, Botros M, Nyberg F, Wolf G, Karlén A, Gallo-Payet N, Hallberg A. New selective AT2 receptor ligands encompassing a gamma-turn mimetic replacing the amino acid residues 4-5 of angiotensin II act as agonists. J Med Chem 2005; 48:4009-24. [PMID: 15943474 DOI: 10.1021/jm0491492] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
New benzodiazepine-based gamma-turn mimetics with one or two amino acid side chains were synthesized. The gamma-turn mimetics were incorporated into angiotensin II (Ang II) replacing the Val(3)-Tyr(4)-Ile(5) or Tyr(4)-Ile(5) peptide segments. All of the resulting pseudopeptides displayed high AT(2)/AT(1) receptor selectivity and exhibited AT(2) receptor affinity in the low nanomolar range. Molecular modeling was used to investigate whether the compounds binding to the AT(2) receptor could position important structural elements in common areas. A previously described benzodiazepine-based gamma-turn mimetic with high affinity for the AT(2) receptor was also included in the modeling. It was found that the molecules, although being structurally quite different, could adopt the same binding mode/interaction pattern in agreement with the model hypothesis. The pseudopeptides selected for agonist studies were shown to act as AT(2) receptor agonists being able to induce outgrowth of neurite cells, stimulate p42/p44(mapk), and suppress proliferation of PC12 cells.
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32
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Wan Y, Wallinder C, Plouffe B, Beaudry H, Mahalingam AK, Wu X, Johansson B, Holm M, Botoros M, Karlén A, Pettersson A, Nyberg F, Fändriks L, Gallo-Payet N, Hallberg A, Alterman M. Design, synthesis, and biological evaluation of the first selective nonpeptide AT2 receptor agonist. J Med Chem 2005; 47:5995-6008. [PMID: 15537354 DOI: 10.1021/jm049715t] [Citation(s) in RCA: 268] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The first druglike selective angiotensin II AT(2) receptor agonist (21) with a K(i) value of 0.4 nM for the AT(2) receptor and a K(i) > 10 microM for the AT(1) receptor is reported. Compound 21, with a bioavailability of 20-30% after oral administration and a half-life estimated to 4 h in rat, induces outgrowth of neurite cells, stimulates p42/p44(mapk), enhances in vivo duodenal alkaline secretion in Sprague-Dawley rats, and lowers the mean arterial blood pressure in anesthetized, spontaneously hypertensive rats. Thus, the peptidomimetic 21 exerts a similar biological response as the endogenous peptide angiotensin II after selective activation of the AT(2) receptor. Compound 21, derived from the prototype nonselective AT(1)/AT(2) receptor agonist L-162,313 will serve as a valuable research tool, enabling studies of the function of the AT(2) receptor in more detail.
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Affiliation(s)
- Yiqian Wan
- Department of Medicinal Chemistry, BMC, Uppsala University, P.O. Box 574, SE-751 23 Uppsala, Sweden
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33
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Després N, Talbot G, Plouffe B, Boire G, Ménard HA. Detection and expression of a cDNA clone that encodes a polypeptide containing two inhibitory domains of human calpastatin and its recognition by rheumatoid arthritis sera. J Clin Invest 1995; 95:1891-6. [PMID: 7706496 PMCID: PMC295733 DOI: 10.1172/jci117870] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
RA is the most frequent and most destructive inflammatory arthropathy. Rheumatoid factors, in spite of their lack of disease specificity, are important serological markers for RA and appear important in its immunopathogenesis as well. In search of more disease-specific autoimmune systems, we have screened a human placenta lambda gt11 cDNA expression library using selected sera from patients with classical erosive RA. We have identified one clone (RA-1) that is recognized by three of five screening sera. The 950-bp insert shows a complete nucleotide sequence homology to the cDNA encoding the two COOH-terminal domains of calpastatin. The deduced open reading frame of the RA-1 cDNA predicts a 284-amino acid protein, with a calculated mol wt of 35.9 kD. Calpastatin is the natural inhibitor of calpains, which are members of the cysteine proteinases recently implicated in joint destruction in rheumatic diseases. The two domains encoded by the RA-1 clone each contain the structural features associated with the inhibitory activity of human calpastatin. By Western blotting, 45.5% or 21/44 RA sera specifically recognized both the fusion and the cleaved recombinant protein. This is in contrast to 4.7% (2/43) in nonrheumatoid sera and 0/10 in normal sera. Anticalpastatin autoantibodies could represent a disease-associated marker in chronic erosive arthritis of the rheumatoid type and could hypothetically play a dual pathogenic role, directly via an immune interference and indirectly through an immune complex mechanism.
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Affiliation(s)
- N Després
- Rheumatic Diseases Unit, Faculty of Medicine, Université de Sherbrooke, Québec, Canada
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