1
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Mach L, Omran A, Bouma J, Radetzki S, Sykes DA, Guba W, Li X, Höffelmeyer C, Hentsch A, Gazzi T, Mostinski Y, Wasinska-Kalwa M, de Molnier F, van der Horst C, von Kries JP, Vendrell M, Hua T, Veprintsev DB, Heitman LH, Grether U, Nazare M. Highly Selective Drug-Derived Fluorescent Probes for the Cannabinoid Receptor Type 1 (CB 1R). J Med Chem 2024; 67:11841-11867. [PMID: 38990855 DOI: 10.1021/acs.jmedchem.4c00465] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/13/2024]
Abstract
The cannabinoid receptor type 1 (CB1R) is pivotal within the endocannabinoid system regulating various signaling cascades with effects in appetite regulation, pain perception, memory formation, and thermoregulation. Still, understanding of CB1R's cellular signaling, distribution, and expression dynamics is very fragmentary. Real-time visualization of CB1R is crucial for addressing these questions. Selective drug-like CB1R ligands with a defined pharmacological profile were investigated for the construction of CB1R fluorescent probes using a reverse design-approach. A modular design concept with a diethyl glycine-based building block as the centerpiece allowed for the straightforward synthesis of novel probe candidates. Validated by computational docking studies, radioligand binding, and cAMP assay, this systematic approach allowed for the identification of novel pyrrole-based CB1R fluorescent probes. Application in fluorescence-based target-engagement studies and live cell imaging exemplify the great versatility of the tailored CB1R probes for investigating CB1R localization, trafficking, pharmacology, and its pathological implications.
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Affiliation(s)
- Leonard Mach
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), 13125 Berlin, Germany
| | - Anahid Omran
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), 13125 Berlin, Germany
| | - Jara Bouma
- Division of Drug Discovery and Safety, Leiden Academic Centre for Drug Research, Leiden University and Oncode Institute, 2333 CC Leiden, The Netherlands
| | - Silke Radetzki
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), 13125 Berlin, Germany
| | - David A Sykes
- Division of Physiology, Pharmacology & Neuroscience, School of Life Sciences, University of Nottingham, NG7 2UH Nottingham, U.K
- Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham and University of Nottingham, Edgbaston, B15 2TT Birmingham, Midlands, U.K
| | - Wolfgang Guba
- Roche Pharma Research & Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd., 4070 Basel, Switzerland
| | - Xiaoting Li
- iHuman Institute, ShanghaiTech University, 201210 Shanghai, China
- School of Life Science and Technology, ShanghaiTech University, 201210 Shanghai, China
| | - Calvin Höffelmeyer
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), 13125 Berlin, Germany
| | - Axel Hentsch
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), 13125 Berlin, Germany
| | - Thais Gazzi
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), 13125 Berlin, Germany
| | - Yelena Mostinski
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), 13125 Berlin, Germany
| | | | - Fabio de Molnier
- IRR Chemistry Hub and Centre for Inflammation Research, Institute for Regeneration and Repair, University of Edinburgh, EH16 4UU Edinburgh, U.K
| | - Cas van der Horst
- Division of Drug Discovery and Safety, Leiden Academic Centre for Drug Research, Leiden University and Oncode Institute, 2333 CC Leiden, The Netherlands
| | - Jens Peter von Kries
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), 13125 Berlin, Germany
| | - Marc Vendrell
- IRR Chemistry Hub and Centre for Inflammation Research, Institute for Regeneration and Repair, University of Edinburgh, EH16 4UU Edinburgh, U.K
| | - Tian Hua
- iHuman Institute, ShanghaiTech University, 201210 Shanghai, China
- School of Life Science and Technology, ShanghaiTech University, 201210 Shanghai, China
| | - Dmitry B Veprintsev
- Division of Physiology, Pharmacology & Neuroscience, School of Life Sciences, University of Nottingham, NG7 2UH Nottingham, U.K
- Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham and University of Nottingham, Edgbaston, B15 2TT Birmingham, Midlands, U.K
| | - Laura H Heitman
- Division of Drug Discovery and Safety, Leiden Academic Centre for Drug Research, Leiden University and Oncode Institute, 2333 CC Leiden, The Netherlands
| | - Uwe Grether
- Roche Pharma Research & Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd., 4070 Basel, Switzerland
| | - Marc Nazare
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), 13125 Berlin, Germany
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2
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Andersen C, Zulueta Díaz YDLM, Kure JL, Hessellund Eriksen M, Lovatt AL, Lagerholm C, Morales S, Sehayek S, Sheard TMD, Wiseman PW, Arnspang EC. Angiotensin II Treatment Induces Reorganization and Changes in the Lateral Dynamics of Angiotensin II Type 1 Receptor in the Plasma Membrane Elucidated by Photoactivated Localization Microscopy Combined with Image Spatial Correlation Analysis. Anal Chem 2023; 95:730-738. [PMID: 36574961 DOI: 10.1021/acs.analchem.2c02720] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The mechanisms by which angiotensin II type 1 receptor is distributed and the diffusional pattern in the plasma membrane (PM) remain unclear, despite their crucial role in cardiovascular homeostasis. In this work, we obtained quantitative information of angiotensin II type 1 receptor (AT1R) lateral dynamics as well as changes in the diffusion properties after stimulation with ligands in living cells using photoactivated localization microscopy (PALM) combined with image spatial-temporal correlation analysis. To study the organization of the receptor at the nanoscale, expansion microscopy (ExM) combined with PALM was performed. This study revealed that AT1R lateral diffusion increased after binding to angiotensin II (Ang II) and the receptor diffusion was transiently confined in the PM. In addition, ExM revealed that AT1R formed nanoclusters at the PM and the cluster size significantly decreased after Ang II treatment. Taking these results together suggest that Ang II binding and activation cause reorganization and changes in the dynamics of AT1R at the PM.
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Affiliation(s)
- Camilla Andersen
- SDU Biotechnology, Department of Green Technology, University of Southern Denmark, Odense M5230, Denmark
| | | | - Jakob L Kure
- SDU Biotechnology, Department of Green Technology, University of Southern Denmark, Odense M5230, Denmark
| | - Mathias Hessellund Eriksen
- SDU Biotechnology, Department of Green Technology, University of Southern Denmark, Odense M5230, Denmark
| | - Adam Leslie Lovatt
- SDU Biotechnology, Department of Green Technology, University of Southern Denmark, Odense M5230, Denmark
| | | | - Sebastian Morales
- Department of Physics and Department of Chemistry, McGill University, MontrealH3A 0B8, Canada
| | - Simon Sehayek
- Department of Physics and Department of Chemistry, McGill University, MontrealH3A 0B8, Canada
| | - Thomas M D Sheard
- School of Biosciences, University of Sheffield, SheffieldS10 2TN, U.K
| | - Paul W Wiseman
- Department of Physics and Department of Chemistry, McGill University, MontrealH3A 0B8, Canada
| | - Eva C Arnspang
- SDU Biotechnology, Department of Green Technology, University of Southern Denmark, Odense M5230, Denmark
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3
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Kok ZY, Stoddart LA, Mistry SJ, Mocking TAM, Vischer HF, Leurs R, Hill SJ, Mistry SN, Kellam B. Optimization of Peptide Linker-Based Fluorescent Ligands for the Histamine H 1 Receptor. J Med Chem 2022; 65:8258-8288. [PMID: 35734860 PMCID: PMC9234962 DOI: 10.1021/acs.jmedchem.2c00125] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The histamine H1 receptor (H1R) has recently been implicated in mediating cell proliferation and cancer progression; therefore, high-affinity H1R-selective fluorescent ligands are desirable tools for further investigation of this behavior in vitro and in vivo. We previously reported a H1R fluorescent ligand, bearing a peptide-linker, based on antagonist VUF13816 and sought to further explore structure-activity relationships (SARs) around the linker, orthostere, and fluorescent moieties. Here, we report a series of high-affinity H1R fluorescent ligands varying in peptide linker composition, orthosteric targeting moiety, and fluorophore. Incorporation of a boron-dipyrromethene (BODIPY) 630/650-based fluorophore conferred high binding affinity to our H1R fluorescent ligands, remarkably overriding the linker SAR observed in corresponding unlabeled congeners. Compound 31a, both potent and subtype-selective, enabled H1R visualization using confocal microscopy at a concentration of 10 nM. Molecular docking of 31a with the human H1R predicts that the optimized peptide linker makes interactions with key residues in the receptor.
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Affiliation(s)
- Zhi Yuan Kok
- Division of Biomolecular Science and Medicinal Chemistry, School of Pharmacy, University of Nottingham Biodiscovery Institute, University Park, Nottingham NG7 2RD, U.K.,Centre of Membrane Proteins and Receptors, University of Birmingham and University of Nottingham, the Midlands, Nottingham NG7 2UH, U.K
| | - Leigh A Stoddart
- Division of Physiology, Pharmacology & Neuroscience, Medical School, School of Life Sciences, University of Nottingham, Nottingham NG7 2UH, U.K.,Centre of Membrane Proteins and Receptors, University of Birmingham and University of Nottingham, the Midlands, Nottingham NG7 2UH, U.K
| | - Sarah J Mistry
- Division of Biomolecular Science and Medicinal Chemistry, School of Pharmacy, University of Nottingham Biodiscovery Institute, University Park, Nottingham NG7 2RD, U.K.,Centre of Membrane Proteins and Receptors, University of Birmingham and University of Nottingham, the Midlands, Nottingham NG7 2UH, U.K
| | - Tamara A M Mocking
- Amsterdam Institute for Molecules, Medicines and Systems, Division of Medicinal Chemistry, Faculty of Science, Vrije Universiteit Amsterdam, De Boelelean 1083, 1083 HV Amsterdam, The Netherlands
| | - Henry F Vischer
- Amsterdam Institute for Molecules, Medicines and Systems, Division of Medicinal Chemistry, Faculty of Science, Vrije Universiteit Amsterdam, De Boelelean 1083, 1083 HV Amsterdam, The Netherlands
| | - Rob Leurs
- Amsterdam Institute for Molecules, Medicines and Systems, Division of Medicinal Chemistry, Faculty of Science, Vrije Universiteit Amsterdam, De Boelelean 1083, 1083 HV Amsterdam, The Netherlands
| | - Stephen J Hill
- Division of Physiology, Pharmacology & Neuroscience, Medical School, School of Life Sciences, University of Nottingham, Nottingham NG7 2UH, U.K.,Centre of Membrane Proteins and Receptors, University of Birmingham and University of Nottingham, the Midlands, Nottingham NG7 2UH, U.K
| | - Shailesh N Mistry
- Division of Biomolecular Science and Medicinal Chemistry, School of Pharmacy, University of Nottingham Biodiscovery Institute, University Park, Nottingham NG7 2RD, U.K
| | - Barrie Kellam
- Division of Biomolecular Science and Medicinal Chemistry, School of Pharmacy, University of Nottingham Biodiscovery Institute, University Park, Nottingham NG7 2RD, U.K.,Centre of Membrane Proteins and Receptors, University of Birmingham and University of Nottingham, the Midlands, Nottingham NG7 2UH, U.K
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4
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Borgarelli C, Klingl YE, Escamilla-Ayala A, Munck S, Van Den Bosch L, De Borggraeve WM, Ismalaj E. Lighting Up the Plasma Membrane: Development and Applications of Fluorescent Ligands for Transmembrane Proteins. Chemistry 2021; 27:8605-8641. [PMID: 33733502 DOI: 10.1002/chem.202100296] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Indexed: 12/16/2022]
Abstract
Despite the fact that transmembrane proteins represent the main therapeutic targets for decades, complete and in-depth knowledge about their biochemical and pharmacological profiling is not fully available. In this regard, target-tailored small-molecule fluorescent ligands are a viable approach to fill in the missing pieces of the puzzle. Such tools, coupled with the ability of high-precision optical techniques to image with an unprecedented resolution at a single-molecule level, helped unraveling many of the conundrums related to plasma proteins' life-cycle and druggability. Herein, we review the recent progress made during the last two decades in fluorescent ligand design and potential applications in fluorescence microscopy of voltage-gated ion channels, ligand-gated ion channels and G-coupled protein receptors.
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Affiliation(s)
- Carlotta Borgarelli
- Department of Chemistry, Molecular Design and Synthesis, KU Leuven Campus Arenberg Celestijnenlaan 200F -, box 2404, 3001, Leuven, Belgium
| | - Yvonne E Klingl
- Department of Neurosciences, Experimental Neurology and Leuven Brain Institute (LBI), KU Leuven Campus Gasthuisberg O&N5 -, box 602 Herestraat 49, 3000, Leuven, Belgium.,Laboratory of Neurobiology, VIB, Center for Brain &, Disease Research, VIB-KU Leuven Campus Gasthuisberg O&N5 -, box 602 Herestraat 49, 3000, Leuven, Belgium
| | - Abril Escamilla-Ayala
- Center for Brain & Disease Research, & VIB BioImaging Core, VIB-KU Leuven Campus Gasthuisberg O&N5 -, box 602 Herestraat 49, 3000, Leuven, Belgium.,Department of Neurosciences, Leuven Brain Institute, KU Leuven, Campus Gasthuisberg O&N5 - box 602 Herestraat 49, 3000, Leuven, Belgium
| | - Sebastian Munck
- Center for Brain & Disease Research, & VIB BioImaging Core, VIB-KU Leuven Campus Gasthuisberg O&N5 -, box 602 Herestraat 49, 3000, Leuven, Belgium.,Department of Neurosciences, Leuven Brain Institute, KU Leuven, Campus Gasthuisberg O&N5 - box 602 Herestraat 49, 3000, Leuven, Belgium
| | - Ludo Van Den Bosch
- Department of Neurosciences, Experimental Neurology and Leuven Brain Institute (LBI), KU Leuven Campus Gasthuisberg O&N5 -, box 602 Herestraat 49, 3000, Leuven, Belgium.,Laboratory of Neurobiology, VIB, Center for Brain &, Disease Research, VIB-KU Leuven Campus Gasthuisberg O&N5 -, box 602 Herestraat 49, 3000, Leuven, Belgium
| | - Wim M De Borggraeve
- Department of Chemistry, Molecular Design and Synthesis, KU Leuven Campus Arenberg Celestijnenlaan 200F -, box 2404, 3001, Leuven, Belgium
| | - Ermal Ismalaj
- Department of Chemistry, Molecular Design and Synthesis, KU Leuven Campus Arenberg Celestijnenlaan 200F -, box 2404, 3001, Leuven, Belgium
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5
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Comeo E, Trinh P, Nguyen AT, Nowell CJ, Kindon ND, Soave M, Stoddart LA, White JM, Hill SJ, Kellam B, Halls ML, May LT, Scammells PJ. Development and Application of Subtype-Selective Fluorescent Antagonists for the Study of the Human Adenosine A 1 Receptor in Living Cells. J Med Chem 2021; 64:6670-6695. [PMID: 33724031 DOI: 10.1021/acs.jmedchem.0c02067] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The adenosine A1 receptor (A1AR) is a G-protein-coupled receptor (GPCR) that provides important therapeutic opportunities for a number of conditions including congestive heart failure, tachycardia, and neuropathic pain. The development of A1AR-selective fluorescent ligands will enhance our understanding of the subcellular mechanisms underlying A1AR pharmacology facilitating the development of more efficacious and selective therapies. Herein, we report the design, synthesis, and application of a novel series of A1AR-selective fluorescent probes based on 8-functionalized bicyclo[2.2.2]octylxanthine and 3-functionalized 8-(adamant-1-yl) xanthine scaffolds. These fluorescent conjugates allowed quantification of kinetic and equilibrium ligand binding parameters using NanoBRET and visualization of specific receptor distribution patterns in living cells by confocal imaging and total internal reflection fluorescence (TIRF) microscopy. As such, the novel A1AR-selective fluorescent antagonists described herein can be applied in conjunction with a series of fluorescence-based techniques to foster understanding of A1AR molecular pharmacology and signaling in living cells.
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Affiliation(s)
- Eleonora Comeo
- Medicinal Chemistry, Monash University, Parkville, Victoria 3052, Australia.,Division of Biomolecular Sciences and Medicinal Chemistry, School of Pharmacy, Biodiscovery Institute, University of Nottingham, Nottingham NG7 2RD, United Kingdom.,Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham, B15 2TT and University of Nottingham, Birmingham NG7 2UH, United Kingdom
| | - Phuc Trinh
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Anh T Nguyen
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Cameron J Nowell
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Nicholas D Kindon
- Division of Biomolecular Sciences and Medicinal Chemistry, School of Pharmacy, Biodiscovery Institute, University of Nottingham, Nottingham NG7 2RD, United Kingdom.,Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham, B15 2TT and University of Nottingham, Birmingham NG7 2UH, United Kingdom
| | - Mark Soave
- Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, Queens Medical Centre, University of Nottingham, Nottingham NG7 2UH, United Kingdom.,Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham, B15 2TT and University of Nottingham, Birmingham NG7 2UH, United Kingdom
| | - Leigh A Stoddart
- Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, Queens Medical Centre, University of Nottingham, Nottingham NG7 2UH, United Kingdom.,Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham, B15 2TT and University of Nottingham, Birmingham NG7 2UH, United Kingdom
| | - Jonathan M White
- School of Chemistry and the Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, Victoria 3010, Australia
| | - Stephen J Hill
- Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, Queens Medical Centre, University of Nottingham, Nottingham NG7 2UH, United Kingdom.,Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham, B15 2TT and University of Nottingham, Birmingham NG7 2UH, United Kingdom
| | - Barrie Kellam
- Division of Biomolecular Sciences and Medicinal Chemistry, School of Pharmacy, Biodiscovery Institute, University of Nottingham, Nottingham NG7 2RD, United Kingdom.,Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham, B15 2TT and University of Nottingham, Birmingham NG7 2UH, United Kingdom
| | - Michelle L Halls
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Lauren T May
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Peter J Scammells
- Medicinal Chemistry, Monash University, Parkville, Victoria 3052, Australia
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6
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Stoddart LA, Kilpatrick LE, Corriden R, Kellam B, Briddon SJ, Hill SJ. Efficient G protein coupling is not required for agonist-mediated internalization and membrane reorganization of the adenosine A 3 receptor. FASEB J 2021; 35:e21211. [PMID: 33710641 PMCID: PMC9328438 DOI: 10.1096/fj.202001729rr] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Revised: 11/03/2020] [Accepted: 11/09/2020] [Indexed: 01/09/2023]
Abstract
Organization of G protein‐coupled receptors at the plasma membrane has been the focus of much recent attention. Advanced microscopy techniques have shown that these receptors can be localized to discrete microdomains and reorganization upon ligand activation is crucial in orchestrating their signaling. Here, we have compared the membrane organization and downstream signaling of a mutant (R108A, R3.50A) of the adenosine A3 receptor (A3AR) to that of the wild‐type receptor. Fluorescence Correlation Spectroscopy (FCS) studies with a fluorescent agonist (ABEA‐X‐BY630) demonstrated that both wild‐type and mutant receptors bind agonist with high affinity but in subsequent downstream signaling assays the R108A mutation abolished agonist‐mediated inhibition of cAMP production and ERK phosphorylation. In further FCS studies, both A3AR and A3AR R108A underwent similar agonist‐induced increases in receptor density and molecular brightness which were accompanied by a decrease in membrane diffusion after agonist treatment. Using bimolecular fluorescence complementation, experiments showed that the R108A mutant retained the ability to recruit β‐arrestin and these receptor/arrestin complexes displayed similar membrane diffusion and organization to that observed with wild‐type receptors. These data demonstrate that effective G protein signaling is not a prerequisite for agonist‐stimulated β‐arrestin recruitment and membrane reorganization of the A3AR.
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Affiliation(s)
- Leigh A Stoddart
- Cell Signalling and Pharmacology Research Group, Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Nottingham, UK.,Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham and University of Nottingham, Midlands, UK
| | - Laura E Kilpatrick
- Cell Signalling and Pharmacology Research Group, Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Nottingham, UK.,Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham and University of Nottingham, Midlands, UK.,School of Pharmacy, Biodiscovery Institute, University Park Nottingham, Nottingham, UK
| | - Ross Corriden
- Cell Signalling and Pharmacology Research Group, Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Nottingham, UK.,Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham and University of Nottingham, Midlands, UK
| | - Barrie Kellam
- Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham and University of Nottingham, Midlands, UK.,School of Pharmacy, Biodiscovery Institute, University Park Nottingham, Nottingham, UK
| | - Stephen J Briddon
- Cell Signalling and Pharmacology Research Group, Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Nottingham, UK.,Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham and University of Nottingham, Midlands, UK
| | - Stephen J Hill
- Cell Signalling and Pharmacology Research Group, Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Nottingham, UK.,Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham and University of Nottingham, Midlands, UK
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7
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Calebiro D, Koszegi Z, Lanoiselée Y, Miljus T, O'Brien S. G protein-coupled receptor-G protein interactions: a single-molecule perspective. Physiol Rev 2020; 101:857-906. [PMID: 33331229 DOI: 10.1152/physrev.00021.2020] [Citation(s) in RCA: 50] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
G protein-coupled receptors (GPCRs) regulate many cellular and physiological processes, responding to a diverse range of extracellular stimuli including hormones, neurotransmitters, odorants, and light. Decades of biochemical and pharmacological studies have provided fundamental insights into the mechanisms of GPCR signaling. Thanks to recent advances in structural biology, we now possess an atomistic understanding of receptor activation and G protein coupling. However, how GPCRs and G proteins interact in living cells to confer signaling efficiency and specificity remains insufficiently understood. The development of advanced optical methods, including single-molecule microscopy, has provided the means to study receptors and G proteins in living cells with unprecedented spatio-temporal resolution. The results of these studies reveal an unexpected level of complexity, whereby GPCRs undergo transient interactions among themselves as well as with G proteins and structural elements of the plasma membrane to form short-lived signaling nanodomains that likely confer both rapidity and specificity to GPCR signaling. These findings may provide new strategies to pharmaceutically modulate GPCR function, which might eventually pave the way to innovative drugs for common diseases such as diabetes or heart failure.
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Affiliation(s)
- Davide Calebiro
- Institute of Metabolism and Systems Research, University of Birmingham, Birmingham, United Kingdom; Centre of Membrane Proteins and Receptors (COMPARE), Universities of Nottingham and Birmingham, Birmingham, United Kingdom
| | - Zsombor Koszegi
- Institute of Metabolism and Systems Research, University of Birmingham, Birmingham, United Kingdom; Centre of Membrane Proteins and Receptors (COMPARE), Universities of Nottingham and Birmingham, Birmingham, United Kingdom
| | - Yann Lanoiselée
- Institute of Metabolism and Systems Research, University of Birmingham, Birmingham, United Kingdom; Centre of Membrane Proteins and Receptors (COMPARE), Universities of Nottingham and Birmingham, Birmingham, United Kingdom
| | - Tamara Miljus
- Institute of Metabolism and Systems Research, University of Birmingham, Birmingham, United Kingdom; Centre of Membrane Proteins and Receptors (COMPARE), Universities of Nottingham and Birmingham, Birmingham, United Kingdom
| | - Shannon O'Brien
- Institute of Metabolism and Systems Research, University of Birmingham, Birmingham, United Kingdom; Centre of Membrane Proteins and Receptors (COMPARE), Universities of Nottingham and Birmingham, Birmingham, United Kingdom
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8
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Robers MB, Friedman-Ohana R, Huber KVM, Kilpatrick L, Vasta JD, Berger BT, Chaudhry C, Hill S, Müller S, Knapp S, Wood KV. Quantifying Target Occupancy of Small Molecules Within Living Cells. Annu Rev Biochem 2020; 89:557-581. [PMID: 32208767 DOI: 10.1146/annurev-biochem-011420-092302] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The binding affinity and kinetics of target engagement are fundamental to establishing structure-activity relationships (SARs) for prospective therapeutic agents. Enhancing these binding parameters for operative targets, while minimizing binding to off-target sites, can translate to improved drug efficacy and a widened therapeutic window. Compound activity is typically assessed through modulation of an observed phenotype in cultured cells. Quantifying the corresponding binding properties under common cellular conditions can provide more meaningful interpretation of the cellular SAR analysis. Consequently, methods for assessing drug binding in living cells have advanced and are now integral to medicinal chemistry workflows. In this review, we survey key technological advancements that support quantitative assessments of target occupancy in cultured cells, emphasizing generalizable methodologies able to deliver analytical precision that heretofore required reductionist biochemical approaches.
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Affiliation(s)
- M B Robers
- Promega Corporation, Madison, Wisconsin 53711, USA; , ,
| | | | - K V M Huber
- Target Discovery Institute and Nuffield Department of Medicine, University of Oxford, Oxford OX3 7FZ, United Kingdom; .,Structural Genomics Consortium, Nuffield Department of Medicine, University of Oxford, Oxford OX3 7DQ, United Kingdom
| | - L Kilpatrick
- Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Nottingham NG7 2UH, United Kingdom; , .,Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham and University of Nottingham, Midlands NG7 2UH, United Kingdom
| | - J D Vasta
- Promega Corporation, Madison, Wisconsin 53711, USA; , ,
| | - B-T Berger
- Institute of Pharmaceutical Chemistry, Goethe University Frankfurt, 60438 Frankfurt, Germany; ,
| | - C Chaudhry
- Lead Discovery and Optimization, Bristol-Myers Squibb, Princeton, New Jersey 08648, USA;
| | - S Hill
- Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Nottingham NG7 2UH, United Kingdom; , .,Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham and University of Nottingham, Midlands NG7 2UH, United Kingdom
| | - S Müller
- Institute of Pharmaceutical Chemistry, Goethe University Frankfurt, 60438 Frankfurt, Germany; , .,Structural Genomics Consortium, Buchmann Institute for Life Sciences, Goethe University Frankfurt, 60438 Frankfurt, Germany;
| | - S Knapp
- Institute of Pharmaceutical Chemistry, Goethe University Frankfurt, 60438 Frankfurt, Germany; , .,Structural Genomics Consortium, Buchmann Institute for Life Sciences, Goethe University Frankfurt, 60438 Frankfurt, Germany; .,German Cancer Network (DKTK), Frankfurt/Mainz, 60438 Frankfurt, Germany.,Frankfurt Cancer Institute (FCI), Goethe University, 60596 Frankfurt am Main, Germany
| | - K V Wood
- Promega Corporation, Madison, Wisconsin 53711, USA; , , .,Current affiliation: Light Bio, Inc., Mount Horeb, Wisconsin 53572, USA;
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9
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Cooper SL, Soave M, Jörg M, Scammells PJ, Woolard J, Hill SJ. Probe dependence of allosteric enhancers on the binding affinity of adenosine A 1 -receptor agonists at rat and human A 1 -receptors measured using NanoBRET. Br J Pharmacol 2019; 176:864-878. [PMID: 30644086 PMCID: PMC6433648 DOI: 10.1111/bph.14575] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2018] [Revised: 11/02/2018] [Accepted: 12/04/2018] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND AND PURPOSE Adenosine is a local mediator that regulates a number of physiological and pathological processes via activation of adenosine A1 -receptors. The activity of adenosine can be regulated at the level of its target receptor via drugs that bind to an allosteric site on the A1 -receptor. Here, we have investigated the species and probe dependence of two allosteric modulators on the binding characteristics of fluorescent and nonfluorescent A1 -receptor agonists. EXPERIMENTAL APPROACH A Nano-luciferase (Nluc) BRET (NanoBRET) methodology was used. This used N-terminal Nluc-tagged A1 -receptors expressed in HEK293T cells in conjunction with both fluorescent A1 -receptor agonists (adenosine and NECA analogues) and a fluorescent antagonist CA200645. KEY RESULTS PD 81,723 and VCP171 elicited positive allosteric effects on the binding affinity of orthosteric agonists at both the rat and human A1 -receptors that showed clear probe dependence. Thus, the allosteric effect on the highly selective partial agonist capadenoson was much less marked than for the full agonists NECA, adenosine, and CCPA in both species. VCP171 and, to a lesser extent, PD 81,723, also increased the specific binding of three fluorescent A1 -receptor agonists in a species-dependent manner that involved increases in Bmax and pKD . CONCLUSIONS AND IMPLICATIONS These results demonstrate the power of the NanoBRET ligand-binding approach to study the effect of allosteric ligands on the binding of fluorescent agonists to the adenosine A1 -receptor in intact living cells. Furthermore, our studies suggest that VCP171 and PD 81,723 may switch a proportion of A1 -receptors to an active agonist conformation (R*).
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Affiliation(s)
- Samantha L Cooper
- Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Nottingham, UK.,Centre of Membrane Proteins and Receptors, University of Birmingham and University of Nottingham, The Midlands, UK
| | - Mark Soave
- Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Nottingham, UK.,Centre of Membrane Proteins and Receptors, University of Birmingham and University of Nottingham, The Midlands, UK
| | - Manuela Jörg
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, Australia
| | - Peter J Scammells
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, Australia
| | - Jeanette Woolard
- Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Nottingham, UK.,Centre of Membrane Proteins and Receptors, University of Birmingham and University of Nottingham, The Midlands, UK
| | - Stephen J Hill
- Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Nottingham, UK.,Centre of Membrane Proteins and Receptors, University of Birmingham and University of Nottingham, The Midlands, UK
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10
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Yoo JI, O’Malley MA. Tuning Vector Stability and Integration Frequency Elevates Functional GPCR Production and Homogeneity in Saccharomyces cerevisiae. ACS Synth Biol 2018; 7:1763-1772. [PMID: 29871481 DOI: 10.1021/acssynbio.8b00036] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Membrane proteins play a valuable role in biotechnology, yet the difficulty of producing high yields of functional membrane protein limits their use in synthetic biology. The practical application of G protein-coupled receptors in whole cell biosensors, for example, is restricted to those that are functionally produced at the cell surface in the chosen host, limiting the range of detectable molecules. Here, we present a facile approach to significantly improve the yield and homogeneity of functional membrane proteins in Saccharomyces cerevisiae by altering only the choice of expression vector. Expression of a model GPCR, the human adenosine A2a receptor, from commonly used centromeric and episomal vectors leads to low yields and cellular heterogeneity due to plasmid loss in 20-90% of the cell population. In contrast, homogeneous production of GPCR is attained using a multisite integrating vector or a novel, modified high copy vector that does not require genomic integration or addition of any selection agents. Finally, we introduce a FACS-based screen, which enables rapid isolation of cells with 4- to 15-fold increases in gene dosage and up to a 9-fold increase in functional protein yield without loss of homogeneity compared to a strain isolated through conventional, low-throughput methods. These results can be extended to improve the cellular homogeneity and yield of other membrane proteins, expanding the repertoire of useful receptors for synthetic biology applications.
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Affiliation(s)
- Justin I. Yoo
- Department of Chemical Engineering, University of California Santa Barbara, Santa Barbara, California 93106, United States
| | - Michelle A. O’Malley
- Department of Chemical Engineering, University of California Santa Barbara, Santa Barbara, California 93106, United States
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11
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Köse M, Gollos S, Karcz T, Fiene A, Heisig F, Behrenswerth A, Kieć-Kononowicz K, Namasivayam V, Müller CE. Fluorescent-Labeled Selective Adenosine A 2B Receptor Antagonist Enables Competition Binding Assay by Flow Cytometry. J Med Chem 2018; 61:4301-4316. [PMID: 29681156 DOI: 10.1021/acs.jmedchem.7b01627] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Fluorescent ligands represent powerful tools for biological studies and are considered attractive alternatives to radioligands. In this study, we developed fluorescent antagonists for A2B adenosine receptors (A2BARs), which are targeted by antiasthmatic xanthines and were proposed as novel targets in immuno-oncology. Our approach was to merge a small borondipyrromethene (BODIPY) derivative with the pharmacophore of 8-substituted xanthine derivatives. On the basis of the design, synthesis, and evaluation of model compounds, several fluorescent ligands were synthesized. Compound 29 (PSB-12105), which displayed high affinity for human, rat, and mouse A2BARs ( Ki = 0.2-2 nM) and high selectivity for this AR subtype, was selected for further studies. A homology model of the human A2BAR was generated, and docking studies were performed. Moreover, 29 allowed us to establish a homogeneous receptor-ligand binding assay using flow cytometry. These compounds constitute the first potent, selective fluorescent A2BAR ligands and are anticipated to be useful for a variety of applications.
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Affiliation(s)
- Meryem Köse
- PharmaCenter Bonn, Pharmaceutical Institute, Pharmaceutical Chemistry I , University of Bonn , An der Immenburg 4 , D-53121 Bonn , Germany
| | - Sabrina Gollos
- PharmaCenter Bonn, Pharmaceutical Institute, Pharmaceutical Chemistry I , University of Bonn , An der Immenburg 4 , D-53121 Bonn , Germany
| | - Tadeusz Karcz
- Department of Technology and Biotechnology of Drugs, Faculty of Pharmacy , Jagiellonian University Medical College , Medyczna 9 , 30-688 Kraków , Poland
| | - Amelie Fiene
- PharmaCenter Bonn, Pharmaceutical Institute, Pharmaceutical Chemistry I , University of Bonn , An der Immenburg 4 , D-53121 Bonn , Germany
| | - Fabian Heisig
- PharmaCenter Bonn, Pharmaceutical Institute, Pharmaceutical Chemistry I , University of Bonn , An der Immenburg 4 , D-53121 Bonn , Germany
| | - Andrea Behrenswerth
- PharmaCenter Bonn, Pharmaceutical Institute, Pharmaceutical Chemistry I , University of Bonn , An der Immenburg 4 , D-53121 Bonn , Germany
| | - Katarzyna Kieć-Kononowicz
- Department of Technology and Biotechnology of Drugs, Faculty of Pharmacy , Jagiellonian University Medical College , Medyczna 9 , 30-688 Kraków , Poland
| | - Vigneshwaran Namasivayam
- PharmaCenter Bonn, Pharmaceutical Institute, Pharmaceutical Chemistry I , University of Bonn , An der Immenburg 4 , D-53121 Bonn , Germany
| | - Christa E Müller
- PharmaCenter Bonn, Pharmaceutical Institute, Pharmaceutical Chemistry I , University of Bonn , An der Immenburg 4 , D-53121 Bonn , Germany
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12
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Briddon SJ, Kilpatrick LE, Hill SJ. Studying GPCR Pharmacology in Membrane Microdomains: Fluorescence Correlation Spectroscopy Comes of Age. Trends Pharmacol Sci 2017; 39:158-174. [PMID: 29277246 DOI: 10.1016/j.tips.2017.11.004] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2017] [Revised: 11/13/2017] [Accepted: 11/14/2017] [Indexed: 12/17/2022]
Abstract
G protein-coupled receptors (GPCRs) are organised within the cell membrane into highly ordered macromolecular complexes along with other receptors and signalling proteins. Understanding how heterogeneity in these complexes affects the pharmacology and functional response of these receptors is crucial for developing new and more selective ligands. Fluorescence correlation spectroscopy (FCS) and related techniques such as photon counting histogram (PCH) analysis and image-based FCS can be used to interrogate the properties of GPCRs in these membrane microdomains, as well as their interaction with fluorescent ligands. FCS analyses fluorescence fluctuations within a small-defined excitation volume to yield information about their movement, concentration and molecular brightness (aggregation). These techniques can be used on live cells with single-molecule sensitivity and high spatial resolution. Once the preserve of specialist equipment, FCS techniques can now be applied using standard confocal microscopes. This review describes how FCS and related techniques have revealed novel insights into GPCR biology.
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Affiliation(s)
- Stephen J Briddon
- Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Nottingham, NG7 2UH, UK; Centre for Membrane Proteins and Receptors (COMPARE), University of Birmingham and University of Nottingham, The Midlands, UK
| | - Laura E Kilpatrick
- Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Nottingham, NG7 2UH, UK; Centre for Membrane Proteins and Receptors (COMPARE), University of Birmingham and University of Nottingham, The Midlands, UK
| | - Stephen J Hill
- Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Nottingham, NG7 2UH, UK; Centre for Membrane Proteins and Receptors (COMPARE), University of Birmingham and University of Nottingham, The Midlands, UK.
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13
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Soave M, Cseke G, Hutchings CJ, Brown AJH, Woolard J, Hill SJ. A monoclonal antibody raised against a thermo-stabilised β 1-adrenoceptor interacts with extracellular loop 2 and acts as a negative allosteric modulator of a sub-set of β 1-adrenoceptors expressed in stable cell lines. Biochem Pharmacol 2017; 147:38-54. [PMID: 29102678 PMCID: PMC5770334 DOI: 10.1016/j.bcp.2017.10.015] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2017] [Accepted: 10/31/2017] [Indexed: 11/30/2022]
Abstract
Recent interest has focused on antibodies that can discriminate between different receptor conformations. Here we have characterised the effect of a monoclonal antibody (mAb3), raised against a purified thermo-stabilised turkey β1-adrenoceptor (β1AR-m23 StaR), on β1-ARs expressed in CHO-K1 or HEK 293 cells. Immunohistochemical and radioligand-binding studies demonstrated that mAb3 was able to bind to ECL2 of the tβ1-AR, but not its human homologue. Specific binding of mAb3 to tβ1-AR was inhibited by a peptide based on the turkey, but not the human, ECL2 sequence. Studies with [3H]-CGP 12177 demonstrated that mAb3 prevented the binding of orthosteric ligands to a subset (circa 40%) of turkey β1-receptors expressed in both CHO K1 and HEK 293 cells. MAb3 significantly reduced the maximum specific binding capacity of [3H]-CGP-12177 without influencing its binding affinity. Substitution of ECL2 of tβ1-AR with its human equivalent, or mutation of residues D186S, P187D, Q188E prevented the inhibition of [3H]-CGP 12177 binding by mAb3. MAb3 also elicited a negative allosteric effect on agonist-stimulated cAMP responses. The identity of the subset of turkey β1-adrenoceptors influenced by mAb3 remains to be established but mAb3 should become an important tool to investigate the nature of β1-AR conformational states and oligomeric complexes.
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Affiliation(s)
- Mark Soave
- Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Nottingham NG7 2UH, UK; Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham and University of Nottingham, Midlands, UK
| | - Gabriella Cseke
- Heptares Therapeutics Ltd., Bio Park, Welwyn Garden City AL7 3AX, UK
| | | | | | - Jeanette Woolard
- Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Nottingham NG7 2UH, UK; Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham and University of Nottingham, Midlands, UK.
| | - Stephen J Hill
- Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Nottingham NG7 2UH, UK; Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham and University of Nottingham, Midlands, UK.
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14
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Leiva A, Guzmán-Gutiérrez E, Contreras-Duarte S, Fuenzalida B, Cantin C, Carvajal L, Salsoso R, Gutiérrez J, Pardo F, Sobrevia L. Adenosine receptors: Modulators of lipid availability that are controlled by lipid levels. Mol Aspects Med 2017; 55:26-44. [DOI: 10.1016/j.mam.2017.01.007] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2016] [Revised: 01/25/2017] [Accepted: 01/25/2017] [Indexed: 12/20/2022]
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15
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The use of fluorescence correlation spectroscopy to characterize the molecular mobility of fluorescently labelled G protein-coupled receptors. Biochem Soc Trans 2016; 44:624-9. [PMID: 27068980 PMCID: PMC5264494 DOI: 10.1042/bst20150285] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2016] [Indexed: 01/10/2023]
Abstract
The membranes of living cells have been shown to be highly organized into distinct microdomains, which has spatial and temporal consequences for the interaction of membrane bound receptors and their signalling partners as complexes. Fluorescence correlation spectroscopy (FCS) is a technique with single cell sensitivity that sheds light on the molecular dynamics of fluorescently labelled receptors, ligands or signalling complexes within small plasma membrane regions of living cells. This review provides an overview of the use of FCS to probe the real time quantification of the diffusion and concentration of G protein-coupled receptors (GPCRs), primarily to gain insights into ligand–receptor interactions and the molecular composition of signalling complexes. In addition we document the use of photon counting histogram (PCH) analysis to investigate how changes in molecular brightness (ε) can be a sensitive indicator of changes in molecular mass of fluorescently labelled moieties.
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16
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Tian H, Fürstenberg A, Huber T. Labeling and Single-Molecule Methods To Monitor G Protein-Coupled Receptor Dynamics. Chem Rev 2016; 117:186-245. [DOI: 10.1021/acs.chemrev.6b00084] [Citation(s) in RCA: 84] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Affiliation(s)
- He Tian
- Laboratory of Chemical Biology
and Signal Transduction, The Rockefeller University, 1230 York
Avenue, New York, New York 10065, United States
| | - Alexandre Fürstenberg
- Laboratory of Chemical Biology
and Signal Transduction, The Rockefeller University, 1230 York
Avenue, New York, New York 10065, United States
| | - Thomas Huber
- Laboratory of Chemical Biology
and Signal Transduction, The Rockefeller University, 1230 York
Avenue, New York, New York 10065, United States
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17
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Guo D, Heitman LH, IJzerman AP. Kinetic Aspects of the Interaction between Ligand and G Protein-Coupled Receptor: The Case of the Adenosine Receptors. Chem Rev 2016; 117:38-66. [DOI: 10.1021/acs.chemrev.6b00025] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Dong Guo
- Division of Medicinal Chemistry,
Leiden Academic Centre for Drug Research (LACDR), Leiden University, P.O. Box 9502, 2300 RA Leiden, The Netherlands
| | - Laura H. Heitman
- Division of Medicinal Chemistry,
Leiden Academic Centre for Drug Research (LACDR), Leiden University, P.O. Box 9502, 2300 RA Leiden, The Netherlands
| | - Adriaan P. IJzerman
- Division of Medicinal Chemistry,
Leiden Academic Centre for Drug Research (LACDR), Leiden University, P.O. Box 9502, 2300 RA Leiden, The Netherlands
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18
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Knight A, Hemmings JL, Winfield I, Leuenberger M, Frattini E, Frenguelli BG, Dowell SJ, Lochner M, Ladds G. Discovery of Novel Adenosine Receptor Agonists That Exhibit Subtype Selectivity. J Med Chem 2016; 59:947-64. [DOI: 10.1021/acs.jmedchem.5b01402] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Affiliation(s)
- Anthony Knight
- Systems
Biology Doctoral Training Centre, University of Warwick, Coventry CV4 7AL, U.K
| | - Jennifer L. Hemmings
- Department
of Chemistry and Biochemistry, University of Bern, 3012 Bern, Switzerland
| | - Ian Winfield
- Division
of Biomedical Cell Biology, Warwick Medical School, University of Warwick, Coventry CV4 7AL, U.K
- Department
of Pharmacology, University of Cambridge, Tennis Court Road, Cambridge CB2 1PD, U.K
| | - Michele Leuenberger
- Department
of Chemistry and Biochemistry, University of Bern, 3012 Bern, Switzerland
| | - Eugenia Frattini
- Department
of Pharmacology, University of Cambridge, Tennis Court Road, Cambridge CB2 1PD, U.K
| | | | - Simon J. Dowell
- Department
of Platform Technology and Science, GlaxoSmithKline, Hertfordshire SG1 2NY, U.K
| | - Martin Lochner
- Department
of Chemistry and Biochemistry, University of Bern, 3012 Bern, Switzerland
| | - Graham Ladds
- Department
of Pharmacology, University of Cambridge, Tennis Court Road, Cambridge CB2 1PD, U.K
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19
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Scarselli M, Annibale P, McCormick PJ, Kolachalam S, Aringhieri S, Radenovic A, Corsini GU, Maggio R. Revealing G-protein-coupled receptor oligomerization at the single-molecule level through a nanoscopic lens: methods, dynamics and biological function. FEBS J 2015; 283:1197-217. [PMID: 26509747 DOI: 10.1111/febs.13577] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2015] [Revised: 09/29/2015] [Accepted: 10/23/2015] [Indexed: 11/30/2022]
Abstract
The introduction of super-resolution fluorescence microscopy has allowed the visualization of single proteins in their biological environment. Recently, these techniques have been applied to determine the organization of class A G-protein-coupled receptors (GPCRs), and to determine whether they exist as monomers, dimers and/or higher-order oligomers. On this subject, this review highlights recent evidence from photoactivated localization microscopy (PALM), which allows the visualization of single molecules in dense samples, and single-molecule tracking (SMT), which determines how GPCRs move and interact in living cells in the presence of different ligands. PALM has demonstrated that GPCR oligomerization depends on the receptor subtype, the cell type, the actin cytoskeleton, and other proteins. Conversely, SMT has revealed the transient dynamics of dimer formation, whereby receptors show a monomer-dimer equilibrium characterized by rapid association and dissociation. At steady state, depending on the subtype, approximately 30-50% of receptors are part of dimeric complexes. Notably, the existence of many GPCR dimers/oligomers is also supported by well-known techniques, such as resonance energy transfer methodologies, and by approaches that exploit fluorescence fluctuations, such as fluorescence correlation spectroscopy (FCS). Future research using single-molecule methods will deepen our knowledge related to the function and druggability of homo-oligomers and hetero-oligomers.
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Affiliation(s)
- Marco Scarselli
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Italy
| | - Paolo Annibale
- Laboratory of Nanoscale Biology, Institute of Bioengineering, School of Engineering, EPFL, Lausanne, Switzerland
| | | | - Shivakumar Kolachalam
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Italy
| | - Stefano Aringhieri
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Italy
| | - Aleksandra Radenovic
- Laboratory of Nanoscale Biology, Institute of Bioengineering, School of Engineering, EPFL, Lausanne, Switzerland
| | - Giovanni U Corsini
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Italy
| | - Roberto Maggio
- Biotechnological and Applied Clinical Sciences Department, University of L'Aquila, Italy
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20
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Hoffmann C, Castro M, Rinken A, Leurs R, Hill SJ, Vischer HF. Ligand Residence Time at G-protein–Coupled Receptors—Why We Should Take Our Time To Study It. Mol Pharmacol 2015; 88:552-60. [DOI: 10.1124/mol.115.099671] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2015] [Accepted: 07/07/2015] [Indexed: 12/15/2022] Open
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21
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Vischer HF, Castro M, Pin JP. G Protein-Coupled Receptor Multimers: A Question Still Open Despite the Use of Novel Approaches. Mol Pharmacol 2015; 88:561-71. [PMID: 26138074 DOI: 10.1124/mol.115.099440] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2015] [Accepted: 07/02/2015] [Indexed: 12/11/2022] Open
Abstract
Heteromerization of G protein-coupled receptors (GPCRs) can significantly change the functional properties of involved receptors. Various biochemical and biophysical methodologies have been developed in the last two decades to identify and functionally evaluate GPCR heteromers in heterologous cells, with recent approaches focusing on GPCR complex stoichiometry and stability. Yet validation of these observations in native tissues is still lagging behind for the majority of GPCR heteromers. Remarkably, recent studies, particularly some involving advanced fluorescence microscopy techniques, are contributing to our current knowledge of aspects that were not well known until now, such as GPCR complex stoichiometry and stability. In parallel, a growing effort is being applied to move the field forward into native systems. This short review will highlight recent developments to study the stoichiometry and stability of GPCR complexes and methodologies to detect native GPCR dimers.
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Affiliation(s)
- Henry F Vischer
- Amsterdam Institute for Molecules, Medicines and Systems, Division of Medicinal Chemistry, Faculty of Sciences, VU University Amsterdam, Amsterdam, The Netherlands (H.F.V.); Molecular Pharmacology Laboratory, Biofarma Research Group (GI-1685), University of Santiago de Compostela, Center for Research in Molecular Medicine and Chronic Diseases, Santiago de Compostela, Spain (M.C.); and Centre National de la Recherche Scientifique, Institut de Génomique Fonctionnelle, Université de Montpellier, Montpellier, France (J.-P.P.)
| | - Marián Castro
- Amsterdam Institute for Molecules, Medicines and Systems, Division of Medicinal Chemistry, Faculty of Sciences, VU University Amsterdam, Amsterdam, The Netherlands (H.F.V.); Molecular Pharmacology Laboratory, Biofarma Research Group (GI-1685), University of Santiago de Compostela, Center for Research in Molecular Medicine and Chronic Diseases, Santiago de Compostela, Spain (M.C.); and Centre National de la Recherche Scientifique, Institut de Génomique Fonctionnelle, Université de Montpellier, Montpellier, France (J.-P.P.)
| | - Jean-Philippe Pin
- Amsterdam Institute for Molecules, Medicines and Systems, Division of Medicinal Chemistry, Faculty of Sciences, VU University Amsterdam, Amsterdam, The Netherlands (H.F.V.); Molecular Pharmacology Laboratory, Biofarma Research Group (GI-1685), University of Santiago de Compostela, Center for Research in Molecular Medicine and Chronic Diseases, Santiago de Compostela, Spain (M.C.); and Centre National de la Recherche Scientifique, Institut de Génomique Fonctionnelle, Université de Montpellier, Montpellier, France (J.-P.P.)
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22
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Stoddart LA, Kilpatrick LE, Briddon SJ, Hill SJ. Probing the pharmacology of G protein-coupled receptors with fluorescent ligands. Neuropharmacology 2015; 98:48-57. [PMID: 25979488 DOI: 10.1016/j.neuropharm.2015.04.033] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2015] [Revised: 04/23/2015] [Accepted: 04/29/2015] [Indexed: 01/01/2023]
Abstract
G protein-coupled receptors control a wide range of physiological processes and are the target for many clinically used drugs. Understanding the way in which receptors bind agonists and antagonists, their organisation in the membrane and their regulation after agonist binding are important properties which are key to developing new drugs. One way to achieve this knowledge is through the use of fluorescent ligands, which have been used to study the expression and function of receptors in endogenously expressing systems. Fluorescent ligands with appropriate imaging properties can be used in conjunction with confocal microscopy to investigate the regulation of receptors after activation. Alternatively, through the use of single molecule microscopy, they can probe the spatial organisation of receptors within the membrane. This review focuses on the techniques in which fluorescent ligands have been used and the novel aspects of G protein-coupled receptor pharmacology which have been uncovered. This article is part of the Special Issue entitled 'Fluorescent Tools in Neuropharmacology'.
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Affiliation(s)
- Leigh A Stoddart
- Cell Signalling Research Group, School of Life Sciences, University of Nottingham, Nottingham, UK
| | - Laura E Kilpatrick
- Cell Signalling Research Group, School of Life Sciences, University of Nottingham, Nottingham, UK
| | - Stephen J Briddon
- Cell Signalling Research Group, School of Life Sciences, University of Nottingham, Nottingham, UK
| | - Stephen J Hill
- Cell Signalling Research Group, School of Life Sciences, University of Nottingham, Nottingham, UK
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23
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Ciruela F, Fernández-Dueñas V, Jacobson KA. Lighting up G protein-coupled purinergic receptors with engineered fluorescent ligands. Neuropharmacology 2015; 98:58-67. [PMID: 25890205 DOI: 10.1016/j.neuropharm.2015.04.001] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2015] [Revised: 03/23/2015] [Accepted: 04/01/2015] [Indexed: 12/31/2022]
Abstract
The use of G protein-coupled receptors fluorescent ligands is undergoing continuous expansion. In line with this, fluorescent agonists and antagonists of high affinity for G protein-coupled adenosine and P2Y receptors have been shown to be useful pharmacological probe compounds. Fluorescent ligands for A1R, A2AR, and A3R (adenosine receptors) and P2Y2R, P2Y4R, P2Y6R, and P2Y14R (nucleotide receptors) have been reported. Such ligands have been successfully applied to drug discovery and to GPCR characterization by flow cytometry, fluorescence correlation spectroscopy, fluorescence microscopy, fluorescence polarization, fluorescence resonance energy transfer and scanning confocal microscopy. Here we summarize recently reported and readily available representative fluorescent ligands of purinergic receptors. In addition, we pay special attention on the use of this family of fluorescent ligands revealing two main aspects of purinergic receptor biology, namely ligand binding and receptor oligomerization. This article is part of the Special Issue entitled 'Fluorescent Tools in Neuropharmacology'.
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Affiliation(s)
- Francisco Ciruela
- Unitat de Farmacologia, Departament Patologia i Terapèutica Experimental, Facultat de Medicina, IDIBELL, Universitat de Barcelona, 08907 L'Hospitalet de Llobregat, Spain; Department of Physiology, Faculty of Sciences, University of Ghent, 9000 Gent, Belgium.
| | - Víctor Fernández-Dueñas
- Unitat de Farmacologia, Departament Patologia i Terapèutica Experimental, Facultat de Medicina, IDIBELL, Universitat de Barcelona, 08907 L'Hospitalet de Llobregat, Spain
| | - Kenneth A Jacobson
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, 20892 Bethesda, USA.
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Godinho RO, Duarte T, Pacini ESA. New perspectives in signaling mediated by receptors coupled to stimulatory G protein: the emerging significance of cAMP efflux and extracellular cAMP-adenosine pathway. Front Pharmacol 2015; 6:58. [PMID: 25859216 PMCID: PMC4373373 DOI: 10.3389/fphar.2015.00058] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2015] [Accepted: 03/06/2015] [Indexed: 12/25/2022] Open
Abstract
G protein-coupled receptors (GPCRs) linked to stimulatory G (Gs) proteins (GsPCRs) mediate increases in intracellular cyclic AMP as consequence of activation of nine adenylyl cyclases , which differ considerably in their cellular distribution and activation mechanisms. Once produced, cyclic AMP may act via distinct intracellular signaling effectors such as protein kinase A and the exchange proteins activated by cAMP (Epacs). More recently, attention has been focused on the efflux of cAMP through a specific transport system named multidrug resistance proteins that belongs to the ATP-binding cassette transporter superfamily. Outside the cell, cAMP is metabolized into adenosine, which is able to activate four distinct subtypes of adenosine receptors, members of the GPCR family: A1, A2A, A2B, and A3. Taking into account that this phenomenon occurs in numerous cell types, as consequence of GsPCR activation and increment in intracellular cAMP levels, in this review, we will discuss the impact of cAMP efflux and the extracellular cAMP-adenosine pathway on the regulation of GsPCR-induced cell response.
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Affiliation(s)
- Rosely O Godinho
- Disciplina Farmacologia Celular, Departamento de Farmacologia, Escola Paulista de Medicina, Universidade Federal de São Paulo São Paulo, Brazil
| | - Thiago Duarte
- Disciplina Farmacologia Celular, Departamento de Farmacologia, Escola Paulista de Medicina, Universidade Federal de São Paulo São Paulo, Brazil
| | - Enio S A Pacini
- Disciplina Farmacologia Celular, Departamento de Farmacologia, Escola Paulista de Medicina, Universidade Federal de São Paulo São Paulo, Brazil
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25
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Hill S. Investigation of GPCR allosterism and dimerization in single living cells using fluorescent ligands. SPRINGERPLUS 2015; 4:L8. [PMID: 27386225 PMCID: PMC4797649 DOI: 10.1186/2193-1801-4-s1-l8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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26
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Ma Z, Du L, Li M. Toward fluorescent probes for G-protein-coupled receptors (GPCRs). J Med Chem 2014; 57:8187-203. [PMID: 24983484 DOI: 10.1021/jm401823z] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
G-protein-coupled receptors (GPCRs), a superfamily of cell-surface receptors that are the targets of about 40% of prescription drugs on the market, can sense numerous critical extracellular signals. Recent breakthroughs in structural biology, especially in holo-form X-ray crystal structures, have contributed to our understanding of GPCR signaling. However, actions of GPCRs at the cellular and molecular level, interactions between GPCRs, and the role of protein dynamics in receptor activities still remain controversial. To overcome these dilemmas, fluorescent probes of GPCRs have been employed, which have advantages of in vivo safety and real-time monitoring. Various probes that depend on specific mechanisms and/or technologies have been used to study GPCRs. The present review focuses on surveying the design and applications of fluorescent probes for GPCRs that are derived from small molecules or using protein-labeling techniques, as well as discussing some design strategies for new probes.
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Affiliation(s)
- Zhao Ma
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (MOE), School of Pharmacy, Shandong University , Jinan, Shandong 250012, China
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Corriden R, Kilpatrick LE, Kellam B, Briddon SJ, Hill SJ. Kinetic analysis of antagonist-occupied adenosine-A3 receptors within membrane microdomains of individual cells provides evidence of receptor dimerization and allosterism. FASEB J 2014; 28:4211-22. [PMID: 24970394 PMCID: PMC4202110 DOI: 10.1096/fj.13-247270] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
In our previous work, using a fluorescent adenosine-A3 receptor (A3AR) agonist and fluorescence correlation spectroscopy (FCS), we demonstrated high-affinity labeling of the active receptor (R*) conformation. In the current study, we used a fluorescent A3AR antagonist (CA200645) to study the binding characteristics of antagonist-occupied inactive receptor (R) conformations in membrane microdomains of individual cells. FCS analysis of CA200645-occupied A3ARs revealed 2 species, τD2 and τD3, that diffused at 2.29 ± 0.35 and 0.09 ± 0.03 μm(2)/s, respectively. FCS analysis of a green fluorescent protein (GFP)-tagged A3AR exhibited a single diffusing species (0.105 μm(2)/s). The binding of CA200645 to τD3 was antagonized by nanomolar concentrations of the A3 antagonist MRS 1220, but not by the agonist NECA (up to 300 nM), consistent with labeling of R. CA200645 normally dissociated slowly from the A3AR, but inclusion of xanthine amine congener (XAC) or VUF 5455 during washout markedly accelerated the reduction in the number of particles exhibiting τD3 characteristics. It is notable that this effect was accompanied by a significant increase in the number of particles with τD2 diffusion. These data show that FCS analysis of ligand-occupied receptors provides a unique means of monitoring ligand A3AR residence times that are significantly reduced as a consequence of allosteric interaction across the dimer interface
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Affiliation(s)
- Ross Corriden
- Institute of Cell Signalling, School of Life Sciences, Medical School, and
| | - Laura E Kilpatrick
- Institute of Cell Signalling, School of Life Sciences, Medical School, and
| | - Barrie Kellam
- School of Pharmacy, Centre for Biomolecular Sciences, University of Nottingham, Nottingham, UK
| | - Stephen J Briddon
- Institute of Cell Signalling, School of Life Sciences, Medical School, and
| | - Stephen J Hill
- Institute of Cell Signalling, School of Life Sciences, Medical School, and
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28
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Sridharan R, Zuber J, Connelly SM, Mathew E, Dumont ME. Fluorescent approaches for understanding interactions of ligands with G protein coupled receptors. BIOCHIMICA ET BIOPHYSICA ACTA 2014; 1838:15-33. [PMID: 24055822 PMCID: PMC3926105 DOI: 10.1016/j.bbamem.2013.09.005] [Citation(s) in RCA: 86] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2013] [Revised: 09/03/2013] [Accepted: 09/08/2013] [Indexed: 11/18/2022]
Abstract
G protein coupled receptors are responsible for a wide variety of signaling responses in diverse cell types. Despite major advances in the determination of structures of this class of receptors, the underlying mechanisms by which binding of different types of ligands specifically elicits particular signaling responses remain unclear. The use of fluorescence spectroscopy can provide important information about the process of ligand binding and ligand dependent conformational changes in receptors, especially kinetic aspects of these processes that can be difficult to extract from X-ray structures. We present an overview of the extensive array of fluorescent ligands that have been used in studies of G protein coupled receptors and describe spectroscopic approaches for assaying binding and probing the environment of receptor-bound ligands with particular attention to examples involving yeast pheromone receptors. In addition, we discuss the use of fluorescence spectroscopy for detecting and characterizing conformational changes in receptors induced by the binding of ligands. Such studies have provided strong evidence for diversity of receptor conformations elicited by different ligands, consistent with the idea that GPCRs are not simple on and off switches. This diversity of states constitutes an underlying mechanistic basis for biased agonism, the observation that different stimuli can produce different responses from a single receptor. It is likely that continued technical advances will allow fluorescence spectroscopy to play an important role in continued probing of structural transitions in G protein coupled receptors. This article is part of a Special Issue entitled: Structural and biophysical characterisation of membrane protein-ligand binding.
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Affiliation(s)
- Rajashri Sridharan
- Department of Biochemistry and Biophysics, P.O. Box 712, University of Rochester Medical Center, Rochester, NY 14642
| | - Jeffrey Zuber
- Department of Biochemistry and Biophysics, P.O. Box 712, University of Rochester Medical Center, Rochester, NY 14642
| | - Sara M. Connelly
- Department of Biochemistry and Biophysics, P.O. Box 712, University of Rochester Medical Center, Rochester, NY 14642
| | - Elizabeth Mathew
- Department of Biochemistry and Biophysics, P.O. Box 712, University of Rochester Medical Center, Rochester, NY 14642
| | - Mark E. Dumont
- Department of Biochemistry and Biophysics, P.O. Box 712, University of Rochester Medical Center, Rochester, NY 14642
- Department of Pediatrics, P.O. Box 777, University of Rochester Medical Center, Rochester, NY 14642
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29
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Jaeger WC, Armstrong SP, Hill SJ, Pfleger KDG. Biophysical Detection of Diversity and Bias in GPCR Function. Front Endocrinol (Lausanne) 2014; 5:26. [PMID: 24634666 PMCID: PMC3943086 DOI: 10.3389/fendo.2014.00026] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/06/2014] [Accepted: 02/19/2014] [Indexed: 12/27/2022] Open
Abstract
Guanine nucleotide binding protein (G protein)-coupled receptors (GPCRs) function in complexes with a range of molecules and proteins including ligands, G proteins, arrestins, ubiquitin, and other receptors. Elements of these complexes may interact constitutively or dynamically, dependent upon factors such as ligand binding, phosphorylation, and dephosphorylation. They may also be allosterically modulated by other proteins in a manner that changes temporally and spatially within the cell. Elucidating how these complexes function has been greatly enhanced by biophysical technologies that are able to monitor proximity and/or binding, often in real time and in live cells. These include resonance energy transfer approaches such as bioluminescence resonance energy transfer (BRET) and fluorescence resonance energy transfer (FRET). Furthermore, the use of fluorescent ligands has enabled novel insights into allosteric interactions between GPCRs. Consequently, biophysical approaches are helping to unlock the amazing diversity and bias in G protein-coupled receptor signaling.
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Affiliation(s)
- Werner C. Jaeger
- Molecular Endocrinology and Pharmacology, Harry Perkins Institute of Medical Research and Centre for Medical Research, The University of Western Australia, Perth, WA, Australia
| | - Stephen P. Armstrong
- Molecular Endocrinology and Pharmacology, Harry Perkins Institute of Medical Research and Centre for Medical Research, The University of Western Australia, Perth, WA, Australia
| | - Stephen J. Hill
- Cell Signalling Research Group, School of Life Sciences, Queen’s Medical Centre, University of Nottingham Medical School, Nottingham, UK
| | - Kevin D. G. Pfleger
- Molecular Endocrinology and Pharmacology, Harry Perkins Institute of Medical Research and Centre for Medical Research, The University of Western Australia, Perth, WA, Australia
- Dimerix Bioscience Pty Ltd, Perth, WA, Australia
- *Correspondence: Kevin D. G. Pfleger, Molecular Endocrinology and Pharmacology, Harry Perkins Institute of Medical Research and Centre for Medical Research, The University of Western Australia, QEII Medical Centre, QQ Block, 6 Verdun Street, Nedlands, Perth, WA 6009, Australia e-mail:
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30
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Heisig F, Gollos S, Freudenthal SJ, El-Tayeb A, Iqbal J, Müller CE. Synthesis of BODIPY derivatives substituted with various bioconjugatable linker groups: a construction kit for fluorescent labeling of receptor ligands. J Fluoresc 2013; 24:213-30. [PMID: 24052460 DOI: 10.1007/s10895-013-1289-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2013] [Accepted: 08/09/2013] [Indexed: 12/15/2022]
Abstract
The goal of the present study was to design small, functionalized green-emitting BODIPY dyes, which can readily be coupled to target molecules such as receptor ligands, or even be integrated into their pharmacophores. A simple two-step one-pot procedure starting from 2,4-dimethylpyrrole and ω-bromoalkylcarboxylic acid chlorides was used to obtain new ω-bromoalkyl-substituted BODIPY fluorophores (1a-1f) connected via alkyl spacers of different length to the 8-position of the fluorescent dye. The addition of radical inhibitors reduced the amount of side products. The ω-bromoalkyl-substituted BODIPYs were further converted to introduce various functional groups: iodo-substituted dyes were obtained by Finkelstein reaction in excellent yields; microwave-assisted reaction with methanolic ammonia led to fast and clean conversion to the amino-substituted dyes; a hydroxyl-substituted derivative was prepared by reaction with sodium ethylate, and thiol-substituted BODIPYs were obtained by reaction of 1a-1f with potassium thioacetate followed by alkaline cleavage of the thioesters. Water-soluble derivatives were prepared by introducing sulfonate groups into the 2- and 6-position of the BODIPY core. The synthesized BODIPY derivatives showed high fluorescent yields and appeared to be stable under basic, reducing and oxidative conditions. As a proof of concept, 2-thioadenosine was alkylated with bromoethyl-BODIPY 1b. The resulting fluorescent 2-substituted adenosine derivative 15 displayed selectivity for the A3 adenosine receptor (ARs) over the other AR subtypes, showed agonistic activity, and may thus become a useful tool for studying A3ARs, or a lead structure for further optimization. The new functionalized dyes may be widely used for fluorescent labeling allowing the investigation of biological targets and processes.
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Affiliation(s)
- Fabian Heisig
- PharmaCenter Bonn, Pharmaceutical Institute, Pharmaceutical Chemistry I, University Bonn, 53121, Bonn, Germany
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31
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Kozma E, Gizewski ET, Tosh DK, Squarcialupi L, Auchampach JA, Jacobson KA. Characterization by flow cytometry of fluorescent, selective agonist probes of the A(3) adenosine receptor. Biochem Pharmacol 2013; 85:1171-81. [PMID: 23376019 DOI: 10.1016/j.bcp.2013.01.021] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2012] [Revised: 01/16/2013] [Accepted: 01/24/2013] [Indexed: 01/02/2023]
Abstract
Various fluorescent nucleoside agonists of the A3 adenosine receptor (AR) were compared as high affinity probes using radioligands and flow cytometry (FCM). They contained a fluorophore linked through the C2 or N(6) position and rigid A3AR-enhancing (N)-methanocarba modification. A hydrophobic C2-(1-pyrenyl) derivative MRS5704 bound nonselectively. C2-Tethered cyanine5-dye labeled MRS5218 bound selectively to hA3AR expressed in whole CHO cells and membranes. By FCM, binding was A3AR-mediated (blocked by A3AR antagonist, at least half through internalization), with t1/2 for association 38min in mA3AR-HEK293 cells; 26.4min in sucrose-treated hA3AR-CHO cells (Kd 31nM). Membrane binding indicated moderate mA3AR affinity, but not selectivity. Specific accumulation of fluorescence (50nM MRS5218) occurred in cells expressing mA3AR, but not other mouse ARs. Evidence was provided suggesting that MRS5218 detects endogenous expression of the A3AR in the human promyelocytic leukemic HL-60 cell line. Therefore, MRS5218 promises to be a useful tool for characterizing the A3AR.
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Affiliation(s)
- Eszter Kozma
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892-0810, USA
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32
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Kozma E, Jayasekara PS, Squarcialupi L, Paoletta S, Moro S, Federico S, Spalluto G, Jacobson KA. Fluorescent ligands for adenosine receptors. Bioorg Med Chem Lett 2013; 23:26-36. [PMID: 23200243 PMCID: PMC3557833 DOI: 10.1016/j.bmcl.2012.10.112] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2012] [Revised: 10/05/2012] [Accepted: 10/28/2012] [Indexed: 10/27/2022]
Abstract
Interest is increasing in developing fluorescent ligands for characterization of adenosine receptors (ARs), which hold a promise of usefulness in the drug discovery process. The size of a strategically labeled AR ligand can be greatly increased after the attachment of a fluorophore. The choice of dye moiety (e.g. Alexa Fluor 488), attachment point and linker length can alter the selectivity and potency of the parent molecule. Fluorescent derivatives of adenosine agonists and antagonists (e.g. XAC and other heterocyclic antagonist scaffolds) have been synthesized and characterized pharmacologically. Some are useful AR probes for flow cytometry, fluorescence correlation spectroscopy, fluorescence microscopy, fluorescence polarization, fluorescence resonance energy transfer, and scanning confocal microscopy. Thus, the approach of fluorescent labeled GPCR ligands, including those for ARs, is a growing dynamic research field.
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Affiliation(s)
- Eszter Kozma
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892-0810 USA
| | - P Suresh Jayasekara
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892-0810 USA
| | - Lucia Squarcialupi
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892-0810 USA
| | - Silvia Paoletta
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892-0810 USA
| | - Stefano Moro
- Molecular Modeling Section (MMS), Dipartimento di Scienze del Farmaco, Università di Padova, via Marzolo 5, I-35131 Padova, Italy
| | - Stephanie Federico
- Dipartimento di Scienze Chimiche e Farmaceutiche, Università di Trieste, Piazzale Europa 1, I-34127 Trieste, Italy
| | - Giampiero Spalluto
- Dipartimento di Scienze Chimiche e Farmaceutiche, Università di Trieste, Piazzale Europa 1, I-34127 Trieste, Italy
| | - Kenneth A. Jacobson
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892-0810 USA
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Stoddart L, Vernall A, Denman J, Briddon S, Kellam B, Hill S. Fragment screening at adenosine-A(3) receptors in living cells using a fluorescence-based binding assay. CHEMISTRY & BIOLOGY 2012; 19:1105-15. [PMID: 22999879 PMCID: PMC3456874 DOI: 10.1016/j.chembiol.2012.07.014] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/26/2012] [Revised: 06/22/2012] [Accepted: 07/17/2012] [Indexed: 10/31/2022]
Abstract
G protein-coupled receptors (GPCRs) comprise the largest family of transmembrane proteins. For GPCR drug discovery, it is important that ligand affinity is determined in the correct cellular environment and preferably using an unmodified receptor. We developed a live cell high-content screening assay that uses a fluorescent antagonist, CA200645, to determine binding affinity constants of competing ligands at human adenosine-A(1) and -A(3) receptors. This method was validated as a tool to screen a library of low molecular weight fragments, and identified a hit with submicromolar binding affinity (K(D)). This fragment was structurally unrelated to substructures of known adenosine receptor antagonists and was optimized to show selectivity for the adenosine-A(3) receptor. This technology represents a significant advance that will allow the determination of ligand and fragment affinities at receptors in their native membrane environment.
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Affiliation(s)
- Leigh A. Stoddart
- Institute of Cell Signalling, School of Biomedical Science, Queen's Medical Centre, University of Nottingham, Nottingham NG7 2UH, UK
| | - Andrea J. Vernall
- School of Pharmacy, Centre for Biomolecular Sciences, University of Nottingham, Nottingham NG7 2RD, UK
| | - Jessica L. Denman
- Institute of Cell Signalling, School of Biomedical Science, Queen's Medical Centre, University of Nottingham, Nottingham NG7 2UH, UK
| | - Stephen J. Briddon
- Institute of Cell Signalling, School of Biomedical Science, Queen's Medical Centre, University of Nottingham, Nottingham NG7 2UH, UK
| | - Barrie Kellam
- School of Pharmacy, Centre for Biomolecular Sciences, University of Nottingham, Nottingham NG7 2RD, UK
| | - Stephen J. Hill
- Institute of Cell Signalling, School of Biomedical Science, Queen's Medical Centre, University of Nottingham, Nottingham NG7 2UH, UK
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Rose RH, Briddon SJ, Hill SJ. A novel fluorescent histamine H(1) receptor antagonist demonstrates the advantage of using fluorescence correlation spectroscopy to study the binding of lipophilic ligands. Br J Pharmacol 2012; 165:1789-1800. [PMID: 21880035 DOI: 10.1111/j.1476-5381.2011.01640.x] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
BACKGROUND AND PURPOSE Fluorescent ligands facilitate the study of ligand-receptor interactions at the level of single cells and individual receptors. Here, we describe a novel fluorescent histamine H(1) receptor antagonist (mepyramine-BODIPY630-650) and use it to monitor the membrane diffusion of the histamine H(1) receptor. EXPERIMENTAL APPROACH The human histamine H(1) receptor fused to yellow fluorescent protein (YFP) was transiently expressed in CHO-K1 cells. The time course of binding of mepyramine-BODIPY630-650 to the H(1) receptor was determined by confocal microscopy. Additionally, fluorescence correlation spectroscopy (FCS) was used to characterize the diffusion coefficient of the H(1) receptor in cell membranes both directly (YFP fluorescence) and in its antagonist-bound state (with mepyramine-BODIPY630-650). KEY RESULTS Mepyramine-BODIPY630-650 was a high-affinity antagonist at the histamine H(1) receptor. Specific membrane binding, in addition to significant intracellular uptake of the fluorescent ligand, was detected by confocal microscopy. However, FCS was able to quantify the receptor-specific binding in the membrane, as well as the diffusion coefficient of the antagonist-H(1) receptor-YFP complexes, which was significantly slower than when determined directly using YFP. FCS also detected specific binding of mepyramine-BODIPY630-650 to the endogenous H(1) receptor in HeLa cells. CONCLUSIONS AND IMPLICATIONS Mepyramine-BODIPY630-650 is a useful tool for localizing the H(1) receptor using confocal microscopy. However, its use in conjunction with FCS allows quantification of ligand binding at the membrane, as well as determining receptor diffusion in the absence of significant bleaching effects. Finally, these methods can be successfully extended to endogenously expressed untagged receptors in HeLa cells.
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Affiliation(s)
- Rachel H Rose
- Institute of Cell Signalling, School of Biomedical Sciences, University of Nottingham, Nottingham, UK
| | - Stephen J Briddon
- Institute of Cell Signalling, School of Biomedical Sciences, University of Nottingham, Nottingham, UK
| | - Stephen J Hill
- Institute of Cell Signalling, School of Biomedical Sciences, University of Nottingham, Nottingham, UK
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Kozma E, Kumar TS, Federico S, Phan K, Balasubramanian R, Gao ZG, Paoletta S, Moro S, Spalluto G, Jacobson KA. Novel fluorescent antagonist as a molecular probe in A(3) adenosine receptor binding assays using flow cytometry. Biochem Pharmacol 2012; 83:1552-61. [PMID: 22402302 PMCID: PMC3322254 DOI: 10.1016/j.bcp.2012.02.019] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2012] [Revised: 02/17/2012] [Accepted: 02/22/2012] [Indexed: 10/28/2022]
Abstract
The physiological role of the A(3) adenosine receptor (AR) was explored in cardiac ischaemia, inflammatory diseases and cancer. We report a new fluorophore-conjugated human (h) A(3)AR antagonist for application to cell-based assays in ligand discovery and for receptor imaging. Fluorescent pyrazolo[4,3-e][1,2,4]triazolo[1,5-c]pyrimidin-5-ylamine (pyrazolo-triazolo-pyrimidine, PTP) and triazolo[1,5-c]quinazolin-5-yl)amine (triazolo-quinazoline, TQ) AR antagonists were compared. A chain-extended and click-conjugated Alexa Fluor-488 TQ derivative (MRS5449) displayed a radioligand binding K(i) value of 6.4±2.5nM in hA(3)AR-expressing CHO cell membranes. MRS5449 antagonized hA(3)AR agonist-induced inhibition of cyclic AMP accumulation in a concentration-dependent manner (K(B)=4.8nM). Using flow cytometry (FCM), MRS5449 saturated hA(3)ARs with very high specific-to-nonspecific binding ratio with an equilibrium binding constant 5.15nM, comparable to the K(d) value of 6.65nM calculated from kinetic experiments. K(i) values of known AR antagonists in inhibition of MRS5449 binding in whole cell FCM were consistent with radioligand binding in membranes, but agonist binding was 5-20 fold weaker than obtained with agonist radioligand [(125)I]I-AB-MECA. Further binding analysis of MRS5549 suggested multiple agonist binding states of the A(3)AR. Molecular docking predicted binding modes of these fluorescent antagonists. Thus, MRS5449 is a useful tool for hA(3)AR characterization.
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Affiliation(s)
- Eszter Kozma
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892-0810 USA
| | - T. Santhosh Kumar
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892-0810 USA
| | - Stephanie Federico
- Dipartimento di Scienze Farmaceutiche, Università di Trieste, Piazzale Europa 1, I-34127 Trieste, Italy
| | - Khai Phan
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892-0810 USA
| | - Ramachandran Balasubramanian
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892-0810 USA
| | - Zhan-Guo Gao
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892-0810 USA
| | - Silvia Paoletta
- Molecular Modeling Section (MMS), Dipartimento di Scienze Farmaceutiche, Università di Padova, via Marzolo 5, I-35131 Padova, Italy
| | - Stefano Moro
- Molecular Modeling Section (MMS), Dipartimento di Scienze Farmaceutiche, Università di Padova, via Marzolo 5, I-35131 Padova, Italy
| | - Giampiero Spalluto
- Dipartimento di Scienze Farmaceutiche, Università di Trieste, Piazzale Europa 1, I-34127 Trieste, Italy
| | - Kenneth A. Jacobson
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892-0810 USA
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Kilpatrick LE, Briddon SJ, Holliday ND. Fluorescence correlation spectroscopy, combined with bimolecular fluorescence complementation, reveals the effects of β-arrestin complexes and endocytic targeting on the membrane mobility of neuropeptide Y receptors. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2012; 1823:1068-81. [PMID: 22487268 PMCID: PMC3793875 DOI: 10.1016/j.bbamcr.2012.03.002] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/07/2011] [Revised: 02/29/2012] [Accepted: 03/01/2012] [Indexed: 01/22/2023]
Abstract
Fluorescence correlation spectroscopy (FCS) and photon counting histogram (PCH) analysis are powerful ways to study mobility and stoichiometry of G protein coupled receptor complexes, within microdomains of single living cells. However, relating these properties to molecular mechanisms can be challenging. We investigated the influence of β-arrestin adaptors and endocytosis mechanisms on plasma membrane diffusion and particle brightness of GFP-tagged neuropeptide Y (NPY) receptors. A novel GFP-based bimolecular fluorescence complementation (BiFC) system also identified Y1 receptor-β-arrestin complexes. Diffusion co-efficients (D) for Y1 and Y2-GFP receptors in HEK293 cell plasma membranes were 2.22 and 2.15 × 10− 9 cm2 s− 1 respectively. At a concentration which promoted only Y1 receptor endocytosis, NPY treatment reduced Y1-GFP motility (D 1.48 × 10− 9 cm2 s− 1), but did not alter diffusion characteristics of the Y2-GFP receptor. Agonist induced changes in Y1 receptor motility were inhibited by mutations (6A) which prevented β-arrestin recruitment and internalisation; conversely they became apparent in a Y2 receptor mutant with increased β-arrestin affinity. NPY treatment also increased Y1 receptor-GFP particle brightness, changes which indicated receptor clustering, and which were abolished by the 6A mutation. The importance of β-arrestin recruitment for these effects was illustrated by reduced lateral mobility (D 1.20–1.33 × 10− 9 cm2 s− 1) of Y1 receptor-β-arrestin BiFC complexes. Thus NPY-induced changes in Y receptor motility and brightness reflect early events surrounding arrestin dependent endocytosis at the plasma membrane, results supported by a novel combined BiFC/FCS approach to detect the underlying receptor-β-arrestin signalling complex.
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Affiliation(s)
- Laura E Kilpatrick
- Cell Signaling Research Group, School of Biomedical Sciences, University of Nottingham, the Medical School, Queen's Medical Centre, Nottingham, UK
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Hill SJ, Williams C, May LT. Insights into GPCR pharmacology from the measurement of changes in intracellular cyclic AMP; advantages and pitfalls of differing methodologies. Br J Pharmacol 2011; 161:1266-75. [PMID: 21049583 DOI: 10.1111/j.1476-5381.2010.00779.x] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
It is clear that the G protein-coupled receptor family play a key role in the pharmaceutical industry, with a significant proportion of approved drugs targeting this protein class. While our growing understanding of the complexity of G protein-coupled receptor pharmacology is playing a key role in the future success of these endeavours, with allosteric mechanisms now well integrated into the industrial community and G protein-independent signalling mechanisms establishing themselves as novel phenomenon to be exploited, it is still possible to underestimate the complexity of G protein signal transduction mechanisms and the impact that inappropriate study of these mechanisms can have on data interpretation. In this manuscript we review different approaches to measuring the cAMP signal transduction pathway, with particular emphasis on key parameters influencing the data quality and biological relevance.
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Affiliation(s)
- Stephen J Hill
- Institute of Cell Signalling, School of Biomedical Sciences, Medical School, Queen's Medical Centre, Nottingham, UK.
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Baker JG, Adams LA, Salchow K, Mistry SN, Middleton RJ, Hill SJ, Kellam B. Synthesis and characterization of high-affinity 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene-labeled fluorescent ligands for human β-adrenoceptors. J Med Chem 2011; 54:6874-87. [PMID: 21870877 PMCID: PMC3188295 DOI: 10.1021/jm2008562] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
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The growing practice of exploiting noninvasive fluorescence-based techniques to study G protein-coupled receptor pharmacology at the single cell and single molecule level demands the availability of high-quality fluorescent ligands. To this end, this study evaluated a new series of red-emitting ligands for the human β-adrenoceptor family. Upon the basis of the orthosteric ligands propranolol, alprenolol, and pindolol, the synthesized linker-modified congeners were coupled to the commercially available fluorophore BODIPY 630/650-X. This yielded high-affinity β-adrenoceptor fluorescent ligands for both the propranolol and alprenolol derivatives; however, the pindolol-based products displayed lower affinity. A fluorescent diethylene glycol linked propranolol derivative (18a) had the highest affinity (log KD of −9.53 and −8.46 as an antagonist of functional β2- and β1-mediated responses, respectively). Imaging studies with this compound further confirmed that it can be employed to selectively label the human β2-adrenoceptor in single living cells, with receptor-associated binding prevented by preincubation with the nonfluorescent β2-selective antagonist 3-(isopropylamino)-1-[(7-methyl-4-indanyl)oxy]butan-2-ol (ICI 118551) (J. Cardiovasc. Pharmacol.1983, 5, 430–437.)
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Affiliation(s)
- Jillian G Baker
- School of Pharmacy, Centre for Biomolecular Sciences, University of Nottingham, University Park, Nottingham NG7 2RD, United Kingdom
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May LT, Bridge LJ, Stoddart LA, Briddon SJ, Hill SJ. Allosteric interactions across native adenosine-A3 receptor homodimers: quantification using single-cell ligand-binding kinetics. FASEB J 2011; 25:3465-76. [PMID: 21715680 PMCID: PMC3177574 DOI: 10.1096/fj.11-186296] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
A growing awareness indicates that many G-protein-coupled receptors (GPCRs) exist as homodimers, but the extent of the cooperativity across the dimer interface has been largely unexplored. Here, measurement of the dissociation kinetics of a fluorescent agonist (ABA-X-BY630) from the human A1 or A3 adenosine receptors expressed in CHO-K1 cells has provided evidence for highly cooperative interactions between protomers of the A3-receptor dimer in single living cells. In the absence of competitive ligands, the dissociation rate constants of ABA-X-BY630 from A1 and A3 receptors were 1.45 ± 0.05 and 0.57 ± 0.07 min−1, respectively. At the A3 receptor, this could be markedly increased by both orthosteric agonists and antagonists [15-, 9-, and 19-fold for xanthine amine congener (XAC), 5′-(N-ethyl carboxamido)adenosine (NECA), and adenosine, respectively] and reduced by coexpression of a nonbinding (N250A) A3-receptor mutant. The changes in ABA-X-BY630 dissociation were much lower at the A1 receptor (1.5-, 1.4-, and 1.5-fold). Analysis of the pEC50 values of XAC, NECA, and adenosine for the ABA-X-BY630-occupied A3-receptor dimer yielded values of 6.0 ± 0.1, 5.9 ± 0.1, and 5.2 ± 0.1, respectively. This study provides new insight into the spatial and temporal specificity of drug action that can be provided by allosteric modulation across a GPCR homodimeric interface.—May, L. T., Bridge, L. J., Stoddart, L. A., Briddon, S. J., Hill, S. J. Allosteric interactions across native adenosine-A3 receptor homodimers: quantification using single-cell ligand-binding kinetics.
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Affiliation(s)
- Lauren T May
- Institute of Cell Signalling, School of Biomedical Sciences, The University of Nottingham, Nottingham, UK, NG7 2UH
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Kaya Aİ, Uğur O, Altuntaş O, Sayar K, Onaran HO. Long and short distance movements of β(2)-adrenoceptor in cell membrane assessed by photoconvertible fluorescent protein dendra2-β(2)-adrenoceptor fusion. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2011; 1813:1511-24. [PMID: 21621562 DOI: 10.1016/j.bbamcr.2011.05.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2011] [Revised: 04/04/2011] [Accepted: 05/08/2011] [Indexed: 11/29/2022]
Abstract
Local movements of receptors in the plasma membrane have been extensively studied, as it is generally believed that the dynamics of membrane distribution of receptors regulate their functions. However, the properties of large-scale (>5μm) receptor movements in the membrane are relatively obscure. In the present study, we addressed the question as to whether the large-scale movement of receptor in the plasma membrane at the whole cell level can be explained quantitatively by its local diffusive properties. We used HEK 293 cells transfected with human β2-adrenoceptor fused to photoconvertible fluorescent protein dendra2 as a model system; and found that 1) functional integrity of the dendra2-tagged receptor remains apparently intact; 2) in a mesoscopic scale (~4μm), ~90% of the receptors are mobile on average, and receptor influx to, and out-flux from a membrane area can be symmetrically explained by a diffusion-like process with an effective diffusion coefficient of ~0.1μm(2)/s; 3) these mobility parameters are not affected by the activity state of the receptor (assessed by using constitutively active receptor mutants); 4) in the macroscopic scale (4-40μm), although a slowly diffusing fraction of receptors (with D<0.01μm(2)/s) is identifiable in some cases, the movement of the predominant fraction is perfectly explained by the same effective diffusion process observed in the mesoscopic scale, suggesting that the large scale structure of the cell membrane as felt by the receptor is apparently homogeneous in terms of its mesoscopic properties. We also showed that intracellular compartments and plasma membrane are kinetically connected even at steady-state.
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Affiliation(s)
- Ali İ Kaya
- Ankara University Faculty of Medicine, Molecular Biology and Technology Development Unit, 06100 Sıhhiye, Ankara, Turkey
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41
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Guidolin D, Ciruela F, Genedani S, Guescini M, Tortorella C, Albertin G, Fuxe K, Agnati LF. Bioinformatics and mathematical modelling in the study of receptor–receptor interactions and receptor oligomerization. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2011; 1808:1267-83. [DOI: 10.1016/j.bbamem.2010.09.022] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2010] [Revised: 08/31/2010] [Accepted: 09/26/2010] [Indexed: 10/19/2022]
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Müller CE, Jacobson KA. Recent developments in adenosine receptor ligands and their potential as novel drugs. BIOCHIMICA ET BIOPHYSICA ACTA 2011; 1808:1290-308. [PMID: 21185259 PMCID: PMC3437328 DOI: 10.1016/j.bbamem.2010.12.017] [Citation(s) in RCA: 332] [Impact Index Per Article: 25.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2010] [Revised: 12/14/2010] [Accepted: 12/15/2010] [Indexed: 01/16/2023]
Abstract
Medicinal chemical approaches have been applied to all four of the adenosine receptor (AR) subtypes (A(1), A(2A), A(2B), and A(3)) to create selective agonists and antagonists for each. The most recent class of selective AR ligands to be reported is the class of A(2B)AR agonists. The availability of these selective ligands has facilitated research on therapeutic applications of modulating the ARs and in some cases has provided clinical candidates. Prodrug approaches have been developed which improve the bioavailability of the drugs, reduce side-effects, and/or may lead to site-selective effects. The A(2A) agonist regadenoson (Lexiscan®), a diagnostic drug for myocardial perfusion imaging, is the first selective AR agonist to be approved. Other selective agonists and antagonists are or were undergoing clinical trials for a broad range of indications, including capadenoson and tecadenoson (A(1) agonists) for atrial fibrillation, or paroxysmal supraventricular tachycardia, respectively, apadenoson and binodenoson (A(2A) agonists) for myocardial perfusion imaging, preladenant (A(2A) antagonist) for the treatment of Parkinson's disease, and CF101 and CF102 (A(3) agonists) for inflammatory diseases and cancer, respectively.
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Briddon SJ, Kellam B, Hill SJ. Design and use of fluorescent ligands to study ligand-receptor interactions in single living cells. Methods Mol Biol 2011; 746:211-236. [PMID: 21607859 DOI: 10.1007/978-1-61779-126-0_11] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The interaction of ligands with G protein-coupled receptors (GPCRs) has been traditionally studied using radiolabelled variants of receptor ligands. More recently, increased knowledge about the way in which GPCRs exist in a highly organised membrane environment has led to an interest in investigating receptor-ligand interactions in single cells. In addition, substantial improvements in imaging technology and an increase in the expense of radioactive waste disposal have resulted in an expansion in the use of fluorescent technologies. One major requirement for these methods is a suitable fluorescent ligand for the receptor of interest. The design of fluorescent ligands for GPCRs is complex, and has to take into account their pharmacological, photophysical, and also physicochemical properties. Here, we describe some basic considerations in the design of fluorescent GPCR ligands, including choice of pharmacological template, linker, and fluorophore. In addition, we describe basic protocols for determining the photophysical properties of the ligand and determining the cellular localisation of their interaction with the target receptors. Finally, we provide a basic protocol for using fluorescent GPCR ligands to quantify the number and diffusion of receptor-ligand complexes in small areas of the cell membrane.
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Affiliation(s)
- Stephen J Briddon
- Institute of Cell Signalling, School of Biomedical Sciences, University of Nottingham, Nottingham, UK.
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44
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Lasley RD. Adenosine receptors and membrane microdomains. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2010; 1808:1284-9. [PMID: 20888790 DOI: 10.1016/j.bbamem.2010.09.019] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2010] [Revised: 09/20/2010] [Accepted: 09/25/2010] [Indexed: 11/16/2022]
Abstract
Adenosine receptors are a member of the large family of seven transmembrane spanning G protein coupled receptors. The four adenosine receptor subtypes-A(1), A(2a), A(2b), A(3)-exert their effects via the activation of one or more heterotrimeric G proteins resulting in the modulation of intracellular signaling. Numerous studies over the past decade have documented the complexity of G protein coupled receptor signaling at the level of protein-protein interactions as well as through signaling cross talk. With respect to adenosine receptors, the activation of one receptor subtype can have profound direct effects in one cell type but little or no effect in other cells. There is significant evidence that the compartmentation of subcellular signaling plays a physiological role in the fidelity of G protein coupled receptor signaling. This compartmentation is evident at the level of the plasma membrane in the form of membrane microdomains such as caveolae and lipid rafts. This review will summarize and critically assess our current understanding of the role of membrane microdomains in regulating adenosine receptor signaling.
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Affiliation(s)
- Robert D Lasley
- Department of Physiology, Wayne State University School of Medicine, Detroit, MI, USA.
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May LT, Self TJ, Briddon SJ, Hill SJ. The effect of allosteric modulators on the kinetics of agonist-G protein-coupled receptor interactions in single living cells. Mol Pharmacol 2010; 78:511-23. [PMID: 20571079 DOI: 10.1124/mol.110.064493] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Allosteric binding sites on adenosine -A(1) and -A(3) receptors represent attractive therapeutic targets for amplifying, in a spatially and temporally selective manner, the tissue protective actions of endogenous adenosine. This study has directly quantified the kinetics of agonist/G protein-coupled receptor interactions at the single-cell level, reflecting the physiological situation in which intracellular signaling proteins can exert major allosteric effects on agonist-receptor interactions. The association and dissociation rate constants at both A(1) and A(3) receptors, and therefore the affinity of the fluorescent adenosine derivative ABA-X-BY630 (structure appears in J Med Chem 50:782-793, 2007), were concentration-independent. The equilibrium dissociation constants of ABA-X-BY630 at A(1) and A(3) receptors were approximately 50 and 10 nM, respectively, suggesting that, even in live cells, low agonist concentrations predominantly detect high-affinity receptor states. At A(1) receptors, the dissociation of ABA-X-BY630 (30 nM) was significantly faster in the absence (k(off) = 1.95 +/- 0.09 min(-1)) compared with the presence of the allosteric enhancer (2-amino-4,5-dimethyl-3-thienyl)(3-(trifluoromethyl)phenyl)-methanone (PD81,723; 10 microM; k(off) = 0.80 +/- 0.03 min(-1)) and allosteric inhibitor 4-methoxy-N-(7-methyl-3-(2-pyridinyl)-1-isoquinolinyl)benzamide (VUF5455; 1 microM; k(off) = 1.48 +/- 0.16 min(-1)). In contrast, ABA-X-BY630 dissociation from A(3) receptors was significantly slower in the absence (k(off) = 0.78 +/- 0.18 min(-1)) than in the presence of the allosteric inhibitors VUF5455 (1 microM; k(off) = 3.15 +/- 0.12 min(-1)) and PD81,723 (10 microM; k(off) = 2.46 +/- 0.18 min(-1)). An allosteric mechanism of action has previously not been identified for PD81,723 at the A(3) receptor or VUF5455 at the A(1) receptor. Furthermore, the marked enhancement in fluorescent agonist dissociation by VUF5455 in living cells contrasts previous observations from broken cell preparations and emphasizes the need to study the allosteric regulation of agonist binding in living cells.
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Affiliation(s)
- Lauren T May
- The Institute of Cell Signalling, School of Biomedical Sciences, the University of Nottingham, Nottingham, United Kingdom
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46
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Baker JG, Middleton R, Adams L, May LT, Briddon SJ, Kellam B, Hill SJ. Influence of fluorophore and linker composition on the pharmacology of fluorescent adenosine A1 receptor ligands. Br J Pharmacol 2010; 159:772-86. [PMID: 20105183 PMCID: PMC2829203 DOI: 10.1111/j.1476-5381.2009.00488.x] [Citation(s) in RCA: 74] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Background and purpose: The introduction of fluorescence-based techniques, and in particular the development of fluorescent ligands, has allowed the study of G protein-coupled receptor pharmacology at the single cell and single molecule level. This study evaluated how the physicochemical nature of the linker and the fluorophore affected the pharmacological properties of fluorescent agonists and antagonists. Experimental approach: Chinese hamster ovary cells stably expressing the human adenosine A1 receptor and a cyclic 3′,5′ adenosine monophosphate response element-secreted placental alkaline phosphatase (CRE-SPAP) reporter gene, together with whole cell [3H]-8-cyclopentyl-1,3-dipropylxanthine (DPCPX) radioligand binding, were used to evaluate the pharmacological properties of a range of fluorescent ligands based on the antagonist xanthine amine congener (XAC) and the agonist 5′ (N-ethylcarboxamido) adenosine (NECA). Key results: Derivatives of NECA and XAC with different fluorophores, but equivalent linker length, showed significant differences in their binding properties to the adenosine A1 receptor. The BODIPY 630/650 derivatives had the highest affinity. Linker length also affected the pharmacological properties, depending on the fluorophore used. Particularly in fluorescent agonists, higher agonist potency could be achieved with large or small linkers for dansyl and BODIPY 630/650 derivatives, respectively. Conclusions and implications: The pharmacology of a fluorescent ligand was critically influenced by both the fluorophore and the associated linker. Furthermore, our data strongly suggest that the physicochemical properties of the fluorophore/linker pairing determine where in the environment of the target receptor the fluorophore is placed, and this, together with the environmental sensitivity of the resulting fluorescence, may finally decide its utility as a fluorescent probe. This article is part of a themed section on Imaging in Pharmacology. To view the editorial for this themed section visit http://dx.doi.org/10.1111/j.1476-5381.2010.00685.x
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Affiliation(s)
- Jillian G Baker
- Institute of Cell Signalling, School of Biomedical Sciences, Medical School, University of Nottingham, Queen's Medical Centre, Nottingham, UK
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May LT, Briddon SJ, Hill SJ. Antagonist selective modulation of adenosine A1 and A3 receptor pharmacology by the food dye Brilliant Black BN: evidence for allosteric interactions. Mol Pharmacol 2010; 77:678-86. [PMID: 20086038 DOI: 10.1124/mol.109.063065] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Allosteric binding sites on the adenosine receptor family represent potential therapeutic targets for a number of conditions involving metabolic stress. This study has identified Brilliant Black BN as a novel allosteric modulator of the adenosine A(1) and A(3) receptors. In addition to being a food dye and pharmaceutical excipient, Brilliant Black BN is commonly used within calcium mobilization assays to quench extracellular fluorescence. Brilliant Black BN (5-500 microM) had no significant effect on the calcium mobilization stimulated by the nonselective adenosine receptor agonist 5'-(N-ethylcarboxamido)adenosine in Chinese hamster ovary cells stably transfected with the human adenosine A(1) or A(3) receptor. Likewise, calcium mobilization and radioligand binding assays found that Brilliant Black BN (5-500 microM) did not significantly influence the antagonism mediated by 8-cyclopentyl-1,3-dipropylxanthine (100 nM) at the A(1) receptor. In contrast, the affinity of N-[9-chloro-2-(2-furanyl)[1,2,4]-triazolo[1,5-c]quinazolin-5-yl]benzene acetamide (MRS1220) at the A(3) receptor and xanthine amine congener (XAC) and XAC-X-BY630 at the A(1) and A(3) receptors was significantly decreased in the presence of 500 muM Brilliant Black BN. A reduction in XAC potency at the A(1) and A(3) receptor was achieved within 1 min of Brilliant Black BN addition, despite receptors having been pre-equilibrated with antagonist. Dissociation kinetics of the fluorescent XAC derivative, XAC-X-BY630, revealed that the decrease in affinity is probably due to a significant increase in dissociation rate of the antagonist in the presence of Brilliant Black BN. Taken together, these results suggest that Brilliant Black BN can act allosterically to modify ligand affinity at A(1) and A(3) receptors.
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Affiliation(s)
- L T May
- Institute of Cell Signaling, The University of Nottingham Medical School, Queen's Medical Centre, Nottingham NG7 2UH, UK
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48
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García-Sáez AJ, Carrer DC, Schwille P. Fluorescence correlation spectroscopy for the study of membrane dynamics and organization in giant unilamellar vesicles. Methods Mol Biol 2010; 606:493-508. [PMID: 20013417 DOI: 10.1007/978-1-60761-447-0_33] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Fluorescence correlation spectroscopy (FCS) is a powerful technique to study the lateral organization of membranes. It measures fluorescence intensity fluctuations in the single molecule regime and allows the determination of diffusion coefficients. When applied to lipid membranes, their fluidity and lipid phase can be estimated from the diffusion rates of fluorescent particles partitioned to the membrane. Here, we describe the theoretical basis of FCS and discuss the z-scan approach for measurements on lipid membranes. We also list the materials necessary for a FCS experiment on giant unilamellar vesicles (GUVs). Finally, we present simple protocols for the preparation of GUVs and the acquisition and analysis of FCS data on the vesicles, so that diffusion coefficients of fluorescent probes within lipid membranes can be estimated.
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Tosh DK, Chinn M, Ivanov AA, Klutz AM, Gao ZG, Jacobson KA. Functionalized congeners of A3 adenosine receptor-selective nucleosides containing a bicyclo[3.1.0]hexane ring system. J Med Chem 2009; 52:7580-92. [PMID: 19499950 PMCID: PMC3109436 DOI: 10.1021/jm900426g] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
(N)-Methanocarba nucleosides containing bicyclo[3.1.0]hexane replacement of the ribose ring previously demonstrated selectivity as A(3) adenosine receptor (AR) agonists (5'-uronamides) or antagonists (5'-truncated). Here, these two series were modified in parallel at the adenine C2 position. N(6)-3-Chlorobenzyl-5'-N-methyluronamides derivatives with functionalized 2-alkynyl chains of varying length terminating in a reactive carboxylate, ester, or amine group were full, potent human A(3)AR agonists. Flexibility of chain substitution allowed the conjugation with a fluorescent cyanine dye (Cy5) and biotin, resulting in binding K(i) values of 17 and 36 nM, respectively. The distal end of the chain was predicted by homology modeling to bind at the A(3)AR extracellular regions. Corresponding l-nucleosides were nearly inactive in AR binding. In the 5'-truncated nucleoside series, 2-Cl analogues were more potent at A(3)AR than 2-H and 2-F, functional efficacy in adenylate cyclase inhibition varied, and introduction of a 2-alkynyl chain greatly reduced affinity. SAR parallels between the two series lost stringency at distal positions. The most potent and selective novel compounds were amine congener 15 (K(i) = 2.1 nM) and truncated partial agonist 22 (K(i) = 4.9 nM).
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Affiliation(s)
- Dilip K. Tosh
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892
| | - Moshe Chinn
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892
| | - Andrei A. Ivanov
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892
- Department of Biochemistry, Emory University School of Medicine, 1510 Clifton Road, Rollins Research Center, Atlanta, Georgia 30322
| | - Athena M. Klutz
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892
| | - Zhan-Guo Gao
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892
| | - Kenneth A. Jacobson
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892
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50
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Das A, Zhou Y, Ivanov AA, Carter RL, Harden TK, Jacobson KA. Enhanced potency of nucleotide-dendrimer conjugates as agonists of the P2Y14 receptor: multivalent effect in G protein-coupled receptor recognition. Bioconjug Chem 2009; 20:1650-9. [PMID: 19572637 DOI: 10.1021/bc900206g] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The P2Y(14) receptor is a G protein-coupled receptor activated by uridine-5'-diphosphoglucose and other nucleotide sugars that modulates immune function. Covalent conjugation of P2Y(14) receptor agonists to PAMAM (polyamidoamine) dendrimers enhanced pharmacological activity. Uridine-5'-diphosphoglucuronic acid (UDPGA) and its ethylenediamine adduct were suitable functionalized congeners for coupling to several generations (G2.5-6) of dendrimers (both terminal carboxy and amino). Prosthetic groups, including biotin for avidin complexation, a chelating group for metal complexation (and eventual magnetic resonance imaging), and a fluorescent moiety, also were attached with the eventual goals of molecular detection and characterization of the P2Y(14) receptor. The activities of conjugates were assayed in HEK293 cells stably expressing the human P2Y(14) receptor. A G3 PAMAM conjugate containing 20 bound nucleotide moieties (UDPGA) was 100-fold more potent (EC(50) 2.4 nM) than the native agonist uridine-5'-diphosphoglucose. A molecular model of this conjugate docked in the human P2Y(14) receptor showed that the nucleotide-substituted branches could extend far beyond the dimensions of the receptor and be available for multivalent docking to receptor aggregates. Larger dendrimer carriers and greater loading favored higher potency. A similar conjugate of G6 with 147 out of 256 amino groups substituted with UDPGA displayed an EC(50) value of 0.8 nM. Thus, biological activity was either retained or dramatically enhanced in the multivalent dendrimer conjugates in comparison with monomeric P2Y(14) receptor agonists, depending on size, degree of substitution, terminal functionality, and attached prosthetic groups.
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Affiliation(s)
- Arijit Das
- Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA
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