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Casella B, Farmer JP, Nesheva DN, Williams HEL, Charlton SJ, Holliday ND, Laughton CA, Mistry SN. Design, Synthesis, and Application of Fluorescent Ligands Targeting the Intracellular Allosteric Binding Site of the CXC Chemokine Receptor 2. J Med Chem 2023; 66:12911-12930. [PMID: 37523859 PMCID: PMC10544029 DOI: 10.1021/acs.jmedchem.3c00849] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2023] [Indexed: 08/02/2023]
Abstract
The inhibition of CXC chemokine receptor 2 (CXCR2), a key inflammatory mediator, is a potential strategy in the treatment of several pulmonary diseases and cancers. The complexity of endogenous chemokine interaction with the orthosteric binding site has led to the development of CXCR2 negative allosteric modulators (NAMs) targeting an intracellular pocket near the G protein binding site. Our understanding of NAM binding and mode of action has been limited by the availability of suitable tracer ligands for competition studies, allowing direct ligand binding measurements. Here, we report the rational design, synthesis, and pharmacological evaluation of a series of fluorescent NAMs, based on navarixin (2), which display high affinity and preferential binding for CXCR2 over CXCR1. We demonstrate their application in fluorescence imaging and NanoBRET binding assays, in whole cells or membranes, capable of kinetic and equilibrium analysis of NAM binding, providing a platform to screen for alternative chemophores targeting these receptors.
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Affiliation(s)
- Bianca
Maria Casella
- Division
of Biomolecular Sciences and Medicinal Chemistry, School of Pharmacy, University of Nottingham Biodiscovery Institute, Nottingham NG7 2RD, UK
| | - James P. Farmer
- Division
of Physiology, Pharmacology & Neuroscience, Medical School, School
of Life Sciences, University of Nottingham, Nottingham NG7 2UH, UK
| | - Desislava N. Nesheva
- Division
of Physiology, Pharmacology & Neuroscience, Medical School, School
of Life Sciences, University of Nottingham, Nottingham NG7 2UH, UK
| | - Huw E. L. Williams
- School
of Chemistry, University of Nottingham Biodiscovery
Institute, Nottingham NG7 2RD, UK
| | - Steven J. Charlton
- Division
of Physiology, Pharmacology & Neuroscience, Medical School, School
of Life Sciences, University of Nottingham, Nottingham NG7 2UH, UK
- OMass
Therapeutics Ltd., Oxford OX4 2GX, UK
| | - Nicholas D. Holliday
- Division
of Physiology, Pharmacology & Neuroscience, Medical School, School
of Life Sciences, University of Nottingham, Nottingham NG7 2UH, UK
- Excellerate
Bioscience Ltd., Biocity, University of
Nottingham, Nottingham NG1 1GF, UK
| | - Charles A. Laughton
- Division
of Biomolecular Sciences and Medicinal Chemistry, School of Pharmacy, University of Nottingham Biodiscovery Institute, Nottingham NG7 2RD, UK
| | - Shailesh N. Mistry
- Division
of Biomolecular Sciences and Medicinal Chemistry, School of Pharmacy, University of Nottingham Biodiscovery Institute, Nottingham NG7 2RD, UK
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2
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Mani I, Singh V. An overview of receptor endocytosis and signaling. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2023; 194:1-18. [PMID: 36631188 DOI: 10.1016/bs.pmbts.2022.06.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Endocytosis is a cellular process which mediates receptor internalization, nutrient uptake, and the regulation of cell signaling. Microorganisms (many bacteria and viruses) and toxins also use the same process and enter the cells. Generally, endocytosis is considered in the three forms such as phagocytosis (cell eating), pinocytosis (cell drinking), and highly selective receptor-mediated endocytosis (clathrin-dependent and independent). Several endocytic routes exist in an analogous, achieving diverse functions. Most studies on endocytosis have used transformed cells in culture. To visualize the receptor internalization, trafficking, and signaling in subcellular organelles, a green fluorescent protein-tagged receptor has been utilized. It also helps to visualize the endocytosis effects in live-cell imaging. Confocal laser microscopy increases our understanding of receptor endocytosis and signaling. Site-directed mutagenesis studies demonstrated that many short-sequence motifs of the cytoplasmic domain of receptors significantly play a vital role in receptor internalization, subcellular trafficking, and signaling. However, other factors also regulate receptor internalization through clathrin-coated vesicles. Receptor endocytosis can occur through clathrin-dependent and clathrin-independent pathways. This chapter briefly discusses the internalization, trafficking, and signaling of various receptors in normal conditions. In addition, it also highlights the malfunction of the receptor in disease conditions.
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Affiliation(s)
- Indra Mani
- Department of Microbiology, Gargi College, University of Delhi, New Delhi, India.
| | - Vijai Singh
- Department of Biosciences, School of Science, Indrashil University, Rajpur, Mehsana, Gujarat, India
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3
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Pandita P, Bhalla R, Saini A, Mani I. Emerging tools for studying receptor endocytosis and signaling. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2023; 194:19-48. [PMID: 36631193 DOI: 10.1016/bs.pmbts.2022.10.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Ligands, agonists, or antagonists use receptor-mediated endocytosis (RME) to reach their intracellular targets. After the internalization of ligand-receptor complexes, it traffics through different subcellular organelles such as early endosome, recycling endosome, lysosome, etc. Further, after the ligand binding to the receptor, different second messengers are generated, such as cGMP, cAMP, IP3, etc. Several methods have been used, such as radioligand binding assay, western blotting, co-immunoprecipitation (co-IP), qRT-PCR, immunofluorescence and confocal microscopy, microRNA/siRNA, and bioassays to understand the various events, such as internalization, subcellular trafficking, signaling, metabolic degradation, etc. This chapter briefly discusses the key principles and methods used to study internalization, subcellular trafficking, signaling, and metabolic degradation of numerous receptors.
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Affiliation(s)
- Pratiksha Pandita
- Faculty of Medicine, Department of Infectious Disease, Imperial College London, London, United Kingdom
| | - Rhea Bhalla
- ICMR-National Institute of Virology, Pune, Maharashtra, India
| | - Ashok Saini
- Department of Microbiology, Institute of Home Economics, University of Delhi, New Delhi, India
| | - Indra Mani
- Department of Microbiology, Gargi College, University of Delhi, New Delhi, India.
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4
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Ragini, Sakshi, Saini A, Mani I. Endocytosis and signaling of 5-HT1A receptor. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2023; 196:113-123. [PMID: 36813354 DOI: 10.1016/bs.pmbts.2022.11.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The neurotransmitter serotonin (also known as 5-hydroxytryptamine, 5-HT) regulates many important physiological as well as pathological functions in the body like psychoemotional, sensation, blood circulation, food intake, autonomic, memory, sleep, pain, etc. 5-HT binds to its receptor 5-HT1A to initiate GTP exchange at the Gi/o protein, which activates the receptor G protein complex. G protein subunits attach to different effectors and generate various responses, such as inhibition of adenyl cyclase enzyme and regulates the opening of Ca++ and K+ ion channels. Activated signalling cascades activate protein kinase C (PKC) (a second messenger), which further induces the detachment of Gβγ-dependent receptor signaling and leads to 5-HT1A internalization. After internalization, 5-HT1A receptor attaches to the Ras-ERK1/2 pathway. The receptor further trafficks to the lysosome for degradation. Receptor skips the trafficking to the lysosomal compartments and undergoes dephosphorylation. Dephosphorylated receptors now recycled back to the cell membrane. In this chapter, we have discussed the internalization, trafficking and signaling of the 5-HT1A receptor.
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Affiliation(s)
- Ragini
- Department of Biotechnology, Regional Centre for Biotechnology, Faridabad, Haryana, India
| | - Sakshi
- Department of Biotechnology, Regional Centre for Biotechnology, Faridabad, Haryana, India
| | - Ashok Saini
- Department of Microbiology, Institute of Home Economics, University of Delhi, New Delhi, India
| | - Indra Mani
- Department of Microbiology, Gargi College, University of Delhi, New Delhi, India.
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5
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Nielsen CDT, Dhasmana D, Floresta G, Wohland T, Cilibrizzi A. Illuminating the Path to Target GPCR Structures and Functions. Biochemistry 2020; 59:3783-3795. [PMID: 32956586 DOI: 10.1021/acs.biochem.0c00606] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
G-Protein-coupled receptors (GPCRs) are ubiquitous within eukaryotes, responsible for a wide array of physiological and pathological processes. Indeed, the fact that they are the most drugged target in the human genome is indicative of their importance. Despite the clear interest in GPCRs, most information regarding their activity has been so far obtained by analyzing the response from a "bulk medium". As such, this Perspective summarizes some of the common methods for this indirect observation. Nonetheless, by inspecting approaches applying super-resolution imaging, we argue that imaging is perfectly situated to obtain more detailed structural and spatial information, assisting in the development of new GPCR-targeted drugs and clinical strategies. The benefits of direct optical visualization of GPCRs are analyzed in the context of potential future directions in the field.
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Affiliation(s)
- Christian D-T Nielsen
- Imperial College London, White City Campus, Molecular Sciences Research Hub, 80 Wood Lane, London W12 0BZ, U.K
| | - Divya Dhasmana
- Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, Singapore 117543
| | - Giuseppe Floresta
- Institute of Pharmaceutical Science, King's College London, London SE1 9NH, U.K
| | - Thorsten Wohland
- Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, Singapore 117543.,Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543
| | - Agostino Cilibrizzi
- Institute of Pharmaceutical Science, King's College London, London SE1 9NH, U.K
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6
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Koo CZ, Harrison N, Noy PJ, Szyroka J, Matthews AL, Hsia HE, Müller SA, Tüshaus J, Goulding J, Willis K, Apicella C, Cragoe B, Davis E, Keles M, Malinova A, McFarlane TA, Morrison PR, Nguyen HTH, Sykes MC, Ahmed H, Di Maio A, Seipold L, Saftig P, Cull E, Pliotas C, Rubinstein E, Poulter NS, Briddon SJ, Holliday ND, Lichtenthaler SF, Tomlinson MG. The tetraspanin Tspan15 is an essential subunit of an ADAM10 scissor complex. J Biol Chem 2020; 295:12822-12839. [PMID: 32111735 PMCID: PMC7476718 DOI: 10.1074/jbc.ra120.012601] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2020] [Revised: 02/14/2020] [Indexed: 12/13/2022] Open
Abstract
A disintegrin and metalloprotease 10 (ADAM10) is a transmembrane protein essential for embryonic development, and its dysregulation underlies disorders such as cancer, Alzheimer's disease, and inflammation. ADAM10 is a "molecular scissor" that proteolytically cleaves the extracellular region from >100 substrates, including Notch, amyloid precursor protein, cadherins, growth factors, and chemokines. ADAM10 has been recently proposed to function as six distinct scissors with different substrates, depending on its association with one of six regulatory tetraspanins, termed TspanC8s. However, it remains unclear to what degree ADAM10 function critically depends on a TspanC8 partner, and a lack of monoclonal antibodies specific for most TspanC8s has hindered investigation of this question. To address this knowledge gap, here we designed an immunogen to generate the first monoclonal antibodies targeting Tspan15, a model TspanC8. The immunogen was created in an ADAM10-knockout mouse cell line stably overexpressing human Tspan15, because we hypothesized that expression in this cell line would expose epitopes that are normally blocked by ADAM10. Following immunization of mice, this immunogen strategy generated four Tspan15 antibodies. Using these antibodies, we show that endogenous Tspan15 and ADAM10 co-localize on the cell surface, that ADAM10 is the principal Tspan15-interacting protein, that endogenous Tspan15 expression requires ADAM10 in cell lines and primary cells, and that a synthetic ADAM10/Tspan15 fusion protein is a functional scissor. Furthermore, two of the four antibodies impaired ADAM10/Tspan15 activity. These findings suggest that Tspan15 directly interacts with ADAM10 in a functional scissor complex.
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Affiliation(s)
- Chek Ziu Koo
- School of Biosciences, University of Birmingham, Birmingham B15 2TT, United Kingdom
- Centre of Membrane Proteins and Receptors (COMPARE), Universities of Birmingham and Nottingham, Midlands B15 2TT, United Kingdom
| | - Neale Harrison
- School of Biosciences, University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - Peter J Noy
- School of Biosciences, University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - Justyna Szyroka
- School of Biosciences, University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - Alexandra L Matthews
- School of Biosciences, University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - Hung-En Hsia
- German Center for Neurodegenerative Diseases (DZNE) Munich, Neuroproteomics, Klinikum rechts der Isar, Technical University Munich and Munich Cluster for Systems Neurology (SyNergy), 81377 Munich, Germany
| | - Stephan A Müller
- German Center for Neurodegenerative Diseases (DZNE) Munich, Neuroproteomics, Klinikum rechts der Isar, Technical University Munich and Munich Cluster for Systems Neurology (SyNergy), 81377 Munich, Germany
| | - Johanna Tüshaus
- German Center for Neurodegenerative Diseases (DZNE) Munich, Neuroproteomics, Klinikum rechts der Isar, Technical University Munich and Munich Cluster for Systems Neurology (SyNergy), 81377 Munich, Germany
| | - Joelle Goulding
- Centre of Membrane Proteins and Receptors (COMPARE), Universities of Birmingham and Nottingham, Midlands B15 2TT, United Kingdom
- Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Nottingham NG7 2UH, United Kingdom
| | - Katie Willis
- School of Biosciences, University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - Clara Apicella
- School of Biosciences, University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - Bethany Cragoe
- School of Biosciences, University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - Edward Davis
- School of Biosciences, University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - Murat Keles
- School of Biosciences, University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - Antonia Malinova
- School of Biosciences, University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - Thomas A McFarlane
- School of Biosciences, University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - Philip R Morrison
- School of Biosciences, University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - Hanh T H Nguyen
- School of Biosciences, University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - Michael C Sykes
- School of Biosciences, University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - Haroon Ahmed
- School of Biosciences, University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - Alessandro Di Maio
- School of Biosciences, University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - Lisa Seipold
- Institute of Biochemistry, Christian Albrechts University Kiel, 24118 Kiel, Germany
| | - Paul Saftig
- Institute of Biochemistry, Christian Albrechts University Kiel, 24118 Kiel, Germany
| | - Eleanor Cull
- School of Biosciences, University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - Christos Pliotas
- School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Eric Rubinstein
- Sorbonne Université, INSERM, CNRS, Centre d'Immunologie et des Maladies Infectieuses, CIMI-Paris, Paris 75013, France
| | - Natalie S Poulter
- Centre of Membrane Proteins and Receptors (COMPARE), Universities of Birmingham and Nottingham, Midlands B15 2TT, United Kingdom
- Institute of Cardiovascular Sciences, University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - Stephen J Briddon
- Centre of Membrane Proteins and Receptors (COMPARE), Universities of Birmingham and Nottingham, Midlands B15 2TT, United Kingdom
- Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Nottingham NG7 2UH, United Kingdom
| | - Nicholas D Holliday
- Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Nottingham NG7 2UH, United Kingdom
| | - Stefan F Lichtenthaler
- German Center for Neurodegenerative Diseases (DZNE) Munich, Neuroproteomics, Klinikum rechts der Isar, Technical University Munich and Munich Cluster for Systems Neurology (SyNergy), 81377 Munich, Germany
| | - Michael G Tomlinson
- School of Biosciences, University of Birmingham, Birmingham B15 2TT, United Kingdom
- Centre of Membrane Proteins and Receptors (COMPARE), Universities of Birmingham and Nottingham, Midlands B15 2TT, United Kingdom
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7
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Grime RL, Goulding J, Uddin R, Stoddart LA, Hill SJ, Poyner DR, Briddon SJ, Wheatley M. Single molecule binding of a ligand to a G-protein-coupled receptor in real time using fluorescence correlation spectroscopy, rendered possible by nano-encapsulation in styrene maleic acid lipid particles. NANOSCALE 2020; 12:11518-11525. [PMID: 32428052 DOI: 10.1039/d0nr01060j] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
The fundamental importance of membrane proteins in cellular processes has driven a marked increase in the use of membrane mimetic approaches for studying and exploiting these proteins. Nano-encapsulation strategies which preserve the native lipid bilayer environment are particularly attractive. Consequently, the use of poly(styrene co-maleic acid) (SMA) has been widely adopted to solubilise proteins directly from cell membranes by spontaneously forming "SMA Lipid Particles" (SMALPs). G-protein-coupled receptors (GPCRs) are ubiquitous "chemical switches", are central to cell signalling throughout the evolutionary tree, form the largest family of membrane proteins in humans and are a major drug discovery target. GPCR-SMALPs that retain binding capability would be a versatile platform for a wide range of down-stream applications. Here, using the adenosine A2A receptor (A2AR) as an archetypical GPCR, we show for the first time the utility of fluorescence correlation spectroscopy (FCS) to characterise the binding capability of GPCRs following nano-encapsulation. Unbound fluorescent ligand CA200645 exhibited a monophasic autocorrelation curve (dwell time, τD = 68 ± 2 μs; diffusion coefficient, D = 287 ± 15 μm2 s-1). In the presence of A2AR-SMALP, bound ligand was also evident (τD = 625 ± 23 μs; D = 30 ± 4 μm2 s-1). Using a non-receptor control (ZipA-SMALP) plus competition binding confirmed that this slower component represented binding to the encapsulated A2AR. Consequently, the combination of GPCR-SMALP and FCS is an effective platform for the quantitative real-time characterisation of nano-encapsulated receptors, with single molecule sensitivity, that will have widespread utility for future exploitation of GPCR-SMALPs in general.
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Affiliation(s)
- Rachael L Grime
- School of Biosciences, University of Birmingham, Birmingham, B15 2TT, UK and Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham and University of Nottingham, Midlands, UK
| | - Joelle Goulding
- Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham and University of Nottingham, Midlands, UK and Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Nottingham, NG7 2UH, UK
| | - Romez Uddin
- Life and Health Sciences, Aston University, Birmingham B4 7ET, UK
| | - Leigh A Stoddart
- Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham and University of Nottingham, Midlands, UK and Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Nottingham, NG7 2UH, UK
| | - Stephen J Hill
- Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham and University of Nottingham, Midlands, UK and Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Nottingham, NG7 2UH, UK
| | - David R Poyner
- Life and Health Sciences, Aston University, Birmingham B4 7ET, UK
| | - Stephen J Briddon
- Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham and University of Nottingham, Midlands, UK and Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Nottingham, NG7 2UH, UK
| | - Mark Wheatley
- Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham and University of Nottingham, Midlands, UK and Centre for Sport, Exercise and Life Sciences, Faculty of Health and Life Sciences, Alison Gingell Building, Coventry University, Coventry, CV1 2DS, UK.
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8
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Richardson RR, Groenen M, Liu M, Mountford SJ, Briddon SJ, Holliday ND, Thompson PE. Heterodimeric Analogues of the Potent Y1R Antagonist 1229U91, Lacking One of the Pharmacophoric C-Terminal Structures, Retain Potent Y1R Affinity and Show Improved Selectivity over Y4R. J Med Chem 2020; 63:5274-5286. [PMID: 32364733 DOI: 10.1021/acs.jmedchem.0c00027] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The cyclic dimeric peptide 1229U91 (GR231118) has an unusual structure and displays potent, insurmountable antagonism of the Y1 receptor. To probe the structural basis for this activity, we have prepared ring size variants and heterodimeric compounds, identifying the specific residues underpinning the mechanism of 1229U91 binding. The homodimeric structure was shown to be dispensible, with analogues lacking key pharmacophoric residues in one dimer arm retaining high antagonist affinity. Compounds 11d-h also showed enhanced Y1R selectivity over Y4R compared to 1229U91.
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Affiliation(s)
- Rachel R Richardson
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, 381 Royal Parade, Parkville, Victoria 3052, Australia.,Institute of Cell Signalling, School of Biomedical Sciences, Queen's Medical Centre, University of Nottingham, Nottingham NG7 2UH, U.K
| | - Marleen Groenen
- Institute of Cell Signalling, School of Biomedical Sciences, Queen's Medical Centre, University of Nottingham, Nottingham NG7 2UH, U.K
| | - Mengjie Liu
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, 381 Royal Parade, Parkville, Victoria 3052, Australia
| | - Simon J Mountford
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, 381 Royal Parade, Parkville, Victoria 3052, Australia
| | - Stephen J Briddon
- Institute of Cell Signalling, School of Biomedical Sciences, Queen's Medical Centre, University of Nottingham, Nottingham NG7 2UH, U.K
| | - Nicholas D Holliday
- Institute of Cell Signalling, School of Biomedical Sciences, Queen's Medical Centre, University of Nottingham, Nottingham NG7 2UH, U.K
| | - Philip E Thompson
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, 381 Royal Parade, Parkville, Victoria 3052, Australia
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9
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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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10
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Sarkar-Banerjee S, Sayyed-Ahmad A, Prakash P, Cho KJ, Waxham MN, Hancock JF, Gorfe AA. Spatiotemporal Analysis of K-Ras Plasma Membrane Interactions Reveals Multiple High Order Homo-oligomeric Complexes. J Am Chem Soc 2017; 139:13466-13475. [PMID: 28863262 PMCID: PMC5663506 DOI: 10.1021/jacs.7b06292] [Citation(s) in RCA: 62] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Self-assembly of plasma membrane-associated Ras GTPases has major implications to the regulation of cell signaling. However, the structural basis of homo-oligomerization and the fractional distribution of oligomeric states remained undetermined. We have addressed these issues by deciphering the distribution of dimers and higher-order oligomers of K-Ras4B, the most frequently mutated Ras isoform in human cancers. We focused on the constitutively active G12V K-Ras and two of its variants, K101E and K101C/E107C, which respectively destabilize and stabilize oligomers. Using raster image correlation spectroscopy and number and brightness analysis combined with fluorescence recovery after photobleaching, fluorescence correlation spectroscopy and electron microscopy in live cells, we show that G12V K-Ras exists as a mixture of monomers, dimers and larger oligomers, while the K101E mutant is predominantly monomeric and K101C/E107C is dominated by oligomers. This observation demonstrates the ability of K-Ras to exist in multiple oligomeric states whose population can be altered by interfacial mutations. Using molecular modeling and simulations we further show that K-Ras uses two partially overlapping interfaces to form compositionally and topologically diverse oligomers. Our results thus provide the first detailed insight into the multiplicity, structure, and membrane organization of K-Ras homomers.
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Affiliation(s)
- Suparna Sarkar-Banerjee
- Department of Integrative Biology and Pharmacology, University of Texas Health Science Center at Houston, Houston, Texas 77030, United States
| | | | - Priyanka Prakash
- Department of Integrative Biology and Pharmacology, University of Texas Health Science Center at Houston, Houston, Texas 77030, United States
| | - Kwang-Jin Cho
- Department of Biochemistry and Molecular Biology, Boonshoft School of Medicine, Wright State University, Dayton, Ohio 45435, United States
| | - M. Neal Waxham
- Department of Neurobiology and Anatomy, University of Texas Health Science Center at Houston, Houston, Texas 77030, United States
| | - John F. Hancock
- Department of Integrative Biology and Pharmacology, University of Texas Health Science Center at Houston, Houston, Texas 77030, United States
| | - Alemayehu A. Gorfe
- Department of Integrative Biology and Pharmacology, University of Texas Health Science Center at Houston, Houston, Texas 77030, United States
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11
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Reiter E, Ayoub MA, Pellissier LP, Landomiel F, Musnier A, Tréfier A, Gandia J, De Pascali F, Tahir S, Yvinec R, Bruneau G, Poupon A, Crépieux P. β-arrestin signalling and bias in hormone-responsive GPCRs. Mol Cell Endocrinol 2017; 449:28-41. [PMID: 28174117 DOI: 10.1016/j.mce.2017.01.052] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/25/2016] [Revised: 01/31/2017] [Accepted: 01/31/2017] [Indexed: 12/14/2022]
Abstract
G protein-coupled receptors (GPCRs) play crucial roles in the ability of target organs to respond to hormonal cues. GPCRs' activation mechanisms have long been considered as a two-state process connecting the agonist-bound receptor to heterotrimeric G proteins. This view is now challenged as mounting evidence point to GPCRs being connected to large arrays of transduction mechanisms involving heterotrimeric G proteins as well as other players. Amongst the G protein-independent transduction mechanisms, those elicited by β-arrestins upon their recruitment to the active receptors are by far the best characterized and apply to most GPCRs. These concepts, in conjunction with remarkable advances made in the field of GPCR structural biology and biophysics, have supported the notion of ligand-selective signalling also known as pharmacological bias. Interestingly, recent reports have opened intriguing prospects to the way β-arrestins control GPCR-mediated signalling in space and time within the cells. In the present paper, we review the existing evidence linking endocrine-related GPCRs to β-arrestin recruitement, signalling, pathophysiological implications and selective activation by biased ligands and/or receptor modifications. Emerging concepts surrounding β-arrestin-mediated transduction are discussed in the light of the peculiarities of endocrine systems.
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Affiliation(s)
- Eric Reiter
- PRC, INRA, CNRS, IFCE, Université de Tours, 37380, Nouzilly, France.
| | - Mohammed Akli Ayoub
- PRC, INRA, CNRS, IFCE, Université de Tours, 37380, Nouzilly, France; LE STUDIUM(®) Loire Valley Institute for Advanced Studies, 45000, Orléans, France; Biology Department, College of Science, United Arab Emirates University, Al Ain, United Arab Emirates
| | | | - Flavie Landomiel
- PRC, INRA, CNRS, IFCE, Université de Tours, 37380, Nouzilly, France
| | - Astrid Musnier
- PRC, INRA, CNRS, IFCE, Université de Tours, 37380, Nouzilly, France
| | - Aurélie Tréfier
- PRC, INRA, CNRS, IFCE, Université de Tours, 37380, Nouzilly, France
| | - Jorge Gandia
- PRC, INRA, CNRS, IFCE, Université de Tours, 37380, Nouzilly, France
| | | | - Shifa Tahir
- PRC, INRA, CNRS, IFCE, Université de Tours, 37380, Nouzilly, France
| | - Romain Yvinec
- PRC, INRA, CNRS, IFCE, Université de Tours, 37380, Nouzilly, France
| | - Gilles Bruneau
- PRC, INRA, CNRS, IFCE, Université de Tours, 37380, Nouzilly, France
| | - Anne Poupon
- PRC, INRA, CNRS, IFCE, Université de Tours, 37380, Nouzilly, France
| | - Pascale Crépieux
- PRC, INRA, CNRS, IFCE, Université de Tours, 37380, Nouzilly, France
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12
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Dopamine Receptor Signaling in MIN6 β-Cells Revealed by Fluorescence Fluctuation Spectroscopy. Biophys J 2017; 111:609-618. [PMID: 27508444 DOI: 10.1016/j.bpj.2016.06.026] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2015] [Revised: 06/21/2016] [Accepted: 06/23/2016] [Indexed: 11/22/2022] Open
Abstract
Insulin secretion defects are central to the development of type II diabetes mellitus. Glucose stimulation of insulin secretion has been extensively studied, but its regulation by other stimuli such as incretins and neurotransmitters is not as well understood. We investigated the mechanisms underlying the inhibition of insulin secretion by dopamine, which is synthesized in pancreatic β-cells from circulating L-dopa. Previous research has shown that this inhibition is mediated primarily by activation of the dopamine receptor D3 subtype (DRD3), even though both DRD2 and DRD3 are expressed in β-cells. To understand this dichotomy, we investigated the dynamic interactions between the dopamine receptor subtypes and their G-proteins using two-color fluorescence fluctuation spectroscopy (FFS) of mouse MIN6 β-cells. We show that proper membrane localization of exogenous G-proteins depends on both the Gβ and Gγ subunits being overexpressed in the cell. Triple transfections of the dopamine receptor subtype and Gβ and Gγ subunits, each labeled with a different-colored fluorescent protein (FP), yielded plasma membrane expression of all three FPs and permitted an FFS evaluation of interactions between the dopamine receptors and the Gβγ complex. Upon dopamine stimulation, we measured a significant decrease in interactions between DRD3 and the Gβγ complex, which is consistent with receptor activation. In contrast, dopamine stimulation did not cause significant changes in the interactions between DRD2 and the Gβγ complex. These results demonstrate that two-color FFS is a powerful tool for measuring dynamic protein interactions in living cells, and show that preferential DRD3 signaling in β-cells occurs at the level of G-protein release.
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13
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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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14
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Smoyer CJ, Katta SS, Gardner JM, Stoltz L, McCroskey S, Bradford WD, McClain M, Smith SE, Slaughter BD, Unruh JR, Jaspersen SL. Analysis of membrane proteins localizing to the inner nuclear envelope in living cells. J Cell Biol 2016; 215:575-590. [PMID: 27831485 PMCID: PMC5119940 DOI: 10.1083/jcb.201607043] [Citation(s) in RCA: 66] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2016] [Revised: 10/03/2016] [Accepted: 10/18/2016] [Indexed: 12/31/2022] Open
Abstract
Understanding the protein composition of the inner nuclear membrane (INM) is fundamental to elucidating its role in normal nuclear function and in disease; however, few tools exist to examine the INM in living cells, and the INM-specific proteome remains poorly characterized. Here, we adapted split green fluorescent protein (split-GFP) to systematically localize known and predicted integral membrane proteins in Saccharomyces cerevisiae to the INM as opposed to the outer nuclear membrane. Our data suggest that components of the endoplasmic reticulum (ER) as well as other organelles are able to access the INM, particularly if they contain a small extraluminal domain. By pairing split-GFP with fluorescence correlation spectroscopy, we compared the composition of complexes at the INM and ER, finding that at least one is unique: Sbh2, but not Sbh1, has access to the INM. Collectively, our work provides a comprehensive analysis of transmembrane protein localization to the INM and paves the way for further research into INM composition and function.
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Affiliation(s)
| | | | | | - Lynn Stoltz
- Stowers Institute for Medical Research, Kansas City, MO 64110
| | - Scott McCroskey
- Stowers Institute for Medical Research, Kansas City, MO 64110
| | | | | | - Sarah E Smith
- Stowers Institute for Medical Research, Kansas City, MO 64110
| | | | - Jay R Unruh
- Stowers Institute for Medical Research, Kansas City, MO 64110
| | - Sue L Jaspersen
- Stowers Institute for Medical Research, Kansas City, MO 64110 .,Department of Molecular and Integrative Physiology, University of Kansas Medical Center, Kansas City, KS 66160
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15
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Melkes B, Hejnova L, Novotny J. Biased μ-opioid receptor agonists diversely regulate lateral mobility and functional coupling of the receptor to its cognate G proteins. Naunyn Schmiedebergs Arch Pharmacol 2016; 389:1289-1300. [PMID: 27600870 DOI: 10.1007/s00210-016-1293-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2016] [Accepted: 08/24/2016] [Indexed: 12/26/2022]
Abstract
There are some indications that biased μ-opioid ligands may diversely affect μ-opioid receptor (MOR) properties. Here, we used confocal fluorescence recovery after photobleaching (FRAP) to study the regulation by different MOR agonists of receptor movement within the plasma membrane of HEK293 cells stably expressing a functional yellow fluorescent protein (YFP)-tagged μ-opioid receptor (MOR-YFP). We found that the lateral mobility of MOR-YFP was increased by (D-Ala2,N-MePhe4,Gly5-ol)-enkephalin (DAMGO) and to a lesser extent also by morphine but decreased by endomorphin-2. Interestingly, cholesterol depletion strongly enhanced the ability of morphine to elevate receptor mobility but significantly reduced or even eliminated the effect of DAMGO and endomorphin-2, respectively. Moreover, the ability of DAMGO and endomorphin-2 to influence MOR-YFP movement was diminished by pertussis toxin treatment. The results obtained by agonist-stimulated [35S]GTPγS binding assays indicated that DAMGO exhibited higher efficacy than morphine and endomorphin-2 did and that the efficacy of DAMGO, contrary to the latter agonists, was enhanced by cholesterol depletion. Overall, our study provides clear evidence that biased MOR agonists diversely affect receptor mobility in plasma membranes as well as MOR/G protein coupling and that the regulatory effect of different ligands depends on the membrane cholesterol content. These findings help to delineate the fundamental properties of MOR regarding their interaction with biased MOR ligands and cognate G proteins.
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Affiliation(s)
- Barbora Melkes
- Department of Physiology, Faculty of Science, Charles University in Prague, Prague, Czech Republic
| | - Lucie Hejnova
- Department of Physiology, Faculty of Science, Charles University in Prague, Prague, Czech Republic
| | - Jiri Novotny
- Department of Physiology, Faculty of Science, Charles University in Prague, Prague, Czech Republic.
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16
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Liu M, Richardson RR, Mountford SJ, Zhang L, Tempone MH, Herzog H, Holliday ND, Thompson PE. Identification of a Cyanine-Dye Labeled Peptidic Ligand for Y1R and Y4R, Based upon the Neuropeptide Y C-Terminal Analogue, BVD-15. Bioconjug Chem 2016; 27:2166-75. [DOI: 10.1021/acs.bioconjchem.6b00376] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Mengjie Liu
- Medicinal
Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC 3052, Australia
| | - Rachel R. Richardson
- Cell
Signalling Research Group, School of Life Sciences, University of Nottingham, Queen’s Medical Centre, Nottingham, NG7 2UH, United Kingdom
| | - Simon J. Mountford
- Medicinal
Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC 3052, Australia
| | - Lei Zhang
- Neuroscience
Division, Garvan Institute of Medical Research, St. Vincent’s Hospital, Darlinghurst, NSW 2010, Australia
| | - Matheus H. Tempone
- Cell
Signalling Research Group, School of Life Sciences, University of Nottingham, Queen’s Medical Centre, Nottingham, NG7 2UH, United Kingdom
| | - Herbert Herzog
- Neuroscience
Division, Garvan Institute of Medical Research, St. Vincent’s Hospital, Darlinghurst, NSW 2010, Australia
| | - Nicholas D. Holliday
- Cell
Signalling Research Group, School of Life Sciences, University of Nottingham, Queen’s Medical Centre, Nottingham, NG7 2UH, United Kingdom
| | - Philip E. Thompson
- Medicinal
Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC 3052, Australia
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17
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Liu M, Mountford SJ, Richardson RR, Groenen M, Holliday ND, Thompson PE. Optically Pure, Structural, and Fluorescent Analogues of a Dimeric Y4 Receptor Agonist Derived by an Olefin Metathesis Approach. J Med Chem 2016; 59:6059-69. [DOI: 10.1021/acs.jmedchem.6b00310] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Mengjie Liu
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, Victoria 3052, Australia
| | - Simon J. Mountford
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, Victoria 3052, Australia
| | - Rachel R. Richardson
- School of Life Sciences, University of Nottingham, Queen’s Medical Centre. Derby Road, Nottingham NG7 2UH, United Kingdom
| | - Marleen Groenen
- School of Life Sciences, University of Nottingham, Queen’s Medical Centre. Derby Road, Nottingham NG7 2UH, United Kingdom
| | - Nicholas D. Holliday
- School of Life Sciences, University of Nottingham, Queen’s Medical Centre. Derby Road, Nottingham NG7 2UH, United Kingdom
| | - Philip E. Thompson
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, Victoria 3052, Australia
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18
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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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19
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Engidawork E, Aradska J, Lubec G. Neurotransmitter receptor complexes: methods for bioanalysis, their potentials and limitations. Rev Neurosci 2016; 27:111-33. [DOI: 10.1515/revneuro-2015-0034] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2015] [Accepted: 08/11/2015] [Indexed: 12/15/2022]
Abstract
AbstractNeurotransmitter receptors are key elements for brain function, but work so far has been focusing on the individual receptor subunits. It is, however, the receptor complexes that execute work rather than the subunits; of course, the multitude of possible combinations of the many receptors forming homomeric or heteromeric complexes is hampering studies. Moreover, not only receptors are observed in the complexes but also their corresponding protein kinases, phosphatases, and anchoring proteins, to name a few. Studying receptor complexes is still an analytical challenge. Thus far, no methods exist to unequivocally characterize or even quantify these assemblies. Major problems and limitations for the analysis exist, such as solubility, as the use of detergents is critical and may dissociate the receptor complexes as well as their separation in the native state. Gel-based techniques are able to separate and semiquantitatively quantify receptor complexes by subsequent immunochemical methods but do not allow the characterization of complex components. Immunoprecipitation methods are highly dependent on antibody availability and specificity, and the result of coimmunoprecipitation does not verify the direct physical interaction of proteins in the immunoprecipitate. Antibody shift assays are suitable to identify individual known proteins within a complex as are immunogold electron microscopic techniques and energy transfer technologies. Most techniques are simply showing the proximity of proteins rather than their physical interaction. Although fluorescence correlation spectroscopy is a promising technique, the use for quantification or comparing biological samples is limited. A lot of work remains to be done to provide tools for the characterization and quantification of receptor complexes in the brain.
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Affiliation(s)
| | - Jana Aradska
- 1Department of Pediatrics, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna, Austria
| | - Gert Lubec
- 3Department of Pharmaceutical Chemistry, University of Vienna, Althanstrasse 14, A-1090 Vienna, Austria
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20
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Wong K, Briddon SJ, Holliday ND, Kerr ID. Plasma membrane dynamics and tetrameric organisation of ABCG2 transporters in mammalian cells revealed by single particle imaging techniques. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2016; 1863:19-29. [DOI: 10.1016/j.bbamcr.2015.10.002] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Revised: 09/17/2015] [Accepted: 10/06/2015] [Indexed: 10/22/2022]
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21
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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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22
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Mörl K, Beck-Sickinger AG. Intracellular Trafficking of Neuropeptide Y Receptors. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2015; 132:73-96. [PMID: 26055055 DOI: 10.1016/bs.pmbts.2015.02.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The multireceptor multiligand system of neuropeptide Y receptors and their ligands is involved in the regulation of a multitude of physiological and pathophysiological processes. Specific expression patterns, ligand-binding modes, and signaling properties contribute to the complex network regulating distinct cellular responses. Intracellular trafficking processes are important key steps that are regulated in context with accessory proteins. These proteins exert their influence by interacting directly or indirectly with the receptors, causing modification of the receptors, or operating as scaffolds for the assembly of larger signaling complexes. On the intracellular receptor faces, sequence-specific motifs have been identified that play an important role in this process. Interestingly, it is also possible to influence the receptor internalization by modification of the peptide ligand.
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Affiliation(s)
- Karin Mörl
- Faculty of Biosciences, Pharmacy and Psychology, Institute of Biochemistry, Universität Leipzig, Leipzig, Germany.
| | - Annette G Beck-Sickinger
- Faculty of Biosciences, Pharmacy and Psychology, Institute of Biochemistry, Universität Leipzig, Leipzig, Germany
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23
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Kilpatrick LE, Humphrys LJ, Holliday ND. A G protein-coupled receptor dimer imaging assay reveals selectively modified pharmacology of neuropeptide Y Y1/Y5 receptor heterodimers. Mol Pharmacol 2015; 87:718-32. [PMID: 25637604 DOI: 10.1124/mol.114.095356] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The ability of G protein-coupled receptors (GPCRs) to form dimers, and particularly heterodimers, offers potential for targeted therapeutics with improved selectivity. However, studying dimer pharmacology is challenging, because of signaling cross-talk or because dimerization may often be transient in nature. Here we develop a system to isolate the pharmacology of precisely defined GPCR dimers, trapped by bimolecular fluorescence complementation (BiFC). Specific effects of agonist activation on such dimers are quantified using automated imaging and analysis of their internalization, controlled for by simultaneous assessment of endocytosis of one coexpressed protomer population. We applied this BiFC system to study example neuropeptide Y (NPY) Y1 receptor dimers. Incorporation of binding-site or phosphorylation-site mutations into just one protomer of a Y1/Y1 BiFC homodimer had no impact on efficient NPY-stimulated endocytosis, demonstrating that single-site agonist occupancy, and one phosphorylated monomer within this dimer, was sufficient. For two Y1 receptor heterodimer combinations (with the Y4 receptor or β2-adrenoceptor), agonist and antagonist pharmacology was explained by independent actions on the respective orthosteric binding sites. However, Y1/Y5 receptor BiFC dimers, compared with the constituent subtypes, were characterized by reduced potency and efficacy of Y5-selective peptide agonists, the inactivity of Y1-selective antagonists, and a change from surmountable to nonsurmountable antagonism for three unrelated Y5 antagonists. Thus, allosteric interactions between Y1 and Y5 receptors modify the pharmacology of the heterodimer, with implications for potential antiobesity agents that target centrally coexpressed Y1 and Y5 receptors to suppress appetite.
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Affiliation(s)
- Laura E Kilpatrick
- School of Life Sciences, University of Nottingham, The Medical School, Queen's Medical Centre, Nottingham, United Kingdom
| | - Laura J Humphrys
- School of Life Sciences, University of Nottingham, The Medical School, Queen's Medical Centre, Nottingham, United Kingdom
| | - Nicholas D Holliday
- School of Life Sciences, University of Nottingham, The Medical School, Queen's Medical Centre, Nottingham, United Kingdom
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24
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Weidemann T, Mücksch J, Schwille P. Fluorescence fluctuation microscopy: a diversified arsenal of methods to investigate molecular dynamics inside cells. Curr Opin Struct Biol 2014; 28:69-76. [DOI: 10.1016/j.sbi.2014.07.008] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2014] [Accepted: 07/11/2014] [Indexed: 11/26/2022]
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25
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Carayon K, Moulédous L, Combedazou A, Mazères S, Haanappel E, Salomé L, Mollereau C. Heterologous regulation of Mu-opioid (MOP) receptor mobility in the membrane of SH-SY5Y cells. J Biol Chem 2014; 289:28697-706. [PMID: 25183007 DOI: 10.1074/jbc.m114.588558] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The dynamic organization of G protein-coupled receptors in the plasma membrane is suspected of playing a role in their function. The regulation of the diffusion mode of the mu-opioid (MOP) receptor was previously shown to be agonist-specific. Here we investigate the regulation of MOP receptor diffusion by heterologous activation of other G protein-coupled receptors and characterize the dynamic properties of the MOP receptor within the heterodimer MOP/neuropeptide FF (NPFF2) receptor. The data show that the dynamics and signaling of the MOP receptor in SH-SY5Y cells are modified by the activation of α2-adrenergic and NPFF2 receptors, but not by the activation of receptors not described to interact with the opioid receptor. By combining, for the first time, fluorescence recovery after photobleaching at variable radius experiments with bimolecular fluorescence complementation, we show that the MOP/NPFF2 heterodimer adopts a specific diffusion behavior that corresponds to a mix of the dynamic properties of both MOP and NPFF2 receptors. Altogether, the data suggest that heterologous regulation is accompanied by a specific organization of receptors in the membrane.
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Affiliation(s)
- Kévin Carayon
- From the Institut de Pharmacologie et Biologie Structurale, UMR5089 CNRS/Université de Toulouse, 31077 Toulouse, France
| | - Lionel Moulédous
- From the Institut de Pharmacologie et Biologie Structurale, UMR5089 CNRS/Université de Toulouse, 31077 Toulouse, France
| | - Anne Combedazou
- From the Institut de Pharmacologie et Biologie Structurale, UMR5089 CNRS/Université de Toulouse, 31077 Toulouse, France
| | - Serge Mazères
- From the Institut de Pharmacologie et Biologie Structurale, UMR5089 CNRS/Université de Toulouse, 31077 Toulouse, France
| | - Evert Haanappel
- From the Institut de Pharmacologie et Biologie Structurale, UMR5089 CNRS/Université de Toulouse, 31077 Toulouse, France
| | - Laurence Salomé
- From the Institut de Pharmacologie et Biologie Structurale, UMR5089 CNRS/Université de Toulouse, 31077 Toulouse, France
| | - Catherine Mollereau
- From the Institut de Pharmacologie et Biologie Structurale, UMR5089 CNRS/Université de Toulouse, 31077 Toulouse, France
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26
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Mountford SJ, Liu M, Zhang L, Groenen M, Herzog H, Holliday ND, Thompson PE. Synthetic routes to the Neuropeptide Y Y1 receptor antagonist 1229U91 and related analogues for SAR studies and cell-based imaging. Org Biomol Chem 2014; 12:3271-81. [PMID: 24733083 DOI: 10.1039/c4ob00176a] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The potent Y1 receptor antagonist, 1229U91 has an unusual cyclic dimer structure that makes syntheses of analogue series quite challenging. We have examined three new routes to the synthesis of such peptides that has given access to novel structural variants including heterodimeric compounds, ring size variants and labelled conjugates. These compounds, including a fluorescently labelled analogue VIII show potent antagonism that can be utilised in studying Y1 receptor pharmacology.
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Affiliation(s)
- Simon J Mountford
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, 381 Royal Parade, Parkville, VIC 3052, Australia.
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27
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Recent applications of fluorescence correlation spectroscopy in live systems. FEBS Lett 2014; 588:3571-84. [PMID: 24726724 DOI: 10.1016/j.febslet.2014.03.056] [Citation(s) in RCA: 84] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2014] [Revised: 03/29/2014] [Accepted: 03/31/2014] [Indexed: 11/20/2022]
Abstract
Fluorescence correlation spectroscopy (FCS) is a widely used technique in biophysics and has helped address many questions in the life sciences. It provides important advantages compared to other fluorescence and biophysical methods. Its single molecule sensitivity allows measuring proteins within biological samples at physiological concentrations without the need of overexpression. It provides quantitative data on concentrations, diffusion coefficients, molecular transport and interactions even in live organisms. And its reliance on simple fluorescence intensity and its fluctuations makes it widely applicable. In this review we focus on applications of FCS in live samples, with an emphasis on work in the last 5 years, in the hope to provide an overview of the present capabilities of FCS to address biologically relevant questions.
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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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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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Herrick-Davis K, Grinde E, Cowan A, Mazurkiewicz JE. Fluorescence correlation spectroscopy analysis of serotonin, adrenergic, muscarinic, and dopamine receptor dimerization: the oligomer number puzzle. Mol Pharmacol 2013; 84:630-42. [PMID: 23907214 DOI: 10.1124/mol.113.087072] [Citation(s) in RCA: 89] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The issue of G protein-coupled receptor (GPCR) oligomer status has not been resolved. Although many studies have provided evidence in favor of receptor-receptor interactions, there is no consensus as to the exact oligomer size of class A GPCRs. Previous studies have reported monomers, dimers, tetramers, and higher-order oligomers. In the present study, this issue was examined using fluorescence correlation spectroscopy (FCS) with photon counting histogram (PCH) analysis, a sensitive method for monitoring diffusion and oligomer size of plasma membrane proteins. Six different class A GPCRs were selected from the serotonin (5-HT2A), adrenergic (α1b-AR and β2-AR), muscarinic (M1 and M2), and dopamine (D1) receptor families. Each GPCR was C-terminally labeled with green fluorescent protein (GFP) or yellow fluorescent protein (YFP) and expressed in human embryonic kidney 293 cells. FCS provided plasma membrane diffusion coefficients on the order of 7.5 × 10(-9) cm(2)/s. PCH molecular brightness analysis was used to determine the GPCR oligomer size. Known monomeric (CD-86) and dimeric (CD-28) receptors with GFP and YFP tags were used as controls to determine the molecular brightness of monomers and dimers. PCH analysis of fluorescence-tagged GPCRs revealed molecular brightness values that were twice the monomeric controls and similar to the dimeric controls. Reduced χ(2) analyses of the PCH data best fit a model for a homogeneous population of homodimers, without tetramers or higher-order oligomers. The homodimer configuration was unaltered by agonist treatment and was stable over a 10-fold range of receptor expression level. The results of this study demonstrate that biogenic amine receptors freely diffusing within the plasma membrane are predominantly homodimers.
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Affiliation(s)
- Katharine Herrick-Davis
- Center for Neuropharmacology and Neuroscience, Albany Medical College, Albany, New York (K.H.-D., E.G., J.E.M.); and Center for Cell Analysis and Modeling, University of Connecticut Health Center, Farmington, Connecticut (A.C.)
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Jameson DM, James NG, Albanesi JP. Fluorescence fluctuation spectroscopy approaches to the study of receptors in live cells. Methods Enzymol 2013; 519:87-113. [PMID: 23280108 DOI: 10.1016/b978-0-12-405539-1.00003-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Communication between cells and their environment, including other cells, is often mediated by cell surface receptors. Fluorescence methodologies are among the most important techniques used to study receptors and their interactions, and in the past decade, fluorescence fluctuation spectroscopy (FFS) approaches have been increasingly utilized. In this overview, we illustrate how diverse FFS approaches have been used to elucidate important aspects of receptor systems, including interactions of receptors with their ligands and receptor oligomerization and clustering. We also describe the most popular methods used to introduce fluorescent moieties into the biological systems. Finally, specific attention will be given to cell maintenance and transfection strategies especially as related to microscopy studies.
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Affiliation(s)
- David M Jameson
- Department of Cell and Molecular Biology, John A. Burns School of Medicine, University of Hawaii, Honolulu, Hawaii, USA.
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Zhao J, Pei G. Arrestins in metabolic regulation. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2013; 118:413-27. [PMID: 23764063 DOI: 10.1016/b978-0-12-394440-5.00016-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
This review summarizes the regulatory roles of β-arrestins in whole-body energy balance, body weight control, and carbohydrate and lipid homeostasis. Much research has pointed in the direction of the functions of β-arrestins in mediating desensitization and endocytosis of G protein-coupled receptors as well as in activating the receptor/β-arrestin/ERK signaling pathway being crucial for metabolic regulation. Furthermore, β-arrestins form diverse signal complexes for the activation of the downstream cassettes for the body's metabolic reactions. However, further studies are required to fully address the emerging roles of β-arrestins in metabolic regulation and related diseases.
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Affiliation(s)
- Jian Zhao
- State Key Laboratory of Cell Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, PR China
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Walther C, Ferguson SSG. Arrestins: role in the desensitization, sequestration, and vesicular trafficking of G protein-coupled receptors. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2013; 118:93-113. [PMID: 23764051 DOI: 10.1016/b978-0-12-394440-5.00004-8] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Over the years, β-arrestins have emerged as multifunctional molecular scaffolding proteins regulating almost every imaginable G protein-coupled receptor (GPCR) function. Originally discovered as GPCR-desensitizing molecules, they have been shown to also serve as important regulators of GPCR signaling, sequestration, and vesicular trafficking. This broad functional role implicates β-arrestins as key regulatory proteins for cellular function. Hence, this chapter summarizes the current understanding of the β-arrestin family's unique ability to control the kinetics as well as the extent of GPCR activity at the level of desensitization, sequestration, and subsequent intracellular trafficking.
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Affiliation(s)
- Cornelia Walther
- J. Allyn Taylor Centre for Cell Biology, Robarts Research Institute, Western University Canada, London, Ontario, Canada
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Felce JH, Davis SJ. Unraveling receptor stoichiometry using bret. Front Endocrinol (Lausanne) 2012; 3:86. [PMID: 22807923 PMCID: PMC3394964 DOI: 10.3389/fendo.2012.00086] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/18/2012] [Accepted: 06/23/2012] [Indexed: 11/13/2022] Open
Affiliation(s)
- James H. Felce
- T-cell Biology Group, Nuffield Department of Clinical Medicine, University of OxfordOxford, UK
- MRC Human Immunology Unit, University of Oxford, John Radcliffe HospitalOxford, UK
| | - Simon J. Davis
- T-cell Biology Group, Nuffield Department of Clinical Medicine, University of OxfordOxford, UK
- MRC Human Immunology Unit, University of Oxford, John Radcliffe HospitalOxford, UK
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