1
|
Chen G, Obal D. Detecting and measuring of GPCR signaling - comparison of human induced pluripotent stem cells and immortal cell lines. Front Endocrinol (Lausanne) 2023; 14:1179600. [PMID: 37293485 PMCID: PMC10244570 DOI: 10.3389/fendo.2023.1179600] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/04/2023] [Accepted: 04/12/2023] [Indexed: 06/10/2023] Open
Abstract
G protein-coupled receptors (GPCRs) are a large family of transmembrane proteins that play a major role in many physiological processes, and thus GPCR-targeted drug development has been widely promoted. Although research findings generated in immortal cell lines have contributed to the advancement of the GPCR field, the homogenous genetic backgrounds, and the overexpression of GPCRs in these cell lines make it difficult to correlate the results with clinical patients. Human induced pluripotent stem cells (hiPSCs) have the potential to overcome these limitations, because they contain patient specific genetic information and can differentiate into numerous cell types. To detect GPCRs in hiPSCs, highly selective labeling and sensitive imaging techniques are required. This review summarizes existing resonance energy transfer and protein complementation assay technologies, as well as existing and new labeling methods. The difficulties of extending existing detection methods to hiPSCs are discussed, as well as the potential of hiPSCs to expand GPCR research towards personalized medicine.
Collapse
Affiliation(s)
- Gaoxian Chen
- Department of Anesthesiology, Perioperative, and Pain Medicine, Stanford University, Stanford, CA, United States
- Stanford Cardiovascular Institute, Stanford University, Stanford, CA, United States
| | - Detlef Obal
- Department of Anesthesiology, Perioperative, and Pain Medicine, Stanford University, Stanford, CA, United States
- Stanford Cardiovascular Institute, Stanford University, Stanford, CA, United States
| |
Collapse
|
2
|
Wang D, Yao Y, Wang S, Hou Y, Zhao L, Wang H, Chen H, Xu J. Structural Insights into M1 Muscarinic Acetylcholine Receptor Signaling Bias between Gαq and β-Arrestin through BRET Assays and Molecular Docking. Int J Mol Sci 2023; 24:ijms24087356. [PMID: 37108518 PMCID: PMC10138654 DOI: 10.3390/ijms24087356] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Revised: 04/12/2023] [Accepted: 04/13/2023] [Indexed: 04/29/2023] Open
Abstract
The selectivity of drugs for G protein-coupled receptor (GPCR) signaling pathways is crucial for their therapeutic efficacy. Different agonists can cause receptors to recruit effector proteins at varying levels, thus inducing different signaling responses, called signaling bias. Although several GPCR-biased drugs are currently being developed, only a limited number of biased ligands have been identified regarding their signaling bias for the M1 muscarinic acetylcholine receptor (M1mAChR), and the mechanism is not yet well understood. In this study, we utilized bioluminescence resonance energy transfer (BRET) assays to compare the efficacy of six agonists in inducing Gαq and β-arrestin2 binding to M1mAChR. Our findings reveal notable variations in agonist efficacy in the recruitment of Gαq and β-arrestin2. Pilocarpine preferentially promoted the recruitment of β-arrestin2 (∆∆RAi = -0.5), while McN-A-343 (∆∆RAi = 1.5), Xanomeline (∆∆RAi = 0.6), and Iperoxo (∆∆RAi = 0.3) exhibited a preference for the recruitment of Gαq. We also used commercial methods to verify the agonists and obtained consistent results. Molecular docking revealed that certain residues (e.g., Y404, located in TM7 of M1mAChR) could play crucial roles in Gαq signaling bias by interacting with McN-A-343, Xanomeline, and Iperoxo, whereas other residues (e.g., W378 and Y381, located in TM6) contributed to β-arrestin recruitment by interacting with Pilocarpine. The preference of activated M1mAChR for different effectors may be due to significant conformational changes induced by biased agonists. By characterizing bias towards Gαq and β-arrestin2 recruitment, our study provides insights into M1mAChR signaling bias.
Collapse
Affiliation(s)
- Dongxue Wang
- Institute of Interdisciplinary Integrative Medicine Research, Shanghai University of Traditional Chinese Medicine, Shanghai 201203, China
- Academy of Integrative Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai 201203, China
| | - Yunjin Yao
- Institute of Interdisciplinary Integrative Medicine Research, Shanghai University of Traditional Chinese Medicine, Shanghai 201203, China
- Academy of Integrative Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai 201203, China
| | - Shiqi Wang
- Institute of Interdisciplinary Integrative Medicine Research, Shanghai University of Traditional Chinese Medicine, Shanghai 201203, China
- Academy of Integrative Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai 201203, China
| | - Yifei Hou
- Institute of Interdisciplinary Integrative Medicine Research, Shanghai University of Traditional Chinese Medicine, Shanghai 201203, China
- Academy of Integrative Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai 201203, China
| | - Lanxue Zhao
- Department of Pharmacology and Chemical Biology, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Hao Wang
- Department of Pharmacology and Chemical Biology, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
- Shanghai Universities Collaborative Innovation Center for Translational Medicine, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Hongzhuan Chen
- Institute of Interdisciplinary Integrative Medicine Research, Shanghai University of Traditional Chinese Medicine, Shanghai 201203, China
- Shanghai Frontiers Science Center of TCM Chemical Biology, Shanghai University of Traditional Chinese Medicine, Shanghai 201203, China
| | - Jianrong Xu
- Academy of Integrative Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai 201203, China
- Shanghai Frontiers Science Center of TCM Chemical Biology, Shanghai University of Traditional Chinese Medicine, Shanghai 201203, China
| |
Collapse
|
3
|
Flores-Romero H, García-Sáez AJ. MERLIN: A BRET-Based Proximity Biosensor for Studying Mitochondria-ER Contact Sites. Methods Mol Biol 2022; 2525:197-205. [PMID: 35836069 DOI: 10.1007/978-1-0716-2473-9_14] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
The contacts between the endoplasmic reticulum (ER) and mitochondria play a fundamental role in a wide variety of cellular processes, like the exchange of calcium and lipids between both organelles, as well as in apoptosis and in autophagy signaling. Despite their importance, due to their dynamic and heterogeneous nature, we still lack understanding of the molecular composition, structure, and regulation of these structures. In this chapter, we introduce a new bioluminescence resonance energy transfer (BRET)-based biosensor for the quantitative analysis of mitochondria-ER interorganellar distances without perturbing their natural environment, which we call MERLIN (mitochondria ER length indicator nanosensor). Here, we describe the rationale behind the MERLIN biosensor, detail the experimental setup and methodology, and provide tips for troubleshooting.
Collapse
Affiliation(s)
- Hector Flores-Romero
- Institute for Genetics, University of Cologne, Cologne, Germany
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Cologne, Germany
- Interfaculty Institute of Biochemistry, Eberhard-Karls-Universität Tübingen, Tübingen, Germany
| | - Ana J García-Sáez
- Institute for Genetics, University of Cologne, Cologne, Germany.
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Cologne, Germany.
- Interfaculty Institute of Biochemistry, Eberhard-Karls-Universität Tübingen, Tübingen, Germany.
| |
Collapse
|
4
|
Parichatikanond W, Kyaw ETH, Madreiter-Sokolowski CT, Mangmool S. BRET-based assay to specifically monitor β 2AR/GRK2 interaction and β-arrestin2 conformational change upon βAR stimulation. Methods Cell Biol 2021; 166:67-81. [PMID: 34752340 DOI: 10.1016/bs.mcb.2021.06.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The β-adrenergic receptors (βARs) are members of G protein-coupled receptor (GPCR) family and have been one of the most important GPCRs for studying receptor endocytosis and signaling pathway. Agonist binding of βARs leads to an activation of G proteins and their canonical effectors. In a parallel way, βAR stimulation triggers the termination of its signals by receptor desensitization. This termination process is initiated by G protein-coupled receptor kinase (GRK)-induced βAR phosphorylation that promotes the recruitment of β-arrestins to phosphorylated βAR. The uncoupled βARs which formed a complex with GRK and β-arrestin subsequently internalize into the cytosol. In addition, GRKs and β-arrestins also act as scaffolding proteins and signal transducers in their own functions to modulate various downstream effectors. Upon translocation to the βAR, β-arrestin is believed to undergo an important conformational change in the structure that is necessary for its signal transduction. The bioluminescence resonance energy transfer (BRET) technique involves the fusion of donor (luciferase) and acceptor (fluorescent) molecules to the interested proteins. Co-expression of these fusion proteins enables direct detection of their interactions in living cells. Here we describe the use of our established BRET technique to track the interaction of βAR with both GRK and β-arrestin. The assay described here allows the measurement of the BRET signal for detecting the interaction of β2AR with GRK2 and the conformational change of β-arrestin2 following βAR stimulation.
Collapse
Affiliation(s)
| | - Ei Thet Htar Kyaw
- Pharmacology and Biomolecular Science Graduate Program, Faculty of Pharmacy, Mahidol University, Bangkok, Thailand
| | | | - Supachoke Mangmool
- Department of Pharmacology, Faculty of Science, Mahidol University, Bangkok, Thailand.
| |
Collapse
|
5
|
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.
Collapse
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
| |
Collapse
|
6
|
Monitoring Opioid Receptor Interaction in Living Cells by Bioluminescence Resonance Energy Transfer (BRET). Methods Mol Biol 2020. [PMID: 32975787 DOI: 10.1007/978-1-0716-0884-5_4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
Abstract
Bioluminescence resonance energy transfer (BRET ) is a natural phenomenon that has been successfully applied for the study of protein-protein interactions, including opioid receptor oligomers. The discovery of opioid receptor homomers and heteromers has brought to the discovery of new functions and new way of signaling and trafficking; therefore, opioid receptor oligomers may be considered as novel drug targets. Fusing receptors of interest with Renilla luciferase and with a fluorescent protein (such as EYFP ) it is possible to study opioid receptor dimerization using BRET .
Collapse
|
7
|
Zrein A, Bagher AM, Young AP, Denovan-Wright EM, Kelly MEM. Endothelin receptor heteromerization inhibits β-arrestin function in HEK293 cells. Can J Physiol Pharmacol 2020; 98:531-540. [PMID: 32744876 DOI: 10.1139/cjpp-2019-0620] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The endothelin receptor A (ETA) and endothelin receptor B (ETB) are G protein-coupled receptors that are co-expressed in vascular smooth muscle cells. Endothelin-1 (ET-1) activates endothelin receptors to cause microvascular vasoconstriction. Previous studies have shown that heteromerization between ETA and ETB prolongs Ca2+ transients, leading to prolongation of Gαq-dependent signaling and sustained vasoconstriction. We hypothesized that these effects are in part mediated by the resistance of ETA/ETB heteromers to β-arrestin recruitment and subsequent desensitization. Using bioluminescence resonance energy transfer 2 (BRET2), we found that ETB has a relatively equal affinity to form either homomers or heteromers with ETA when co-expressed in the human embryonic kidney 293 (HEK293) cells. When co-expressed, activation of ETA and ETB by ET-1 caused a heteromer-specific reduction and delay in β-arrestin-2 recruitment with a corresponding reduction and delay in ET-1-induced ETA/ETB co-internalization. Furthermore, the co-expression of ETA and ETB inhibited ET-1-induced β-arrestin-1-dependent extracellular signal-regulated kinase (ERK) phosphorylation while prolonging ET-1-induced Gαq-dependent ERK phosphorylation. ETA/ETB heteromerization mediates the long-lasting vasoconstrictor response to ET-1 by the prolongation of Gαq-dependent signaling and inhibition of β-arrestin function.
Collapse
Affiliation(s)
- Adel Zrein
- Department of Pharmacology, Dalhousie University, Halifax, NS B3H 4R2, Canada
| | - Amina M Bagher
- Department of Pharmacology and Toxicology, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Alexander P Young
- Department of Pharmacology, Dalhousie University, Halifax, NS B3H 4R2, Canada
| | | | - Melanie E M Kelly
- Department of Pharmacology, Dalhousie University, Halifax, NS B3H 4R2, Canada.,Department of Ophthalmology and Visual Sciences, Dalhousie University, Halifax, NS B3H 4R2, Canada
| |
Collapse
|
8
|
Coriano C, Powell E, Xu W. Monitoring Ligand-Activated Protein-Protein Interactions Using Bioluminescent Resonance Energy Transfer (BRET) Assay. Methods Mol Biol 2016; 1473:3-15. [PMID: 27518618 DOI: 10.1007/978-1-4939-6346-1_1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The bioluminescent resonance energy transfer (BRET) assay has been extensively used in cell-based and in vivo imaging systems for detecting protein-protein interactions in the native environment of living cells. These protein-protein interactions are essential for the functional response of many signaling pathways to environmental chemicals. BRET has been used as a toxicological tool for identifying chemicals that either induce or inhibit these protein-protein interactions. This chapter focuses on describing the toxicological applications of BRET and its optimization as a high-throughput detection system in live cells. Here we review the construction of BRET fusion proteins, describe the BRET methodology, and outline strategies to overcome obstacles that may arise. Furthermore, we describe the advantage of BRET over other resonance energy transfer methods for monitoring protein-protein interactions.
Collapse
Affiliation(s)
- Carlos Coriano
- Department of Oncology, University of Wisconsin-Madison, 7459 WIMR II, 1111 Highland Avenue, Madison, WI, 53705-2275, USA
| | - Emily Powell
- Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, 77030, USA
| | - Wei Xu
- Department of Oncology, University of Wisconsin-Madison, 7459 WIMR II, 1111 Highland Avenue, Madison, WI, 53705-2275, USA.
| |
Collapse
|
9
|
Chason RJ, Kang JH, Gerkowicz SA, Dufau ML, Catt KJ, Segars JH. GnRH agonist reduces estrogen receptor dimerization in GT1-7 cells: evidence for cross-talk between membrane-initiated estrogen and GnRH signaling. Mol Cell Endocrinol 2015; 404:67-74. [PMID: 25619861 PMCID: PMC4590284 DOI: 10.1016/j.mce.2015.01.023] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/25/2014] [Revised: 01/18/2015] [Accepted: 01/19/2015] [Indexed: 12/27/2022]
Abstract
17β-estradiol (E2), a key participant on the initiation of the LH surge, exerts both positive and negative feedback on GnRH neurons. We sought to investigate potential interactions between estrogen receptors alpha (ERα) and beta (ERβ) and gonadotropin releasing hormone receptor (GnRH-R) in GT1-7 cells. Radioligand binding studies demonstrated a significant decrease in saturation E2 binding in cells treated with GnRH agonist. Conversely, there was a significant reduction in GnRH binding in GT1-7 cells treated with E2. In BRET(1) experiments, ERα-ERα dimerization was suppressed in GT1-7 cells treated with GnRH agonist (p < 0.05). There was no evidence of direct interaction between ERs and GnRH-R. This study provides the first evidence of reduced ERα homodimerization by GnRH agonist. Collectively, these findings demonstrate significant cross-talk between membrane-initiated GnRH and E2 signaling in GT1-7 cells.
Collapse
Affiliation(s)
- Rebecca J Chason
- Program in Reproductive and Adult Endocrinology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, 10 CRC, Room 1E-3140, 10 Center Drive, MSC 1109, Bethesda, MD 20892-1109, USA
| | - Jung-Hoon Kang
- Section on Molecular Endocrinology, Program on Developmental Endocrinology and Genetics, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892-4510, USA
| | - Sabrina A Gerkowicz
- Department of Obstetrics and Gynecology, University of Miami, 1611 NW 12th Ave, Miami, FL 33136, USA
| | - Maria L Dufau
- Section on Molecular Endocrinology, Program on Developmental Endocrinology and Genetics, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892-4510, USA
| | - Kevin J Catt
- Endocrinology and Reproduction Research Branch, Section on Hormonal Regulation, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
| | - James H Segars
- Program in Reproductive and Adult Endocrinology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, 10 CRC, Room 1E-3140, 10 Center Drive, MSC 1109, Bethesda, MD 20892-1109, USA.
| |
Collapse
|
10
|
Baiula M. Monitoring opioid receptor dimerization in living cells by bioluminescence resonance energy transfer (BRET). Methods Mol Biol 2015; 1230:105-113. [PMID: 25293319 DOI: 10.1007/978-1-4939-1708-2_8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Bioluminescence resonance energy transfer (BRET) is a natural phenomenon that has been successfully applied for the study of protein-protein interactions, including opioid receptor oligomers. The discovery of opioid receptor homomers and heteromers has brought to the finding of new functions and new way of signaling and trafficking; therefore, opioid receptor oligomers may be considered as novel drug targets. Fusing receptors of interest with Renilla luciferase and with a fluorescent protein (such as EYFP), it is possible to study opioid receptor dimerization using BRET.
Collapse
Affiliation(s)
- Monica Baiula
- Department of Pharmacy and Biotechnology (FaBiT), University of Bologna, Via Irnerio 48, Bologna, 40126, Italy,
| |
Collapse
|
11
|
Jaeger WC, Seeber RM, Eidne KA, Pfleger KDG. Molecular determinants of orexin receptor-arrestin-ubiquitin complex formation. Br J Pharmacol 2014; 171:364-74. [PMID: 24206104 PMCID: PMC3904257 DOI: 10.1111/bph.12481] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2013] [Revised: 09/11/2013] [Accepted: 10/15/2013] [Indexed: 12/27/2022] Open
Abstract
BACKGROUND AND PURPOSE The orexin system regulates a multitude of key physiological processes, particularly involving maintenance of metabolic homeostasis. Consequently, there is considerable potential for pharmaceutical development for the treatment of disorders from narcolepsy to metabolic syndrome. It acts through the hormonal activity of two endogenous peptides, orexin A binding to orexin receptors 1 and 2 (OX₁ and OX₂) with similar affinity, and orexin B binding to OX₂ with higher affinity than OX₁ receptors. We have previously revealed data differentiating orexin receptor subtypes with respect to their relative stability in forming orexin receptor-arrestin-ubiquitin complexes measured by BRET. Recycling and cellular signalling distinctions were also observed. Here, we have investigated, using BRET, the molecular determinants involved in providing OX₂ receptors with greater β-arrestin-ubiquitin complex stability. EXPERIMENTAL APPROACH The contribution of the C-terminal tail of the OX receptors was investigated by bulk substitution and site-specific mutagenesis using BRET and inositol phosphate assays. KEY RESULTS Replacement of the OX₁ receptor C-terminus with that of the OX₂ receptor did not result in the expected gain of function, indicating a role for intracellular domain configuration in addition to primary structure. Furthermore, two out of the three putative serine/threonine clusters in the C-terminus were found to be involved in OX₂ receptor-β-arrestin-ubiquitin complex formation. CONCLUSIONS AND IMPLICATIONS This study provides fundamental insights into the molecular elements that influence receptor-arrestin-ubiquitin complex formation. Understanding how and why the orexin receptors can be functionally differentiated brings us closer to exploiting these receptors as drug targets.
Collapse
Affiliation(s)
- Werner C Jaeger
- Laboratory for Molecular Endocrinology-G Protein-Coupled Receptors, Western Australian Institute for Medical Research (WAIMR) and Centre for Medical Research, The University of Western Australia, Perth, WA, Australia
| | | | | | | |
Collapse
|
12
|
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.
Collapse
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:
| |
Collapse
|
13
|
Abstract
G-protein-coupled receptors (GPCRs) are the primary interaction partners for arrestins. The visual arrestins, arrestin1 and arrestin4, physiologically bind to only very few receptors, i.e., rhodopsin and the color opsins, respectively. In contrast, the ubiquitously expressed nonvisual variants β-arrestin1 and 2 bind to a large number of receptors in a fairly nonspecific manner. This binding requires two triggers, agonist activation and receptor phosphorylation by a G-protein-coupled receptor kinase (GRK). These two triggers are mediated by two different regions of the arrestins, the "phosphorylation sensor" in the core of the protein and a less well-defined "activation sensor." Binding appears to occur mostly in a 1:1 stoichiometry, involving the N-terminal domain of GPCRs, but in addition a second GPCR may loosely bind to the C-terminal domain when active receptors are abundant.Arrestin binding initially uncouples GPCRs from their G-proteins. It stabilizes receptors in an active conformation and also induces a conformational change in the arrestins that involves a rotation of the two domains relative to each other plus changes in the polar core. This conformational change appears to permit the interaction with further downstream proteins. The latter interaction, demonstrated mostly for β-arrestins, triggers receptor internalization as well as a number of nonclassical signaling pathways.Open questions concern the exact stoichiometry of the interaction, possible specificity with regard to the type of agonist and of GRK involved, selective regulation of downstream signaling (=biased signaling), and the options to use these mechanisms as therapeutic targets.
Collapse
Affiliation(s)
- Martin J Lohse
- Institute of Pharmacology and Toxicology, University of Würzburg, Versbacher Straße 9, 97078, Würzburg, Germany,
| | | |
Collapse
|
14
|
Siddiqui S, Cong WN, Daimon CM, Martin B, Maudsley S. BRET Biosensor Analysis of Receptor Tyrosine Kinase Functionality. Front Endocrinol (Lausanne) 2013; 4:46. [PMID: 23577003 PMCID: PMC3620488 DOI: 10.3389/fendo.2013.00046] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/07/2013] [Accepted: 03/26/2013] [Indexed: 01/20/2023] Open
Abstract
Bioluminescence resonance energy transfer (BRET) is an improved version of earlier resonance energy transfer technologies used for the analysis of biomolecular protein interaction. BRET analysis can be applied to many transmembrane receptor classes, however the majority of the early published literature on BRET has focused on G protein-coupled receptor (GPCR) research. In contrast, there is limited scientific literature using BRET to investigate receptor tyrosine kinase (RTK) activity. This limited investigation is surprising as RTKs often employ dimerization as a key factor in their activation, as well as being important therapeutic targets in medicine, especially in the cases of cancer, diabetes, neurodegenerative, and respiratory conditions. In this review, we consider an array of studies pertinent to RTKs and other non-GPCR receptor protein-protein signaling interactions; more specifically we discuss receptor-protein interactions involved in the transmission of signaling communication. We have provided an overview of functional BRET studies associated with the RTK superfamily involving: neurotrophic receptors [e.g., tropomyosin-related kinase (Trk) and p75 neurotrophin receptor (p75NTR)]; insulinotropic receptors [e.g., insulin receptor (IR) and insulin-like growth factor receptor (IGFR)] and growth factor receptors [e.g., ErbB receptors including the EGFR, the fibroblast growth factor receptor (FGFR), the vascular endothelial growth factor receptor (VEGFR) and the c-kit and platelet-derived growth factor receptor (PDGFR)]. In addition, we review BRET-mediated studies of other tyrosine kinase-associated receptors including cytokine receptors, i.e., leptin receptor (OB-R) and the growth hormone receptor (GHR). It is clear even from the relatively sparse experimental RTK BRET evidence that there is tremendous potential for this technological application for the functional investigation of RTK biology.
Collapse
Affiliation(s)
- Sana Siddiqui
- Receptor Pharmacology Unit, National Institute on Aging, National Institutes of HealthBaltimore, MD, USA
| | - Wei-Na Cong
- Metabolism Unit, National Institute on Aging, National Institutes of HealthBaltimore, MD, USA
| | - Caitlin M. Daimon
- Metabolism Unit, National Institute on Aging, National Institutes of HealthBaltimore, MD, USA
| | - Bronwen Martin
- Metabolism Unit, National Institute on Aging, National Institutes of HealthBaltimore, MD, USA
| | - Stuart Maudsley
- Receptor Pharmacology Unit, National Institute on Aging, National Institutes of HealthBaltimore, MD, USA
- *Correspondence: Stuart Maudsley, Receptor Pharmacology Unit, National Institute on Aging, National Institutes of Health, 251 Bayview Blvd., Suite 100, Baltimore, MD 21224, USA. e-mail:
| |
Collapse
|
15
|
Couturier C, Deprez B. Setting Up a Bioluminescence Resonance Energy Transfer High throughput Screening Assay to Search for Protein/Protein Interaction Inhibitors in Mammalian Cells. Front Endocrinol (Lausanne) 2012; 3:100. [PMID: 22973258 PMCID: PMC3438444 DOI: 10.3389/fendo.2012.00100] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/26/2012] [Accepted: 07/31/2012] [Indexed: 12/14/2022] Open
Abstract
Each step of the cell life and its response or adaptation to its environment are mediated by a network of protein/protein interactions termed "interactome." Our knowledge of this network keeps growing due to the development of sensitive techniques devoted to study these interactions. The bioluminescence resonance energy transfer (BRET) technique was primarily developed to allow the dynamic monitoring of protein/protein interactions (PPI) in living cells, and has widely been used to study receptor activation by intra- or extra-molecular conformational changes within receptors and activated complexes in mammal cells. Some interactions are described as crucial in human pathological processes, and a new class of drugs targeting them has recently emerged. The BRET method is well suited to identify inhibitors of PPI and here is described why and how to set up and optimize a high throughput screening assay based on BRET to search for such inhibitory compounds. The different parameters to take into account when developing such BRET assays in mammal cells are reviewed to give general guidelines: considerations on the targeted interaction, choice of BRET version, inducibility of the interaction, kinetic of the monitored interaction, and of the BRET reading, influence of substrate concentration, number of cells and medium composition used on the Z' factor, and expected interferences from colored or fluorescent compounds.
Collapse
Affiliation(s)
- Cyril Couturier
- Univ Lille Nord de FranceLille, France
- INSERM U761, Biostructures and Drug DiscoveryLille, France
- Université du Droit et de la Santé de LilleLille, France
- Institut Pasteur LilleLille, France
- Pôle de Recherche Interdisciplinaire sur le MédicamentLille, France
- *Correspondence: Cyril Couturier, UMR 761, Biostructure and Drug Discovery, Institut Pasteur de Lille, Université Lille 2, 1 rue du Pr Calmette, 59000 Lille, France. e-mail:
| | - Benoit Deprez
- Univ Lille Nord de FranceLille, France
- INSERM U761, Biostructures and Drug DiscoveryLille, France
- Université du Droit et de la Santé de LilleLille, France
- Institut Pasteur LilleLille, France
- Pôle de Recherche Interdisciplinaire sur le MédicamentLille, France
| |
Collapse
|
16
|
Salahpour A, Espinoza S, Masri B, Lam V, Barak LS, Gainetdinov RR. BRET biosensors to study GPCR biology, pharmacology, and signal transduction. Front Endocrinol (Lausanne) 2012; 3:105. [PMID: 22952466 PMCID: PMC3430160 DOI: 10.3389/fendo.2012.00105] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/01/2012] [Accepted: 08/11/2012] [Indexed: 12/29/2022] Open
Abstract
Bioluminescence resonance energy transfer (BRET)-based biosensors have been extensively used over the last decade to study protein-protein interactions and intracellular signal transduction in living cells. In this review, we discuss the various BRET biosensors that have been developed to investigate biology, pharmacology, and signaling of G protein-coupled receptors (GPCRs). GPCRs form two distinct types of multiprotein signal transduction complexes based upon their inclusion of G proteins or β-arrestins that can be differentially affected by drugs that exhibit functional selectivity toward G protein or β-arrestin signaling. BRET has been especially adept at illuminating the dynamics of protein-protein interactions between receptors, G proteins, β-arrestins, and their many binding partners in living cells; as well as measuring the formation and accumulation of second messengers following receptor activation. Specifically, we discuss in detail the application of BRET to study dopamine and trace amine receptors signaling, presenting examples of an exchange protein activated by cAMP biosensor to measure cAMP, β-arrestin biosensors to determine β-arrestin recruitment to the receptor, and dopamine D2 receptor and trace amine-associated receptor 1 biosensors to investigate heterodimerization between them. As the biochemical spectrum of BRET biosensors expands, the number of signaling pathways that can be measured will concomitantly increase. This will be particularly useful for the evaluation of functional selectivity in which the real-time BRET capability to measure distinct signaling modalities will dramatically shorten the time to characterize new generation of biased drugs. These emerging approaches will further expand the growing application of BRET in the screening for novel pharmacologically active compounds.
Collapse
Affiliation(s)
- Ali Salahpour
- Department of Pharmacology and Toxicology, University of TorontoToronto, ON, Canada
- *Correspondence: Ali Salahpour, Department of Pharmacology and Toxicology, University of Toronto, Room 4302, Medical Sciences Building, 1 King’s College Circle, Toronto, ON, Canada M5S 1A8. e-mail: ; Raul R. Gainetdinov, Department of Neuroscience and Brain Technologies, Istituto Italiano di Tecnologia, Via Morego 30, Genova 16167, Italy. e-mail:
| | - Stefano Espinoza
- Department of Neuroscience and Brain Technologies, Istituto Italiano di TecnologiaGenova, Italy
| | - Bernard Masri
- INSERM UMR 1037, Cancer Research Center of Toulouse and Université Paul SabatierToulouse, France
| | - Vincent Lam
- Department of Pharmacology and Toxicology, University of TorontoToronto, ON, Canada
| | - Larry S. Barak
- Department of Cell Biology, Duke UniversityDurham, NC, USA
| | - Raul R. Gainetdinov
- Department of Neuroscience and Brain Technologies, Istituto Italiano di TecnologiaGenova, Italy
- *Correspondence: Ali Salahpour, Department of Pharmacology and Toxicology, University of Toronto, Room 4302, Medical Sciences Building, 1 King’s College Circle, Toronto, ON, Canada M5S 1A8. e-mail: ; Raul R. Gainetdinov, Department of Neuroscience and Brain Technologies, Istituto Italiano di Tecnologia, Via Morego 30, Genova 16167, Italy. e-mail:
| |
Collapse
|
17
|
Abstract
Bioluminescence resonance energy transfer (BRET) has become an extremely valuable technology for the real-time study of protein-protein interactions in live cells. This technique is highly amenable to the monitoring of G protein-coupled receptor (GPCR)-protein interactions, especially involving scaffolding, regulatory and signaling proteins, such as β-arrestins, which are now known to have significant roles in addition to receptor desensitization. The BRET procedure utilizes heterologous coexpression of fusion proteins linking one protein of interest (e.g. a GPCR) to a bioluminescent donor enzyme, a variant of Renilla luciferase, and a second protein of interest (e.g. β-arrestin) to an acceptor fluorophore. If in close proximity, energy resulting from the rapid oxidation of a cell-permeable coelenterazine substrate by the donor will transfer to the acceptor, which in turn fluoresces at a longer characteristic wavelength. Therefore, the occurrence of such energy transfer implies that the proteins of interest fused to the donor and acceptor interact directly or as part of a complex. BRET detection can be carried out using scanning spectrometry or dual-filter luminometry. The latest improvements in BRET methodology have enabled live cell drug screening as well as monitoring of previously undetectable protein-protein complexes, including constitutive GPCR/β-arrestin interactions. Therefore, BRET is likely to play an increasingly important role in GPCR research and drug discovery over the coming years.
Collapse
Affiliation(s)
- Martina Kocan
- Drug Discovery Biology Laboratory, Monash Institute of Pharmaceutical Sciences and Department of Pharmacology, Monash University, Melbourne, Royal Parade, Parkvile, Victoria, Australia
| | | |
Collapse
|
18
|
Bohn LM, McDonald PH. Seeking Ligand Bias: Assessing GPCR Coupling to Beta-Arrestins for Drug Discovery. DRUG DISCOVERY TODAY. TECHNOLOGIES 2010; 7:e1-e94. [PMID: 21218149 DOI: 10.1016/j.ddtec.2010.06.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
G protein-coupled receptors (GPCR) are the major site of action for endogenous hormones and neurotransmitters. Early drug discovery efforts focused on determining whether ligands could engage G protein coupling and subsequently activate or inhibit cognate "second messengers." Gone are those simple days as we now realize that receptors can also couple βarrestins. As we delve into the complexity of ligand-directed signaling and receptosome scaffolds, we are faced with what may seem like endless possibilities triggered by receptor-ligand mediated events.
Collapse
Affiliation(s)
- Laura M Bohn
- Departments of Molecular Therapeutics and Neuroscience, The Scripps Research Institute, 130 Scripps Way #2A2, Jupiter, FL 33458,
| | | |
Collapse
|
19
|
Poisson C, Rollin S, Véronneau S, Bousquet SM, Larrivée JF, Le Gouill C, Boulay G, Stankova J, Rola-Pleszczynski M. Caveolae Facilitate but Are Not Essential for Platelet-Activating Factor-Mediated Calcium Mobilization and Extracellular Signal-Regulated Kinase Activation. THE JOURNAL OF IMMUNOLOGY 2009; 183:2747-57. [DOI: 10.4049/jimmunol.0802651] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
|
20
|
Böhme I, Beck-Sickinger AG. Illuminating the life of GPCRs. Cell Commun Signal 2009; 7:16. [PMID: 19602276 PMCID: PMC2726148 DOI: 10.1186/1478-811x-7-16] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2009] [Accepted: 07/14/2009] [Indexed: 01/19/2023] Open
Abstract
The investigation of biological systems highly depends on the possibilities that allow scientists to visualize and quantify biomolecules and their related activities in real-time and non-invasively. G-protein coupled receptors represent a family of very dynamic and highly regulated transmembrane proteins that are involved in various important physiological processes. Since their localization is not confined to the cell surface they have been a very attractive "moving target" and the understanding of their intracellular pathways as well as the identified protein-protein-interactions has had implications for therapeutic interventions. Recent and ongoing advances in both the establishment of a variety of labeling methods and the improvement of measuring and analyzing instrumentation, have made fluorescence techniques to an indispensable tool for GPCR imaging. The illumination of their complex life cycle, which includes receptor biosynthesis, membrane targeting, ligand binding, signaling, internalization, recycling and degradation, will provide new insights into the relationship between spatial receptor distribution and function. This review covers the existing technologies to track GPCRs in living cells. Fluorescent ligands, antibodies, auto-fluorescent proteins as well as the evolving technologies for chemical labeling with peptide- and protein-tags are described and their major applications concerning the GPCR life cycle are presented.
Collapse
Affiliation(s)
- Ilka Böhme
- Institute of Biochemistry, Faculty of Biosciences, Pharmacy and Psychology, Leipzig University, Brüderstr, 34, 04103 Leipzig, Germany.
| | | |
Collapse
|
21
|
Abstract
Although traditionally assumed to be monomeric signaling units, G-protein-coupled receptors (GPCRs) have been shown to exist as dimers/oligomers. Many chemokine receptors have been demonstrated to form homo-oligomers, and hetero-oligomerization between both pairs of chemokine receptors and chemokine receptors and other GPCRs has also been demonstrated. This chapter highlights some of the most common techniques used to investigate chemokine receptor oligomerization.
Collapse
Affiliation(s)
- Shirley Appelbe
- Neuroscience and Molecular Pharmacology, University of Glasgow, Glasgow, Scotland, United Kingdom
| | | |
Collapse
|
22
|
Pfleger KDG. Analysis of protein-protein interactions using bioluminescence resonance energy transfer. Methods Mol Biol 2009; 574:173-183. [PMID: 19685308 DOI: 10.1007/978-1-60327-321-3_14] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Knowledge of how and when proteins interact in living cells is fundamental to our understanding of cellular biology, and bioluminescence resonance energy transfer (BRET) provides an increasingly popular mechanism for studying these interactions in real time. The technique utilises heterologously expressed fusion proteins linking a bioluminescent donor or complementary acceptor fluorophore to proteins of interest. Resonance energy transfer between these fusion proteins is then detected when they are in close proximity, indicative of association either directly or as part of a complex. BRET is particularly useful for real-time monitoring of ligand-modulated interactions as dynamic changes in protein complex assembly can be observed in a live cell environment.
Collapse
Affiliation(s)
- Kevin D G Pfleger
- Western Australian Institute for Medical Research and Centre for Medical Research, University of Western Australia, Perth, Australia
| |
Collapse
|
23
|
Kocan M, Pfleger KDG. Detection of GPCR/beta-arrestin interactions in live cells using bioluminescence resonance energy transfer technology. Methods Mol Biol 2009; 552:305-17. [PMID: 19513659 DOI: 10.1007/978-1-60327-317-6_22] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Bioluminescence resonance energy transfer (BRET) is a powerful and increasingly popular technique for studying protein-protein interactions in live cells and real time. In particular, there has been considerable interest in the ability to monitor interactions between G protein-coupled receptors (GPCRs) and proteins that serve as key regulators of receptor function, such as beta-arrestin. The BRET methodology involves heterologous co-expression of genetically fused proteins that link one protein of interest (e.g., a GPCR) to a bioluminescent donor enzyme and a second protein of interest (e.g., beta-arrestin) to an acceptor fluorophore. If the fusion proteins are in close proximity, resonance energy will be transferred from the donor to the acceptor molecule and subsequent fluorescence from the acceptor can be detected at a characteristic wavelength. Such fluorescence is therefore indicative of the proteins of interest linked to the donor and the acceptor interacting directly or as part of a complex. In addition to monitoring protein-protein interactions to elucidate cellular function, BRET also has the exciting potential to become an important technique for live cell high-throughput screening for drugs targeting GPCRs, utilizing ligand-induced interactions with beta-arrestins.
Collapse
Affiliation(s)
- Martina Kocan
- Laboratory for Molecular Endocrinology, Western Australian Institute for Medical Research and Centre for Medical Research, University of Western Australia, Perth, Australia
| | | |
Collapse
|
24
|
Levi J, De A, Cheng Z, Gambhir SS. Bisdeoxycoelenterazine derivatives for improvement of bioluminescence resonance energy transfer assays. J Am Chem Soc 2007; 129:11900-1. [PMID: 17850082 PMCID: PMC4154798 DOI: 10.1021/ja073936h] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
25
|
Pfleger KDG, Seeber RM, Eidne KA. Bioluminescence resonance energy transfer (BRET) for the real-time detection of protein-protein interactions. Nat Protoc 2007; 1:337-45. [PMID: 17406254 DOI: 10.1038/nprot.2006.52] [Citation(s) in RCA: 159] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
A substantial range of protein-protein interactions can be readily monitored in real time using bioluminescence resonance energy transfer (BRET). The procedure involves heterologous coexpression of fusion proteins, which link proteins of interest to a bioluminescent donor enzyme or acceptor fluorophore. Energy transfer between these proteins is then detected. This protocol encompasses BRET1, BRET2 and the recently described eBRET, including selection of the donor, acceptor and substrate combination, fusion construct generation and validation, cell culture, fluorescence and luminescence detection, BRET detection and data analysis. The protocol is particularly suited to studying protein-protein interactions in live cells (adherent or in suspension), but cell extracts and purified proteins can also be used. Furthermore, although the procedure is illustrated with references to mammalian cell culture conditions, this protocol can be readily used for bacterial or plant studies. Once fusion proteins are generated and validated, the procedure typically takes 48-72 h depending on cell culture requirements.
Collapse
Affiliation(s)
- Kevin D G Pfleger
- 7TM Laboratory/Laboratory for Molecular Endocrinology, Western Australian Institute for Medical Research, University of Western Australia, Nedlands, Perth, Western Australia 6009, Australia.
| | | | | |
Collapse
|
26
|
McLaughlin JN, Patterson MM, Malik AB. Protease-activated receptor-3 (PAR3) regulates PAR1 signaling by receptor dimerization. Proc Natl Acad Sci U S A 2007; 104:5662-7. [PMID: 17376866 PMCID: PMC1838494 DOI: 10.1073/pnas.0700763104] [Citation(s) in RCA: 145] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Thrombin activates endothelial cell signaling by cleaving the protease-activated receptor-1 (PAR1). However, the function of the apparently nonsignaling receptor PAR3 also expressed in endothelial cells is unknown. We demonstrate here the crucial role of PAR3 in potentiating the responsiveness of PAR1 to thrombin. We tested the hypothesis that PAR1/PAR3 heterodimerization and its effect in modifying G protein selectivity was responsible for PAR3 regulation of PAR1 sensitivity. Using bioluminescent resonance energy transfer-2, we showed that PAR1 had comparable dimerization affinity for PAR3 as for itself. We observed increased Galpha(13) coupling between the PAR1/3 heterodimer compared with the PAR1/1 homodimer. Moreover, knockdown of PAR3 moderated the PAR1-activated increase in endothelial permeability. These results demonstrate a role of PAR3 in allosterically regulating PAR1 signaling governing increased endothelial permeability. Because PAR3 is a critical determinant of PAR1 function, targeting of PAR3 may mitigate the effects of PAR1 in activating endothelial responses such as vascular inflammation.
Collapse
Affiliation(s)
- Joseph N McLaughlin
- Department of Pharmacology and Center for Lung and Vascular Biology, University of Illinois College of Medicine, Chicago, IL 60612, USA.
| | | | | |
Collapse
|
27
|
|
28
|
Chapter 2.8 Application of bioassays/biosensors for the analysis of pharmaceuticals in environmental samples. ACTA ACUST UNITED AC 2007. [DOI: 10.1016/s0166-526x(07)50009-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
|
29
|
Krishnaveni MS, Hansen JL, Seeger W, Morty RE, Sheikh SP, Eickelberg O. Constitutive homo- and hetero-oligomerization of TbetaRII-B, an alternatively spliced variant of the mouse TGF-beta type II receptor. Biochem Biophys Res Commun 2006; 351:651-7. [PMID: 17078931 DOI: 10.1016/j.bbrc.2006.10.083] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2006] [Accepted: 10/17/2006] [Indexed: 12/31/2022]
Abstract
Transforming growth factor (TGF)-beta ligands signal through transmembrane type I and type II serine/threonine kinase receptors, which form heteromeric signalling complexes upon ligand binding. Type II TGF-beta receptors (TbetaRII) are reported to exist as homodimers at the cell surface, but the oligomerization pattern and dynamics of TbetaRII splice variants in live cells has not been demonstrated thus far. Using co-immunoprecipitation and bioluminescence resonance energy transfer (BRET), we demonstrate that the mouse TbetaRII receptor splice variant TbetaRII-B is capable of forming ligand-independent homodimers and heterodimers with TbetaRII. The homomeric interaction of mouse (m)TbetaRII-B isoforms, however, is less robust than the heteromeric interactions of mTbetaRII-B with wild-type TbetaRII, which indicates that these receptors may be more likely to heterodimerize when both receptors are expressed. Moreover, we demonstrate that mTbetaRII-B is a signalling receptor with ubiquitous tissue expression. Our study thus demonstrates previously unappreciated complex formation of TGF-beta type II receptors, and suggests that mTbetaRII-B can direct TGF-beta-induced signalling in vitro and in vivo.
Collapse
Affiliation(s)
- Manda S Krishnaveni
- Department of Medicine II, University of Giessen Lung Center, Justus-Liebig University, Giessen, Germany
| | | | | | | | | | | |
Collapse
|
30
|
Liang YJ, Wu DF, Yang LQ, Höllt V, Koch T. Interaction of the mu-opioid receptor with synaptophysin influences receptor trafficking and signaling. Mol Pharmacol 2006; 71:123-31. [PMID: 17005904 DOI: 10.1124/mol.106.026062] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
There is increasing evidence that the signal transduction of opioid receptors is modulated by receptor-associated proteins. In the search for proteins regulating mu-opioid receptor (MOPr) endocytosis, synaptophysin was found to bind to the rat micro-opioid receptor in yeast two-hybrid assay. Coimmunoprecipitation experiments and bioluminescence resonance energy transfer assays confirmed that the micro-opioid receptor constitutively interacts with synaptophysin in human embryonic kidney 293 cells overexpressing MOPr and synaptophysin. In this study, we show that overexpression of synaptophysin enhances the micro-opioid receptor endocytosis. One explanation for the observed effects is that synaptophysin recruits dynamin to the plasma membrane, facilitating fission of clathrin-coated vesicles. This suggestion is supported by our finding that overexpression of a synaptophysin truncation mutant, which breaks the interaction between synaptophysin and dynamin, prevents agonist-mediated micro-opioid receptor endocytosis. In addition, the synaptophysin-augmented micro-opioid receptor trafficking leads to attenuated agonist-induced receptor desensitization and faster receptor resensitization. Taken together, our findings strongly suggest that synaptophysin plays an important role in the regulation of micro-opioid receptor trafficking and signaling.
Collapse
Affiliation(s)
- Ying-Jian Liang
- Department of Pharmacology and Toxicology, Otto-von-Guericke University, Leipziger Str. 44, 39120 Magdeburg, Germany
| | | | | | | | | |
Collapse
|
31
|
Prinz A, Diskar M, Herberg FW. Application of bioluminescence resonance energy transfer (BRET) for biomolecular interaction studies. Chembiochem 2006; 7:1007-12. [PMID: 16755626 DOI: 10.1002/cbic.200600048] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Anke Prinz
- Kassel University, Department of Biochemistry, Kassel, Germany
| | | | | |
Collapse
|
32
|
Pfleger KDG, Eidne KA. Illuminating insights into protein-protein interactions using bioluminescence resonance energy transfer (BRET). Nat Methods 2006; 3:165-74. [PMID: 16489332 DOI: 10.1038/nmeth841] [Citation(s) in RCA: 408] [Impact Index Per Article: 22.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Bioluminescence resonance energy transfer (BRET) is a straightforward biophysical technique for studying protein-protein interactions. It requires: (1) that proteins of interest and suitable controls be labeled with either a donor or acceptor molecule, (2) placement of these labeled proteins in the desired environment for assessing their potential interaction, and (3) use of suitable detection instrumentation to monitor resultant energy transfer. There are now several possible applications, combinations of donor and acceptor molecules, potential assay environments and detection system perturbations. Therefore, this review aims to demystify and clarify the important aspects of the BRET methodology that should be considered when using this technique.
Collapse
Affiliation(s)
- Kevin D G Pfleger
- 7TM Laboratory/Laboratory for Molecular Endocrinology, Western Australian Institute for Medical Research, UWA Centre for Medical Research, University of Western Australia, Nedlands, Perth, Western Australia 6009, Australia.
| | | |
Collapse
|
33
|
Pfleger KDG, Dromey JR, Dalrymple MB, Lim EML, Thomas WG, Eidne KA. Extended bioluminescence resonance energy transfer (eBRET) for monitoring prolonged protein-protein interactions in live cells. Cell Signal 2006; 18:1664-70. [PMID: 16492395 DOI: 10.1016/j.cellsig.2006.01.004] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2005] [Accepted: 01/11/2006] [Indexed: 10/25/2022]
Abstract
Bioluminescence resonance energy transfer (BRET) is an increasingly popular technique for studying protein-protein interactions in live cells. It is particularly suitable for real-time monitoring of such interactions, however, the timescale over which assays can be carried out is currently relatively short (minutes) due to substrate instability. We present a new derivation of the BRET technology, termed 'extended BRET' (eBRET), which now enables protein-protein interactions to be monitored in real-time for many hours. This capability has significant benefits for investigating cellular function over extended timescales, as we have illustrated using the agonist-induced G-protein coupled receptor/beta-arrestin interaction. The potential for studying the modulation of such interactions by agonists, antagonists, inhibitors, dominant negative mutants and co-expressed accessory proteins is substantial. Furthermore, the advantages of eBRET have important implications for the development of high-throughput BRET screening systems, an ever-expanding area of interest for the pharmaceutical industry.
Collapse
Affiliation(s)
- Kevin D G Pfleger
- 7TM Laboratory/Laboratory for Molecular Endocrinology, Western Australian Institute for Medical Research (WAIMR) and Centre for Medical Research, University of Western Australia, Nedlands, Perth, WA 6009, Australia.
| | | | | | | | | | | |
Collapse
|
34
|
de Jong LAA, Uges DRA, Franke JP, Bischoff R. Receptor–ligand binding assays: Technologies and Applications. J Chromatogr B Analyt Technol Biomed Life Sci 2005; 829:1-25. [PMID: 16253574 DOI: 10.1016/j.jchromb.2005.10.002] [Citation(s) in RCA: 127] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2005] [Revised: 09/26/2005] [Accepted: 10/02/2005] [Indexed: 02/06/2023]
Abstract
Receptor-ligand interactions play a crucial role in biological systems and their measurement forms an important part of modern pharmaceutical development. Numerous assay formats are available that can be used to screen and quantify receptor ligands. In this review, we give an overview over both radioactive and non-radioactive assay technologies with emphasis on the latter. While radioreceptor assays are fast, easy to use and reproducible, their major disadvantage is that they are hazardous to human health, produce radioactive waste, require special laboratory conditions and are thus rather expensive on a large scale. This has led to the development of non-radioactive assays based on optical methods like fluorescence polarization, fluorescence resonance energy transfer or surface plasmon resonance. In light of their application in high-throughput screening environments, there has been an emphasis on so called "mix-and-measure" assays that do not require separation of bound from free ligand. The advent of recombinant production of receptors has contributed to the increased availability of specific assays and some aspects of the expression of recombinant receptors will be reviewed. Applications of receptor-ligand binding assays described in this review will relate to screening and the quantification of pharmaceuticals in biological matrices.
Collapse
Affiliation(s)
- Lutea A A de Jong
- Department of Analytical Biochemistry, University Centre for Pharmacy, A. Deusinglaan 1, 9713 AV Groningen, The Netherlands.
| | | | | | | |
Collapse
|
35
|
Abstract
CB1 cannabinoid receptors mediate the psychoactive effects of Delta(9)THC and actions of the endogenous cannabinoids [Howlett, A.C., Barth, F., Bonner, T.I., Cabral, G., Casellas, P., Devane, W.A., Felder, C.C., Herkenham, M., Mackie, K., Martin, B.R., Mechoulam, R., Pertwee, R.G., 2002. International Union of Pharmacology: XXVII. Classification of cannabinoid receptors. Pharmacological Reviews 54 (2) 161-202.]. CB1 receptors belong to the G protein-coupled receptor (GPCR) superfamily. In recent years, it has become apparent that many GPCRs exist as multimers--either of like or unlike receptors [Kroeger, K.M., Pfleger, K.D., Eidne, K.A., 2003. G-protein coupled receptor oligomerization in neuroendocrine pathways. Frontiers of Neuroendocrinology 24 (4) 254-278; Milligan, G., 2004. G protein-coupled receptor dimerization: function and ligand pharmacology. Molecular Pharmacology 66 (1) 1-7.]. Importantly, GPCR multimerization plays a key role in enriching the signaling repertoire of these receptors. In this review, the evidence for CB1 multimerization will be presented, the implications for cannabinoid signaling discussed, and possible future directions for this research considered.
Collapse
Affiliation(s)
- Ken Mackie
- Department of Anesthesiology, Box 356540, University of Washington, Seattle, WA 98195-6540, USA.
| |
Collapse
|
36
|
Pfleger KDG, Eidne KA. Monitoring the formation of dynamic G-protein-coupled receptor-protein complexes in living cells. Biochem J 2005; 385:625-37. [PMID: 15504107 PMCID: PMC1134737 DOI: 10.1042/bj20041361] [Citation(s) in RCA: 114] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
GPCRs (G-protein-coupled receptors) play an extremely important role in transducing extracellular signals across the cell membrane with high specificity and sensitivity. They are central to many of the body's endocrine and neurotransmitter pathways, and are consequently a major drug target. It is now clear that GPCRs interact with a range of proteins, including other GPCRs. Identifying and elucidating the function of such interactions will significantly enhance our understanding of cellular function, with the promise of new and improved pharmaceuticals. Biophysical techniques involving resonance energy transfer, namely FRET (fluorescence resonance energy transfer) and BRET (bioluminescence resonance energy transfer), now enable us to monitor the formation of dynamic GPCR-protein complexes in living cells, in real time. Their use has firmly established the concept of GPCR oligomerization, as well as demonstrating GPCR interactions with GPCR kinases, beta-arrestins, adenylate cyclase and a subunit of an inwardly rectifying K+ channel. The present review examines recent technological advances and experimental applications of FRET and BRET, discussing particularly how they have been adapted to extract an ever-increasing amount of information about the nature, specificity, stoichiometry, kinetics and agonist-dependency of GPCR-protein interactions.
Collapse
Affiliation(s)
- Kevin D G Pfleger
- Molecular Endocrinology Research Group/7TM Receptor Laboratory, Western Australian Institute for Medical Research, The University of Western Australia, Sir Charles Gairdner Hospital, Nedlands, Perth, WA 6009.
| | | |
Collapse
|