1
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Wang W. Protein-Based Tools for Studying Neuromodulation. ACS Chem Biol 2024; 19:788-797. [PMID: 38581649 PMCID: PMC11129172 DOI: 10.1021/acschembio.4c00037] [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] [Indexed: 04/08/2024]
Abstract
Neuromodulators play crucial roles in regulating neuronal activity and affecting various aspects of brain functions, including learning, memory, cognitive functions, emotional states, and pain modulation. In this Account, we describe our group's efforts in designing sensors and tools for studying neuromodulation. Our lab focuses on developing new classes of integrators that can detect neuromodulators across the whole brain while leaving a mark for further imaging analysis at high spatial resolution. Our lab also designed chemical- and light-dependent protein switches for controlling peptide activity to potentially modulate the endogenous receptors of the neuromodulatory system in order to study the causal effects of selective neuronal pathways.
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Affiliation(s)
- Wenjing Wang
- Life Sciences Institute, University of Michigan, Ann Arbor, MI, 48109, USA
- Department of Chemistry, University of Michigan, Ann Arbor, MI, 48109, USA
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2
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Masuho I, Kise R, Gainza P, Von Moo E, Li X, Tany R, Wakasugi-Masuho H, Correia BE, Martemyanov KA. Rules and mechanisms governing G protein coupling selectivity of GPCRs. Cell Rep 2023; 42:113173. [PMID: 37742189 PMCID: PMC10842385 DOI: 10.1016/j.celrep.2023.113173] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2022] [Revised: 06/21/2023] [Accepted: 09/07/2023] [Indexed: 09/26/2023] Open
Abstract
G protein-coupled receptors (GPCRs) convert extracellular stimuli into intracellular signaling by coupling to heterotrimeric G proteins of four classes: Gi/o, Gq, Gs, and G12/13. However, our understanding of the G protein selectivity of GPCRs is incomplete. Here, we quantitatively measure the enzymatic activity of GPCRs in living cells and reveal the G protein selectivity of 124 GPCRs with the exact rank order of their G protein preference. Using this information, we establish a classification of GPCRs by functional selectivity, discover the existence of a G12/13-coupled receptor, G15-coupled receptors, and a variety of subclasses for Gi/o-, Gq-, and Gs-coupled receptors, culminating in development of the predictive algorithm of G protein selectivity. We further identify the structural determinants of G protein selectivity, allowing us to synthesize non-existent GPCRs with de novo G protein selectivity and efficiently identify putative pathogenic variants.
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Affiliation(s)
- Ikuo Masuho
- Department of Neuroscience, UF Scripps Biomedical Research, Jupiter, FL 33458, USA; Pediatrics and Rare Diseases Group, Sanford Research, Sioux Falls, SD 57104, USA; Department of Pediatrics, Sanford School of Medicine, University of South Dakota, Sioux Falls, SD 57105, USA.
| | - Ryoji Kise
- Pediatrics and Rare Diseases Group, Sanford Research, Sioux Falls, SD 57104, USA
| | - Pablo Gainza
- Laboratory of Protein Design and Immunoengineering, School of Life Sciences, École Polytechnique Fédérale de Lausanne and Swiss Institute of Bioinformatics, Lausanne, Switzerland
| | - Ee Von Moo
- Department of Neuroscience, UF Scripps Biomedical Research, Jupiter, FL 33458, USA
| | - Xiaona Li
- Department of Neuroscience, UF Scripps Biomedical Research, Jupiter, FL 33458, USA
| | - Ryosuke Tany
- Pediatrics and Rare Diseases Group, Sanford Research, Sioux Falls, SD 57104, USA
| | - Hideko Wakasugi-Masuho
- Department of Neuroscience, UF Scripps Biomedical Research, Jupiter, FL 33458, USA; Pediatrics and Rare Diseases Group, Sanford Research, Sioux Falls, SD 57104, USA
| | - Bruno E Correia
- Laboratory of Protein Design and Immunoengineering, School of Life Sciences, École Polytechnique Fédérale de Lausanne and Swiss Institute of Bioinformatics, Lausanne, Switzerland
| | - Kirill A Martemyanov
- Department of Neuroscience, UF Scripps Biomedical Research, Jupiter, FL 33458, USA.
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3
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Miller RM, Sescil J, Sarcinella MC, Bailey RC, Wang W. Accessible and Generalizable in Vitro Luminescence Assay for Detecting GPCR Activation. ACS MEASUREMENT SCIENCE AU 2023; 3:337-343. [PMID: 37868356 PMCID: PMC10588934 DOI: 10.1021/acsmeasuresciau.3c00021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Revised: 06/11/2023] [Accepted: 06/20/2023] [Indexed: 10/24/2023]
Abstract
G protein-coupled receptors (GPCRs) serve critical physiological roles as the most abundant family of receptors. Here, we describe the design of a generalizable and cell lysate-based method that leverages the interaction between an agonist-activated GPCR and a conformation-specific binder to reconstitute split nanoluciferase (NanoLuc) in vitro. This tool, In vitro GPCR split NanoLuc ligand Triggered Reporter (IGNiTR), has broad applications. We have demonstrated IGNiTR's use with three Gs-coupled GPCRs, two Gi-coupled GPCRs and three classes of conformation-specific binders: nanobodies, miniG proteins, and G protein peptidomimetics. As an in vitro method, IGNiTR enables the use of synthetic G protein peptidomimetics and provides easily scalable and portable reagents for characterizing GPCRs and ligands. We tested three diverse applications of IGNiTR: (1) proof-of-concept GPCR ligand screening using dopamine receptor D1 IGNiTR; (2) detection of opioids for point-of-care testing; and (3) characterizing GPCR functionality during Nanodisc-based reconstitution processes. Due to IGNiTR's unique advantages and the convenience of its cell lysate-based format, this tool will find extensive applications in GPCR ligand detection, screening, and GPCR characterization.
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Affiliation(s)
- Ruby M. Miller
- Life Sciences
Institute, University of Michigan, Ann Arbor, Michigan 48109, United States
- Department
of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Jennifer Sescil
- Life Sciences
Institute, University of Michigan, Ann Arbor, Michigan 48109, United States
- Department
of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Marina C. Sarcinella
- Department
of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Ryan C. Bailey
- Department
of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Wenjing Wang
- Life Sciences
Institute, University of Michigan, Ann Arbor, Michigan 48109, United States
- Department
of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States
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4
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Asghar J, Latif L, Alexander SPH, Kendall DA. Development of a novel cell-based, In-Cell Western/ERK assay system for the high-throughput screening of agonists acting on the delta-opioid receptor. Front Pharmacol 2022; 13:933356. [PMID: 36225576 PMCID: PMC9549385 DOI: 10.3389/fphar.2022.933356] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2022] [Accepted: 08/08/2022] [Indexed: 11/13/2022] Open
Abstract
Background: Extracellular signal-regulated kinases (ERKs) are important signaling mediators in mammalian cells and, as a result, one of the major areas of research focus. The detection and quantification of ERK phosphorylation as an index of activation is normally conducted using immunoblotting, which does not allow high-throughput drug screening. Plate-based immunocytochemical assays provide a cheaper and relatively high-throughput alternative method for quantifying ERK phosphorylation. Here, we present optimization steps aimed to increase assay sensitivity and reduce variance and cost using the LI-COR In-Cell Western (I-CW) system in a recombinant CHO-K1 cell line, over-expressing the human delta-opioid receptor (hDOPr) as a model.Methods: Cells cultured in 96-well microassay plates were stimulated with three standard/selective DOPr agonists (SNC80, ADL5859, and DADLE) and a novel selective DOPr agonist (PN6047) to elicit a phospho-ERK response as an index of activation. A number of experimental conditions were investigated during the assay development.Key results: Preliminary experiments revealed a clearly visible edge-effect which significantly increased assay variance across the plate and which was reduced by pre-incubation for 30 min at room temperature. ERK phosphorylation was detectable as early as 1 min after agonist addition, with a distinct peak at 3–5 min. Optimization of the cell seeding densities showed that 25,000 cells per well have the lowest basal phospho-ERK response and an optimal agonist ERK1/2 signal. Pre-incubation with apyrase (an ATPase) did not reduce the basal or agonist responses. All agonists produced concentration-dependent increases in phospho-ERK activation, and pertussis toxin was able to attenuate these ERK responses. Naltrindole, which is a selective DOPr antagonist, was able to antagonize the DOPr-mediated ERK activation of the ligands.Conclusion: We have developed an optimization protocol and highlighted a number of considerations when performing this high-throughput fluorescence immunocytochemical (ICC) assay measuring ERK phosphorylation in the human DOPr. The optimized protocol was found to be a more conducive option for the screening of delta agonists. This provides a basis for additional assay development to investigate opioid pharmacology. This protocol should be widely applicable for measuring ERK phosphorylation in any cell line and investigating other protein targets in GPCR drug discovery.
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Affiliation(s)
- Junaid Asghar
- Faculty of Pharmacy, Gomal University, Dera Ismail Khan, Pakistan
- School of Life Sciences, Faculty of Medicine and Health Sciences, Medical School, QMC, University of Nottingham, Nottingham, United Kingdom
- *Correspondence: Junaid Asghar,
| | - Liaque Latif
- School of Life Sciences, Faculty of Medicine and Health Sciences, Medical School, QMC, University of Nottingham, Nottingham, United Kingdom
| | - Stephen P. H. Alexander
- School of Life Sciences, Faculty of Medicine and Health Sciences, Medical School, QMC, University of Nottingham, Nottingham, United Kingdom
| | - David A. Kendall
- School of Life Sciences, Faculty of Medicine and Health Sciences, Medical School, QMC, University of Nottingham, Nottingham, United Kingdom
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5
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Yang X, Zhang M, Lu Z, Zhi L, Xue H, Liu T, Liu M, Cui L, Liu Z, He P, Liu Y, Zhang Y. Novel Small Molecule Glucagon-Like Peptide-1 Receptor Agonist S6 Stimulates Insulin Secretion From Rat Islets. Front Pharmacol 2021; 12:664802. [PMID: 33995091 PMCID: PMC8116734 DOI: 10.3389/fphar.2021.664802] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2021] [Accepted: 04/12/2021] [Indexed: 12/03/2022] Open
Abstract
Glucagon-like peptide-1 receptor (GLP-1R) agonist-based therapeutics for type 2 diabetes mellitus have attracted worldwide attention. However, there are challenges in the development of small molecule GLP-1R agonists owing to the complexity of ligand recognition and signal induction mechanisms. Here, we attained S6 using virtual screening and fluorescent imaging plate reader (FLIPR)-based calcium assays. The purpose of this study was to identify and characterize S6, a novel small molecule GLP-1R agonist. Data from cellular thermal shift assay (CETSA) and Bio-Layer Interferometry (BLI) indicated that S6 could bind potently with GLP-1R. Radioimmunoassay data showed that S6 potentiated insulin secretion in a glucose-dependent manner and the insulinotropic effect was mediated by GLP-1R. Calcium imaging techniques suggested that S6 elevated the intracellular calcium concentration [(Ca2+)i] by activating GLP-1R. In patch-clamp experiments, we demonstrated that S6 inhibited voltage-dependent K+ (Kv) channels in a GLP-1R-dependent fashion. Besides, S6 significantly prolonged action potential duration but had no effect on voltage-dependent Ca2+ channels. In summary, these findings indicate that S6 stimulates glucose-dependent insulin secretion mainly by acting on GLP-1R, inhibiting Kv channels, increasing (Ca2+)i. This study will provide direction for the screening and development of novel small-molecule agents targeting GLP-1R in the future.
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Affiliation(s)
- Xiaohua Yang
- Department of Pharmacology, Shanxi Medical University, Taiyuan, China
| | - Min Zhang
- Department of Pharmacy, Shanxi Medical University, Taiyuan, China
| | - Zhihong Lu
- Department of Pharmacology, Shanxi Medical University, Taiyuan, China
| | - Linping Zhi
- Department of Pharmacology, Shanxi Medical University, Taiyuan, China
| | - Huan Xue
- Department of Pharmacology, Shanxi Medical University, Taiyuan, China.,Key Laboratory of Cellular Physiology, Ministry of Education, Shanxi Medical University, Taiyuan, China
| | - Tao Liu
- Department of Pharmacology, Shanxi Medical University, Taiyuan, China
| | - Mengmeng Liu
- Department of Pharmacology, Shanxi Medical University, Taiyuan, China
| | - Lijuan Cui
- Department of Pharmacology, Shanxi Medical University, Taiyuan, China.,Key Laboratory of Cellular Physiology, Ministry of Education, Shanxi Medical University, Taiyuan, China
| | - Zhihong Liu
- Department of Pharmacology, Shanxi Medical University, Taiyuan, China
| | - Peifeng He
- School of Management, Shanxi Medical University, Taiyuan, China
| | - Yunfeng Liu
- Department of Endocrinology, First Hospital of Shanxi Medical University, Shanxi Medical University, Taiyuan, China
| | - Yi Zhang
- Department of Pharmacology, Shanxi Medical University, Taiyuan, China.,Key Laboratory of Cellular Physiology, Ministry of Education, Shanxi Medical University, Taiyuan, China
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6
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Zhao XF. G protein-coupled receptors function as cell membrane receptors for the steroid hormone 20-hydroxyecdysone. Cell Commun Signal 2020; 18:146. [PMID: 32907599 PMCID: PMC7488307 DOI: 10.1186/s12964-020-00620-y] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2020] [Accepted: 06/27/2020] [Indexed: 12/16/2022] Open
Abstract
Abstract G protein-coupled receptors (GPCRs) are cell membrane receptors for various ligands. Recent studies have suggested that GPCRs transmit animal steroid hormone signals. Certain GPCRs have been shown to bind steroid hormones, for example, G protein-coupled estrogen receptor 1 (GPER1) binds estrogen in humans, and Drosophila dopamine/ecdysteroid receptor (DopEcR) binds the molting hormone 20-hydroxyecdysone (20E) in insects. This review summarizes the research progress on GPCRs as animal steroid hormone cell membrane receptors, including the nuclear and cell membrane receptors of steroid hormones in mammals and insects, the 20E signaling cascade via GPCRs, termination of 20E signaling, and the relationship between genomic action and the nongenomic action of 20E. Studies indicate that 20E induces a signal via GPCRs to regulate rapid cellular responses, including rapid Ca2+ release from the endoplasmic reticulum and influx from the extracellular medium, as well as rapid protein phosphorylation and subcellular translocation. 20E via the GPCR/Ca2+/PKC/signaling axis and the GPCR/cAMP/PKA-signaling axis regulates gene transcription by adjusting transcription complex formation and DNA binding activity. GPCRs can bind 20E in the cell membrane and after being isolated, suggesting GPCRs as cell membrane receptors of 20E. This review deepens our understanding of GPCRs as steroid hormone cell membrane receptors and the GPCR-mediated signaling pathway of 20E (20E-GPCR pathway), which will promote further study of steroid hormone signaling via GPCRs, and presents GPCRs as targets to explore new pharmaceutical materials to treat steroid hormone-related diseases or control pest insects. Video abstract
Graphical abstract ![]()
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Affiliation(s)
- Xiao-Fan Zhao
- Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology, School of Life Sciences, Shandong University, Qingdao, 266237, China.
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7
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Wu L, Zhang W, Qiu X, Wang C, Liu Y, Wang Z, Yu Y, Ye RD, Zhang Y. Identification of Alkaloids from Corydalis yanhusuo W. T. Wang as Dopamine D₁ Receptor Antagonists by Using CRE-Luciferase Reporter Gene Assay. Molecules 2018; 23:E2585. [PMID: 30308941 PMCID: PMC6222624 DOI: 10.3390/molecules23102585] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2018] [Revised: 08/02/2018] [Accepted: 08/12/2018] [Indexed: 02/06/2023] Open
Abstract
Corydalis yanhusuo W. T. Wang (C. yanhusuo) has been traditionally used for drug addiction and pain relief in China. In our previous study, we showed that the extract of C. yanhusuo blocks dopamine receptors, demonstrating that its pharmacological activities are mostly due to the antagonistic effects of some of its components at dopamine receptors. As part of our ongoing project on C. yanhusuo, the aim of the present study is to establish a high-throughput and low-cost screening assay system and test the abilities of the isolated alkaloids from C. yanhusuo to inhibit dopamine-induced dopamine D₁ receptor activity. By using our established cyclic adenosine monophosphate (cAMP)-response element (CRE)-luciferase reporter gene assay system, we identified eight alkaloids from C. yanhusuo with D₁ receptor antagonistic activities. We next validated the activities of these compounds using fluorometric imaging plate reader (FLIPR) assay by measuring the intracellular Ca2+ change. Six out of eight compounds, including tetrahydropalmatine, corydaline, 13-methyldehydrocorydalmine, dehydrocorybubine, dehydrocorydaline, and columbamine, can be confirmed for their inhibitory activities. The dopamine-receptor-antagonistic effects of four compounds, including 13-methyldehydrocorydalmine, dehydrocorydaline, columbamine, and corydaline, are reported for the first time. The present study provides an important pharmacological basis to support the traditional use of C. yanhusuo in China.
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Affiliation(s)
- Lehao Wu
- School of Pharmacy, Shanghai Jiao Tong University, Shanghai 200240, China.
| | - Weiyue Zhang
- School of Pharmacy, Shanghai Jiao Tong University, Shanghai 200240, China.
| | - Xin Qiu
- School of Pharmacy, Shanghai Jiao Tong University, Shanghai 200240, China.
| | - Chaoran Wang
- Key Lab of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China.
| | - Yanfang Liu
- Key Lab of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China.
| | - Zhiwei Wang
- DICP-CMC Innovation Institute of Medicine, Taizhou 225300, China.
| | - Yang Yu
- School of Pharmacy, Shanghai Jiao Tong University, Shanghai 200240, China.
| | - Richard D Ye
- School of Pharmacy, Shanghai Jiao Tong University, Shanghai 200240, China.
- State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macau 999078, SAR, China.
| | - Yan Zhang
- School of Pharmacy, Shanghai Jiao Tong University, Shanghai 200240, China.
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8
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Yang H, Kim D, Kim J, Moon D, Song HS, Lee M, Hong S, Park TH. Nanodisc-Based Bioelectronic Nose Using Olfactory Receptor Produced in Escherichia coli for the Assessment of the Death-Associated Odor Cadaverine. ACS NANO 2017; 11:11847-11855. [PMID: 29121467 DOI: 10.1021/acsnano.7b04992] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Cadaverine (CV), a death-associated odor, is an important target molecule for various sensor applications, including the evaluation of food spoilage. In this study, we developed an oriented nanodisc (ND)-functionalized bioelectronic nose (ONBN), based on carbon nanotube transistors and nanodiscs embedded with an olfactory receptor produced in Escherichia coli (E. coli) for detection of CV. To fabricate ONBN devices, a trace-amine-associated receptor 13c (TAAR13c) binding to CV was produced in E. coli, purified, reconstituted into NDs, and assembled, in the desired orientation, onto a carbon- nanotube-based field-effect transistor with floating electrodes. The ONBN showed high performance in terms of sensitivity and selectivity. Moreover, the ONBN was used to measure CV in diverse real-food samples for the determination of food freshness. These results indicate ONBN devices can be utilized to evaluate the quality of food samples quantitatively, which should enable versatile practical applications such as food safety and preservative development. Moreover, the ONBN could provide a useful tool for detection of corpses, which could be practically used in disaster responses.
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Affiliation(s)
- Heehong Yang
- School of Chemical and Biological Engineering, Seoul National University , Seoul 08826, Republic of Korea
| | - Daesan Kim
- Department of Biophysics and Chemical Biology, Seoul National University , Seoul 08826, Republic of Korea
| | - Jeongsu Kim
- Department of Physics and Astronomy and Institute of Applied Physics, Seoul National University , Seoul 08826, Republic of Korea
| | - Dongseok Moon
- School of Chemical and Biological Engineering, Seoul National University , Seoul 08826, Republic of Korea
| | - Hyun Seok Song
- Division of Bioconvergence Analysis, Korea Basic Science Institute (KBSI) , Daejeon 34133, Republic of Korea
- Center for Convergent Research of Emerging Virus Infection, Korea Research Institute of Chemical Technology , Daejeon 34114, Republic of Korea
| | - Minju Lee
- Department of Physics and Astronomy and Institute of Applied Physics, Seoul National University , Seoul 08826, Republic of Korea
| | - Seunghun Hong
- Department of Physics and Astronomy and Institute of Applied Physics, Seoul National University , Seoul 08826, Republic of Korea
| | - Tai Hyun Park
- School of Chemical and Biological Engineering, Seoul National University , Seoul 08826, Republic of Korea
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9
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Park SJ, Yang H, Lee SH, Song HS, Park CS, Bae J, Kwon OS, Park TH, Jang J. Dopamine Receptor D1 Agonism and Antagonism Using a Field-Effect Transistor Assay. ACS NANO 2017; 11:5950-5959. [PMID: 28558184 DOI: 10.1021/acsnano.7b01722] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
The field-effect transistor (FET) has been used in the development of diagnostic tools for several decades, leading to high-performance biosensors. Therefore, the FET platform can provide the foundation for the next generation of analytical methods. A major role of G-protein-coupled receptors (GPCRs) is in the transfer of external signals into the cell and promoting human body functions; thus, their principle application is in the screening of new drugs. The research community uses efficient systems to screen potential GPCR drugs; nevertheless, the need to develop GPCR-conjugated analytical devices remains for next-generation new drug screening. In this study, we proposed an approach for studying receptor agonism and antagonism by combining the roles of FETs and GPCRs in a dopamine receptor D1 (DRD1)-conjugated FET system, which is a suitable substitute for conventional cell-based receptor assays. DRD1 was reconstituted and purified to mimic native binding pockets that have highly discriminative interactions with DRD1 agonists/antagonists. The real-time responses from the DRD1-nanohybrid FET were highly sensitive and selective for dopamine agonists/antagonists, and their maximal response levels were clearly different depending on their DRD1 affinities. Moreover, the equilibrium constants (K) were estimated by fitting the response levels. Each K value indicates the variation in the affinity between DRD1 and the agonists/antagonists; a greater K value corresponds to a stronger DRD1 affinity in agonism, whereas a lower K value in antagonism indicates a stronger dopamine-blocking effect.
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Affiliation(s)
- Seon Joo Park
- Harzards Monitoring Bionano Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB) , Daejeon 34141, Republic of Korea
- School of Chemical and Biological Engineering, Seoul National University , Seoul 08826, Republic of Korea
| | - Heehong Yang
- School of Chemical and Biological Engineering, Seoul National University , Seoul 08826, Republic of Korea
| | - Seung Hwan Lee
- School of Chemical and Biological Engineering, Seoul National University , Seoul 08826, Republic of Korea
| | - Hyun Seok Song
- Division of Bioconvergence Analysis, Korea Basic Science Institute (KBSI) , Daejeon 34133, Republic of Korea
- Center for Convergent Research of Emerging Virus Infection, Korea Research Institute of Chemical Technology , Daejeon 34114, Republic of Korea
| | - Chul Soon Park
- Harzards Monitoring Bionano Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB) , Daejeon 34141, Republic of Korea
| | - Joonwon Bae
- Department of Applied Chemistry, Dongduk Women's University , Seoul 02748, Republic of Korea
| | - Oh Seok Kwon
- Harzards Monitoring Bionano Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB) , Daejeon 34141, Republic of Korea
| | - Tai Hyun Park
- School of Chemical and Biological Engineering, Seoul National University , Seoul 08826, Republic of Korea
| | - Jyongsik Jang
- School of Chemical and Biological Engineering, Seoul National University , Seoul 08826, Republic of Korea
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10
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Brust A, Croker DE, Colless B, Ragnarsson L, Andersson Å, Jain K, Garcia-Caraballo S, Castro J, Brierley SM, Alewood PF, Lewis RJ. Conopeptide-Derived κ-Opioid Agonists (Conorphins): Potent, Selective, and Metabolic Stable Dynorphin A Mimetics with Antinociceptive Properties. J Med Chem 2016; 59:2381-95. [PMID: 26859603 DOI: 10.1021/acs.jmedchem.5b00911] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Opioid receptor screening of a conopeptide library led to a novel selective κ-opioid agonist peptide (conorphin T). Intensive medicinal chemistry, guided by potency, selectivity, and stability assays generated a pharmacophore model supporting rational design of highly potent and selective κ-opioid receptor (KOR) agonists (conorphins) with exceptional plasma stability. Conorphins are defined by a hydrophobic benzoprolyl moiety, a double arginine sequence, a spacer amino acid followed by a hydrophobic residue and a C-terminal vicinal disulfide moiety. The pharmacophore model was supported by computational docking studies, revealing receptor-ligand interactions similar to KOR agonist dynorphin A (1-8). A conorphin agonist inhibited colonic nociceptors in a mouse tissue model of chronic visceral hypersensitivity, suggesting the potential of KOR agonists for the treatment of chronic abdominal pain. This new conorphine KOR agonist class and pharmacophore model provide opportunities for future rational drug development and probes for exploring the role of the κ-opioid receptor.
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Affiliation(s)
- Andreas Brust
- Xenome Limited , Brisbane, Queensland 4068, Australia.,Institute for Molecular Biosciences, The University of Queensland , Brisbane, Queensland, 4072, Australia
| | - Daniel E Croker
- Xenome Limited , Brisbane, Queensland 4068, Australia.,Institute for Molecular Biosciences, The University of Queensland , Brisbane, Queensland, 4072, Australia
| | - Barbara Colless
- Xenome Limited , Brisbane, Queensland 4068, Australia.,Institute for Molecular Biosciences, The University of Queensland , Brisbane, Queensland, 4072, Australia
| | - Lotten Ragnarsson
- Xenome Limited , Brisbane, Queensland 4068, Australia.,Institute for Molecular Biosciences, The University of Queensland , Brisbane, Queensland, 4072, Australia
| | - Åsa Andersson
- Xenome Limited , Brisbane, Queensland 4068, Australia.,Institute for Molecular Biosciences, The University of Queensland , Brisbane, Queensland, 4072, Australia
| | - Kapil Jain
- Institute for Molecular Biosciences, The University of Queensland , Brisbane, Queensland, 4072, Australia
| | - Sonia Garcia-Caraballo
- Visceral Pain Group, Centre for Nutrition and Gastrointestinal Disease, Discipline of Medicine, The University of Adelaide, South Australian Health and Medical Research Institute, SAHMRI , Adelaide, SA 5000, Australia
| | - Joel Castro
- Visceral Pain Group, Centre for Nutrition and Gastrointestinal Disease, Discipline of Medicine, The University of Adelaide, South Australian Health and Medical Research Institute, SAHMRI , Adelaide, SA 5000, Australia
| | - Stuart M Brierley
- Visceral Pain Group, Centre for Nutrition and Gastrointestinal Disease, Discipline of Medicine, The University of Adelaide, South Australian Health and Medical Research Institute, SAHMRI , Adelaide, SA 5000, Australia
| | - Paul F Alewood
- Institute for Molecular Biosciences, The University of Queensland , Brisbane, Queensland, 4072, Australia
| | - Richard J Lewis
- Xenome Limited , Brisbane, Queensland 4068, Australia.,Institute for Molecular Biosciences, The University of Queensland , Brisbane, Queensland, 4072, Australia
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11
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Kaserer T, Lantero A, Schmidhammer H, Spetea M, Schuster D. μ Opioid receptor: novel antagonists and structural modeling. Sci Rep 2016; 6:21548. [PMID: 26888328 PMCID: PMC4757823 DOI: 10.1038/srep21548] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2015] [Accepted: 01/27/2016] [Indexed: 11/08/2022] Open
Abstract
The μ opioid receptor (MOR) is a prominent member of the G protein-coupled receptor family and the molecular target of morphine and other opioid drugs. Despite the long tradition of MOR-targeting drugs, still little is known about the ligand-receptor interactions and structure-function relationships underlying the distinct biological effects upon receptor activation or inhibition. With the resolved crystal structure of the β-funaltrexamine-MOR complex, we aimed at the discovery of novel agonists and antagonists using virtual screening tools, i.e. docking, pharmacophore- and shape-based modeling. We suggest important molecular interactions, which active molecules share and distinguish agonists and antagonists. These results allowed for the generation of theoretically validated in silico workflows that were employed for prospective virtual screening. Out of 18 virtual hits evaluated in in vitro pharmacological assays, three displayed antagonist activity and the most active compound significantly inhibited morphine-induced antinociception. The new identified chemotypes hold promise for further development into neurochemical tools for studying the MOR or as potential therapeutic lead candidates.
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Affiliation(s)
- Teresa Kaserer
- Computer-Aided Molecular Design Group, Department of Pharmaceutical Chemistry, Institute of Pharmacy and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innrain 80-82, 6020 Innsbruck, Austria
| | - Aquilino Lantero
- Opioid Research Group, Department of Pharmaceutical Chemistry, Institute of Pharmacy and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innrain 80-82, 6020 Innsbruck, Austria
| | - Helmut Schmidhammer
- Opioid Research Group, Department of Pharmaceutical Chemistry, Institute of Pharmacy and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innrain 80-82, 6020 Innsbruck, Austria
| | - Mariana Spetea
- Opioid Research Group, Department of Pharmaceutical Chemistry, Institute of Pharmacy and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innrain 80-82, 6020 Innsbruck, Austria
| | - Daniela Schuster
- Computer-Aided Molecular Design Group, Department of Pharmaceutical Chemistry, Institute of Pharmacy and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innrain 80-82, 6020 Innsbruck, Austria
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12
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Heusler P, Tardif S, Cussac D. Agonist stimulation at human μ opioid receptors in a [(35)S]GTPγS incorporation assay: observation of "bell-shaped" concentration-response relationships under conditions of strong receptor G protein coupling. J Recept Signal Transduct Res 2015; 36:158-66. [PMID: 26466637 DOI: 10.3109/10799893.2015.1069845] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
CONTEXT The appearance of "bell"- (or "inverted U"-) shaped agonist concentration-response curves (CRCs) in in vitro pharmacological experiments is a frequently observed but poorly communicated phenomenon. In the context of G protein coupled receptor research, it is commonly attributed to the recruitment of secondary targets or to desensitization or feedback processes, but the concrete background of these observations often remains intriguing. OBJECTIVE Here, we addressed the subject of bell-shaped agonist CRCs at the µ opioid receptor (µOR) by testing the impact of experimental conditions favoring G protein coupling. METHODS G protein activation by recombinant human µORs heterologously expressed in CHO cells was assessed in [(35)S]GTPγS binding assays using the opioid ligands DAMGO, morphine, fentanyl and naloxone. Experimental conditions were varied by changing the NaCl (10-300 mM) and the GDP concentration (0.3-30 µM). RESULTS Both the sodium and the GDP concentration were inversely related to G protein coupling, as evident by an increase in basal [(35)S]GTPγS incorporation at low sodium and low GDP levels and by the concomitant appearance of the partial agonist activity of the µOR antagonist, naloxone. Bell-shaped CRCs were observed for the efficacious agonists DAMGO, fentanyl and morphine, and this phenomenon was promoted by low sodium as well as by low GDP concentrations. CONCLUSION µOR agonist CRCs show a non-monotonic behavior with a decline of maximal stimulation under conditions of strong receptor-G protein coupling, and this behavior is visible at the level of G protein activation itself.
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Affiliation(s)
- Peter Heusler
- a Department of Cellular and Molecular Biology , Pierre Fabre Research Center , Castres Cedex , France
| | - Stéphanie Tardif
- a Department of Cellular and Molecular Biology , Pierre Fabre Research Center , Castres Cedex , France
| | - Didier Cussac
- a Department of Cellular and Molecular Biology , Pierre Fabre Research Center , Castres Cedex , France
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13
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Milić D, Veprintsev DB. Large-scale production and protein engineering of G protein-coupled receptors for structural studies. Front Pharmacol 2015; 6:66. [PMID: 25873898 PMCID: PMC4379943 DOI: 10.3389/fphar.2015.00066] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2015] [Accepted: 03/13/2015] [Indexed: 01/26/2023] Open
Abstract
Structural studies of G protein-coupled receptors (GPCRs) gave insights into molecular mechanisms of their action and contributed significantly to molecular pharmacology. This is primarily due to technical advances in protein engineering, production and crystallization of these important receptor targets. On the other hand, NMR spectroscopy of GPCRs, which can provide information about their dynamics, still remains challenging due to difficulties in preparation of isotopically labeled receptors and their low long-term stabilities. In this review, we discuss methods used for expression and purification of GPCRs for crystallographic and NMR studies. We also summarize protein engineering methods that played a crucial role in obtaining GPCR crystal structures.
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Affiliation(s)
- Dalibor Milić
- Laboratory of Biomolecular Research, Paul Scherrer Institut, Villigen Switzerland
| | - Dmitry B Veprintsev
- Laboratory of Biomolecular Research, Paul Scherrer Institut, Villigen Switzerland ; Department of Biology, Eidgenössische Technische Hochschule Zürich, Zürich Switzerland
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14
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McNeely PM, Naranjo AN, Robinson AS. Structure-function studies with G protein-coupled receptors as a paradigm for improving drug discovery and development of therapeutics. Biotechnol J 2013; 7:1451-61. [PMID: 23213015 DOI: 10.1002/biot.201200076] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2012] [Revised: 10/07/2012] [Accepted: 10/10/2012] [Indexed: 12/21/2022]
Abstract
There are a great variety of human membrane proteins, and these currently form the largest group of targets for marketed drugs. Despite the advances in drug design, however, promiscuity between drug molecules and targets often leads to undesired signaling effects, which result in unintended side effects. In this review, one family of membrane proteins - the G protein-coupled receptors (GPCRs) - is used as a model to review experimental techniques that may be used to examine the activity of membrane proteins. As these receptors are highly relevant to healthy human physiology and represent the largest family of drug targets, they represent an excellent model for membrane proteins in general. We also review experimental evidence that suggests there may be multiple ways to target a GPCR - and by extension, membrane proteins - to more effectively target unhealthy phenotypes while reducing the occurrence and severity of side effects.
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Affiliation(s)
- Patrick M McNeely
- Department of Chemical and Biomolecular Engineering, University of Delaware, Newark, DE, USA
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15
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Durán-Prado M, Gahete MD, Delgado-Niebla E, Martínez-Fuentes AJ, Vázquez-Martínez R, García-Navarro S, Gracia-Navarro F, Malagon MM, Luque RM, Castaño JP. Truncated variants of pig somatostatin receptor subtype 5 (sst5) act as dominant-negative modulators for sst2-mediated signaling. Am J Physiol Endocrinol Metab 2012; 303:E1325-34. [PMID: 23032684 DOI: 10.1152/ajpendo.00445.2012] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Somatostatin (SST) and its related peptide cortistatin (CORT) exert their multiple actions through binding to the SST receptor (sst) family, generally considered to comprise five G protein-coupled receptors with seven transmembrane domains (TMD), named sst1-sst5, plus a splice sst2B variant. However, we recently discovered that human and rodent sst5 gene expression also generates, through noncanonical alternative splicing, novel truncated albeit functional sst5 variants with less than seven TMD. Here, we cloned and characterized for the first time the porcine wild-type sst5 (psst5, full-length) and identified two novel truncated psst5 variants with six and three TMD, thus termed psst5TMD6 and psst5TMD3, respectively. In line with that observed in human and rodent truncated sst5 variants, psst5TMD6 and psst5TMD3 are functional (e.g., activate calcium signaling), selectively respond to SST and CORT, respectively, and exhibit specific tissue expression profiles that differ from full-length psst5 and often overlaps with psst2 expression. Moreover, fluorescence resonance energy transfer analysis shows that psst5 truncated variants physically interact with psst2, thereby altering their localization at the plasma membrane and specifically disrupting the cellular response to SST and/or CORT. These results represent the first characterization of a key porcine SST receptor, psst5, and, together with our previous results, provide strong evidence that alternative splicing-derived, truncated sst5 variants with distinct functional capacities exist in the mammalian lineage, where they can act as dominant-negative receptors, by interacting directly with long, seven TMD variants, potentially contributing to modulate normal and pathological SST and CORT signaling.
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Affiliation(s)
- Mario Durán-Prado
- Department of Cell Biology, Physiology, and Immunology, University of Córdoba, Reina Sofía University Hospital, Instituto Maimónides de Investigación Biomédica de Córdoba, and CIBER Fisiopatología de la Obesidad y Nutrición, Córdoba, Spain
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16
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Hara K, Shigemori T, Kuroda K, Ueda M. Membrane-displayed somatostatin activates somatostatin receptor subtype-2 heterologously produced in Saccharomyces cerevisiae. AMB Express 2012. [PMID: 23193953 PMCID: PMC3558460 DOI: 10.1186/2191-0855-2-63] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
The G-protein-coupled receptor (GPCR) superfamily, which includes somatostatin receptors (SSTRs), is one of the most important drug targets in the pharmaceutical industry. The yeast Saccharomyces cerevisiae is an attractive host for the ligand screening of human GPCRs. Here, we demonstrate the utility of the technology that was developed for displaying peptide ligands on yeast plasma membrane, termed "PepDisplay", which triggers signal transduction upon GPCR activation. A yeast strain that heterologously produced human somatostatin receptor subtype-2 (SSTR2) and chimeric Gα protein was constructed along with membrane-displayed somatostatin; somatostatin was displayed on the yeast plasma membrane by linking it to the anchoring domain of the glycosylphosphatidylinositol anchored plasma membrane protein Yps1p. We demonstrate that the somatostatin displayed on the plasma membrane successfully activated human SSTR2 in S. cerevisiae. The methodology presented here provides a new platform for identifying novel peptide ligands for both liganded and orphan mammalian GPCRs.
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17
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Martins SAM, Trabuco JRC, Monteiro GA, Chu V, Conde JP, Prazeres DMF. Towards the miniaturization of GPCR-based live-cell screening assays. Trends Biotechnol 2012; 30:566-74. [PMID: 22921755 DOI: 10.1016/j.tibtech.2012.07.004] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2012] [Revised: 07/23/2012] [Accepted: 07/24/2012] [Indexed: 01/13/2023]
Abstract
G protein-coupled receptors (GPCRs) play a key role in many physiological or disease-related processes and for this reason are favorite targets of the pharmaceutical industry. Although ~30% of marketed drugs target GPCRs, their potential remains largely untapped. The discovery of new leads calls for the screening of thousands of compounds with high-throughput cell-based assays. Although microtiter plate-based high-throughput screening platforms are well established, microarray and microfluidic technologies hold potential for miniaturization, automation, and biosensor integration that may well redefine the format of GPCR screening assays. This paper reviews the latest research efforts directed to bringing microarray and microfluidic technologies into the realm of GPCR-based, live-cell screening assays.
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Affiliation(s)
- Sofia A M Martins
- IBB-Institute for Biotechnology and Bioengineering, Centre for Biological and Chemical Engineering, Department of Bioengineering, Instituto Superior Técnico, Technical University of Lisbon, 1049-001 Lisbon, Portugal
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18
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Morrow JK, Zhang S. Computational prediction of protein hot spot residues. Curr Pharm Des 2012; 18:1255-65. [PMID: 22316154 DOI: 10.2174/138161212799436412] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2011] [Accepted: 12/06/2011] [Indexed: 11/22/2022]
Abstract
Most biological processes involve multiple proteins interacting with each other. It has been recently discovered that certain residues in these protein-protein interactions, which are called hot spots, contribute more significantly to binding affinity than others. Hot spot residues have unique and diverse energetic properties that make them challenging yet important targets in the modulation of protein-protein complexes. Design of therapeutic agents that interact with hot spot residues has proven to be a valid methodology in disrupting unwanted protein-protein interactions. Using biological methods to determine which residues are hot spots can be costly and time consuming. Recent advances in computational approaches to predict hot spots have incorporated a myriad of features, and have shown increasing predictive successes. Here we review the state of knowledge around protein-protein interactions, hot spots, and give an overview of multiple in silico prediction techniques of hot spot residues.
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Affiliation(s)
- John Kenneth Morrow
- Department of Experimental Therapeutics, The University of Texas M.D. Anderson Cancer Center, Houston, Texas 77054, USA
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19
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Chen L, Jin L, Zhou N. An update of novel screening methods for GPCR in drug discovery. Expert Opin Drug Discov 2012; 7:791-806. [DOI: 10.1517/17460441.2012.699036] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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20
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Trinquet E, Bouhelal R, Dietz M. Monitoring Gq-coupled receptor response through inositol phosphate quantification with the IP-One assay. Expert Opin Drug Discov 2011; 6:981-94. [DOI: 10.1517/17460441.2011.608658] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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21
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Yano Y, Matsuzaki K. Fluorescence ratiometric detection of ligand-induced receptor internalization using extracellular coiled-coil tag-probe labeling. FEBS Lett 2011; 585:2385-8. [PMID: 21708150 DOI: 10.1016/j.febslet.2011.06.012] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2011] [Accepted: 06/10/2011] [Indexed: 10/18/2022]
Abstract
We report a new method for the detection of ligand-induced receptor internalization by fluorescence ratiometric imaging of pH in endosomes in combination with a recently developed posttranslational labeling system based on the formation of a heterodimeric coiled-coil structure. The N-terminus of the β2-adrenergic receptor expressed on the cell surface was doubly labeled with pH-sensitive fluorescein and pH-insensitive tetramethylrhodamine. A significant increase in the tetramethylrhodamine-to-fluorescein fluorescence intensity ratio was observed after incubation with agonists in a concentration-dependent manner. This simple and accurate method of detecting the agonistic activity of receptors will be useful for high-throughput screening of drug candidates.
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Affiliation(s)
- Yoshiaki Yano
- Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyo-ku, Kyoto, Japan
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22
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Wang Y, Kong Y, Shei GJ, Kang L, Cvijic ME. Development of a cyclic adenosine monophosphate assay for Gi-coupled G protein-coupled receptors by utilizing the endogenous calcitonin activity in Chinese hamster ovary cells. Assay Drug Dev Technol 2011; 9:522-31. [PMID: 21561374 DOI: 10.1089/adt.2010.0361] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Activation of G(i)-coupled G protein-coupled receptor (GPCRs) by their ligands leads to inhibition of adenylyl cyclase (AC) and reduction of cyclic adenosine monophosphate (cAMP) levels in cells. The traditional cAMP assay for G(i)-coupled GPCRs commonly uses forskolin, a nonspecific AC activator, to increase the basal cAMP level in cells to create an assay window for ligand detection. However, there is still a need to develop a nonforskolin-based cAMP assay because of the challenges inherent in titrating the concentration of forskolin to achieve a reliable assay window, along with issues related to the cAMP-independent effects of forskolin. Herein, we describe such an assay by utilizing the endogenous activity of the calcitonin receptor in Chinese hamster ovary (CHO) cells. The calcitonin receptor is a G(s)-coupled GPCR that, when activated by calcitonin, leads to the stimulation of AC and increases cAMP in cells. Thus, we use calcitonin, instead of forskolin, to increase the basal cAMP level in CHO cells to achieve an assay window. We demonstrated that calcitonin peptides robustly increased cAMP accumulation in several CHO cell lines stably expressing well-known G(i)-coupled GPCRs, such as the Dopamine D2 receptor, the Opioid μ receptor, or the Cannabinoid receptor-1. Agonists of these G(i)-coupled GPCRs attenuated calcitonin-induced cAMP production in their receptor stable cell lines. On the other hand, antagonists and/or inverse agonists blocked the effects of their agonists on calcitonin-induced cAMP production. This calcitonin-based cAMP assay has been demonstrated to be sensitive and robust and exhibited acceptable assay windows (signal/noise ratio) and, thus, can be applied to screen for agonists and antagonists/inverse agonists of G(i)-coupled GPCRs in high-throughput screening formats.
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Affiliation(s)
- Yuren Wang
- Metabolic Disease Research, Bristol-Myers Squibb Company, 311 Pennington-Rocky Hill Road, Pennington, NJ 08534, USA.
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Allen JA, Roth BL. Strategies to discover unexpected targets for drugs active at G protein-coupled receptors. Annu Rev Pharmacol Toxicol 2011; 51:117-44. [PMID: 20868273 DOI: 10.1146/annurev-pharmtox-010510-100553] [Citation(s) in RCA: 166] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
G protein-coupled receptors (GPCRs) are an evolutionarily conserved family of signaling molecules comprising approximately 2% of the human genome; this receptor family remains a central focus in basic pharmacology studies and drug discovery efforts. Detailed studies of drug action at GPCRs over the past decade have revealed existing and novel ligands that exhibit polypharmacology-that is, drugs with activity at more than one receptor target for which they were designed. These "off-target" drug actions can be a liability that causes adverse side effects; however, in several cases, drugs with less selectivity demonstrate better clinical efficacy. Here we review physical screening and cheminformatic approaches that define drug activity at the GPCR receptorome. In many cases, such profiling has revealed unexpected targets that explain therapeutic actions as well as off-targets underlying drug side effects. Such drug-receptor profiling has also provided new insights into mechanisms of action of existing drugs and has suggested directions for future drug development.
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Affiliation(s)
- John A Allen
- Department of Pharmacology, University of North Carolina, Chapel Hill, 27599, USA
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Cullen M, Elzarrad MK, Seaman S, Zudaire E, Stevens J, Yang MY, Li X, Chaudhary A, Xu L, Hilton MB, Logsdon D, Hsiao E, Stein EV, Cuttitta F, Haines DC, Nagashima K, Tessarollo L, St. Croix B. GPR124, an orphan G protein-coupled receptor, is required for CNS-specific vascularization and establishment of the blood-brain barrier. Proc Natl Acad Sci U S A 2011; 108:5759-64. [PMID: 21421844 PMCID: PMC3078373 DOI: 10.1073/pnas.1017192108] [Citation(s) in RCA: 144] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Every organ in the body requires blood vessels for efficient delivery of oxygen and nutrients, but independent vascular beds are highly specialized to meet the individual needs of specific organs. The vasculature of the brain is tightly sealed, with blood-brain barrier (BBB) properties developing coincident with neural vascularization. G protein-coupled receptor 124 (GPR124) (tumor endothelial marker 5, TEM5), an orphan member of the adhesion family of G protein-coupled receptors, was previously identified on the basis of its overexpression in tumor vasculature. Here, we show that global deletion or endothelial-specific deletion of GPR124 in mice results in embryonic lethality associated with abnormal angiogenesis of the forebrain and spinal cord. Expression of GPR124 was found to be required for invasion and migration of blood vessels into neuroepithelium, establishment of BBB properties, and expansion of the cerebral cortex. Thus, GPR124 is an important regulator of neurovasculature development and a potential drug target for cerebrovascular diseases.
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Affiliation(s)
- Mike Cullen
- Tumor Angiogenesis Section, Mouse Cancer Genetics Program, National Cancer Institute, National Institutes of Health, Frederick, MD 21702
| | - Mohammed K. Elzarrad
- Tumor Angiogenesis Section, Mouse Cancer Genetics Program, National Cancer Institute, National Institutes of Health, Frederick, MD 21702
| | - Steven Seaman
- Tumor Angiogenesis Section, Mouse Cancer Genetics Program, National Cancer Institute, National Institutes of Health, Frederick, MD 21702
| | - Enrique Zudaire
- Angiogenesis Core Facility, National Cancer Institute, National Institutes of Health, Gaithersburg, MD, 20877
| | - Janine Stevens
- Tumor Angiogenesis Section, Mouse Cancer Genetics Program, National Cancer Institute, National Institutes of Health, Frederick, MD 21702
| | - Mi Young Yang
- Tumor Angiogenesis Section, Mouse Cancer Genetics Program, National Cancer Institute, National Institutes of Health, Frederick, MD 21702
| | - Xiujie Li
- Tumor Angiogenesis Section, Mouse Cancer Genetics Program, National Cancer Institute, National Institutes of Health, Frederick, MD 21702
| | - Amit Chaudhary
- Tumor Angiogenesis Section, Mouse Cancer Genetics Program, National Cancer Institute, National Institutes of Health, Frederick, MD 21702
| | - Lihong Xu
- Tumor Angiogenesis Section, Mouse Cancer Genetics Program, National Cancer Institute, National Institutes of Health, Frederick, MD 21702
| | - Mary Beth Hilton
- Tumor Angiogenesis Section, Mouse Cancer Genetics Program, National Cancer Institute, National Institutes of Health, Frederick, MD 21702
- Basic Research Program
| | | | - Emily Hsiao
- Tumor Angiogenesis Section, Mouse Cancer Genetics Program, National Cancer Institute, National Institutes of Health, Frederick, MD 21702
| | - Erica V. Stein
- Tumor Angiogenesis Section, Mouse Cancer Genetics Program, National Cancer Institute, National Institutes of Health, Frederick, MD 21702
| | - Frank Cuttitta
- Angiogenesis Core Facility, National Cancer Institute, National Institutes of Health, Gaithersburg, MD, 20877
| | - Diana C. Haines
- Veterinary Pathology Section, Pathology/Histotechnology Laboratory, and
| | - Kunio Nagashima
- Image Analysis Laboratory, Advanced Technology Program, Science Applications International Corporation (SAIC), National Cancer Institute, Frederick, MD 21702; and
| | - Lino Tessarollo
- Neural Development Section, Mouse Cancer Genetics Program, National Cancer Institute, National Institutes of Health, Frederick, MD 21702
| | - Brad St. Croix
- Tumor Angiogenesis Section, Mouse Cancer Genetics Program, National Cancer Institute, National Institutes of Health, Frederick, MD 21702
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Cheng Z, Garvin D, Paguio A, Stecha P, Wood K, Fan F. Luciferase Reporter Assay System for Deciphering GPCR Pathways. CURRENT CHEMICAL GENOMICS 2010; 4:84-91. [PMID: 21331312 PMCID: PMC3040460 DOI: 10.2174/1875397301004010084] [Citation(s) in RCA: 140] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/21/2010] [Revised: 10/25/2010] [Accepted: 10/25/2010] [Indexed: 11/22/2022]
Abstract
The G protein coupled receptors (GPCR) represent the target class for nearly half of the current therapeutic drugs and remain to be the focus of drug discovery efforts. The complexity of receptor signaling continues to evolve. It is now known that many GPCRs are coupled to multiple G-proteins, which lead to regulation of respective signaling pathways downstream. Deciphering this receptor coupling will aid our understanding of the GPCR function and ultimately developing drug candidates. Here, we report the development of four homogenous bioluminescent reporter assays using improved destabilized luciferases and various response elements: CRE, NFAT-RE, SRE, and SRF-RE. These assays allowed measurement of major GPCR pathways including cAMP production, intracellular Ca2+ mobilizations, ERK/MAPK activ-ity, and small G protein RhoA activity, respectively using the same reporter assay format. We showed that we can decipher G protein activation profiles for exogenous m3 muscarinic receptor and endogenous β2-adrenergic receptors in HEK293 cells by using these four reporter assays. Furthermore, we demonstrated that these assays can be readily used for potency rankings of agonists and antagonists, and for high throughput screening.
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Affiliation(s)
- Zhijie Cheng
- Department of Research, Promega Corporation, Madison, WI53711, USA
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Xia R, Hu Z, Sun Y, Chen S, Gu M, Zhou Y, Han Z, Zhong R, Deng A, Wen H. Overexpression of beta-arrestin 2 in peripheral blood mononuclear cells of patients with cryptococcal meningitis. J Interferon Cytokine Res 2010; 30:155-62. [PMID: 20035620 DOI: 10.1089/jir.2009.0017] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Cryptococcal meningitis is often associated with elevated IL-10 levels, which suggest a dysregulation in the antifungal immune response. beta-Arrestin 2 plays a major role in desensitization of G-protein-coupled receptors involved in the immune responses, provides a scaffolding platform for modification of many signal transduction proteins, and binds Src and MAP kinases family members. This study compared the levels of beta-arrestin 2 mRNA and protein in peripheral blood mononuclear cells (PBMC) of patients with cryptococcal meningitis detected. The interferon-gamma (IFN-gamma) serum concentration was determined with enzyme-linked immunosorbent assay (ELISA) to reveal its relationship with beta-arrestin 2. The effect of modulation of beta-arrestin 2 on cytotoxic activity against Cryptococcus was explored via transfection and interference of beta-arrestin 2. PBMCs of patients with cryptococcal meningitis exhibited significantly elevated levels of beta-arrestin 2 and a positive correlation between beta-arrestin 2 and IL-10 levels existed in patients' serum, but a negative correlation was found between beta-arrestin 2 and IFN-gamma expression. In conclusion, elevated expression of beta-arrestin 2 in PBMCs of patients with cryptococcal meningitis correlated with a reduced cytotoxic activity against Cryptococcus. This study suggests that reduced beta-arrestin 2 mRNA levels or inhibition of beta-arrestin 2 activity may augment INF-gamma production, and ultimately, the anti-Cryptococcus immune response of infected patients.
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Affiliation(s)
- Rong Xia
- Department of Transfusion, Huashan Hospital, Fudan University, Shanghai, People's Republic of China
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Goncalves JA, Ahuja S, Erfani S, Eilers M, Smith SO. Structure and function of G protein-coupled receptors using NMR spectroscopy. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2010; 57:159-80. [PMID: 20633362 PMCID: PMC2907352 DOI: 10.1016/j.pnmrs.2010.04.004] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2010] [Accepted: 04/08/2010] [Indexed: 05/15/2023]
Affiliation(s)
- Joseph A Goncalves
- Department of Biochemistry and Cell Biology, Center for Structural Biology, Stony Brook University, Stony Brook, NY 11794-5215, USA
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Abstract
Seven-transmembrane receptors (7TMRs; also known as G protein-coupled receptors) are the largest class of receptors in the human genome and are common targets for therapeutics. Originally identified as mediators of 7TMR desensitization, beta-arrestins (arrestin 2 and arrestin 3) are now recognized as true adaptor proteins that transduce signals to multiple effector pathways. Signalling that is mediated by beta-arrestins has distinct biochemical and functional consequences from those mediated by G proteins, and several biased ligands and receptors have been identified that preferentially signal through either G protein- or beta-arrestin-mediated pathways. These ligands are not only useful tools for investigating the biochemistry of 7TMR signalling, they also have the potential to be developed into new classes of therapeutics.
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Biotech Paper watch: Signaling. Biotechnol J 2010. [DOI: 10.1002/biot.201000051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Córdoba-Chacón J, Gahete MD, Duran-Prado M, Pozo-Salas AI, Malagón MM, Gracia-Navarro F, Kineman RD, Luque RM, Castaño JP. Identification and characterization of new functional truncated variants of somatostatin receptor subtype 5 in rodents. Cell Mol Life Sci 2010; 67:1147-63. [PMID: 20063038 PMCID: PMC11115927 DOI: 10.1007/s00018-009-0240-y] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2009] [Revised: 12/08/2009] [Accepted: 12/18/2009] [Indexed: 12/11/2022]
Abstract
Somatostatin and cortistatin exert multiple biological actions through five receptors (sst1-5); however, not all their effects can be explained by activation of sst1-5. Indeed, we recently identified novel truncated but functional human sst5-variants, present in normal and tumoral tissues. In this study, we identified and characterized three novel truncated sst5 variants in mice and one in rats displaying different numbers of transmembrane-domains [TMD; sst5TMD4, sst5TMD2, sst5TMD1 (mouse-variants) and sst5TMD1 (rat-variant)]. These sst5 variants: (1) are functional to mediate ligand-selective-induced variations in [Ca(2+)]i and cAMP despite being truncated; (2) display preferential intracellular distribution; (3) mostly share full-length sst5 tissue distribution, but exhibit unique differences; (4) are differentially regulated by changes in hormonal/metabolic environment in a tissue- (e.g., central vs. systemic) and ligand-dependent manner. Altogether, our results demonstrate the existence of new truncated sst5-variants with unique ligand-selective signaling properties, which could contribute to further understanding the complex, distinct pathophysiological roles of somatostatin and cortistatin.
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Affiliation(s)
- Jose Córdoba-Chacón
- Department of Cell Biology, Physiology and Immunology, University of Córdoba, Edificio Severo Ochoa. Planta 3. Campus de Rabanales, 14014 Córdoba, Spain
- Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), Córdoba, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBERobn 06/03), Córdoba, Spain
| | - Manuel D. Gahete
- Department of Cell Biology, Physiology and Immunology, University of Córdoba, Edificio Severo Ochoa. Planta 3. Campus de Rabanales, 14014 Córdoba, Spain
- Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), Córdoba, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBERobn 06/03), Córdoba, Spain
| | - Mario Duran-Prado
- Department of Cell Biology, Physiology and Immunology, University of Córdoba, Edificio Severo Ochoa. Planta 3. Campus de Rabanales, 14014 Córdoba, Spain
- Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), Córdoba, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBERobn 06/03), Córdoba, Spain
| | - Ana I. Pozo-Salas
- Department of Cell Biology, Physiology and Immunology, University of Córdoba, Edificio Severo Ochoa. Planta 3. Campus de Rabanales, 14014 Córdoba, Spain
- Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), Córdoba, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBERobn 06/03), Córdoba, Spain
| | - María M. Malagón
- Department of Cell Biology, Physiology and Immunology, University of Córdoba, Edificio Severo Ochoa. Planta 3. Campus de Rabanales, 14014 Córdoba, Spain
- Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), Córdoba, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBERobn 06/03), Córdoba, Spain
| | - F. Gracia-Navarro
- Department of Cell Biology, Physiology and Immunology, University of Córdoba, Edificio Severo Ochoa. Planta 3. Campus de Rabanales, 14014 Córdoba, Spain
- Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), Córdoba, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBERobn 06/03), Córdoba, Spain
| | - Rhonda D. Kineman
- Research and Development Division, Jesse Brown Veterans Affairs Medical Center, Chicago, IL USA
- Section of Endocrinology, Diabetes and Metabolism, Department of Medicine, University of Illinois at Chicago, Chicago, IL USA
| | - Raul M. Luque
- Department of Cell Biology, Physiology and Immunology, University of Córdoba, Edificio Severo Ochoa. Planta 3. Campus de Rabanales, 14014 Córdoba, Spain
- Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), Córdoba, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBERobn 06/03), Córdoba, Spain
| | - Justo P. Castaño
- Department of Cell Biology, Physiology and Immunology, University of Córdoba, Edificio Severo Ochoa. Planta 3. Campus de Rabanales, 14014 Córdoba, Spain
- Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC), Córdoba, Spain
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBERobn 06/03), Córdoba, Spain
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Birgbauer E, Chun J. Lysophospholipid receptors LPA 1-3 are not required for the inhibitory effects of LPA on mouse retinal growth cones. Eye Brain 2010; 2:1-13. [PMID: 26966392 DOI: 10.2147/eb.s7666] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
One of the major requirements in the development of the visual system is axonal guidance of retinal ganglion cells toward correct targets in the brain. A novel class of extracellular lipid signaling molecules, lysophospholipids, may serve as potential axon guidance cues. They signal through cognate G protein-coupled receptors, at least some of which are expressed in the visual system. Here we show that in the mouse visual system, a lysophospholipid known as lysophosphatidic acid (LPA) is inhibitory to retinal neurites in vitro when delivered extracellularly, causing growth cone collapse and neurite retraction. This inhibitory effect of LPA is both active in the nanomolar range and specific compared to the related lysophospholipid, sphingosine 1-phosphate (S1P). Knockout mice lacking three of the five known LPA receptors, LPA1-3, continue to display retinal growth cone collapse and neurite retraction in response to LPA, demonstrating that these three receptors are not required for these inhibitory effects and indicating the existence of one or more functional LPA receptors expressed on mouse retinal neurites that can mediate neurite retraction.
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Affiliation(s)
- Eric Birgbauer
- Department of Molecular Biology, Helen L Dorris Institute for Neurological and Psychiatric Disorders, The Scripps Research Institute, La Jolla, CA, USA
| | - Jerold Chun
- Department of Molecular Biology, Helen L Dorris Institute for Neurological and Psychiatric Disorders, The Scripps Research Institute, La Jolla, CA, USA
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Kahlig KM, Saridey SK, Kaja A, Daniels MA, George AL, Wilson MH. Multiplexed transposon-mediated stable gene transfer in human cells. Proc Natl Acad Sci U S A 2010; 107:1343-8. [PMID: 20080581 PMCID: PMC2824351 DOI: 10.1073/pnas.0910383107] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Generation of cultured human cells stably expressing one or more recombinant gene sequences is a widely used approach in biomedical research, biotechnology, and drug development. Conventional methods are not efficient and have severe limitations especially when engineering cells to coexpress multiple transgenes or multiprotein complexes. In this report, we harnessed the highly efficient, nonviral, and plasmid-based piggyBac transposon system to enable concurrent genomic integration of multiple independent transposons harboring distinct protein-coding DNA sequences. Flow cytometry of cell clones derived from a single multiplexed transfection demonstrated approximately 60% (three transposons) or approximately 30% (four transposons) stable coexpression of all delivered transgenes with selection for a single marker transposon. We validated multiplexed piggyBac transposon delivery by coexpressing large transgenes encoding a multisubunit neuronal voltage-gated sodium channel (SCN1A) containing a pore-forming subunit and two accessory subunits while using two additional genes for selection. Previously unobtainable robust sodium current was demonstrated through 38 passages, suitable for use on an automated high-throughput electrophysiology platform. Cotransfection of three large (up to 10.8 kb) piggyBac transposons generated a heterozygous SCN1A stable cell line expressing two separate alleles of the pore-forming subunit and two accessory subunits (total of four sodium channel subunits) with robust functional expression. We conclude that the piggyBac transposon system can be used to perform multiplexed stable gene transfer in cultured human cells, and this technology may be valuable for applications requiring concurrent expression of multiprotein complexes.
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Affiliation(s)
| | | | | | | | - Alfred L. George
- Department of Medicine and
- Department of Pharmacology, Vanderbilt University, Nashville, TN 37235
| | - Matthew H. Wilson
- Michael E. DeBakey VA Medical Center
- Department of Medicine, and
- Center for Cell and Gene Therapy, Baylor College of Medicine, Houston, TX 77030
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Durán-Prado M, Gahete MD, Martínez-Fuentes AJ, Luque RM, Quintero A, Webb SM, Benito-López P, Leal A, Schulz S, Gracia-Navarro F, Malagón MM, Castaño JP. Identification and characterization of two novel truncated but functional isoforms of the somatostatin receptor subtype 5 differentially present in pituitary tumors. J Clin Endocrinol Metab 2009; 94:2634-43. [PMID: 19401364 DOI: 10.1210/jc.2008-2564] [Citation(s) in RCA: 103] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
CONTEXT Somatostatin and its related peptide cortistatin exert multiple actions on normal and tumoral tissue targets through a family of receptors termed somatostatin receptor (sst)1-5. Despite the considerable advances in the knowledge on these receptors and their (patho)physiological roles, there is still evidence that additional receptors for these peptides should exist to fully explain their actions. OBJECTIVE The growing number of spliced variants found in similar receptor families, often present in tumors, and results from our group obtained on sst5 from other species (pig) led us to explore the existence of new human sst5 isoforms. DESIGN AND RESULTS A rapid amplification of cDNA ends PCR approach on samples from a human pituitary tumor and a cell line enabled identification of two novel alternatively spliced sst5 receptor variants. The sequences obtained encode putative proteins that correspond to truncated isoforms of five and four transmembrane domains (TMDs), accordingly named sst5TMD5 and sst5TMD4, respectively. Both novel receptors show a differential expression pattern in normal tissues and are also present in pituitary tumors of diverse etiology including nonfunctioning adenomas, corticotropinomas, somatotropinomas, and a prolactinoma. In contrast to the predominant plasma membrane localization of full-length sst5, both sst5TMD5 and sst5TMD4 show a preferentially intracellular localization. Despite their truncated nature, both receptors are functional, as shown by their ability to mediate selective, ligand-induced rises in free cytosolic calcium concentration. Specifically, whereas sst5TMD5 is selectivity activated by somatostatin compared with cortistatin, cells transfected with sst5TMD4 almost exclusively respond to cortistatin and not to somatostatin. CONCLUSIONS Our results demonstrate the existence of two previously unidentified sst5 spliced variants with distinct distribution in normal tissues and pituitary tumors, unique ligand-selective signaling properties, and subcellular distribution, which could contribute to somatostatin and cortistatin signaling in normal and tumoral cells.
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Affiliation(s)
- Mario Durán-Prado
- Department of Cell Biology, Physiology, and Immunology, University of Córdoba, and Centro de Investigación Biomédica en Red Fisiopatología de la Obesidad y Nutrición, E-14014 Córdoba Spain
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Ueda T, Ugawa S, Ishida Y, Hondoh A, Shimada S. Development of Generic Calcium Imaging Assay for Monitoring Gi-Coupled Receptors and G-Protein Interaction. ACTA ACUST UNITED AC 2009; 14:781-8. [DOI: 10.1177/1087057109335258] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
G-protein-coupled receptors (GPCRs) are important therapeutic targets for many areas of drug research and development. Although chimeric Gα16 proteins are valuable tools for detecting the activation of Gαi/o-coupled receptors, the details of the activation process remain unclear. The authors introduce a series of chimeras that combine both Gα16 and Gα i/o (Gα16/o, Gα16/i2, and Gα 16/i3) into a well-established transient expression system to examine the ability of these chimeras to interact with D2 long-form (D 2L) dopamine and 5-HT1A serotonin receptors. The pEC 50 data obtained for known agonists were similar to results from previous studies that used other cell-based assays, thus indicating sufficient sensitivity for the assay. Moreover, quinpirole exhibited similar intrinsic activity to dopamine at the D2L receptor, whereas S-(—)-3-PPP displayed partial activity of dopamine and quinpirole in the presence of the Gα16/o chimera. The potency of dopamine for D2L receptors was similar among Gα16/o, Gα16/i2, and Gα 16/i3. In contrast, the 5-HT1A receptor exhibited a significantly preferential coupling for Gα16/i3 compared with Gα 16/i2 when serotonin was used as a ligand. This finding was in close agreement with the results of previous reports. The present system could therefore be used as a rapid functional assay for high-throughput screening and deorphanization. ( Journal of Biomolecular Screening 2009:781-788)
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Affiliation(s)
- Takashi Ueda
- Department of Neurobiology and Anatomy, Graduate School of Medical Science, Nagoya City University, Nagoya, Japan,
| | - Shinya Ugawa
- Department of Neurobiology and Anatomy, Graduate School of Medical Science, Nagoya City University, Nagoya, Japan
| | - Yusuke Ishida
- Department of Neurobiology and Anatomy, Graduate School of Medical Science, Nagoya City University, Nagoya, Japan
| | - Aki Hondoh
- Department of Neurobiology and Anatomy, Graduate School of Medical Science, Nagoya City University, Nagoya, Japan
| | - Shoichi Shimada
- Department of Neurobiology and Anatomy, Graduate School of Medical Science, Nagoya City University, Nagoya, Japan
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van der Lee MMC, Blomenröhr M, van der Doelen AA, Wat JWY, Smits N, Hanson BJ, van Koppen CJ, Zaman GJR. Pharmacological characterization of receptor redistribution and beta-arrestin recruitment assays for the cannabinoid receptor 1. ACTA ACUST UNITED AC 2009; 14:811-23. [PMID: 19520790 DOI: 10.1177/1087057109337937] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Receptor redistribution and beta-arrestin recruitment assays provide a G-protein-subtype-independent method to measure ligand-stimulated activation of G-protein-coupled receptors. In particular beta-arrestin assays are becoming an increasingly popular tool for drug discovery. The authors have compared a high-content-imaging-based Redistribution assay and 2 nonimaging-based beta-arrestin recruitment assays, Tango and PathHunter, for the cannabinoid receptor 1. Inasmuch as all 3 assays use receptors that are modified at the C-terminus, the authors verified their pharmacology via detection of Galpha(i) coupling of the receptor in cAMP assays using reference ligands. The potencies and efficacies of the cannabinoid receptor agonists CP55,940 and WIN55,212-2 correlated well between the 3 assays, and are comparable with the measured ligand binding affinities. The inverse agonist SR141716 decreased basal signal in all 3 assays, but only in the Tango bla assay a reliable EC50 could be determined for this compound, suggesting that Tango is the most suitable assay for the identification of new inverse agonists. Both the Redistribution and the PathHunter assay could discriminate partial agonists from full agonists, whereas in the Tango assay partial agonists behaved as full agonists. Only the PathHunter cells allowed detection of cannabinoid receptor activation via beta-arrestin recruitment and Galpha(i)-protein-mediated inhibition of cAMP, thus enabling the identification of biased ligands that differ in these cellular effects. The characteristics and limitations of the different assays are discussed.
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Yin H, Chu A, Li W, Wang B, Shelton F, Otero F, Nguyen DG, Caldwell JS, Chen YA. Lipid G protein-coupled receptor ligand identification using beta-arrestin PathHunter assay. J Biol Chem 2009; 284:12328-38. [PMID: 19286662 DOI: 10.1074/jbc.m806516200] [Citation(s) in RCA: 245] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
A growing number of orphan G-protein-coupled receptors (GPCRs) have been reported to be activated by lipid ligands, such as lysophosphatidic acid, sphingosine 1-phosphate (S1P), and cannabinoids, for which there are already well established receptors. These new ligand claims are controversial due to either lack of independent confirmations or conflicting reports. We used the beta-arrestin PathHunter assay system, a newly developed, generic GPCR assay format that measures beta-arrestin binding to GPCRs, to evaluate lipid receptor and ligand pairing. This assay eliminates interference from endogenous receptors on the parental cells because it measures a signal that is specifically generated by the tagged receptor and is immediately downstream of receptor activation. We screened a large number of newly "deorphaned" receptors (GPR23, GPR92, GPR55, G2A, GPR18, GPR3, GPR6, GPR12, and GPR63) and control receptors against a collection of approximately 400 lipid molecules to try to identify the receptor ligand in an unbiased fashion. GPR92 was confirmed to be a lysophosphatidic acid receptor with weaker responses to farnesyl pyrophosphate and geranylgeranyl diphosphate. The putative cannabinoid receptor GPR55 responded strongly to AM251, rimonabant, and lysophosphatidylinositol but only very weakly to endocannabinoids. G2A receptor was confirmed to be an oxidized free fatty acid receptor. In addition, we discovered that 3,3'-diindolylmethane, a dietary molecule from cruciferous vegetables, which has known anti-cancer properties, to be a CB(2) receptor partial agonist, with binding affinity around 1 microm. The anti-inflammatory effect of 3,3'-diindolylmethane in RAW264.7 cells was shown to be partially mediated by CB(2).
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Affiliation(s)
- Hong Yin
- GPCR Platform, Genomics Institute of the Novartis Research Foundation, San Diego, California 92121, USA
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Hay DL. Measurement of Phosphorylated Extracellular Signal-Regulated Kinase 1 and 2 in an Undergraduate Teaching Laboratory with ALPHAscreen Technology. Sci Signal 2009; 2:tr1. [DOI: 10.1126/scisignal.262tr1] [Citation(s) in RCA: 78] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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Abstract
G protein-coupled receptors (GPCRs) represent a large family of seven transmembrane receptors, which communicate extracellular signals into the cellular lumen. The human genome contains 720-800 GPCRs, and their diverse signal characteristics are determined by their specific tissue and subcellular expression profiles, as well as their coupling profile to the various G protein families (G(s), G(i), G(q), G(12)). The G protein coupling pattern links GPCR activation to the specific downstream effector pathways. G(12/13) signalling of GPCRs has been studied only recently in more detail, and involves activation of RhoGTPase nucleotide exchange factors (RhoGEFs). Four mammalian RhoGEFs regulated by G(12/13) proteins are known: p115-RhoGEF, PSD-95/Disc-large/ZO-1 homology-RhoGEF, leukemia-associated RhoGEF and lymphoid blast crisis-RhoGEF. These link GPCRs to activation of the small monomeric GTPase RhoA, and other downstream effectors. Misregulated G(12/13) signalling is involved in multiple pathophysiological conditions such as cancer, cardiovascular diseases, arterial and pulmonary hypertension, and bronchial asthma. Specific targeting of G(12/13) signalling-related diseases of GPCRs hence provides novel therapeutic approaches. Assays to quantitatively measure GPCR-mediated activation of G(12/13) are only emerging, and are required to understand the G(12/13)-linked pharmacology. The review gives an overview of G(12/13) signalling of GPCRs with a focus on RhoGEF proteins as the immediate mediators of G(12/13) activation.
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Affiliation(s)
- Sandra Siehler
- Novartis Institutes for BioMedical Research Basel, Center for Proteomic Chemistry, Novartis Pharma AG, Basel, Switzerland.
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Heilker R, Wolff M, Tautermann CS, Bieler M. G-protein-coupled receptor-focused drug discovery using a target class platform approach. Drug Discov Today 2009; 14:231-40. [PMID: 19121411 DOI: 10.1016/j.drudis.2008.11.011] [Citation(s) in RCA: 115] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2008] [Revised: 11/05/2008] [Accepted: 11/26/2008] [Indexed: 11/27/2022]
Abstract
In recent years, several large pharmaceutical companies have taken a novel approach to drug discovery biology and chemistry in that they channel their efforts with respect to particular target classes, such as G-protein-coupled receptors (GPCRs), toward dedicated, specialized teams. Benefits of such an organizational structure are the prospects of establishing several target-family-specific experimental techniques and skill sets, thereby enabling a comprehensive functional profiling of drug candidates in different pharmacological respects. In this context, the recently increased number of reports on GPCR ligand-biased signaling has further spurred the efforts in the pharmaceutical industry toward broader biological characterization of the test compounds, for example employing high-content screening to analyze different GPCR ligand-induced signaling pathways. The knowledge of the disease-relevant functional properties of the small molecule GPCR ligands enables target-specific chemical optimization and GPCR-subclass-directed library design. In the case of GPCRs, where little--although at present slowly expanding--structural information on the targets is available, the modeling of GPCR structures crucially depends on biological validation (typically supported by site-directed mutagenesis of the GPCR ligand binding site). In this review, we aim to recapitulate efforts in the pharmaceutical industry to address GPCR-directed drug discovery in a target-class-directed platform approach: establishing GPCR-specific biological assay panels and creating computational chemistry methods for finding and optimizing small molecules modulating the activity of GPCRs.
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Affiliation(s)
- Ralf Heilker
- Department of Lead Discovery, Boehringer Ingelheim Pharma GmbH & Co KG, Biberach, Germany.
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Panetta R, Greenwood MT. Physiological relevance of GPCR oligomerization and its impact on drug discovery. Drug Discov Today 2008; 13:1059-66. [DOI: 10.1016/j.drudis.2008.09.002] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2008] [Revised: 08/21/2008] [Accepted: 09/01/2008] [Indexed: 12/20/2022]
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Paper & market watch. Biotechnol J 2008. [DOI: 10.1002/biot.200890061] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Dekker L. Editorial: Novel approaches to drug discovery in signal transduction. Biotechnol J 2008; 3:428-9. [DOI: 10.1002/biot.200890035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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