1
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Cullum SA, Platt S, Dale N, Isaac OC, Wragg ES, Soave M, Veprintsev DB, Woolard J, Kilpatrick LE, Hill SJ. Mechano-sensitivity of β2-adrenoceptors enhances constitutive activation of cAMP generation that is inhibited by inverse agonists. Commun Biol 2024; 7:417. [PMID: 38580813 PMCID: PMC10997663 DOI: 10.1038/s42003-024-06128-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2023] [Accepted: 03/29/2024] [Indexed: 04/07/2024] Open
Abstract
The concept of agonist-independent signalling that can be attenuated by inverse agonists is a fundamental element of the cubic ternary complex model of G protein-coupled receptor (GPCR) activation. This model shows how a GPCR can exist in two conformational states in the absence of ligands; an inactive R state and an active R* state that differ in their affinities for agonists, inverse agonists, and G-protein alpha subunits. The proportion of R* receptors that exist in the absence of agonists determines the level of constitutive receptor activity. In this study we demonstrate that mechanical stimulation can induce β2-adrenoceptor agonist-independent Gs-mediated cAMP signalling that is sensitive to inhibition by inverse agonists such as ICI-118551 and propranolol. The size of the mechano-sensitive response is dependent on the cell surface receptor expression level in HEK293G cells, is still observed in a ligand-binding deficient D113A mutant β2-adrenoceptor and can be attenuated by site-directed mutagenesis of the extracellular N-glycosylation sites on the N-terminus and second extracellular loop of the β2-adrenoceptor. Similar mechano-sensitive agonist-independent responses are observed in HEK293G cells overexpressing the A2A-adenosine receptor. These data provide new insights into how agonist-independent constitutive receptor activity can be enhanced by mechanical stimulation and regulated by inverse agonists.
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Affiliation(s)
- Sean A Cullum
- Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Nottingham, NG7 2UH, UK
- Centre of Membrane Proteins and Receptors, University of Nottingham, Nottingham, NG7 2UH, UK
| | - Simon Platt
- Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Nottingham, NG7 2UH, UK
- Centre of Membrane Proteins and Receptors, University of Nottingham, Nottingham, NG7 2UH, UK
| | - Natasha Dale
- Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Nottingham, NG7 2UH, UK
- Centre of Membrane Proteins and Receptors, University of Nottingham, Nottingham, NG7 2UH, UK
| | - Oliver C Isaac
- Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Nottingham, NG7 2UH, UK
- Centre of Membrane Proteins and Receptors, University of Nottingham, Nottingham, NG7 2UH, UK
| | - Edward S Wragg
- Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Nottingham, NG7 2UH, UK
- Centre of Membrane Proteins and Receptors, University of Nottingham, Nottingham, NG7 2UH, UK
| | - Mark Soave
- Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Nottingham, NG7 2UH, UK
- Centre of Membrane Proteins and Receptors, University of Nottingham, Nottingham, NG7 2UH, UK
| | - Dmitry B Veprintsev
- Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Nottingham, NG7 2UH, UK
- Centre of Membrane Proteins and Receptors, University of Nottingham, Nottingham, NG7 2UH, UK
| | - Jeanette Woolard
- Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Nottingham, NG7 2UH, UK
- Centre of Membrane Proteins and Receptors, University of Nottingham, Nottingham, NG7 2UH, UK
| | - Laura E Kilpatrick
- Centre of Membrane Proteins and Receptors, University of Nottingham, Nottingham, NG7 2UH, UK
- Division of Bimolecular Science and Medicinal Chemistry, School of Pharmacy, Biodiscovery Institute, University of Nottingham, Nottingham, NG7 2RD, UK
| | - Stephen J Hill
- Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Nottingham, NG7 2UH, UK.
- Centre of Membrane Proteins and Receptors, University of Nottingham, Nottingham, NG7 2UH, UK.
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2
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Bernard C, Carotenuto AR, Pugno NM, Fraldi M, Deseri L. Modelling lipid rafts formation through chemo-mechanical interplay triggered by receptor-ligand binding. Biomech Model Mechanobiol 2024; 23:485-505. [PMID: 38060155 DOI: 10.1007/s10237-023-01787-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Accepted: 10/21/2023] [Indexed: 12/08/2023]
Abstract
Cell membranes, mediator of many biological mechanisms from adhesion and metabolism up to mutation and infection, are highly dynamic and heterogeneous environments exhibiting a strong coupling between biochemical events and structural re-organisation. This involves conformational changes induced, at lower scales, by lipid order transitions and by the micro-mechanical interplay of lipids with transmembrane proteins and molecular diffusion. Particular attention is focused on lipid rafts, ordered lipid microdomains rich of signalling proteins, that co-localise to enhance substance trafficking and activate different intracellular biochemical pathways. In this framework, the theoretical modelling of the dynamic clustering of lipid rafts implies a full multiphysics coupling between the kinetics of phase changes and the mechanical work performed by transmembrane proteins on lipids, involving the bilayer elasticity. This mechanism produces complex interspecific dynamics in which membrane stresses and chemical potentials do compete by determining different morphological arrangements, alteration in diffusive walkways and coalescence phenomena, with a consequent influence on both signalling potential and intracellular processes. Therefore, after identifying the leading chemo-mechanical interactions, the present work investigates from a modelling perspective the spatio-temporal evolution of raft domains to theoretically explain co-localisation and synergy between proteins' activation and raft formation, by coupling diffusive and mechanical phenomena to observe different morphological patterns and clustering of ordered lipids. This could help to gain new insights into the remodelling of cell membranes and could potentially suggest mechanically based strategies to control their selectivity, by orienting intracellular functions and mechanotransduction.
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Affiliation(s)
- Chiara Bernard
- Department of Civil, Environmental and Mechanical Engineering, University of Trento, Trento, Italy
| | - Angelo Rosario Carotenuto
- Department of Structures for Engineering and Architecture, University of Naples "Federico II", Naples, Italy
- Laboratory of Integrated Mechanics and Imaging for Testing and Simulation (LIMITS), University of Naples "Federico II", Naples, Italy
| | - Nicola Maria Pugno
- Department of Civil, Environmental and Mechanical Engineering, University of Trento, Trento, Italy
- Laboratory for Bioinspired, Bionic, Nano, Meta Materials and Mechanics, University of Trento, Trento, Italy
- School of Engineering and Materials Science, Queen Mary University of London, London, UK
| | - Massimiliano Fraldi
- Department of Structures for Engineering and Architecture, University of Naples "Federico II", Naples, Italy
- Laboratory of Integrated Mechanics and Imaging for Testing and Simulation (LIMITS), University of Naples "Federico II", Naples, Italy
- Département de Physique, LPENS, École Normale Supérieure-PSL, Paris, France
| | - Luca Deseri
- Department of Civil, Environmental and Mechanical Engineering, University of Trento, Trento, Italy.
- Department of Mechanical Engineering and Material Sciences, MEMS-SSoE, University of Pittsburgh, Pittsburgh, USA.
- Department of Civil and Environmental Engineering, Carnegie Mellon University, Pittsburgh, USA.
- Department of Mechanical Engineering, Carnegie Mellon University, Pittsburgh, USA.
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3
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Che T, Roth BL. Molecular basis of opioid receptor signaling. Cell 2023; 186:5203-5219. [PMID: 37995655 PMCID: PMC10710086 DOI: 10.1016/j.cell.2023.10.029] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Revised: 10/13/2023] [Accepted: 10/27/2023] [Indexed: 11/25/2023]
Abstract
Opioids are used for pain management despite the side effects that contribute to the opioid crisis. The pursuit of non-addictive opioid analgesics remains unattained due to the unresolved intricacies of opioid actions, receptor signaling cascades, and neuronal plasticity. Advancements in structural, molecular, and computational tools illuminate the dynamic interplay between opioids and opioid receptors, as well as the molecular determinants of signaling pathways, which are potentially interlinked with pharmacological responses. Here, we review the molecular basis of opioid receptor signaling with a focus on the structures of opioid receptors bound to endogenous peptides or pharmacological agents. These insights unveil specific interactions that dictate ligand selectivity and likely their distinctive pharmacological profiles. Biochemical analysis further unveils molecular features governing opioid receptor signaling. Simultaneously, the synergy between computational biology and medicinal chemistry continues to expedite the discovery of novel chemotypes with the promise of yielding more efficacious and safer opioid compounds.
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Affiliation(s)
- Tao Che
- Department of Anesthesiology, Washington University School of Medicine, Saint Louis, MO 63110, USA; Center for Clinical Pharmacology, University of Health Sciences & Pharmacy and Washington University School of Medicine, Saint Louis, MO 63110, USA.
| | - Bryan L Roth
- Department of Pharmacology, University of North Carolina Chapel Hill School of Medicine, Chapel Hill 27599, NC, USA.
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4
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Tyagi R, Saraf TS, Canal CE. The Psychedelic N, N-Dipropyltryptamine Prevents Seizures in a Mouse Model of Fragile X Syndrome via a Mechanism that Appears Independent of Serotonin and Sigma1 Receptors. ACS Pharmacol Transl Sci 2023; 6:1480-1491. [PMID: 37854624 PMCID: PMC10580393 DOI: 10.1021/acsptsci.3c00137] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Indexed: 10/20/2023]
Abstract
The serotonergic psychedelic psilocybin shows efficacy in treating neuropsychiatric disorders, though the mechanism(s) underlying its therapeutic effects remain unclear. We show that a similar psychedelic tryptamine, N,N-dipropyltryptamine (DPT), completely prevents audiogenic seizures (AGS) in an Fmr1 knockout mouse model of fragile X syndrome at a 10 mg/kg dose but not at lower doses (3 or 5.6 mg/kg). Despite showing in vitro that DPT is a serotonin 5-HT2A, 5-HT1B, and 5-HT1A receptor agonist (with that rank order of functional potency, determined with TRUPATH Gα/βγ biosensors), pretreatment with selective inhibitors of 5-HT2A/2C, 5-HT1B, or 5-HT1A receptors did not block DPT's antiepileptic effects; a pan-serotonin receptor antagonist was also ineffective. Because 5-HT1A receptor activation blocks AGS in Fmr1 knockout mice, we performed a dose-response experiment to evaluate DPT's engagement of 5-HT1A receptors in vivo. DPT elicited 5-HT1A-dependent effects only at doses greater than 10 mg/kg, further supporting that DPT's antiepileptic effects were not 5-HT1A-mediated. We also observed that the selective sigma1 receptor antagonist, NE-100, did not impact DPT's antiepileptic effects, suggesting DPT engagement of sigma1 receptors was not a crucial mechanism. Separately, we observed that DPT and NE-100 at high doses caused convulsions on their own that were qualitatively distinct from AGS. In conclusion, DPT dose-dependently blocked AGS in Fmr1 knockout mice, but neither serotonin nor sigma1 receptor antagonists prevented this action. Thus, DPT might have neurotherapeutic effects independent of its serotonergic psychedelic properties. However, DPT also caused seizures at high doses, showing that DPT has complex dose-dependent in vivo polypharmacology.
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Affiliation(s)
- Richa Tyagi
- Department of Pharmaceutical
Sciences, College of Pharmacy, Mercer University, 3001 Mercer University Drive, Atlanta, Georgia 30341, United States
| | - Tanishka S. Saraf
- Department of Pharmaceutical
Sciences, College of Pharmacy, Mercer University, 3001 Mercer University Drive, Atlanta, Georgia 30341, United States
| | - Clinton E. Canal
- Department of Pharmaceutical
Sciences, College of Pharmacy, Mercer University, 3001 Mercer University Drive, Atlanta, Georgia 30341, United States
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5
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Senapati S, Park PSH. Understanding the Rhodopsin Worldview Through Atomic Force Microscopy (AFM): Structure, Stability, and Activity Studies. CHEM REC 2023; 23:e202300113. [PMID: 37265335 PMCID: PMC10908267 DOI: 10.1002/tcr.202300113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Revised: 05/12/2023] [Indexed: 06/03/2023]
Abstract
Rhodopsin is a G protein-coupled receptor (GPCR) present in the rod outer segment (ROS) of photoreceptor cells that initiates the phototransduction cascade required for scotopic vision. Due to the remarkable advancements in technological tools, the chemistry of rhodopsin has begun to unravel especially over the past few decades, but mostly at the ensemble scale. Atomic force microscopy (AFM) is a tool capable of providing critical information from a single-molecule point of view. In this regard, to bolster our understanding of rhodopsin at the nanoscale level, AFM-based imaging, force spectroscopy, and nano-indentation techniques were employed on ROS disc membranes containing rhodopsin, isolated from vertebrate species both in normal and diseased states. These AFM studies on samples from native retinal tissue have provided fundamental insights into the structure and function of rhodopsin under normal and dysfunctional states. We review here the findings from these AFM studies that provide important insights on the supramolecular organization of rhodopsin within the membrane and factors that contribute to this organization, the molecular interactions stabilizing the structure of the receptor and factors that can modify those interactions, and the mechanism underlying constitutive activity in the receptor that can cause disease.
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Affiliation(s)
- Subhadip Senapati
- Department of Ophthalmology and Visual Sciences, Case Western Reserve University, Cleveland, OH 44106, USA
- Prayoga Institute of Education Research, Bengaluru, KA 560116, India
| | - Paul S-H Park
- Department of Ophthalmology and Visual Sciences, Case Western Reserve University, Cleveland, OH 44106, USA
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6
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Huang SM, Xiong MY, Liu L, Mu J, Wang MW, Jia YL, Cai K, Tie L, Zhang C, Cao S, Wen X, Wang JL, Guo SC, Li Y, Qu CX, He QT, Cai BY, Xue C, Gan S, Xie Y, Cong X, Yang Z, Kong W, Li S, Li Z, Xiao P, Yang F, Yu X, Guan YF, Zhang X, Liu Z, Yang BX, Du Y, Sun JP. Single hormone or synthetic agonist induces G s/G i coupling selectivity of EP receptors via distinct binding modes and propagating paths. Proc Natl Acad Sci U S A 2023; 120:e2216329120. [PMID: 37478163 PMCID: PMC10372679 DOI: 10.1073/pnas.2216329120] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Accepted: 05/18/2023] [Indexed: 07/23/2023] Open
Abstract
To accomplish concerted physiological reactions, nature has diversified functions of a single hormone at at least two primary levels: 1) Different receptors recognize the same hormone, and 2) different cellular effectors couple to the same hormone-receptor pair [R.P. Xiao, Sci STKE 2001, re15 (2001); L. Hein, J. D. Altman, B.K. Kobilka, Nature 402, 181-184 (1999); Y. Daaka, L. M. Luttrell, R. J. Lefkowitz, Nature 390, 88-91 (1997)]. Not only these questions lie in the heart of hormone actions and receptor signaling but also dissecting mechanisms underlying these questions could offer therapeutic routes for refractory diseases, such as kidney injury (KI) or X-linked nephrogenic diabetes insipidus (NDI). Here, we identified that Gs-biased signaling, but not Gi activation downstream of EP4, showed beneficial effects for both KI and NDI treatments. Notably, by solving Cryo-electron microscope (cryo-EM) structures of EP3-Gi, EP4-Gs, and EP4-Gi in complex with endogenous prostaglandin E2 (PGE2)or two synthetic agonists and comparing with PGE2-EP2-Gs structures, we found that unique primary sequences of prostaglandin E2 receptor (EP) receptors and distinct conformational states of the EP4 ligand pocket govern the Gs/Gi transducer coupling selectivity through different structural propagation paths, especially via TM6 and TM7, to generate selective cytoplasmic structural features. In particular, the orientation of the PGE2 ω-chain and two distinct pockets encompassing agonist L902688 of EP4 were differentiated by their Gs/Gi coupling ability. Further, we identified common and distinct features of cytoplasmic side of EP receptors for Gs/Gi coupling and provide a structural basis for selective and biased agonist design of EP4 with therapeutic potential.
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Affiliation(s)
- Shen-Ming Huang
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, State Key Laboratory of Vascular Homeostasis and Remodeling, Peking University, Beijing100191, China
| | - Meng-Yao Xiong
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, State Key Laboratory of Vascular Homeostasis and Remodeling, Peking University, Beijing100191, China
- Department of Pharmacology, School of Basic Medical Sciences, State Key Laboratory of Vascular Homeostasis and Remodeling, Peking University, Beijing100191, China
| | - Lei Liu
- Key Laboratory Experimental Teratology of the Ministry of Education, Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, Jinan, Shandong250012, China
| | - Jianqiang Mu
- Department of Immunology and Microbiology, School of Life Sciences, Southern University of Science and Technology, Shenzhen, Guangdong518055, China
| | - Ming-Wei Wang
- Key Laboratory Experimental Teratology of the Ministry of Education, Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, Jinan, Shandong250012, China
| | - Ying-Li Jia
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, State Key Laboratory of Vascular Homeostasis and Remodeling, Peking University, Beijing100191, China
| | - Kui Cai
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, State Key Laboratory of Vascular Homeostasis and Remodeling, Peking University, Beijing100191, China
| | - Lu Tie
- Department of Pharmacology, School of Basic Medical Sciences, State Key Laboratory of Vascular Homeostasis and Remodeling, Peking University, Beijing100191, China
| | - Chao Zhang
- Key Laboratory Experimental Teratology of the Ministry of Education, Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, Jinan, Shandong250012, China
| | - Sheng Cao
- School of Medicine, Kobilka Institute of Innovative Drug Discovery, Chinese University of Hong Kong, Shenzhen, Guangdong518172, China
| | - Xin Wen
- Key Laboratory Experimental Teratology of the Ministry of Education, Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, Jinan, Shandong250012, China
| | - Jia-Le Wang
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, State Key Laboratory of Vascular Homeostasis and Remodeling, Peking University, Beijing100191, China
| | - Sheng-Chao Guo
- Key Laboratory Experimental Teratology of the Ministry of Education, Department of Physiology, School of Basic Medical Sciences, Shandong University, Jinan, Shandong250012, China
| | - Yu Li
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, State Key Laboratory of Vascular Homeostasis and Remodeling, Peking University, Beijing100191, China
| | - Chang-Xiu Qu
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, State Key Laboratory of Vascular Homeostasis and Remodeling, Peking University, Beijing100191, China
| | - Qing-Tao He
- Key Laboratory Experimental Teratology of the Ministry of Education, Department of Physiology, School of Basic Medical Sciences, Shandong University, Jinan, Shandong250012, China
| | - Bo-Yang Cai
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, State Key Laboratory of Vascular Homeostasis and Remodeling, Peking University, Beijing100191, China
| | - Chenyang Xue
- Department of Immunology and Microbiology, School of Life Sciences, Southern University of Science and Technology, Shenzhen, Guangdong518055, China
| | - Shiyi Gan
- School of Medicine, Kobilka Institute of Innovative Drug Discovery, Chinese University of Hong Kong, Shenzhen, Guangdong518172, China
| | - Yihe Xie
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, State Key Laboratory of Vascular Homeostasis and Remodeling, Peking University, Beijing100191, China
| | - Xin Cong
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, State Key Laboratory of Vascular Homeostasis and Remodeling, Peking University, Beijing100191, China
| | - Zhao Yang
- Key Laboratory Experimental Teratology of the Ministry of Education, Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, Jinan, Shandong250012, China
| | - Wei Kong
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, State Key Laboratory of Vascular Homeostasis and Remodeling, Peking University, Beijing100191, China
| | - Shuo Li
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, State Key Laboratory of Vascular Homeostasis and Remodeling, Peking University, Beijing100191, China
| | - Zijian Li
- Department of Cardiology, Institute of Vascular Medicine, Peking University Third Hospital, Research, Beijing100191, China
- Beijing Key Laboratory of Cardiovascular Receptors Research, Peking University, Beijing100191, P. R. China
| | - Peng Xiao
- Key Laboratory Experimental Teratology of the Ministry of Education, Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, Jinan, Shandong250012, China
| | - Fan Yang
- Key Laboratory Experimental Teratology of the Ministry of Education, Department of Physiology, School of Basic Medical Sciences, Shandong University, Jinan, Shandong250012, China
- Advanced Medical Research Institute, Cheeloo College of Medicine, Shandong University, Jinan, Shandong250012, China
| | - Xiao Yu
- Key Laboratory Experimental Teratology of the Ministry of Education, Department of Physiology, School of Basic Medical Sciences, Shandong University, Jinan, Shandong250012, China
| | - You-Fei Guan
- Advanced Institute for Medical Sciences, Dalian Medical University, Dalian116044, China
| | - Xiaoyan Zhang
- Advanced Institute for Medical Sciences, Dalian Medical University, Dalian116044, China
| | - Zhongmin Liu
- Department of Immunology and Microbiology, School of Life Sciences, Southern University of Science and Technology, Shenzhen, Guangdong518055, China
| | - Bao-Xue Yang
- Department of Pharmacology, School of Basic Medical Sciences, State Key Laboratory of Vascular Homeostasis and Remodeling, Peking University, Beijing100191, China
| | - Yang Du
- School of Medicine, Kobilka Institute of Innovative Drug Discovery, Chinese University of Hong Kong, Shenzhen, Guangdong518172, China
| | - Jin-Peng Sun
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, State Key Laboratory of Vascular Homeostasis and Remodeling, Peking University, Beijing100191, China
- Key Laboratory Experimental Teratology of the Ministry of Education, Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, Jinan, Shandong250012, China
- Beijing Key Laboratory of Cardiovascular Receptors Research, Peking University, Beijing100191, P. R. China
- Advanced Medical Research Institute, Cheeloo College of Medicine, Shandong University, Jinan, Shandong250012, China
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7
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Han J, Zhang J, Nazarova AL, Bernhard SM, Krumm BE, Zhao L, Lam JH, Rangari VA, Majumdar S, Nichols DE, Katritch V, Yuan P, Fay JF, Che T. Ligand and G-protein selectivity in the κ-opioid receptor. Nature 2023; 617:417-425. [PMID: 37138078 PMCID: PMC10172140 DOI: 10.1038/s41586-023-06030-7] [Citation(s) in RCA: 24] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2022] [Accepted: 03/29/2023] [Indexed: 05/05/2023]
Abstract
The κ-opioid receptor (KOR) represents a highly desirable therapeutic target for treating not only pain but also addiction and affective disorders1. However, the development of KOR analgesics has been hindered by the associated hallucinogenic side effects2. The initiation of KOR signalling requires the Gi/o-family proteins including the conventional (Gi1, Gi2, Gi3, GoA and GoB) and nonconventional (Gz and Gg) subtypes. How hallucinogens exert their actions through KOR and how KOR determines G-protein subtype selectivity are not well understood. Here we determined the active-state structures of KOR in a complex with multiple G-protein heterotrimers-Gi1, GoA, Gz and Gg-using cryo-electron microscopy. The KOR-G-protein complexes are bound to hallucinogenic salvinorins or highly selective KOR agonists. Comparisons of these structures reveal molecular determinants critical for KOR-G-protein interactions as well as key elements governing Gi/o-family subtype selectivity and KOR ligand selectivity. Furthermore, the four G-protein subtypes display an intrinsically different binding affinity and allosteric activity on agonist binding at KOR. These results provide insights into the actions of opioids and G-protein-coupling specificity at KOR and establish a foundation to examine the therapeutic potential of pathway-selective agonists of KOR.
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Affiliation(s)
- Jianming Han
- Department of Anesthesiology, Washington University in St Louis, St Louis, MO, USA
- Center for Clinical Pharmacology, University of Health Sciences and Pharmacy in St Louis and Washington University School of Medicine, St Louis, MO, USA
| | - Jingying Zhang
- Department of Cell Biology and Physiology, Washington University School of Medicine, St Louis, MO, USA
- Center for the Investigation of Membrane Excitability Diseases, Washington University School of Medicine, St Louis, MO, USA
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Antonina L Nazarova
- Department of Quantitative and Computational Biology, University of Southern California, Los Angeles, CA, USA
- Department of Chemistry, University of Southern California, Los Angeles, CA, USA
- Center for New Technologies in Drug Discovery and Development, Bridge Institute, Michelson Center for Convergent Biosciences, University of Southern California, Los Angeles, CA, USA
| | - Sarah M Bernhard
- Department of Anesthesiology, Washington University in St Louis, St Louis, MO, USA
- Center for Clinical Pharmacology, University of Health Sciences and Pharmacy in St Louis and Washington University School of Medicine, St Louis, MO, USA
| | - Brian E Krumm
- Department of Pharmacology, University of North Carolina School of Medicine, Chapel Hill, NC, USA
| | - Lei Zhao
- Department of Anesthesiology, Washington University in St Louis, St Louis, MO, USA
| | - Jordy Homing Lam
- Department of Quantitative and Computational Biology, University of Southern California, Los Angeles, CA, USA
- Department of Chemistry, University of Southern California, Los Angeles, CA, USA
- Center for New Technologies in Drug Discovery and Development, Bridge Institute, Michelson Center for Convergent Biosciences, University of Southern California, Los Angeles, CA, USA
| | - Vipin A Rangari
- Center for Clinical Pharmacology, University of Health Sciences and Pharmacy in St Louis and Washington University School of Medicine, St Louis, MO, USA
| | - Susruta Majumdar
- Department of Anesthesiology, Washington University in St Louis, St Louis, MO, USA
- Center for Clinical Pharmacology, University of Health Sciences and Pharmacy in St Louis and Washington University School of Medicine, St Louis, MO, USA
- Washington University Pain Center, Washington University in St Louis, St Louis, MO, USA
| | - David E Nichols
- Division of Chemical Biology and Medicinal Chemistry, Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, NC, USA
| | - Vsevolod Katritch
- Department of Quantitative and Computational Biology, University of Southern California, Los Angeles, CA, USA
- Department of Chemistry, University of Southern California, Los Angeles, CA, USA
- Center for New Technologies in Drug Discovery and Development, Bridge Institute, Michelson Center for Convergent Biosciences, University of Southern California, Los Angeles, CA, USA
| | - Peng Yuan
- Department of Cell Biology and Physiology, Washington University School of Medicine, St Louis, MO, USA
- Center for the Investigation of Membrane Excitability Diseases, Washington University School of Medicine, St Louis, MO, USA
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Jonathan F Fay
- Department of Biochemistry and Molecular Biology, University of Maryland Baltimore, Baltimore, MD, USA.
| | - Tao Che
- Department of Anesthesiology, Washington University in St Louis, St Louis, MO, USA.
- Center for Clinical Pharmacology, University of Health Sciences and Pharmacy in St Louis and Washington University School of Medicine, St Louis, MO, USA.
- Washington University Pain Center, Washington University in St Louis, St Louis, MO, USA.
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8
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Kim KM. Unveiling the Differences in Signaling and Regulatory Mechanisms between Dopamine D2 and D3 Receptors and Their Impact on Behavioral Sensitization. Int J Mol Sci 2023; 24:ijms24076742. [PMID: 37047716 PMCID: PMC10095578 DOI: 10.3390/ijms24076742] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Revised: 03/25/2023] [Accepted: 03/28/2023] [Indexed: 04/09/2023] Open
Abstract
Dopamine receptors are classified into five subtypes, with D2R and D3R playing a crucial role in regulating mood, motivation, reward, and movement. Whereas D2R are distributed widely across the brain, including regions responsible for motor functions, D3R are primarily found in specific areas related to cognitive and emotional functions, such as the nucleus accumbens, limbic system, and prefrontal cortex. Despite their high sequence homology and similar signaling pathways, D2R and D3R have distinct regulatory properties involving desensitization, endocytosis, posttranslational modification, and interactions with other cellular components. In vivo, D3R is closely associated with behavioral sensitization, which leads to increased dopaminergic responses. Behavioral sensitization is believed to result from D3R desensitization, which removes the inhibitory effect of D3R on related behaviors. Whereas D2R maintains continuous signal transduction through agonist-induced receptor phosphorylation, arrestin recruitment, and endocytosis, which recycle and resensitize desensitized receptors, D3R rarely undergoes agonist-induced endocytosis and instead is desensitized after repeated agonist exposure. In addition, D3R undergoes more extensive posttranslational modifications, such as glycosylation and palmitoylation, which are needed for its desensitization. Overall, a series of biochemical settings more closely related to D3R could be linked to D3R-mediated behavioral sensitization.
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Affiliation(s)
- Kyeong-Man Kim
- Department of Pharmacology, College of Pharmacy, Chonnam National University, Gwang-Ju 61186, Republic of Korea
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9
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Krumm BE, DiBerto JF, Olsen RHJ, Kang HJ, Slocum ST, Zhang S, Strachan RT, Huang XP, Slosky LM, Pinkerton AB, Barak LS, Caron MG, Kenakin T, Fay JF, Roth BL. Neurotensin Receptor Allosterism Revealed in Complex with a Biased Allosteric Modulator. Biochemistry 2023; 62:1233-1248. [PMID: 36917754 DOI: 10.1021/acs.biochem.3c00029] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/16/2023]
Abstract
The NTSR1 neurotensin receptor (NTSR1) is a G protein-coupled receptor (GPCR) found in the brain and peripheral tissues with neurotensin (NTS) being its endogenous peptide ligand. In the brain, NTS modulates dopamine neuronal activity, induces opioid-independent analgesia, and regulates food intake. Recent studies indicate that biasing NTSR1 toward β-arrestin signaling can attenuate the actions of psychostimulants and other drugs of abuse. Here, we provide the cryoEM structures of NTSR1 ternary complexes with heterotrimeric Gq and GoA with and without the brain-penetrant small-molecule SBI-553. In functional studies, we discovered that SBI-553 displays complex allosteric actions exemplified by negative allosteric modulation for G proteins that are Gα subunit selective and positive allosteric modulation and agonism for β-arrestin translocation at NTSR1. Detailed structural analysis of the allosteric binding site illuminated the structural determinants for biased allosteric modulation of SBI-553 on NTSR1.
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Affiliation(s)
- Brian E Krumm
- Department of Pharmacology, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, North Carolina 27599-7365, United States
| | - Jeffrey F DiBerto
- Department of Pharmacology, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, North Carolina 27599-7365, United States
| | - Reid H J Olsen
- Department of Pharmacology, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, North Carolina 27599-7365, United States
| | - Hye Jin Kang
- Department of Pharmacology, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, North Carolina 27599-7365, United States
- National Institute of Mental Health Psychoactive Drug Screening Program (NIMH PDSP), School of Medicine, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, North Carolina 27599-7365, United States
| | - Samuel T Slocum
- Department of Pharmacology, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, North Carolina 27599-7365, United States
- National Institute of Mental Health Psychoactive Drug Screening Program (NIMH PDSP), School of Medicine, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, North Carolina 27599-7365, United States
| | - Shicheng Zhang
- Department of Pharmacology, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, North Carolina 27599-7365, United States
| | - Ryan T Strachan
- Department of Pharmacology, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, North Carolina 27599-7365, United States
| | - Xi-Ping Huang
- Department of Pharmacology, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, North Carolina 27599-7365, United States
- National Institute of Mental Health Psychoactive Drug Screening Program (NIMH PDSP), School of Medicine, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, North Carolina 27599-7365, United States
| | - Lauren M Slosky
- Department of Pharmacology, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Anthony B Pinkerton
- Conrad Prebys Center for Chemical Genomics at Sanford Burnham Prebys Medical Discovery Institute, La Jolla, California 92037, United States
| | - Lawrence S Barak
- Department of Cell Biology, Duke University, Durham, North Carolina 27710, United States
| | - Marc G Caron
- Department of Cell Biology, Duke University, Durham, North Carolina 27710, United States
- Departments of Medicine and Neurobiology, Duke University, Durham, North Carolina 27710, United States
| | - Terry Kenakin
- Department of Pharmacology, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, North Carolina 27599-7365, United States
| | - Jonathan F Fay
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, North Carolina 27599, United States
| | - Bryan L Roth
- Department of Pharmacology, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, North Carolina 27599-7365, United States
- National Institute of Mental Health Psychoactive Drug Screening Program (NIMH PDSP), School of Medicine, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, North Carolina 27599-7365, United States
- Division of Chemical Biology and Medicinal Chemistry, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-7360, United States
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10
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Frankle WG, Himes M, Mason NS, Mathis CA, Narendran R. Prefrontal and Striatal Dopamine Release Are Inversely Correlated in Schizophrenia. Biol Psychiatry 2022; 92:791-799. [PMID: 35791965 DOI: 10.1016/j.biopsych.2022.05.009] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Revised: 04/19/2022] [Accepted: 05/02/2022] [Indexed: 11/17/2022]
Abstract
BACKGROUND The dopamine (DA) hypothesis postulates hyperactivity of subcortical DA transmission and hypoactivity of cortical DA in schizophrenia (SCH). Positron emission tomography provides the ability to assess this hypothesis in humans. However, no studies have examined the relationship between cortical DA and striatal DA in this illness. METHODS D2/3 receptor radiotracer [11C]FLB457 BPND (binding potential relative to nondisplaceable uptake) was measured in 14 off-medication subjects with SCH and 14 healthy control (HC) subjects at baseline and after the administration of 0.5 mg/kg oral d-amphetamine. The amphetamine-induced change in BPND (ΔBPND) was calculated as the difference between BPND in the postamphetamine condition and BPND in the baseline condition and expressed as a percentage of BPND at baseline. DA release in the striatum using the radiotracer [11C]NPA was also measured in these subjects. RESULTS [11C]FLB457 ΔBPND was greater in the HC group compared with the SCH group (F1,26 = 5.7; p = .02) with significant differences in [11C]FLB457 ΔBPND seen across cortical brain regions. Only in the SCH group was a significant negative correlation observed between [11C]FLB457 ΔBPND in the dorsolateral prefrontal cortex and [11C]NPA ΔBPND in the dorsal caudate (r = -0.71, p = .005). CONCLUSIONS Subjects with SCH demonstrated deficits of DA release in cortical brain regions relative to HC subjects. Examining both cortical and striatal DA release in the same subjects demonstrated an inverse relationship between cortical DA release and striatal DA release in SCH not present in HC subjects, providing support for the current DA hypothesis of SCH.
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Affiliation(s)
- W Gordon Frankle
- Department of Psychiatry, NYU Langone Medical Center, New York, New York.
| | - Michael Himes
- Department of Psychiatry, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - N Scott Mason
- Department of Radiology, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Chester A Mathis
- Department of Radiology, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Rajesh Narendran
- Department of Psychiatry, University of Pittsburgh, Pittsburgh, Pennsylvania; Department of Radiology, University of Pittsburgh, Pittsburgh, Pennsylvania
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11
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Grätz L, Müller C, Pegoli A, Schindler L, Bernhardt G, Littmann T. Insertion of Nanoluc into the Extracellular Loops as a Complementary Method To Establish BRET-Based Binding Assays for GPCRs. ACS Pharmacol Transl Sci 2022; 5:1142-1155. [PMID: 36407949 PMCID: PMC9667534 DOI: 10.1021/acsptsci.2c00162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Indexed: 11/13/2022]
Abstract
Luminescence-based techniques play an increasingly important role in all areas of biochemical research, including investigations on G protein-coupled receptors (GPCRs). One quite recent and popular addition has been made by introducing bioluminescence resonance energy transfer (BRET)-based binding assays for GPCRs, which are based on the fusion of nanoluciferase (Nluc) to the N-terminus of the receptor and the occurring energy transfer via BRET to a bound fluorescent ligand. However, being based on BRET, the technique is strongly dependent on the distance/orientation between the luciferase and the fluorescent ligand. Here we describe an alternative strategy to establish BRET-based binding assays for GPCRs, where the N-terminal fusion of Nluc did not result in functioning test systems with our fluorescent ligands (e.g., for the neuropeptide Y Y1 receptor (Y1R) and the neurotensin receptor type 1 (NTS1R)). Instead, we introduced Nluc into their second extracellular loop and we obtained binding data for the fluorescent ligands and reported standard ligands (in saturation and competition binding experiments, respectively) comparable to data from the literature. The strategy was transferred to the angiotensin II receptor type 1 (AT1R) and the M1 muscarinic acetylcholine receptor (M1R), which led to affinity estimates comparable to data from radioligand binding experiments. Additionally, an analysis of the binding kinetics of all fluorescent ligands at their respective target was performed using the newly described receptor/Nluc-constructs.
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Affiliation(s)
| | - Christoph Müller
- Institute of Pharmacy, Faculty of Chemistry and Pharmacy, University of Regensburg, Universitätsstrasse 31, D-93053 Regensburg, Germany
| | | | - Lisa Schindler
- Institute of Pharmacy, Faculty of Chemistry and Pharmacy, University of Regensburg, Universitätsstrasse 31, D-93053 Regensburg, Germany
| | - Günther Bernhardt
- Institute of Pharmacy, Faculty of Chemistry and Pharmacy, University of Regensburg, Universitätsstrasse 31, D-93053 Regensburg, Germany
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12
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Maudsley S, Walter D, Schrauwen C, Van Loon N, Harputluoğlu İ, Lenaerts J, McDonald P. Intersection of the Orphan G Protein-Coupled Receptor, GPR19, with the Aging Process. Int J Mol Sci 2022; 23:ijms232113598. [PMID: 36362387 PMCID: PMC9653598 DOI: 10.3390/ijms232113598] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Revised: 11/02/2022] [Accepted: 11/03/2022] [Indexed: 11/09/2022] Open
Abstract
G protein-coupled receptors (GPCRs) represent one of the most functionally diverse classes of transmembrane proteins. GPCRs and their associated signaling systems have been linked to nearly every physiological process. They also constitute nearly 40% of the current pharmacopeia as direct targets of remedial therapies. Hence, their place as a functional nexus in the interface between physiological and pathophysiological processes suggests that GPCRs may play a central role in the generation of nearly all types of human disease. Perhaps one mechanism through which GPCRs can mediate this pivotal function is through the control of the molecular aging process. It is now appreciated that, indeed, many human disorders/diseases are induced by GPCR signaling processes linked to pathological aging. Here we discuss one such novel member of the GPCR family, GPR19, that may represent an important new target for novel remedial strategies for the aging process. The molecular signaling pathways (metabolic control, circadian rhythm regulation and stress responsiveness) associated with this recently characterized receptor suggest an important role in aging-related disease etiology.
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Affiliation(s)
- Stuart Maudsley
- Receptor Biology Lab, University of Antwerp, 2610 Antwerpen, Belgium
- Correspondence:
| | - Deborah Walter
- Receptor Biology Lab, University of Antwerp, 2610 Antwerpen, Belgium
| | - Claudia Schrauwen
- Receptor Biology Lab, University of Antwerp, 2610 Antwerpen, Belgium
| | - Nore Van Loon
- Receptor Biology Lab, University of Antwerp, 2610 Antwerpen, Belgium
| | - İrem Harputluoğlu
- Receptor Biology Lab, University of Antwerp, 2610 Antwerpen, Belgium
| | - Julia Lenaerts
- Receptor Biology Lab, University of Antwerp, 2610 Antwerpen, Belgium
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13
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Erritzoe D, Godlewska BR, Rizzo G, Searle GE, Agnorelli C, Lewis Y, Ashok AH, Colasanti A, Boura I, Farrell C, Parfitt H, Howes O, Passchier J, Gunn RN, Politis M, Nutt DJ, Cowen PJ, Knudsen GM, Rabiner EA. Brain Serotonin Release Is Reduced in Patients With Depression: A [ 11C]Cimbi-36 Positron Emission Tomography Study With a d-Amphetamine Challenge. Biol Psychiatry 2022:S0006-3223(22)01704-8. [PMID: 36635177 DOI: 10.1016/j.biopsych.2022.10.012] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Revised: 10/03/2022] [Accepted: 10/21/2022] [Indexed: 01/14/2023]
Abstract
BACKGROUND The serotonin hypothesis of depression proposes that diminished serotonergic (5-HT) neurotransmission is causal in the pathophysiology of the disorder. Although the hypothesis is over 50 years old, there is no firm in vivo evidence for diminished 5-HT neurotransmission. We recently demonstrated that the 5-HT2A receptor agonist positron emission tomography (PET) radioligand [11C]Cimbi-36 is sensitive to increases in extracellular 5-HT induced by an acute d-amphetamine challenge. Here we applied [11C]Cimbi-36 PET to compare brain 5-HT release capacity in patients experiencing a major depressive episode (MDE) to that of healthy control subjects (HCs) without depression. METHODS Seventeen antidepressant-free patients with MDE (3 female/14 male, mean age 44 ± 13 years, Hamilton Depression Rating Scale score 21 ± 4 [range 16-30]) and 20 HCs (3 female/17 male, mean age 32 ± 9 years) underwent 90-minute dynamic [11C]Cimbi-36 PET before and 3 hours after a 0.5-mg/kg oral dose of d-amphetamine. Frontal cortex (main region of interest) 5-HT2A receptor nondisplaceable binding was calculated from kinetic analysis using the multilinear analysis-1 approach with the cerebellum as the reference region. RESULTS Following d-amphetamine administration, frontal nondisplaceable binding potential (BPND) was significantly reduced in the HC group (1.04 ± 0.31 vs. 0.87 ± 0.24, p < .001) but not in the MDE group (0.97 ± 0.25 vs. 0.92 ± 0.22, not significant). ΔBPND of the MDE group was significantly lower than that of the HC group (HC: 15% ± 14% vs. MDE: 6.5% ± 20%, p = .041). CONCLUSIONS This first direct assessment of 5-HT release capacity in people with depression provides clear evidence for dysfunctional serotonergic neurotransmission in depression by demonstrating reduced 5-HT release capacity in patients experiencing an MDE.
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Affiliation(s)
- David Erritzoe
- Division of Psychiatry, Department of Brain Sciences, Imperial College London, London, United Kingdom.
| | - Beata R Godlewska
- Department of Psychiatry, University of Oxford, Oxford, United Kingdom
| | | | | | - Claudio Agnorelli
- Division of Psychiatry, Department of Brain Sciences, Imperial College London, London, United Kingdom; Department of Molecular Medicine, University of Siena, Siena, Italy
| | | | - Abhishekh H Ashok
- Department of Psychosis Studies, King's College London, London, United Kingdom; Department of Radiology, University of Cambridge & Addenbrooke's Hospital, Cambridge, United Kingdom
| | | | - Iro Boura
- Parkinson Foundation Centre of Excellence, King's College London, London, United Kingdom
| | - Chloe Farrell
- Parkinson Foundation Centre of Excellence, King's College London, London, United Kingdom
| | - Hollie Parfitt
- Division of Psychiatry, Department of Brain Sciences, Imperial College London, London, United Kingdom
| | - Oliver Howes
- Department of Psychosis Studies, King's College London, London, United Kingdom
| | | | | | - Marios Politis
- Neurodegeneration Imaging Group, University of Exeter, Exeter, United Kingdom
| | - David J Nutt
- Division of Psychiatry, Department of Brain Sciences, Imperial College London, London, United Kingdom
| | - Philip J Cowen
- Department of Psychiatry, University of Oxford, Oxford, United Kingdom
| | - Gitte M Knudsen
- Neurobiology Research Unit, University Hospital Rigshospitalet and Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Eugenii A Rabiner
- Invicro, London, United Kingdom; Department of Neuroimaging, King's College London, London, United Kingdom
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14
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Saumell-Esnaola M, Elejaga-Jimeno A, Echeazarra L, Borrega-Román L, Barrondo S, López de Jesús M, González-Burguera I, Gómez-Caballero A, Goicolea MA, Sallés J, García del Caño G. Design and validation of recombinant protein standards for quantitative Western blot analysis of cannabinoid CB1 receptor density in cell membranes: an alternative to radioligand binding methods. Microb Cell Fact 2022; 21:192. [PMID: 36109736 PMCID: PMC9479267 DOI: 10.1186/s12934-022-01914-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Accepted: 08/27/2022] [Indexed: 11/16/2022] Open
Abstract
Background Replacement of radioligand binding assays with antibody-antigen interaction-based approaches for quantitative analysis of G protein-coupled receptor (GPCR) levels requires the use of purified protein standards containing the antigen. GPCRs in general and cannabinoid CB1 receptor in particular show a progressive tendency to aggregate and precipitate in aqueous solution outside of their biological context due to the low solubility that the hydrophobic nature imprinted by their seven transmembrane domains. This renders full-length recombinant GPCRs useless for analytical purposes, a problem that can be overcome by engineering soluble recombinant fragments of the receptor containing the antigen. Results Here we generated highly soluble and stable recombinant protein constructs GST-CB1414–472 and GST-CB1414-442 containing much of the human CB1 receptor C-terminal tail for use as standard and negative control, respectively, in quantitative Western blot analysis of CB1 receptor expression on crude synaptosomes of the adult rat brain cortex. To this end we used three different antibodies, all raised against a peptide comprising the C-terminal residues 443–473 of the mouse CB1 receptor that corresponds to residues 442–472 in the human homolog. Estimated values of CB1 receptor density obtained by quantitative Western blot were of the same order of magnitude but slightly higher than values obtained by the radioligand saturation binding assay. Conclusions Collectively, here we provide a suitable Western blot-based design as a simple, cost-effective and radioactivity-free alternative for the quantitative analysis of CB1 receptor expression, and potentially of any GPCR, in a variety of biological samples. The discrepancies between the results obtained by quantitative Western blot and radioligand saturation binding techniques are discussed in the context of their particular theoretical bases and methodological constraints. Supplementary Information The online version contains supplementary material available at 10.1186/s12934-022-01914-1.
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15
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Glatfelter GC, Pham DNK, Walther D, Golen JA, Chadeayne AR, Baumann MH, Manke DR. Synthesis, Structural Characterization, and Pharmacological Activity of Novel Quaternary Salts of 4-Substituted Tryptamines. ACS OMEGA 2022; 7:24888-24894. [PMID: 35874244 PMCID: PMC9301952 DOI: 10.1021/acsomega.2c03476] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Aeruginascin (4-phosphoryloxy-N,N,N-trimethyltryptammonium) is an analogue of psilocybin (4-phosphoryloxy-N,N-dimethyltryptamine) that has been identified in several species of psilocybin-containing mushrooms. Our team previously reported the synthesis, structural characterization, and biological activity of the putative metabolite of aeruginascin (4-hydroxy-N,N,N-trimethyltryptammonium; 4-HO-TMT) and its potential prodrug (4-acetoxy-N,N,N-trimethyltryptammonium; 4-AcO-TMT). Here, we report the synthesis, structural characterization, and pharmacological activity of several quaternary tryptammonium analogues of 4-HO-TMT and 4-AcO-TMT, namely, 4-hydroxy-N,N-dimethyl-N-ethyltryptammonium (4-HO-DMET), 4-hydroxy-N,N-dimethyl-N-n-propyltryptammonium (4-HO-DMPT), and 4-hydroxy-N,N-dimethyl-N-isopropyltryptammonium (4-HO-DMiPT), as well as their hypothesized prodrugs 4-acetoxy-N,N-dimethyl-N-ethyltryptammonium (4-AcO-DMET), 4-acetoxy-N,N-dimethyl-N-n-propyltryptammonium (4-AcO-DMPT), and 4-acetoxy-N,N-dimethyl-N-isopropyltryptammonium (4-AcO-DMiPT). Compounds were synthesized using established methods, and structures were characterized by single-crystal X-ray diffraction. Test compounds were screened for in vitro pharmacological activity at a variety of receptors and transporters to determine potential targets of action. None of the compounds exhibited measurable affinity for the serotonin 2A receptor (5-HT2A), but several analogues had low micromolar affinity (K i) for the serotonin 1D receptor (5-HT1D) and serotonin 2B receptor (5-HT2B), where they appeared to be weak partial agonists with low micromolar potencies. Importantly, 4-HO-DMET, 4-HO-DMPT, and 4-HO-DMiPT displayed sub-micromolar affinity for the serotonin transporter (SERT; 370-890 nM). The same 4-hydroxy analogues had low to sub-micromolar potencies (IC50) for inhibition of 5-HT uptake at SERT in transfected cells (3.3-12.3 μM) and rat brain tissue (0.31-3.5 μM). Overall, our results show that quaternary tryptammonium analogues do not target 5-HT2A sites, suggesting the compounds lack psychedelic-like subjective effects. However, certain 4-hydroxy quaternary tryptammonium analogues may provide novel templates for exploring structure-activity relationships for selective actions at SERT.
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Affiliation(s)
- Grant C. Glatfelter
- Designer
Drug Research Unit, National Institute on
Drug Abuse, Intramural Research Program, Baltimore, Maryland 21224 United States
| | - Duyen N. K. Pham
- Department
of Chemistry and Biochemistry, University
of Massachusetts Dartmouth, North Dartmouth, Massachusetts 02747, United States
| | - Donna Walther
- Designer
Drug Research Unit, National Institute on
Drug Abuse, Intramural Research Program, Baltimore, Maryland 21224 United States
| | - James A. Golen
- Department
of Chemistry and Biochemistry, University
of Massachusetts Dartmouth, North Dartmouth, Massachusetts 02747, United States
| | | | - Michael H. Baumann
- Designer
Drug Research Unit, National Institute on
Drug Abuse, Intramural Research Program, Baltimore, Maryland 21224 United States
| | - David R. Manke
- Department
of Chemistry and Biochemistry, University
of Massachusetts Dartmouth, North Dartmouth, Massachusetts 02747, United States
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In Silico Study of Allosteric Communication Networks in GPCR Signaling Bias. Int J Mol Sci 2022; 23:ijms23147809. [PMID: 35887157 PMCID: PMC9315799 DOI: 10.3390/ijms23147809] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Revised: 07/08/2022] [Accepted: 07/11/2022] [Indexed: 11/20/2022] Open
Abstract
Signaling bias is a promising characteristic of G protein-coupled receptors (GPCRs) as it provides the opportunity to develop more efficacious and safer drugs. This is because biased ligands can avoid the activation of pathways linked to side effects whilst still producing the desired therapeutic effect. In this respect, a deeper understanding of receptor dynamics and implicated allosteric communication networks in signaling bias can accelerate the research on novel biased drug candidates. In this review, we aim to provide an overview of computational methods and techniques for studying allosteric communication and signaling bias in GPCRs. This includes (i) the detection of allosteric communication networks and (ii) the application of network theory for extracting relevant information pipelines and highly communicated sites in GPCRs. We focus on the most recent research and highlight structural insights obtained based on the framework of allosteric communication networks and network theory for GPCR signaling bias.
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17
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Liu Z, Hruby VJ. MC4R biased signalling and the conformational basis of biological function selections. J Cell Mol Med 2022; 26:4125-4136. [PMID: 35818295 PMCID: PMC9344818 DOI: 10.1111/jcmm.17441] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2021] [Revised: 05/26/2022] [Accepted: 06/01/2022] [Indexed: 11/30/2022] Open
Abstract
The MC4R, a GPCR, has long been a major target for obesity treatment. As the most well‐studied melanocortin receptor subtype, the evolutionary knowledge pushes the drug development and structure–activity relationship (SAR) moving forward. The past decades have witnessed the evolution of scientists' view on GPCRs gradually from the control of a single canonical signalling pathway via a bilateral ‘active‐inactive’ model to a multi‐state alternative model where the ligands' binding affects the selection of the downstream signalling. This evolution brings the concept of biased signalling and the beginning of the next generation of peptide drug development, with the aim of turning from receptor subtype specificity to signalling pathway selectivity. The determination of the value structures of the MC4R revealed insights into the working mechanism of MC4R activation upon binding of agonists. However, new challenge has risen as we seek to unravel the mystery of MC4R signalling selection. Thus, more biased agonists and ligands with representative biological functions are needed to solve the rest of the puzzle.
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Affiliation(s)
- Zekun Liu
- Department of Chemistry and Biochemistry, The University of Arizona, Tucson, Arizona, USA
| | - Victor J Hruby
- Department of Chemistry and Biochemistry, The University of Arizona, Tucson, Arizona, USA
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18
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Hanson J. [G proteins: privileged transducers of 7-transmembrane spanning receptors]. Biol Aujourdhui 2022; 215:95-106. [PMID: 35275054 DOI: 10.1051/jbio/2021011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2021] [Indexed: 06/14/2023]
Abstract
G protein-coupled receptors or GPCR are the most abundant membrane receptors in our genome with around 800 members. They play an essential role in most physiological and pathophysiological phenomena. In addition, they constitute 30% of the targets of currently marketed drugs and remain an important reservoir for new innovative therapies. Their main effectors are heterotrimeric G proteins. These are composed of 3 subunits, α, β and γ, which, upon coupling with a GPCR, dissociate into Gα and Gβγ to activate numerous signaling pathways. This article describes some of the recent advances in understanding the function and role of heterotrimeric G proteins. After a short introduction to GPCRs, the history of the discovery of G proteins is briefly described. Then, the fundamental mechanisms of activation, signaling and regulation of G proteins are reviewed. New paradigms concerning intracellular signaling, specific recognition of G proteins by GPCRs as well as biased signaling are also discussed.
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Affiliation(s)
- Julien Hanson
- Laboratoire de Pharmacologie Moléculaire, GIGA-Molecular Biology of Diseases, Université de Liège, CHU, B34, Tour GIGA (+4), Avenue de l'Hôpital 11, B-4000 Liège, Belgique
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Kinetic model of GPCR-G protein interactions reveals allokairic modulation of signaling. Nat Commun 2022; 13:1202. [PMID: 35260563 PMCID: PMC8904551 DOI: 10.1038/s41467-022-28789-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2021] [Accepted: 02/09/2022] [Indexed: 11/23/2022] Open
Abstract
Established models of ternary complex formation between hormone, G protein coupled receptor (GPCR), and G protein assume that all interactions occur under equilibrium conditions. However, recent studies have established that the lifetimes of these interactions are comparable to the duration of hormone activated GPCR signaling. To simulate interactions during such non-equilibrium conditions, we propose a kinetic model wherein the receptor undergoes rate-limiting transitions between two hormone-bound active states. Simulations, using experimentally measured parameters, demonstrate transient states in ternary complex formation, and delineate the phenomenon of GPCR priming, wherein non-cognate G proteins substantially enhance cognate G protein signaling. Our model reveals that kinetic barriers of slow receptor interconversion can be overcome through allokairic modulation, a regulatory mechanism of ternary complex formation and downstream signaling. Experimentally validated kinetic simulations uncover transient enhancement of GPCR ternary complex formation by allokairic effectors.
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20
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Leysen H, Walter D, Christiaenssen B, Vandoren R, Harputluoğlu İ, Van Loon N, Maudsley S. GPCRs Are Optimal Regulators of Complex Biological Systems and Orchestrate the Interface between Health and Disease. Int J Mol Sci 2021; 22:ijms222413387. [PMID: 34948182 PMCID: PMC8708147 DOI: 10.3390/ijms222413387] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Revised: 12/08/2021] [Accepted: 12/09/2021] [Indexed: 02/06/2023] Open
Abstract
GPCRs arguably represent the most effective current therapeutic targets for a plethora of diseases. GPCRs also possess a pivotal role in the regulation of the physiological balance between healthy and pathological conditions; thus, their importance in systems biology cannot be underestimated. The molecular diversity of GPCR signaling systems is likely to be closely associated with disease-associated changes in organismal tissue complexity and compartmentalization, thus enabling a nuanced GPCR-based capacity to interdict multiple disease pathomechanisms at a systemic level. GPCRs have been long considered as controllers of communication between tissues and cells. This communication involves the ligand-mediated control of cell surface receptors that then direct their stimuli to impact cell physiology. Given the tremendous success of GPCRs as therapeutic targets, considerable focus has been placed on the ability of these therapeutics to modulate diseases by acting at cell surface receptors. In the past decade, however, attention has focused upon how stable multiprotein GPCR superstructures, termed receptorsomes, both at the cell surface membrane and in the intracellular domain dictate and condition long-term GPCR activities associated with the regulation of protein expression patterns, cellular stress responses and DNA integrity management. The ability of these receptorsomes (often in the absence of typical cell surface ligands) to control complex cellular activities implicates them as key controllers of the functional balance between health and disease. A greater understanding of this function of GPCRs is likely to significantly augment our ability to further employ these proteins in a multitude of diseases.
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Affiliation(s)
- Hanne Leysen
- Receptor Biology Lab, University of Antwerp, 2610 Wilrijk, Belgium; (H.L.); (D.W.); (B.C.); (R.V.); (İ.H.); (N.V.L.)
| | - Deborah Walter
- Receptor Biology Lab, University of Antwerp, 2610 Wilrijk, Belgium; (H.L.); (D.W.); (B.C.); (R.V.); (İ.H.); (N.V.L.)
| | - Bregje Christiaenssen
- Receptor Biology Lab, University of Antwerp, 2610 Wilrijk, Belgium; (H.L.); (D.W.); (B.C.); (R.V.); (İ.H.); (N.V.L.)
| | - Romi Vandoren
- Receptor Biology Lab, University of Antwerp, 2610 Wilrijk, Belgium; (H.L.); (D.W.); (B.C.); (R.V.); (İ.H.); (N.V.L.)
| | - İrem Harputluoğlu
- Receptor Biology Lab, University of Antwerp, 2610 Wilrijk, Belgium; (H.L.); (D.W.); (B.C.); (R.V.); (İ.H.); (N.V.L.)
- Department of Chemistry, Middle East Technical University, Çankaya, Ankara 06800, Turkey
| | - Nore Van Loon
- Receptor Biology Lab, University of Antwerp, 2610 Wilrijk, Belgium; (H.L.); (D.W.); (B.C.); (R.V.); (İ.H.); (N.V.L.)
| | - Stuart Maudsley
- Receptor Biology Lab, University of Antwerp, 2610 Wilrijk, Belgium; (H.L.); (D.W.); (B.C.); (R.V.); (İ.H.); (N.V.L.)
- Correspondence:
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21
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Chen J, Liu J, Yuan Y, Chen X, Zhang F, Pu X. Molecular Mechanisms of Diverse Activation Stimulated by Different Biased Agonists for the β2-Adrenergic Receptor. J Chem Inf Model 2021; 62:5175-5192. [PMID: 34802238 DOI: 10.1021/acs.jcim.1c01016] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
β2AR is an important drug target protein involving many diseases. Biased drugs induce specific signaling and provide additional clinical utility to optimize β2AR-based therapies. However, the biased signaling mechanism has not been elucidated. Motivated by the issue, we chose four agonists with divergent bias (balanced agonist, G-protein-biased agonist, and β-arrestin-biased agonists) and utilized Gaussian accelerated molecular dynamics simulation coupled with a dynamic network to probe the molecular mechanisms of distinct biased activation induced by the structural differences between the four agonists. Our simulations reveal that the G-protein-biased agonist induces an open conformation with the outward shifts of TM6 and TM7 for the intracellular domain, which will be beneficial to couple G protein. In contrast, the β-arrestin-biased agonists regulate an occluded conformation with a slightly outward movement of TM6 and an inward shift of TM7, which should favor β-arrestin signaling. The balanced agonist does not induce an observable outward shift for TM6 but, along with a slight tilt for TM7, leads to an inactive-like conformation. In addition, our results reveal the first time that ICL3 presents specific conformations with different agonists. The G-protein-biased agonist drives ICL3 to open so that the G protein-binding pocket can be available, while the β-arrestin-biased agonists induce ICL3 to form a closed conformation with a stable local α-helix. MM/PBSA analysis further reveals that the hydroxyl groups in the resorcinol of the G-protein-biased agonist form strong interactions with Y5.38 and S5.42, thus preventing tilting of the TM5 extracellular end. The catechol of the balanced agonist and the β-arrestin-biased ones induces the rearrangement of two hydrophobic residues F6.52 and W6.48. However, different from the balanced agonist, the ethyl substituent of β-arrestin-biased agonists forms additional hydrophobic interactions with W6.48 and F6.51 after the rearrangement, which should contribute to the β-arrestin bias. The shortest pathway analysis further reveals that the three residues Y7.43, N7.45, and N7.49 are crucial for allosterically regulating G-protein-biased signaling, while the two residues W6.48 and F6.44 make an important contribution to regulate β-arrestin-biased signaling. For the balanced agonist NE, the allosteric regulation pathway simultaneously involves the residue associated with G-protein-biased signaling like S5.46 and the residues related to β-arrestin-biased signaling like W6.48 and F6.44, thus producing unbiased signaling. The observations could advance our understanding of the biased activation mechanism on class A GPCRs and provide a useful guideline for the design of biased drugs.
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Affiliation(s)
- Jianfang Chen
- College of Chemistry, Sichuan University, Chengdu 610064, China
| | - Jiangting Liu
- College of Chemistry, Sichuan University, Chengdu 610064, China
| | - Yuan Yuan
- College of Management, Southwest University for Nationalities, Chengdu 610041, China
| | - Xin Chen
- College of Chemistry, Sichuan University, Chengdu 610064, China
| | - Fuhui Zhang
- College of Chemistry, Sichuan University, Chengdu 610064, China
| | - Xuemei Pu
- College of Chemistry, Sichuan University, Chengdu 610064, China
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22
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Slocum ST, DiBerto JF, Roth BL. Molecular insights into psychedelic drug action. J Neurochem 2021; 162:24-38. [PMID: 34797943 DOI: 10.1111/jnc.15540] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Revised: 11/11/2021] [Accepted: 11/11/2021] [Indexed: 12/14/2022]
Abstract
A confluence of factors has renewed interest in the scientific understanding and translational potential of psychedelic drugs such as lysergic acid diethylamide (LSD), mescaline, and psilocybin: the desire for additional approaches to mental health care, incremental progress in basic and clinical research, and the reconsideration and relaxation of existing drug policies. With the United States Food and Drug Administration's designation of psilocybin as a "Breakthrough Therapy" for treatment-resistant depression, a new path has been forged for the conveyance of psychedelics to the clinic. Essential to the further development of such applications, however, is a clearer understanding of how these drugs exert their effects at the molecular level. Here we review the current knowledge regarding the molecular details of psychedelic drug actions and suggest that these discoveries can facilitate new insights into their hallucinogenic and therapeutic mechanisms.
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Affiliation(s)
- Samuel T Slocum
- Department of Pharmacology, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, North Carolina, USA
| | - Jeffrey F DiBerto
- Department of Pharmacology, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, North Carolina, USA
| | - Bryan L Roth
- Department of Pharmacology, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, North Carolina, USA
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23
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Faro D, Boekhoff I, Gudermann T, Breit A. Physiological Temperature Changes Fine-Tune β 2- Adrenergic Receptor-Induced Cytosolic cAMP Accumulation. Mol Pharmacol 2021; 100:203-216. [PMID: 34158361 DOI: 10.1124/molpharm.121.000309] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Accepted: 06/04/2021] [Indexed: 11/22/2022] Open
Abstract
Norepinephrine (NE) controls many vital body functions by activating adrenergic receptors (ARs). Average core body temperature (CBT) in mice is 37°C. Of note, CBT fluctuates between 36 and 38°C within 24 hours, but little is known about the effects of CBT changes on the pharmacodynamics of NE. Here, we used Peltier element-controlled incubators and challenged murine hypothalamic mHypoA -2/10 cells with temperature changes of ±1°C. We observed enhanced NE-induced activation of a cAMP-dependent luciferase reporter at 36 compared with 38°C. mRNA analysis and subtype specific antagonists revealed that NE activates β 2- and β 3-AR in mHypoA-2/10 cells. Agonist binding to the β 2-AR was temperature insensitive, but measurements of cytosolic cAMP accumulation revealed an increase in efficacy of 45% ± 27% for NE and of 62% ± 33% for the β 2-AR-selective agonist salmeterol at 36°C. When monitoring NE-promoted cAMP efflux, we observed an increase in the absolute efflux at 36°C. However, the ratio of exported to cytosolic accumulated cAMP is higher at 38°C. We also stimulated cells with NE at 37°C and measured cAMP degradation at 36 and 38°C afterward. We observed increased cAMP degradation at 38°C, indicating enhanced phosphodiesterase activity at higher temperatures. In line with these data, NE-induced activation of the thyreoliberin promoter was found to be enhanced at 36°C. Overall, we show that physiologic temperature changes fine-tune NE-induced cAMP signaling in hypothalamic cells via β 2-AR by modulating cAMP degradation and the ratio of intra- and extracellular cAMP. SIGNIFICANCE STATEMENT: Increasing cytosolic cAMP levels by activation of G protein-coupled receptors (GPCR) such as the β 2-adrenergic receptor (AR) is essential for many body functions. Changes in core body temperature are fundamental and universal factors of mammalian life. This study provides the first data linking physiologically relevant temperature fluctuations to β 2-AR-induced cAMP signaling, highlighting a so far unappreciated role of body temperature as a modulator of the prototypic class A GPCR.
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MESH Headings
- 1-Methyl-3-isobutylxanthine/pharmacology
- ARNTL Transcription Factors/metabolism
- Aminopyridines/pharmacology
- Animals
- Cell Line
- Cyclic AMP/metabolism
- Cyclic AMP Response Element-Binding Protein/metabolism
- Cytosol/metabolism
- Forkhead Transcription Factors/metabolism
- GTP-Binding Protein alpha Subunits, Gq-G11/physiology
- GTP-Binding Protein alpha Subunits, Gs/physiology
- Hypothalamus/physiology
- Mice
- Neurons/physiology
- Norepinephrine/pharmacology
- Receptors, Adrenergic, beta-2/biosynthesis
- Receptors, Adrenergic, beta-2/physiology
- Receptors, Adrenergic, beta-3/biosynthesis
- Receptors, Adrenergic, beta-3/physiology
- STAT Transcription Factors/metabolism
- Salmeterol Xinafoate/pharmacology
- Signal Transduction/physiology
- Temperature
- Thyrotropin-Releasing Hormone/genetics
- Thyrotropin-Releasing Hormone/metabolism
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Affiliation(s)
- Dennis Faro
- Walther-Straub-Institut für Pharmakologie und Toxikologie, Ludwig-Maximilians-Universität München, München, Germany
| | - Ingrid Boekhoff
- Walther-Straub-Institut für Pharmakologie und Toxikologie, Ludwig-Maximilians-Universität München, München, Germany
| | - Thomas Gudermann
- Walther-Straub-Institut für Pharmakologie und Toxikologie, Ludwig-Maximilians-Universität München, München, Germany
| | - Andreas Breit
- Walther-Straub-Institut für Pharmakologie und Toxikologie, Ludwig-Maximilians-Universität München, München, Germany
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24
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Research Advances in Heterotrimeric G-Protein α Subunits and Uncanonical G-Protein Coupled Receptors in Plants. Int J Mol Sci 2021; 22:ijms22168678. [PMID: 34445383 PMCID: PMC8395518 DOI: 10.3390/ijms22168678] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Revised: 08/05/2021] [Accepted: 08/10/2021] [Indexed: 12/22/2022] Open
Abstract
As crucial signal transducers, G-proteins and G-protein-coupled receptors (GPCRs) have attracted increasing attention in the field of signal transduction. Research on G-proteins and GPCRs has mainly focused on animals, while research on plants is relatively rare. The mode of action of G-proteins is quite different from that in animals. The G-protein α (Gα) subunit is the most essential member of the G-protein signal cycle in animals and plants. The G-protein is activated when Gα releases GDP and binds to GTP, and the relationships with the GPCR and the downstream signal are also achieved by Gα coupling. It is important to study the role of Gα in the signaling pathway to explore the regulatory mechanism of G-proteins. The existence of a self-activated Gα in plants makes it unnecessary for the canonical GPCR to activate the G-protein by exchanging GDP with GTP. However, putative GPCRs have been found and proven to play important roles in G-protein signal transduction. The unique mode of action of G-proteins and the function of putative GPCRs in plants suggest that the same definition used in animal research cannot be used to study uncanonical GPCRs in plants. This review focuses on the different functions of the Gα and the mode of action between plants and animals as well as the functions of the uncanonical GPCR. This review employs a new perspective to define uncanonical GPCRs in plants and emphasizes the role of uncanonical GPCRs and Gα subunits in plant stress resistance and agricultural production.
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25
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Alhosaini K, Azhar A, Alonazi A, Al-Zoghaibi F. GPCRs: The most promiscuous druggable receptor of the mankind. Saudi Pharm J 2021; 29:539-551. [PMID: 34194261 PMCID: PMC8233523 DOI: 10.1016/j.jsps.2021.04.015] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Accepted: 04/13/2021] [Indexed: 12/11/2022] Open
Abstract
All physiological events in living organisms originated as specific chemical/biochemical signals on the cell surface and transmitted into the cytoplasm. This signal is translated within milliseconds-hours to a specific and unique order required to maintain optimum performance and homeostasis of living organisms. Examples of daily biological functions include neuronal communication and neurotransmission in the process of learning and memory, secretion (hormones, sweat, and saliva), muscle contraction, cellular growth, differentiation and migration during wound healing, and immunity to fight infections. Among the different transducers for such life-dependent signals is the large family of G protein-coupled receptors (GPCRs). GPCRs constitute roughly 800 genes, corresponding to 2% of the human genome. While GPCRs control a plethora of pathophysiological disorders, only approximately one-third of GPCR families have been deorphanized and characterized. Recent drug data show that around 40% of the recommended drugs available in the market target mainly GPCRs. In this review, we presented how such system signals, either through G protein or via other players, independent of G protein, function within the biological system. We also discussed drugs in the market or clinical trials targeting mainly GPCRs in various diseases, including cancer.
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Key Words
- AC, Adenylyl Cyclase
- Arrestin
- CCR, Chemokine Receptor
- COX, Cyclooxygenase
- DAG, Diacylglycerol
- Drugs
- ERK, Extracellular signal-Regulated Kinase
- G proteins
- GIP, Gastric Inhibitory Peptide
- GLP1R, Glucagon-Like Peptide-1 Receptor
- GPCR
- GRKs
- GRKs, G protein-coupled Receptor Kinases
- Heterodimerization
- IP3, Inositol 1,4,5-triphosphate
- MAPK, Mitogen-Activated Protein Kinase
- NMDA, N-Methyl D-Aspartate
- Nbs, Nanobodies
- PAR-1, Protease Activated Receptor 1
- PIP2, Phosphatidylinositol-4,5-bisphosphate
- PKA, Protein Kinase A
- Signaling
- cAMP, cyclic AMP
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Affiliation(s)
- Khaled Alhosaini
- Department of Pharmacology & Toxicology, College of Pharmacy, King Saud University, Post Box 2457, Riyadh 11451, Saudi Arabia
| | - Asim Azhar
- Interdisciplinary Biotechnology Unit, AMU Aligarh, UP, India
| | - Asma Alonazi
- Department of Pharmacology & Toxicology, College of Pharmacy, King Saud University, Post Box 2457, Riyadh 11451, Saudi Arabia
| | - F Al-Zoghaibi
- Molecular BioMedicine Program, Research Centre, King Faisal Specialist Hospital and Research Centre, P.O.Box: 3354, MBC:03, Riyadh 11211, Saudi Arabia
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26
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Mechanistic diversity involved in the desensitization of G protein-coupled receptors. Arch Pharm Res 2021; 44:342-353. [PMID: 33761113 DOI: 10.1007/s12272-021-01320-y] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Accepted: 03/14/2021] [Indexed: 01/14/2023]
Abstract
The desensitization of G protein-coupled receptors (GPCRs), which involves rapid loss of responsiveness due to repeated or chronic exposure to agonists, can occur through various mechanisms at different levels of signaling pathways. In this review, the mechanisms of GPCR desensitization are classified according to their occurrence at the receptor level and downstream to the receptor. The desensitization at the receptor level occurs in a phosphorylation-dependent manner, wherein the activated receptors are phosphorylated by GPCR kinases (GRKs), thereby increasing their affinities for arrestins. Arrestins bind to receptors through the cavity on the cytoplasmic region of heptahelical domains and interfere with the binding and activation of G-protein. Diverse mechanisms are involved in the desensitization that occurs downstream of the receptor. Some of these include the sequestration of G proteins, such as Gq and Gi/o by GRK2/3 and deubiquitinated arrestins, respectively. Mechanistically, GRK2/3 attenuates GPCR signaling by sequestering the Gα subunits of the Gq family and Gβγ via regulators of G protein signaling and pleckstrin homology domains, respectively. Moreover, studies on Gi/o-coupled D2-like receptors have reported that arrestins are deubiquitinated under desensitization condition and form a stable complex with Gβγ, thereby preventing them from coupling with Gα and the receptor, eventually leading to receptor signaling inhibition. Notably, the desensitization mechanism that involves arrestin deubiquitination is interesting; however, this is a new mechanism and needs to be explored further.
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27
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Stoddart LA, Kilpatrick LE, Corriden R, Kellam B, Briddon SJ, Hill SJ. Efficient G protein coupling is not required for agonist-mediated internalization and membrane reorganization of the adenosine A 3 receptor. FASEB J 2021; 35:e21211. [PMID: 33710641 PMCID: PMC9328438 DOI: 10.1096/fj.202001729rr] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Revised: 11/03/2020] [Accepted: 11/09/2020] [Indexed: 01/09/2023]
Abstract
Organization of G protein‐coupled receptors at the plasma membrane has been the focus of much recent attention. Advanced microscopy techniques have shown that these receptors can be localized to discrete microdomains and reorganization upon ligand activation is crucial in orchestrating their signaling. Here, we have compared the membrane organization and downstream signaling of a mutant (R108A, R3.50A) of the adenosine A3 receptor (A3AR) to that of the wild‐type receptor. Fluorescence Correlation Spectroscopy (FCS) studies with a fluorescent agonist (ABEA‐X‐BY630) demonstrated that both wild‐type and mutant receptors bind agonist with high affinity but in subsequent downstream signaling assays the R108A mutation abolished agonist‐mediated inhibition of cAMP production and ERK phosphorylation. In further FCS studies, both A3AR and A3AR R108A underwent similar agonist‐induced increases in receptor density and molecular brightness which were accompanied by a decrease in membrane diffusion after agonist treatment. Using bimolecular fluorescence complementation, experiments showed that the R108A mutant retained the ability to recruit β‐arrestin and these receptor/arrestin complexes displayed similar membrane diffusion and organization to that observed with wild‐type receptors. These data demonstrate that effective G protein signaling is not a prerequisite for agonist‐stimulated β‐arrestin recruitment and membrane reorganization of the A3AR.
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Affiliation(s)
- Leigh A Stoddart
- Cell Signalling and Pharmacology Research Group, Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Nottingham, UK.,Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham and University of Nottingham, Midlands, UK
| | - Laura E Kilpatrick
- Cell Signalling and Pharmacology Research Group, Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Nottingham, UK.,Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham and University of Nottingham, Midlands, UK.,School of Pharmacy, Biodiscovery Institute, University Park Nottingham, Nottingham, UK
| | - Ross Corriden
- Cell Signalling and Pharmacology Research Group, Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Nottingham, UK.,Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham and University of Nottingham, Midlands, UK
| | - Barrie Kellam
- Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham and University of Nottingham, Midlands, UK.,School of Pharmacy, Biodiscovery Institute, University Park Nottingham, Nottingham, UK
| | - Stephen J Briddon
- Cell Signalling and Pharmacology Research Group, Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Nottingham, UK.,Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham and University of Nottingham, Midlands, UK
| | - Stephen J Hill
- Cell Signalling and Pharmacology Research Group, Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Nottingham, UK.,Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham and University of Nottingham, Midlands, UK
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28
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Bock A, Bermudez M. Allosteric coupling and biased agonism in G protein‐coupled receptors. FEBS J 2021; 288:2513-2528. [DOI: 10.1111/febs.15783] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Revised: 02/05/2021] [Accepted: 02/22/2021] [Indexed: 12/11/2022]
Affiliation(s)
- Andreas Bock
- Receptor Signaling Lab Max‐Delbrueck‐Center for Molecular Medicine Berlin Germany
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29
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Onaran HO, Costa T. Conceptual and experimental issues in biased agonism. Cell Signal 2021; 82:109955. [PMID: 33607257 DOI: 10.1016/j.cellsig.2021.109955] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Revised: 01/20/2021] [Accepted: 02/14/2021] [Indexed: 12/31/2022]
Abstract
In this review, we discuss the theoretical and experimental foundations for assessing agonism in the context of signalling bias in GPCRs. We show that the formulation of efficacy in classical receptor theory and the definition of ligand-induced allosteric effect in chemical thermodynamics are coincident measures of agonism, only if we recognize that the classical model cannot be considered as a mechanistic description of the physicochemical events underlying ligand-receptor signalling. It represents instead a mathematical tool, fortuitously capable of extracting efficacy information from concentration-dependent functional data, where both ligand-dependent and ligand-independent information are present. We also assert that dissecting efficacy from affinity, as originally advocated in classical theory, is imperative for understanding the molecular property underlying agonism, and the biased agonism that leads to preferential formation of diverse GPCR-transducer complexes. Finally, we argue that beyond the assumed translational value of functional selectivity (i.e. signalling bias), the identification of ligands with true bias of efficacy is of fundamental importance for unravelling the conformational space that determines the complex functional chemistry of GPCRs.
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Affiliation(s)
- H Ongun Onaran
- Ankara University, Faculty of Medicine, Department of Pharmacology, Molecular Biology and Technology Development Unit, Ankara, Turkey.
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30
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Daley EJ, Khatri A, Dean T, Vilardaga JP, Zaidi SA, Katritch V, Gardella TJ. Ligand-Dependent Effects of Methionine-8 Oxidation in Parathyroid Hormone Peptide Analogues. Endocrinology 2021; 162:6006902. [PMID: 33242090 PMCID: PMC7774776 DOI: 10.1210/endocr/bqaa216] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Indexed: 01/29/2023]
Abstract
LA-PTH is a long-acting parathyroid hormone (PTH) peptide analogue in preclinical development for hypoparathyroidism (HP). Like native PTH, LA-PTH contains a methionine at position 8 (Met8) that is predicted to be critical for function. We assessed the impact of Met oxidation on the functional properties of LA-PTH and control PTH ligands. Oxidation of PTH(1-34) resulted in marked (~20-fold) reductions in binding affinity on the PTH receptor-1 (PTHR1) in cell membranes, similarly diminished potency for 3',5'-cyclic AMP signaling in osteoblastic cell lines (SaOS-2 and UMR106), and impaired efficacy for raising blood calcium in mice. Surprisingly, oxidation of LA-PTH resulted in little or no change in these functional responses. The signaling potency of oxidized-LA-PTH was, however, reduced approximately 40-fold compared to LA-PTH in cells expressing a PTHR1 construct that lacks the N-terminal extracellular domain (ECD). Molecular modeling revealed that while Met8 of both LA-PTH and PTH(1-34) is situated within the orthosteric ligand-binding pocket of the receptor's transmembrane domain bundle (TMD), the Met8 sidechain position is shifted for the 2 ligands so that on Met8 oxidation of PTH(1-34), steric clashes occur that are not seen with oxidized LA-PTH. The findings suggest that LA-PTH and PTH(1-34) engage the receptor differently in the Met8-interaction environment of the TMD bundle, and that this interaction environment can be allosterically influenced by the ECD component of the ligand-receptor complex. The findings should be useful for the future development of novel PTH-based peptide therapeutics for diseases of bone and mineral ion metabolism.
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Affiliation(s)
- Eileen J Daley
- Massachusetts General Hospital and Harvard Medical School, Endocrine Unit, Massachusetts General Hospital, Boston, MA, USA
| | - Ashok Khatri
- Massachusetts General Hospital and Harvard Medical School, Endocrine Unit, Massachusetts General Hospital, Boston, MA, USA
| | - Thomas Dean
- Massachusetts General Hospital and Harvard Medical School, Endocrine Unit, Massachusetts General Hospital, Boston, MA, USA
| | - Jean-Pierre Vilardaga
- University of Pittsburgh School of Medicine, Department of Pharmacology & Chemical Biology, Laboratory for GPCR Biology, Pittsburgh, PA, USA
| | - Saheem A Zaidi
- Department of Quantitative and Computational Biology, University of Southern California, Los Angeles, CA, USA
| | - Vsevolod Katritch
- Department of Quantitative and Computational Biology, University of Southern California, Los Angeles, CA, USA
| | - Thomas J Gardella
- Massachusetts General Hospital and Harvard Medical School, Endocrine Unit, Massachusetts General Hospital, Boston, MA, USA
- Correspondence: Thomas J. Gardella, PhD, Endocrine Unit, Massachusetts General Hospital, 50 Blossom St, Thier 10, Boston, MA 02474, USA.
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Hermi F, Gómez-Abellán V, Pérez-Oliva AB, García-Moreno D, López-Muñoz A, Sarropoulou E, Arizcun M, Ridha O, Mulero V, Sepulcre MP. The molecular, functional and phylogenetic characterization of PGE 2 receptors reveals their different roles in the immune response of the teleost fish gilthead seabream (Sparus aurata L.). DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2021; 114:103803. [PMID: 32738336 DOI: 10.1016/j.dci.2020.103803] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2020] [Revised: 07/14/2020] [Accepted: 07/14/2020] [Indexed: 06/11/2023]
Abstract
Prostaglandin E2 (PGE2) plays an important role in immune activities in teleost fish, including seabream. However, receptors involved in PGE2 signaling, as well as the pathways activated downstream, are largely unknown. In this study, one ortholog of mammalian PTGER1, PTGER3 and PTGER4, and two of PTGER2 (Ptger2a and Ptger2b) were identified and characterized in gilthead seabream. In silico analysis showed that all these receptors possessed the organization domain of G protein-coupled receptors, with the exception of Ptger2b. The corresponding in vivo studies revealed that they were expressed in all the tissues examined, the highest mRNA levels of ptger1 and ptger3 being observed in the spleen and of ptger2a and ptger4 in the blood. Bacterial infection induced higher mRNA levels of ptger2a, ptger3 and ptger4 in peritoneal exudate (the site of bacterial injection). In addition, head kidney acidophilic granulocytes and macrophages displayed different ptger1, ptger2a, ptger3 and ptger4 expression profiles. Furthermore, in macrophages the expression of the receptors was weakly affected by stimulation with bacterial DNA or with PGE2, while in acidophilic granulocytes stimulation resulted in the upregulation of ptger2a and ptger4. Taken together, these results suggest different roles for seabream PGE2 receptors in the regulation of the immune responses.
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Affiliation(s)
- Fatma Hermi
- Unit of Immunology, Environmental Microbiology and Cancerology, Faculty of Sciences of Bizerte, Jarzouna - Bizerte, 7021, University of Carthage, Tunis, Tunisia; Departamento de Biología Celular e Histología, Facultad de Biología, Universidad de Murcia, IMIB-Arrixaca, 30100, Murcia, Spain
| | - Victoria Gómez-Abellán
- Departamento de Biología Celular e Histología, Facultad de Biología, Universidad de Murcia, IMIB-Arrixaca, 30100, Murcia, Spain
| | - Ana B Pérez-Oliva
- Departamento de Biología Celular e Histología, Facultad de Biología, Universidad de Murcia, IMIB-Arrixaca, 30100, Murcia, Spain
| | - Diana García-Moreno
- Departamento de Biología Celular e Histología, Facultad de Biología, Universidad de Murcia, IMIB-Arrixaca, 30100, Murcia, Spain
| | - Azucena López-Muñoz
- Departamento de Biología Celular e Histología, Facultad de Biología, Universidad de Murcia, IMIB-Arrixaca, 30100, Murcia, Spain
| | - Elena Sarropoulou
- Institute for Marine Biology, Biotechnology and Aquaculture, Hellenic Centre for Marine Research, 71003, Heraklion, Crete, Greece
| | - Marta Arizcun
- Centro Oceanográfico de Murcia, Instituto Español de Oceanografía (IEO), 30860, Murcia, Spain
| | - Oueslati Ridha
- Unit of Immunology, Environmental Microbiology and Cancerology, Faculty of Sciences of Bizerte, Jarzouna - Bizerte, 7021, University of Carthage, Tunis, Tunisia
| | - Victoriano Mulero
- Departamento de Biología Celular e Histología, Facultad de Biología, Universidad de Murcia, IMIB-Arrixaca, 30100, Murcia, Spain
| | - María P Sepulcre
- Departamento de Biología Celular e Histología, Facultad de Biología, Universidad de Murcia, IMIB-Arrixaca, 30100, Murcia, Spain.
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32
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Calebiro D, Koszegi Z, Lanoiselée Y, Miljus T, O'Brien S. G protein-coupled receptor-G protein interactions: a single-molecule perspective. Physiol Rev 2020; 101:857-906. [PMID: 33331229 DOI: 10.1152/physrev.00021.2020] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
G protein-coupled receptors (GPCRs) regulate many cellular and physiological processes, responding to a diverse range of extracellular stimuli including hormones, neurotransmitters, odorants, and light. Decades of biochemical and pharmacological studies have provided fundamental insights into the mechanisms of GPCR signaling. Thanks to recent advances in structural biology, we now possess an atomistic understanding of receptor activation and G protein coupling. However, how GPCRs and G proteins interact in living cells to confer signaling efficiency and specificity remains insufficiently understood. The development of advanced optical methods, including single-molecule microscopy, has provided the means to study receptors and G proteins in living cells with unprecedented spatio-temporal resolution. The results of these studies reveal an unexpected level of complexity, whereby GPCRs undergo transient interactions among themselves as well as with G proteins and structural elements of the plasma membrane to form short-lived signaling nanodomains that likely confer both rapidity and specificity to GPCR signaling. These findings may provide new strategies to pharmaceutically modulate GPCR function, which might eventually pave the way to innovative drugs for common diseases such as diabetes or heart failure.
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Affiliation(s)
- Davide Calebiro
- Institute of Metabolism and Systems Research, University of Birmingham, Birmingham, United Kingdom; Centre of Membrane Proteins and Receptors (COMPARE), Universities of Nottingham and Birmingham, Birmingham, United Kingdom
| | - Zsombor Koszegi
- Institute of Metabolism and Systems Research, University of Birmingham, Birmingham, United Kingdom; Centre of Membrane Proteins and Receptors (COMPARE), Universities of Nottingham and Birmingham, Birmingham, United Kingdom
| | - Yann Lanoiselée
- Institute of Metabolism and Systems Research, University of Birmingham, Birmingham, United Kingdom; Centre of Membrane Proteins and Receptors (COMPARE), Universities of Nottingham and Birmingham, Birmingham, United Kingdom
| | - Tamara Miljus
- Institute of Metabolism and Systems Research, University of Birmingham, Birmingham, United Kingdom; Centre of Membrane Proteins and Receptors (COMPARE), Universities of Nottingham and Birmingham, Birmingham, United Kingdom
| | - Shannon O'Brien
- Institute of Metabolism and Systems Research, University of Birmingham, Birmingham, United Kingdom; Centre of Membrane Proteins and Receptors (COMPARE), Universities of Nottingham and Birmingham, Birmingham, United Kingdom
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van Gastel J, Leysen H, Boddaert J, Vangenechten L, Luttrell LM, Martin B, Maudsley S. Aging-related modifications to G protein-coupled receptor signaling diversity. Pharmacol Ther 2020; 223:107793. [PMID: 33316288 DOI: 10.1016/j.pharmthera.2020.107793] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Accepted: 11/26/2020] [Indexed: 02/06/2023]
Abstract
Aging is a highly complex molecular process, affecting nearly all tissue systems in humans and is the highest risk factor in developing neurodegenerative disorders such as Alzheimer's and Parkinson's disease, cardiovascular disease and Type 2 diabetes mellitus. The intense complexity of the aging process creates an incentive to develop more specific drugs that attenuate or even reverse some of the features of premature aging. As our current pharmacopeia is dominated by therapeutics that target members of the G protein-coupled receptor (GPCR) superfamily it may be prudent to search for effective anti-aging therapeutics in this fertile domain. Since the first demonstration of GPCR-based β-arrestin signaling, it has become clear that an enhanced appreciation of GPCR signaling diversity may facilitate the creation of therapeutics with selective signaling activities. Such 'biased' ligand signaling profiles can be effectively investigated using both standard molecular biological techniques as well as high-dimensionality data analyses. Through a more nuanced appreciation of the quantitative nature across the multiple dimensions of signaling bias that drugs possess, researchers may be able to further refine the efficacy of GPCR modulators to impact the complex aberrations that constitute the aging process. Identifying novel effector profiles could expand the effective pharmacopeia and assist in the design of precision medicines. This review discusses potential non-G protein effectors, and specifically their potential therapeutic suitability in aging and age-related disorders.
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Affiliation(s)
- Jaana van Gastel
- Receptor Biology Lab, Department of Biomedical Sciences, University of Antwerp, Antwerp, Belgium; Faculty of Pharmacy, Biomedical and Veterinary Science, University of Antwerp, Antwerp, Belgium
| | - Hanne Leysen
- Receptor Biology Lab, Department of Biomedical Sciences, University of Antwerp, Antwerp, Belgium; Faculty of Pharmacy, Biomedical and Veterinary Science, University of Antwerp, Antwerp, Belgium
| | - Jan Boddaert
- Molecular Pathology Group, Faculty of Medicine and Health Sciences, Laboratory of Cell Biology and Histology, Antwerp, Belgium
| | - Laura Vangenechten
- Receptor Biology Lab, Department of Biomedical Sciences, University of Antwerp, Antwerp, Belgium
| | - Louis M Luttrell
- Division of Endocrinology, Diabetes & Medical Genetics, Medical University of South Carolina, USA
| | - Bronwen Martin
- Faculty of Pharmacy, Biomedical and Veterinary Science, University of Antwerp, Antwerp, Belgium
| | - Stuart Maudsley
- Receptor Biology Lab, Department of Biomedical Sciences, University of Antwerp, Antwerp, Belgium; Faculty of Pharmacy, Biomedical and Veterinary Science, University of Antwerp, Antwerp, Belgium.
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Kenakin T. Biased signaling as allosteric probe dependence. Cell Signal 2020; 79:109844. [PMID: 33242565 DOI: 10.1016/j.cellsig.2020.109844] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2020] [Revised: 11/07/2020] [Accepted: 11/19/2020] [Indexed: 01/14/2023]
Abstract
Signaling 'bias' is a phenomenon whereby the natural allosteric probe dependence of seven transmembrane receptors allows different receptor conformations (stabilized by different agonists) to activate some signaling pathways (coupled to pleiotropically coupled receptors) more than others at the expense of those other pathways. There are a number of relevant scenarios where such an activity could be therapeutically beneficial therefore there are practical reasons why this property of receptors should be exploited. This paper discusses recent ideas around attempts to harness this potentially useful idea and also the limitations around the current methods available to do so. Specifically, the determination of a quantitative value for the receptor bias of a given agonist that may translate to useful in vivo has been particularly elusive and studies need to be directed to solving this problem.
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Affiliation(s)
- Terry Kenakin
- Department of Pharmacology, University of North Carolina School of Medicine, Chapel Hill, NC, USA.
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35
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An inactive receptor-G protein complex maintains the dynamic range of agonist-induced signaling. Proc Natl Acad Sci U S A 2020; 117:30755-30762. [PMID: 33199589 PMCID: PMC7720138 DOI: 10.1073/pnas.2010801117] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
G protein-coupled receptors (GPCRs) are targeted by a large fraction of approved drugs and regulate many important cellular processes. Conventional signaling by GPCRs is triggered when agonist-activated receptors associate with heterotrimeric G proteins. We found that serotonin 5-HT7 receptors couple to Gs proteins in an unconventional manner, in which agonist binding instead promotes dissociation of preexisting inactive 5-HT7–Gs complexes. Therefore, agonists can initiate signaling via two distinct mechanisms, by promoting the association of active receptors and G proteins and by promoting dissociation of inactive receptors and G proteins. Agonist binding promotes activation of G protein-coupled receptors (GPCRs) and association of active receptors with G protein heterotrimers. The resulting active-state ternary complex is the basis for conventional stimulus-response coupling. Although GPCRs can also associate with G proteins before agonist binding, the impact of such preassociated complexes on agonist-induced signaling is poorly understood. Here we show that preassociation of 5-HT7 serotonin receptors with Gs heterotrimers is necessary for agonist-induced signaling. 5-HT7 receptors in their inactive state associate with Gs, as these complexes are stabilized by inverse agonists and receptor mutations that favor the inactive state. Inactive-state 5-HT7–Gs complexes dissociate in response to agonists, allowing the formation of conventional agonist–5-HT7–Gs ternary complexes and subsequent Gs activation. Inactive-state 5-HT7–Gs complexes are required for the full dynamic range of agonist-induced signaling, as 5-HT7 receptors spontaneously activate Gs variants that cannot form inactive-state complexes. Therefore, agonist-induced signaling in this system involves two distinct receptor-G protein complexes, a conventional ternary complex that activates G proteins and an inverse-coupled binary complex that maintains the inactive state when agonist is not present.
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36
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Höring C, Seibel U, Tropmann K, Grätz L, Mönnich D, Pitzl S, Bernhardt G, Pockes S, Strasser A. A Dynamic, Split-Luciferase-Based Mini-G Protein Sensor to Functionally Characterize Ligands at All Four Histamine Receptor Subtypes. Int J Mol Sci 2020; 21:ijms21228440. [PMID: 33182741 PMCID: PMC7698210 DOI: 10.3390/ijms21228440] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2020] [Revised: 11/06/2020] [Accepted: 11/08/2020] [Indexed: 02/06/2023] Open
Abstract
In drug discovery, assays with proximal readout are of great importance to study target-specific effects of potential drug candidates. In the field of G protein-coupled receptors (GPCRs), the determination of GPCR-G protein interactions and G protein activation by means of radiolabeled GTP analogs ([35S]GTPγS, [γ-32P]GTP) has widely been used for this purpose. Since we were repeatedly faced with insufficient quality of radiolabeled nucleotides, there was a requirement to implement a novel proximal functional assay for the routine characterization of putative histamine receptor ligands. We applied the split-NanoLuc to the four histamine receptor subtypes (H1R, H2R, H3R, H4R) and recently engineered minimal G (mini-G) proteins. Using this method, the functional response upon receptor activation was monitored in real-time and the four mini-G sensors were evaluated by investigating selected standard (inverse) agonists and antagonists. All potencies and efficacies of the studied ligands were in concordance with literature data. Further, we demonstrated a significant positive correlation of the signal amplitude and the mini-G protein expression level in the case of the H2R, but not for the H1R or the H3R. The pEC50 values of histamine obtained under different mini-G expression levels were consistent. Moreover, we obtained excellent dynamic ranges (Z’ factor) and the signal spans were improved for all receptor subtypes in comparison to the previously performed [35S]GTPγS binding assay.
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Affiliation(s)
- Carina Höring
- Correspondence: (C.H.); , (A.S.); Tel.: +49-941-943-4748 (C.H.); +49-941-943-4821 (A.S.)
| | | | | | | | | | | | | | | | - Andrea Strasser
- Correspondence: (C.H.); , (A.S.); Tel.: +49-941-943-4748 (C.H.); +49-941-943-4821 (A.S.)
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37
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Odoemelam CS, Percival B, Wallis H, Chang MW, Ahmad Z, Scholey D, Burton E, Williams IH, Kamerlin CL, Wilson PB. G-Protein coupled receptors: structure and function in drug discovery. RSC Adv 2020; 10:36337-36348. [PMID: 35517958 PMCID: PMC9057076 DOI: 10.1039/d0ra08003a] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Accepted: 09/22/2020] [Indexed: 12/13/2022] Open
Abstract
The G-protein coupled receptors (GPCRs) superfamily comprise similar proteins arranged into families or classes thus making it one of the largest in the mammalian genome. GPCRs take part in many vital physiological functions making them targets for numerous novel drugs. GPCRs share some distinctive features, such as the seven transmembrane domains, they also differ in the number of conserved residues in their transmembrane domain. Here we provide an introductory and accessible review detailing the computational advances in GPCR pharmacology and drug discovery. An overview is provided on family A-C GPCRs; their structural differences, GPCR signalling, allosteric binding and cooperativity. The dielectric constant (relative permittivity) of proteins is also discussed in the context of site-specific environmental effects.
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Affiliation(s)
| | - Benita Percival
- Nottingham Trent University 50 Shakespeare St Nottingham NG1 4FQ UK
| | - Helen Wallis
- Nottingham Trent University 50 Shakespeare St Nottingham NG1 4FQ UK
| | - Ming-Wei Chang
- Nanotechnology and Integrated Bioengineering Centre, University of Ulster Jordanstown Campus Newtownabbey BT37 0QB Northern Ireland UK
| | - Zeeshan Ahmad
- De Montfort University The Gateway Leicester LE1 9BH UK
| | - Dawn Scholey
- Nottingham Trent University 50 Shakespeare St Nottingham NG1 4FQ UK
| | - Emily Burton
- Nottingham Trent University 50 Shakespeare St Nottingham NG1 4FQ UK
| | - Ian H Williams
- Department of Chemistry, University of Bath Claverton Down Bath BA1 7AY UK
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Torrens-Fontanals M, Stepniewski TM, Aranda-García D, Morales-Pastor A, Medel-Lacruz B, Selent J. How Do Molecular Dynamics Data Complement Static Structural Data of GPCRs. Int J Mol Sci 2020; 21:E5933. [PMID: 32824756 PMCID: PMC7460635 DOI: 10.3390/ijms21165933] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Revised: 08/11/2020] [Accepted: 08/15/2020] [Indexed: 01/08/2023] Open
Abstract
G protein-coupled receptors (GPCRs) are implicated in nearly every physiological process in the human body and therefore represent an important drug targeting class. Advances in X-ray crystallography and cryo-electron microscopy (cryo-EM) have provided multiple static structures of GPCRs in complex with various signaling partners. However, GPCR functionality is largely determined by their flexibility and ability to transition between distinct structural conformations. Due to this dynamic nature, a static snapshot does not fully explain the complexity of GPCR signal transduction. Molecular dynamics (MD) simulations offer the opportunity to simulate the structural motions of biological processes at atomic resolution. Thus, this technique can incorporate the missing information on protein flexibility into experimentally solved structures. Here, we review the contribution of MD simulations to complement static structural data and to improve our understanding of GPCR physiology and pharmacology, as well as the challenges that still need to be overcome to reach the full potential of this technique.
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Affiliation(s)
- Mariona Torrens-Fontanals
- Research Programme on Biomedical Informatics (GRIB), Hospital del Mar Medical Research Institute (IMIM)—Department of Experimental and Health Sciences, Pompeu Fabra University (UPF), 08003 Barcelona, Spain; (M.T.-F.); (T.M.S.); (D.A.-G.); (A.M.-P.); (B.M.-L.)
| | - Tomasz Maciej Stepniewski
- Research Programme on Biomedical Informatics (GRIB), Hospital del Mar Medical Research Institute (IMIM)—Department of Experimental and Health Sciences, Pompeu Fabra University (UPF), 08003 Barcelona, Spain; (M.T.-F.); (T.M.S.); (D.A.-G.); (A.M.-P.); (B.M.-L.)
- InterAx Biotech AG, PARK innovAARE, 5234 Villigen, Switzerland
- Faculty of Chemistry, Biological and Chemical Research Centre, University of Warsaw, 02-093 Warsaw, Poland
| | - David Aranda-García
- Research Programme on Biomedical Informatics (GRIB), Hospital del Mar Medical Research Institute (IMIM)—Department of Experimental and Health Sciences, Pompeu Fabra University (UPF), 08003 Barcelona, Spain; (M.T.-F.); (T.M.S.); (D.A.-G.); (A.M.-P.); (B.M.-L.)
| | - Adrián Morales-Pastor
- Research Programme on Biomedical Informatics (GRIB), Hospital del Mar Medical Research Institute (IMIM)—Department of Experimental and Health Sciences, Pompeu Fabra University (UPF), 08003 Barcelona, Spain; (M.T.-F.); (T.M.S.); (D.A.-G.); (A.M.-P.); (B.M.-L.)
| | - Brian Medel-Lacruz
- Research Programme on Biomedical Informatics (GRIB), Hospital del Mar Medical Research Institute (IMIM)—Department of Experimental and Health Sciences, Pompeu Fabra University (UPF), 08003 Barcelona, Spain; (M.T.-F.); (T.M.S.); (D.A.-G.); (A.M.-P.); (B.M.-L.)
| | - Jana Selent
- Research Programme on Biomedical Informatics (GRIB), Hospital del Mar Medical Research Institute (IMIM)—Department of Experimental and Health Sciences, Pompeu Fabra University (UPF), 08003 Barcelona, Spain; (M.T.-F.); (T.M.S.); (D.A.-G.); (A.M.-P.); (B.M.-L.)
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39
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Zhang S, Gong H, Ge Y, Ye RD. Biased allosteric modulation of formyl peptide receptor 2 leads to distinct receptor conformational states for pro- and anti-inflammatory signaling. Pharmacol Res 2020; 161:105117. [PMID: 32768626 DOI: 10.1016/j.phrs.2020.105117] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Revised: 07/25/2020] [Accepted: 07/26/2020] [Indexed: 01/26/2023]
Abstract
BACKGROUND AND PURPOSE Formyl peptide receptor 2 (FPR2) is a Class A G protein-coupled receptor (GPCR) that interacts with multiple ligands and transduces both proinflammatory and anti-inflammatory signals. These ligands include weak agonists and modulators that are produced during inflammation. The present study investigates how prolonged exposure to FPR2 modulators influence receptor signaling. EXPERIMENTAL APPROACH Fluorescent biosensors of FPR2 were constructed based on single-molecule fluorescent resonance energy transfer (FRET) and used for measurement of ligand-induced receptor conformational changes. These changes were combined with FPR2-mediated signaling events and used as parameters for the conformational states of FPR2. Ternary complex models were developed to interpret ligand concentration-dependent changes in FPR2 conformational states. KEY RESULTS Incubation with Ac2-26, an anti-inflammatory ligand of FPR2, decreased FRET intensity at picomolar concentrations. In comparison, WKYMVm (W-pep) and Aβ42, both proinflammatory agonists of FPR2, increased FRET intensity. Preincubation with Ac2-26 at 10 pM diminished W-pep-induced Ca2+ flux but potentiated W-pep-stimulated β-arrestin2 membrane translocation and p38 MAPK phosphorylation. The opposite effects were observed with 10 pM of Aβ42. Neither Ac2-26 nor Aβ42 competed for W-pep binding at the picomolar concentrations. CONCLUSIONS AND IMPLICATIONS The results support the presence of two allosteric binding sites on FPR2, each for Ac2-26 and Aβ42, with high and low affinities. Sequential binding of the two allosteric ligands at increasing concentrations induce different conformational changes in FPR2, providing a novel mechanism by which biased allosteric modulators alter receptor conformations and generate pro- and anti-inflammatory signals.
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Affiliation(s)
- Shuo Zhang
- School of Pharmacy, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Hao Gong
- School of Pharmacy, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Yunjun Ge
- State Key Laboratory for Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macau, 999078, China
| | - Richard D Ye
- School of Pharmacy, Shanghai Jiao Tong University, Shanghai, 200240, China; State Key Laboratory for Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macau, 999078, China; Kobilka Institute of Innovative Drug Discovery, School of Life and Health Sciences, The Chinese University of Hong Kong, Shenzhen, China.
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40
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Karin N. CXCR3 Ligands in Cancer and Autoimmunity, Chemoattraction of Effector T Cells, and Beyond. Front Immunol 2020; 11:976. [PMID: 32547545 PMCID: PMC7274023 DOI: 10.3389/fimmu.2020.00976] [Citation(s) in RCA: 115] [Impact Index Per Article: 28.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Accepted: 04/24/2020] [Indexed: 12/15/2022] Open
Abstract
CXCR3 is a chemokine receptor with three ligands; CXCL9, CXCL10, and CXCL11. CXCL11 binds CXCR3 with a higher affinity than the other ligands leading to receptor internalization. Long ago we reported that one of these chemokines, CXCL10, not only attracts CXCR3+ CD4+ and CD8+ effector T cells to sites of inflammation, but also direct their polarization into highly potent effector T cells. Later we showed that CXCL11 directs the linage development of T-regulatory-1 cells (Tr1). We also observed that CXCL11 and CXCL10 induce different signaling cascades via CXCR3. Collectively this suggests that CXCR3 ligands differentially regulate the biological function of T cells via biased signaling. It is generally accepted that tumor cells evolved to express several chemokine receptors and secrete their ligands. Vast majority of these chemokines support tumor growth by different mechanisms that are discussed. We suggest that CXCL10 and possibly CXCL9 differ from other chemokines by their ability to restrain tumor growth and enhance anti-tumor immunity. Along with this an accumulating number of studies showed in various human cancers a clear association between poor prognosis and low expression of CXCL10 at tumor sites, and vice versa. Finally, we discuss the possibility that CXCL9 and CXCL10 may differ in their biological function via biased signaling and its possible relevance to cancer immunotherapy. The current mini review focuses on exploring the role of CXCR3 ligands in directing the biological properties of CD4+ and CD8+ T cells in the context of cancer and autoimmunity. We believe that the combined role of these chemokines in attracting T cells and also directing their biological properties makes them key drivers of immune function.
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Affiliation(s)
- Nathan Karin
- Department of Immunology, Faculty of Medicine, Technion- Israel Institute of Technology, Haifa, Israel
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41
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Finlay DB, Duffull SB, Glass M. 100 years of modelling ligand-receptor binding and response: A focus on GPCRs. Br J Pharmacol 2020; 177:1472-1484. [PMID: 31975518 PMCID: PMC7060363 DOI: 10.1111/bph.14988] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2019] [Revised: 11/21/2019] [Accepted: 12/04/2019] [Indexed: 12/21/2022] Open
Abstract
Experimental pharmacologists rely on the application of models to describe biological observations in order to learn about a drug's effective concentration, the strength with which it binds its target and drives a response (at either molecular or system level), and the nature of more complex drug actions (allosterism/functional selectivity). Models in current use build upon decades of basic principles, going back to the beginning of the last century. Yet often, researchers are only partially familiar with these underlying principles, creating the potential for confusion due to failure to recognise the underpinning assumptions of the models that are used. Here, we describe the history of receptor theory as it underpins receptor stimulus-response models in use today, emphasising particularly attributes and models relevant to GPCRs-and point to some current aims of model development.
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Affiliation(s)
- David B. Finlay
- Department of Pharmacology and ToxicologyUniversity of OtagoDunedinNew Zealand
| | - Stephen B. Duffull
- Otago Pharmacometrics Group, School of PharmacyUniversity of OtagoDunedinNew Zealand
| | - Michelle Glass
- Department of Pharmacology and ToxicologyUniversity of OtagoDunedinNew Zealand
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42
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Biased GPCR signaling: Possible mechanisms and inherent limitations. Pharmacol Ther 2020; 211:107540. [PMID: 32201315 DOI: 10.1016/j.pharmthera.2020.107540] [Citation(s) in RCA: 60] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Accepted: 03/17/2020] [Indexed: 02/06/2023]
Abstract
G protein-coupled receptors (GPCRs) are targeted by about a third of clinically used drugs. Many GPCRs couple to more than one type of heterotrimeric G proteins, become phosphorylated by any of several different GRKs, and then bind one or more types of arrestin. Thus, classical therapeutically active drugs simultaneously initiate several branches of signaling, some of which are beneficial, whereas others result in unwanted on-target side effects. The development of novel compounds to selectively channel the signaling into the desired direction has the potential to become a breakthrough in health care. However, there are natural and technological hurdles that must be overcome. The fact that most GPCRs are subject to homologous desensitization, where the active receptor couples to G proteins, is phosphorylated by GRKs, and then binds arrestins, suggest that in most cases the GPCR conformations that facilitate their interactions with these three classes of binding partners significantly overlap. Thus, while partner-specific conformations might exist, they are likely low-probability states. GPCRs are inherently flexible, which suggests that complete bias is highly unlikely to be feasible: in the conformational ensemble induced by any ligand, there would be some conformations facilitating receptor coupling to unwanted partners. Things are further complicated by the fact that virtually every cell expresses numerous G proteins, several GRK subtypes, and two non-visual arrestins with distinct signaling capabilities. Finally, novel screening methods for measuring ligand bias must be devised, as the existing methods are not specific for one particular branch of signaling.
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Che T, English J, Krumm BE, Kim K, Pardon E, Olsen RHJ, Wang S, Zhang S, Diberto JF, Sciaky N, Carroll FI, Steyaert J, Wacker D, Roth BL. Nanobody-enabled monitoring of kappa opioid receptor states. Nat Commun 2020; 11:1145. [PMID: 32123179 PMCID: PMC7052193 DOI: 10.1038/s41467-020-14889-7] [Citation(s) in RCA: 78] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Accepted: 02/06/2020] [Indexed: 12/22/2022] Open
Abstract
Recent studies show that GPCRs rapidly interconvert between multiple states although our ability to interrogate, monitor and visualize them is limited by a relative lack of suitable tools. We previously reported two nanobodies (Nb39 and Nb6) that stabilize distinct ligand- and efficacy-delimited conformations of the kappa opioid receptor. Here, we demonstrate via X-ray crystallography a nanobody-targeted allosteric binding site by which Nb6 stabilizes a ligand-dependent inactive state. As Nb39 stabilizes an active-like state, we show how these two state-dependent nanobodies can provide real-time reporting of ligand stabilized states in cells in situ. Significantly, we demonstrate that chimeric GPCRs can be created with engineered nanobody binding sites to report ligand-stabilized states. Our results provide both insights regarding potential mechanisms for allosterically modulating KOR with nanobodies and a tool for reporting the real-time, in situ dynamic range of GPCR activity.
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MESH Headings
- Allosteric Site
- Binding Sites
- Biosensing Techniques
- Crystallography, X-Ray
- Cyclic AMP/metabolism
- Dynorphins/chemistry
- Dynorphins/pharmacology
- HEK293 Cells
- Humans
- Luminescent Measurements/methods
- Piperazines/chemistry
- Piperazines/pharmacology
- Piperidines/chemistry
- Piperidines/pharmacology
- Protein Conformation
- Pyrrolidines/chemistry
- Pyrrolidines/pharmacology
- Receptors, G-Protein-Coupled/chemistry
- Receptors, G-Protein-Coupled/metabolism
- Receptors, Opioid, kappa/agonists
- Receptors, Opioid, kappa/chemistry
- Receptors, Opioid, kappa/genetics
- Receptors, Opioid, kappa/metabolism
- Recombinant Proteins/chemistry
- Recombinant Proteins/genetics
- Recombinant Proteins/metabolism
- Single-Domain Antibodies/chemistry
- Single-Domain Antibodies/metabolism
- Tetrahydroisoquinolines/chemistry
- Tetrahydroisoquinolines/pharmacology
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Affiliation(s)
- Tao Che
- Department of Pharmacology, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC, USA.
| | - Justin English
- Department of Pharmacology, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC, USA
| | - Brian E Krumm
- Department of Pharmacology, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC, USA
| | - Kuglae Kim
- Department of Pharmacology, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC, USA
| | - Els Pardon
- Structural Biology Brussels, Vrije Universiteit Brussel (VUB), Brussels, 1050, Belgium
- VIB-VUB Center for Structural Biology, VIB, Brussels, 1050, Belgium
| | - Reid H J Olsen
- Department of Pharmacology, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC, USA
| | - Sheng Wang
- Department of Pharmacology, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC, USA
- State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, China
| | - Shicheng Zhang
- Department of Pharmacology, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC, USA
| | - Jeffrey F Diberto
- Department of Pharmacology, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC, USA
| | - Noah Sciaky
- Department of Pharmacology, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC, USA
| | - F Ivy Carroll
- Research Triangle Institute, Research Triangle Park, Durham, NC, USA
| | - Jan Steyaert
- Structural Biology Brussels, Vrije Universiteit Brussel (VUB), Brussels, 1050, Belgium
- VIB-VUB Center for Structural Biology, VIB, Brussels, 1050, Belgium
| | - Daniel Wacker
- Department of Pharmacology, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC, USA
- Department of Pharmacological Sciences and Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Bryan L Roth
- Department of Pharmacology, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC, USA.
- Division of Chemical Biology and Medicinal Chemistry, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
- National Institute of Mental Health Psychoactive Drug Screening Program (NIMH PDSP), School of Medicine, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC, USA.
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Wilkat M, Bast H, Drees R, Dünser J, Mahr A, Azoitei N, Marienfeld R, Frank F, Brhel M, Ushmorov A, Greve J, Goldberg-Bockhorn E, Theodoraki MN, Doescher J, Laban S, Schuler PJ, Hoffmann TK, Brunner C. Adenosine receptor 2B activity promotes autonomous growth, migration as well as vascularization of head and neck squamous cell carcinoma cells. Int J Cancer 2020; 147:202-217. [PMID: 31846065 DOI: 10.1002/ijc.32835] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Revised: 11/21/2019] [Accepted: 12/05/2019] [Indexed: 12/18/2022]
Abstract
Adenosine is a signaling molecule that exerts dual effects on tumor growth: while it inhibits immune cell function and thereby prevents surveillance by the immune system, it influences tumorigenesis directly via activation of adenosine receptors on tumor cells at the same time. However, the adenosine-mediated mechanisms affecting oncogenic processes particularly in head and neck squamous cell carcinomas (HNSCC) are not fully understood. Here, we investigated the role of adenosine receptor activity on HNSCC-derived cell lines. Targeting the adenosine receptor A2B (ADORA2B) on these cells with the inverse agonist/antagonist PSB-603 leads to inhibition of cell proliferation, transmigration as well as VEGFA secretion in vitro. At the molecular level, these effects were associated with cell cycle arrest as well as the induction of the apoptotic pathway. In addition, shRNA-mediated downmodulation of ADORA2B expression caused decreased proliferation. Moreover, in in vivo xenograft experiments, chemical and genetic abrogation of ADORA2B activity impaired tumor growth associated with decreased tumor vascularization. Together, our findings characterize ADORA2B as a crucial player in the maintenance of HNSCC and, therefore, as a potential therapeutic target for HNSCC treatment.
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Affiliation(s)
- Max Wilkat
- Department of Oto-Rhino-Laryngology, Head and Neck Surgery, Ulm University Medical Center, Ulm, Germany
| | - Hanna Bast
- Department of Oto-Rhino-Laryngology, Head and Neck Surgery, Ulm University Medical Center, Ulm, Germany
| | - Robert Drees
- Department of Oto-Rhino-Laryngology, Head and Neck Surgery, Ulm University Medical Center, Ulm, Germany
| | - Johannes Dünser
- Department of Oto-Rhino-Laryngology, Head and Neck Surgery, Ulm University Medical Center, Ulm, Germany
| | - Amelie Mahr
- Department of Oto-Rhino-Laryngology, Head and Neck Surgery, Ulm University Medical Center, Ulm, Germany
| | - Ninel Azoitei
- Department of Internal Medicine I, Ulm University Medical Center, Ulm, Germany
| | | | - Felicia Frank
- Department of Oto-Rhino-Laryngology, Head and Neck Surgery, Ulm University Medical Center, Ulm, Germany
| | - Magnus Brhel
- Department of Oto-Rhino-Laryngology, Head and Neck Surgery, Ulm University Medical Center, Ulm, Germany
| | - Alexey Ushmorov
- Department of Physiological Chemistry, Ulm University, Ulm, Germany
| | - Jens Greve
- Department of Oto-Rhino-Laryngology, Head and Neck Surgery, Ulm University Medical Center, Ulm, Germany
| | - Eva Goldberg-Bockhorn
- Department of Oto-Rhino-Laryngology, Head and Neck Surgery, Ulm University Medical Center, Ulm, Germany
| | - Marie-Nicole Theodoraki
- Department of Oto-Rhino-Laryngology, Head and Neck Surgery, Ulm University Medical Center, Ulm, Germany
| | - Johannes Doescher
- Department of Oto-Rhino-Laryngology, Head and Neck Surgery, Ulm University Medical Center, Ulm, Germany
| | - Simon Laban
- Department of Oto-Rhino-Laryngology, Head and Neck Surgery, Ulm University Medical Center, Ulm, Germany
| | - Patrick J Schuler
- Department of Oto-Rhino-Laryngology, Head and Neck Surgery, Ulm University Medical Center, Ulm, Germany
| | - Thomas K Hoffmann
- Department of Oto-Rhino-Laryngology, Head and Neck Surgery, Ulm University Medical Center, Ulm, Germany
| | - Cornelia Brunner
- Department of Oto-Rhino-Laryngology, Head and Neck Surgery, Ulm University Medical Center, Ulm, Germany
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45
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Gupte TM, Ritt M, Dysthe M, Malik RU, Sivaramakrishnan S. Minute-scale persistence of a GPCR conformation state triggered by non-cognate G protein interactions primes signaling. Nat Commun 2019; 10:4836. [PMID: 31645561 PMCID: PMC6811539 DOI: 10.1038/s41467-019-12755-9] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2018] [Accepted: 09/17/2019] [Indexed: 02/01/2023] Open
Abstract
Despite the crowded nature of the cellular milieu, ligand-GPCR-G protein interactions are traditionally viewed as spatially and temporally isolated events. In contrast, recent reports suggest the spatial and temporal coupling of receptor-effector interactions, with the potential to diversify downstream responses. In this study, we combine protein engineering of GPCR-G protein interactions with affinity sequestration and photo-manipulation of the crucial Gα C terminus, to demonstrate the temporal coupling of cognate and non-cognate G protein interactions through priming of the GPCR conformation. We find that interactions of the Gαs and Gαq C termini with the β2-adrenergic receptor (β2-AR), targeted at the G-protein-binding site, enhance Gs activation and cyclic AMP levels. β2-AR-Gα C termini interactions alter receptor conformation, which persists for ~90 s following Gα C terminus dissociation. Non-cognate G-protein expression levels impact cognate signaling in cells. Our study demonstrates temporal allostery in GPCRs, with implications for the modulation of downstream responses through the canonical G-protein-binding interface.
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Affiliation(s)
- Tejas M Gupte
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Twin-Cities, Minneapolis, Minnesota, 55455, USA
| | - Michael Ritt
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Twin-Cities, Minneapolis, Minnesota, 55455, USA
| | - Matthew Dysthe
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Twin-Cities, Minneapolis, Minnesota, 55455, USA
| | - Rabia U Malik
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Twin-Cities, Minneapolis, Minnesota, 55455, USA
| | - Sivaraj Sivaramakrishnan
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Twin-Cities, Minneapolis, Minnesota, 55455, USA.
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46
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Abstract
Ligand-receptor interactions, which are ubiquitous in physiology, are described by theoretical models of receptor pharmacology. Structural evidence for graded efficacy receptor conformations predicted by receptor theory has been limited but is critical to fully validate theoretical models. We applied quantitative structure-function approaches to characterize the effects of structurally similar and structurally diverse agonists on the conformational ensemble of nuclear receptor peroxisome proliferator-activated receptor γ (PPARγ). For all ligands, agonist functional efficacy is correlated to a shift in the conformational ensemble equilibrium from a ground state toward an active state, which is detected by NMR spectroscopy but not observed in crystal structures. For the structurally similar ligands, ligand potency and affinity are also correlated to efficacy and conformation, indicating ligand residence times among related analogs may influence receptor conformation and function. Our results derived from quantitative graded activity-conformation correlations provide experimental evidence and a platform with which to extend and test theoretical models of receptor pharmacology to more accurately describe and predict ligand-dependent receptor activity.
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47
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Zhao P, Furness SGB. The nature of efficacy at G protein-coupled receptors. Biochem Pharmacol 2019; 170:113647. [PMID: 31585071 DOI: 10.1016/j.bcp.2019.113647] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Accepted: 09/27/2019] [Indexed: 12/31/2022]
Abstract
G protein-coupled receptors (GPCRs) participate in many pathophysiological processes as well as almost all aspects of normal physiology. They are present at the surface of all cell types making them amenable and attractive targets for pharmaceutical therapeutics. GPCRs possess complex pharmacology with the ability to be turned on to various extents, have their constitutive activity suppressed and even switch between signaling pathways to which they couple. Underlying this complex pharmacology is GPCR signaling efficacy, and differences in efficacy promoted by alternative ligands and in different tissues is of great interest to biology in general and also the pharmaceutical industry. In this review we hope to discuss what the molecular foundations of efficacy are and whether a new approach utilizing a rate-dependent model may provide new insights into this phenomenon.
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Affiliation(s)
- Peishen Zhao
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences and Department of Pharmacology, Monash University, Parkville, Victoria 3052, Australia.
| | - Sebastian G B Furness
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences and Department of Pharmacology, Monash University, Parkville, Victoria 3052, Australia.
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48
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Santos-Otte P, Leysen H, van Gastel J, Hendrickx JO, Martin B, Maudsley S. G Protein-Coupled Receptor Systems and Their Role in Cellular Senescence. Comput Struct Biotechnol J 2019; 17:1265-1277. [PMID: 31921393 PMCID: PMC6944711 DOI: 10.1016/j.csbj.2019.08.005] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2019] [Revised: 08/20/2019] [Accepted: 08/21/2019] [Indexed: 12/17/2022] Open
Abstract
Aging is a complex biological process that is inevitable for nearly all organisms. Aging is the strongest risk factor for development of multiple neurodegenerative disorders, cancer and cardiovascular disorders. Age-related disease conditions are mainly caused by the progressive degradation of the integrity of communication systems within and between organs. This is in part mediated by, i) decreased efficiency of receptor signaling systems and ii) an increasing inability to cope with stress leading to apoptosis and cellular senescence. Cellular senescence is a natural process during embryonic development, more recently it has been shown to be also involved in the development of aging disorders and is now considered one of the major hallmarks of aging. G-protein-coupled receptors (GPCRs) comprise a superfamily of integral membrane receptors that are responsible for cell signaling events involved in nearly every physiological process. Recent advances in the molecular understanding of GPCR signaling complexity have expanded their therapeutic capacity tremendously. Emerging data now suggests the involvement of GPCRs and their associated proteins in the development of cellular senescence. With the proven efficacy of therapeutic GPCR targeting, it is reasonable to now consider GPCRs as potential platforms to control cellular senescence and the consequently, age-related disorders.
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Key Words
- ADP-ribosylation factor GTPase-activating protein, (Arf-GAP)
- AT1R blockers, (ARB)
- Aging
- Angiotensin II, (Ang II)
- Ataxia telangiectasia mutated, (ATM)
- Cellular senescence
- G protein-coupled receptor kinase interacting protein 2 (GIT2)
- G protein-coupled receptor kinase interacting protein 2, (GIT2)
- G protein-coupled receptor kinase, (GRK)
- G protein-coupled receptors (GPCRs)
- G protein-coupled receptors, (GPCRs)
- Hutchinson–Gilford progeria syndrome, (HGPS)
- Lysophosphatidic acid, (LPA)
- Regulator of G-protein signaling, (RGS)
- Relaxin family receptor 3, (RXFP3)
- active state, (R*)
- angiotensin type 1 receptor, (AT1R)
- angiotensin type 2 receptor, (AT2R)
- beta2-adrenergic receptor, (β2AR)
- cyclin-dependent kinase 2, (CDK2)
- cyclin-dependent kinase inhibitor 1, (cdkn1A/p21)
- endothelial cell differentiation gene, (Edg)
- inactive state, (R)
- latent semantic indexing, (LSI)
- mitogen-activated protein kinase, (MAPK)
- nuclear factor kappa-light-chain-enhancer of activated B cells, (NF- κβ)
- protein kinases, (PK)
- purinergic receptors family, (P2Y)
- renin-angiotensin system, (RAS)
- retinoblastoma, (RB)
- senescence associated secretory phenotype, (SASP)
- stress-induced premature senescence, (SIPS)
- transcription factor E2F3, (E2F3)
- transmembrane, (TM)
- tumor suppressor gene PTEN, (PTEN)
- tumor suppressor protein 53, (p53)
- vascular smooth muscle cells, (VSMC)
- β-Arrestin
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Affiliation(s)
- Paula Santos-Otte
- Center for Molecular and Cellular Bioengineering (CMCB), Technische Universität Dresden, 01062 Dresden, Germany
| | - Hanne Leysen
- Receptor Biology Lab, University of Antwerp, 2610 Antwerp, Belgium
- Department of Biomedical Sciences, University of Antwerp, 2610 Antwerp, Belgium
| | - Jaana van Gastel
- Receptor Biology Lab, University of Antwerp, 2610 Antwerp, Belgium
- Department of Biomedical Sciences, University of Antwerp, 2610 Antwerp, Belgium
| | - Jhana O. Hendrickx
- Receptor Biology Lab, University of Antwerp, 2610 Antwerp, Belgium
- Department of Biomedical Sciences, University of Antwerp, 2610 Antwerp, Belgium
| | - Bronwen Martin
- Receptor Biology Lab, University of Antwerp, 2610 Antwerp, Belgium
| | - Stuart Maudsley
- Receptor Biology Lab, University of Antwerp, 2610 Antwerp, Belgium
- Department of Biomedical Sciences, University of Antwerp, 2610 Antwerp, Belgium
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Molecular pharmacology of metabotropic receptors targeted by neuropsychiatric drugs. Nat Struct Mol Biol 2019; 26:535-544. [PMID: 31270468 DOI: 10.1038/s41594-019-0252-8] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2019] [Accepted: 05/15/2019] [Indexed: 12/30/2022]
Abstract
Metabotropic receptors are responsible for so-called 'slow synaptic transmission' and mediate the effects of hundreds of peptide and non-peptide neurotransmitters and neuromodulators. Over the past decade or so, a revolution in membrane-protein structural determination has clarified the molecular determinants responsible for the actions of these receptors. This Review focuses on the G protein-coupled receptors (GPCRs) that are targets of neuropsychiatric drugs and shows how insights into the structure and function of these important synaptic proteins are accelerating understanding of their actions. Notably, elucidating the structure and function of GPCRs should enhance the structure-guided discovery of novel chemical tools with which to manipulate and understand these synaptic proteins.
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Utilization of Biased G Protein-Coupled ReceptorSignaling towards Development of Safer andPersonalized Therapeutics. Molecules 2019; 24:molecules24112052. [PMID: 31146474 PMCID: PMC6600667 DOI: 10.3390/molecules24112052] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Revised: 05/19/2019] [Accepted: 05/24/2019] [Indexed: 12/12/2022] Open
Abstract
G protein-coupled receptors (GPCRs) are involved in a wide variety of physiological processes. Therefore, approximately 40% of currently prescribed drugs have targeted this receptor family. Discovery of β-arrestin mediated signaling and also separability of G protein and β-arrestin signaling pathways have switched the research focus in the GPCR field towards development of biased ligands, which provide engagement of the receptor with a certain effector, thus enriching a specific signaling pathway. In this review, we summarize possible factors that impact signaling profiles of GPCRs such as oligomerization, drug treatment, disease conditions, genetic background, etc. along with relevant molecules that can be used to modulate signaling properties of GPCRs such as allosteric or bitopic ligands, ions, aptamers and pepducins. Moreover, we also discuss the importance of inclusion of pharmacogenomics and molecular dynamics simulations to achieve a holistic understanding of the relation between genetic background and structure and function of GPCRs and GPCR-related proteins. Consequently, specific downstream signaling pathways can be enriched while those that bring unwanted side effects can be prevented on a patient-specific basis. This will improve studies that centered on development of safer and personalized therapeutics, thus alleviating the burden on economy and public health.
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