1
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Kermani AA. Applications of fluorescent protein tagging in structural studies of membrane proteins. FEBS J 2024; 291:2719-2732. [PMID: 37470714 DOI: 10.1111/febs.16910] [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: 02/23/2023] [Revised: 06/16/2023] [Accepted: 07/19/2023] [Indexed: 07/21/2023]
Abstract
Generating active, pure, and monodisperse protein remains a major bottleneck for structural studies using X-ray crystallography and cryo-electron microscopy (cryo-EM). The current methodology heavily relies on overexpressing the recombinant protein fused with a histidine tag in conventional expression systems and evaluating the quality and stability of purified protein using size exclusion chromatography (SEC). This requires a large amount of protein and can be highly laborious and time consuming. Therefore, this approach is not suitable for high-throughput screening and low-expressing macromolecules, particularly eukaryotic membrane proteins. Using fluorescent proteins fused to the target protein (applicable to both soluble and membrane proteins) enables rapid and efficient screening of expression level and monodispersity of tens of unpurified constructs using fluorescence-based size exclusion chromatography (FSEC). Moreover, FSEC proves valuable for screening multiple detergents to identify the most stabilizing agent in the case of membrane proteins. Additionally, FSEC can facilitate nanodisc reconstitution by determining the optimal ratio of membrane scaffold protein (MSP), lipids, and target protein. The distinct advantages offered by FSEC indicate that fluorescent proteins can serve as a viable alternative to commonly used affinity tags for both characterization and purification purposes. In this review, I will summarize the advantages of this technique using examples from my own work. It should be noted that this article is not intended to provide an exhaustive review of all available literature, but rather to offer representative examples of FSEC applications.
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Affiliation(s)
- Ali A Kermani
- Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, TN, USA
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2
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Kaneko S, Imai S, Uchikubo-Kamo T, Hisano T, Asao N, Shirouzu M, Shimada I. Structural and dynamic insights into the activation of the μ-opioid receptor by an allosteric modulator. Nat Commun 2024; 15:3544. [PMID: 38740791 DOI: 10.1038/s41467-024-47792-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2023] [Accepted: 04/12/2024] [Indexed: 05/16/2024] Open
Abstract
G-protein-coupled receptors (GPCRs) play pivotal roles in various physiological processes. These receptors are activated to different extents by diverse orthosteric ligands and allosteric modulators. However, the mechanisms underlying these variations in signaling activity by allosteric modulators remain largely elusive. Here, we determine the three-dimensional structure of the μ-opioid receptor (MOR), a class A GPCR, in complex with the Gi protein and an allosteric modulator, BMS-986122, using cryogenic electron microscopy. Our results reveal that BMS-986122 binding induces changes in the map densities corresponding to R1673.50 and Y2545.58, key residues in the structural motifs conserved among class A GPCRs. Nuclear magnetic resonance analyses of MOR in the absence of the Gi protein reveal that BMS-986122 binding enhances the formation of the interaction between R1673.50 and Y2545.58, thus stabilizing the fully-activated conformation, where the intracellular half of TM6 is outward-shifted to allow for interaction with the Gi protein. These findings illuminate that allosteric modulators like BMS-986122 can potentiate receptor activation through alterations in the conformational dynamics in the core region of GPCRs. Together, our results demonstrate the regulatory mechanisms of GPCRs, providing insights into the rational development of therapeutics targeting GPCRs.
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MESH Headings
- Receptors, Opioid, mu/metabolism
- Receptors, Opioid, mu/chemistry
- Receptors, Opioid, mu/genetics
- Allosteric Regulation
- Humans
- Cryoelectron Microscopy
- Protein Binding
- GTP-Binding Protein alpha Subunits, Gi-Go/metabolism
- GTP-Binding Protein alpha Subunits, Gi-Go/chemistry
- GTP-Binding Protein alpha Subunits, Gi-Go/genetics
- HEK293 Cells
- Ligands
- Models, Molecular
- Protein Conformation
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Affiliation(s)
- Shun Kaneko
- Center for Biosystems Dynamics Research (BDR), RIKEN, Kanagawa, Japan
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo, Japan
| | - Shunsuke Imai
- Center for Biosystems Dynamics Research (BDR), RIKEN, Kanagawa, Japan.
| | | | - Tamao Hisano
- Center for Biosystems Dynamics Research (BDR), RIKEN, Kanagawa, Japan
| | - Nobuaki Asao
- Center for Biosystems Dynamics Research (BDR), RIKEN, Kanagawa, Japan
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo, Japan
| | - Mikako Shirouzu
- Center for Biosystems Dynamics Research (BDR), RIKEN, Kanagawa, Japan
| | - Ichio Shimada
- Center for Biosystems Dynamics Research (BDR), RIKEN, Kanagawa, Japan.
- Graduate School of Integrated Science for Life, Hiroshima University, Hiroshima, Japan.
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3
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Claff T, Mahardhika AB, Vaaßen VJ, Schlegel J, Vielmuth C, Weiße RH, Sträter N, Müller CE. Structural Insights into Partial Activation of the Prototypic G Protein-Coupled Adenosine A 2A Receptor. ACS Pharmacol Transl Sci 2024; 7:1415-1425. [PMID: 38751633 PMCID: PMC11091970 DOI: 10.1021/acsptsci.4c00051] [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: 01/31/2024] [Revised: 02/29/2024] [Accepted: 03/01/2024] [Indexed: 05/18/2024]
Abstract
The adenosine A2A receptor (A2AAR) belongs to the rhodopsin-like G protein-coupled receptor (GPCR) family, which constitutes the largest class of GPCRs. Partial agonists show reduced efficacy as compared to physiological agonists and can even act as antagonists in the presence of a full agonist. Here, we determined an X-ray crystal structure of the partial A2AAR agonist 2-amino-6-[(1H-imidazol-2-ylmethyl)sulfanyl]-4-p-hydroxyphenyl-3,5-pyridinedicarbonitrile (LUF5834) in complex with the A2AAR construct A2A-PSB2-bRIL, stabilized in its inactive conformation and being devoid of any mutations in the ligand binding pocket. The determined high-resolution structure (2.43 Å) resolved water networks and crucial binding pocket interactions. A direct hydrogen bond of the p-hydroxy group of LUF5834 with T883.36 was observed, an amino acid that was mutated to alanine in the most frequently used A2AAR crystallization constructs thus preventing the discovery of its interactions in most of the previous A2AAR co-crystal structures. G protein dissociation studies confirmed partial agonistic activity of LUF5834 as compared to that of the full agonist N-ethylcarboxamidoadenosine (NECA). In contrast to NECA, the partial agonist was still able to bind to the receptor construct locked in its inactive conformation by an S913.39K mutation, although with an affinity lower than that at the native receptor. This could explain the compound's partial agonistic activity: while full A2AAR agonists bind exclusively to the active conformation, likely following conformational selection, partial agonists bind to active as well as inactive conformations, showing higher affinity for the active conformation. This might be a general mechanism of partial agonism also applicable to other GPCRs.
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Affiliation(s)
- Tobias Claff
- PharmaCenter
Bonn & Pharmaceutical Institute, Department of Pharmaceutical
& Medicinal Chemistry, University of
Bonn, Bonn 53113, Germany
| | - Andhika B. Mahardhika
- PharmaCenter
Bonn & Pharmaceutical Institute, Department of Pharmaceutical
& Medicinal Chemistry, University of
Bonn, Bonn 53113, Germany
- Research
Training Group 2873, University of Bonn, Bonn 53121, Germany
| | - Victoria J. Vaaßen
- PharmaCenter
Bonn & Pharmaceutical Institute, Department of Pharmaceutical
& Medicinal Chemistry, University of
Bonn, Bonn 53113, Germany
| | - Jonathan
G. Schlegel
- PharmaCenter
Bonn & Pharmaceutical Institute, Department of Pharmaceutical
& Medicinal Chemistry, University of
Bonn, Bonn 53113, Germany
| | - Christin Vielmuth
- PharmaCenter
Bonn & Pharmaceutical Institute, Department of Pharmaceutical
& Medicinal Chemistry, University of
Bonn, Bonn 53113, Germany
| | - Renato H. Weiße
- Institute
of Bioanalytical Chemistry, Center for Biotechnology and Biomedicine, Leipzig University, Leipzig 04103, Germany
| | - Norbert Sträter
- Institute
of Bioanalytical Chemistry, Center for Biotechnology and Biomedicine, Leipzig University, Leipzig 04103, Germany
| | - Christa E. Müller
- PharmaCenter
Bonn & Pharmaceutical Institute, Department of Pharmaceutical
& Medicinal Chemistry, University of
Bonn, Bonn 53113, Germany
- Research
Training Group 2873, University of Bonn, Bonn 53121, Germany
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4
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Thakur N, Ray AP, Jin B, Afsharian NP, Lyman E, Gao ZG, Jacobson KA, Eddy MT. Membrane mimetic-dependence of GPCR energy landscapes. Structure 2024; 32:523-535.e5. [PMID: 38401537 PMCID: PMC11069452 DOI: 10.1016/j.str.2024.01.013] [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: 10/16/2023] [Revised: 01/03/2024] [Accepted: 01/30/2024] [Indexed: 02/26/2024]
Abstract
We leveraged variable-temperature 19F-NMR spectroscopy to compare the conformational equilibria of the human A2A adenosine receptor (A2AAR), a class A G protein-coupled receptor (GPCR), across a range of temperatures ranging from lower temperatures typically employed in 19F-NMR experiments to physiological temperature. A2AAR complexes with partial agonists and full agonists showed large increases in the population of a fully active conformation with increasing temperature. NMR data measured at physiological temperature were more in line with functional data. This was pronounced for complexes with partial agonists, where the population of active A2AAR was nearly undetectable at lower temperature but became evident at physiological temperature. Temperature-dependent behavior of complexes with either full or partial agonists exhibited a pronounced sensitivity to the specific membrane mimetic employed. Cellular signaling experiments correlated with the temperature-dependent conformational equilibria of A2AAR in lipid nanodiscs but not in some detergents, underscoring the importance of the membrane environment in studies of GPCR function.
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Affiliation(s)
- Naveen Thakur
- Department of Chemistry, University of Florida, 126 Sisler Hall, Gainesville, FL 32611, USA
| | - Arka Prabha Ray
- Department of Chemistry, University of Florida, 126 Sisler Hall, Gainesville, FL 32611, USA
| | - Beining Jin
- Department of Chemistry, University of Florida, 126 Sisler Hall, Gainesville, FL 32611, USA
| | | | - Edward Lyman
- Department of Physics and Astronomy, University of Delaware, Newark, DE, USA
| | - Zhan-Guo Gao
- Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Kenneth A Jacobson
- Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Matthew T Eddy
- Department of Chemistry, University of Florida, 126 Sisler Hall, Gainesville, FL 32611, USA.
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5
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Imamura K, Akagi KI, Miyanoiri Y, Tsujimoto H, Hirokawa T, Ashida H, Murakami K, Inoue A, Suno R, Ikegami T, Sekiyama N, Iwata S, Kobayashi T, Tochio H. Interaction modes of human orexin 2 receptor with selective and nonselective antagonists studied by NMR spectroscopy. Structure 2024; 32:352-361.e5. [PMID: 38194963 DOI: 10.1016/j.str.2023.12.008] [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: 02/24/2023] [Revised: 08/17/2023] [Accepted: 12/13/2023] [Indexed: 01/11/2024]
Abstract
Orexin neuropeptides have many physiological roles in the sleep-wake cycle, feeding behavior, reward demands, and stress responses by activating cognitive receptors, the orexin receptors (OX1R and OX2R), distributed in the brain. There are only subtle differences between OX1R and OX2R in the orthosteric site, which has hindered the rational development of subtype-selective antagonists. In this study, we utilized solution-state NMR to capture the structural plasticity of OX2R labeled with 13CH3-ε-methionine in complex with antagonists. Mutations in the orthosteric site allosterically affected the intracellular tip of TM6. Ligand exchange experiments with the subtype-selective EMPA and the nonselective suvorexant identified three methionine residues that were substantially perturbed. The NMR spectra suggested that the suvorexant-bound state exhibited more structural plasticity than the EMPA-bound state, which has not been foreseen from the close similarity of their crystal structures, providing insights into dynamic features to be considered in understanding the ligand recognition mode.
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Affiliation(s)
- Kayo Imamura
- Department of Biophysics, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Ken-Ichi Akagi
- Section of Laboratory Equipment, National Institute of Biomedical Innovation, Health, and Nutrition, Osaka 567-0085, Japan
| | - Yohei Miyanoiri
- Institute for Protein Research, Osaka University, 3-2 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Hirokazu Tsujimoto
- Department of Cell Biology and Medical Chemistry, Graduate School of Medicine, Kyoto University, Kyoto 606-8501, Japan
| | - Takatsugu Hirokawa
- Division of Biomedical Science, Faculty of Medicine, University of Tsukuba, Tsukuba 305-8575, Japan; Transborder Medical Research Center, University of Tsukuba, Tsukuba 305-8575, Japan
| | - Hideo Ashida
- Department of Biophysics, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Kaori Murakami
- Department of Biophysics, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Asuka Inoue
- Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Miyagi 980-8578, Japan
| | - Ryoji Suno
- Department of Medical Chemistry, Kansai Medical University, Hirakata 573-1010, Japan
| | - Takahisa Ikegami
- Graduate School of Medical Life Science, Yokohama City University, 1-7-29 Suehiro, Yokohama, Kanagawa 230-0045, Japan
| | - Naotaka Sekiyama
- Department of Biophysics, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - So Iwata
- Department of Cell Biology and Medical Chemistry, Graduate School of Medicine, Kyoto University, Kyoto 606-8501, Japan
| | - Takuya Kobayashi
- Department of Medical Chemistry, Kansai Medical University, Hirakata 573-1010, Japan
| | - Hidehito Tochio
- Department of Biophysics, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan.
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6
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Jones AJY, Harman TH, Harris M, Lewis OE, Ladds G, Nietlispach D. Binding kinetics drive G protein subtype selectivity at the β 1-adrenergic receptor. Nat Commun 2024; 15:1334. [PMID: 38351103 PMCID: PMC10864275 DOI: 10.1038/s41467-024-45680-7] [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: 08/25/2023] [Accepted: 02/01/2024] [Indexed: 02/16/2024] Open
Abstract
G protein-coupled receptors (GPCRs) bind to different G protein α-subtypes with varying degrees of selectivity. The mechanism by which GPCRs achieve this selectivity is still unclear. Using 13C methyl methionine and 19F NMR, we investigate the agonist-bound active state of β1AR and its ternary complexes with different G proteins in solution. We find the receptor in the ternary complexes adopts very similar conformations. In contrast, the full agonist-bound receptor active state assumes a conformation differing from previously characterised activation intermediates or from β1AR in ternary complexes. Assessing the kinetics of binding for the agonist-bound receptor with different G proteins, we find the increased affinity of β1AR for Gs results from its much faster association with the receptor. Consequently, we suggest a kinetic-driven selectivity gate between canonical and secondary coupling which arises from differential favourability of G protein binding to the agonist-bound receptor active state.
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Affiliation(s)
- Andrew J Y Jones
- Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge, CB2 1GA, UK
| | - Thomas H Harman
- Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge, CB2 1GA, UK
| | - Matthew Harris
- Department of Pharmacology, University of Cambridge, Tennis Court Road, Cambridge, CB2 1PD, UK
| | - Oliver E Lewis
- Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge, CB2 1GA, UK
| | - Graham Ladds
- Department of Pharmacology, University of Cambridge, Tennis Court Road, Cambridge, CB2 1PD, UK
| | - Daniel Nietlispach
- Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge, CB2 1GA, UK.
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7
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Calderón JC, Ibrahim P, Gobbo D, Gervasio FL, Clark T. Activation/Deactivation Free-Energy Profiles for the β 2-Adrenergic Receptor: Ligand Modes of Action. J Chem Inf Model 2023; 63:6332-6343. [PMID: 37824365 DOI: 10.1021/acs.jcim.3c00805] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2023]
Abstract
We use enhanced-sampling simulations with an effective collective variable to study the activation of the β2-adrenergic receptor in the presence of ligands with different efficacy. The free-energy profiles are computed for the ligand-free (apo) receptor and binary (apo-receptor + G-protein α-subunit and receptor + ligand) and ternary complexes. The results are not only compatible with available experiments but also allow unprecedented structural insight into the nature of GPCR conformations along the activation pathway and their role in the activation mechanism. In particular, the simulations reveal an unexpected mode of action of partial agonists such as salmeterol and salbutamol that arises already in the binary complex without the G-protein. Specific differences in the polar interactions with residues in TM5, which are required to stabilize an optimal TM6 conformation that facilitates G-protein binding and receptor activation, play a major role in differentiating them from full agonists.
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Affiliation(s)
- Jacqueline C Calderón
- Computer-Chemistry-Center, Department of Chemistry and Pharmacy, Friedrich-Alexander-University Erlangen-Nuernberg, Naegelsbachstraße 25, 91052 Erlangen, Germany
| | - Passainte Ibrahim
- Institute of Medical Physics and Biophysics, Faculty of Medicine, University of Leipzig, 04109 Leipzig, Germany
| | - Dorothea Gobbo
- Pharmaceutical Sciences, University of Geneva, CH1206 Geneva, Switzerland
- Institute of Pharmaceutical Sciences of Western Switzerland, CH1206 Geneva, Switzerland
| | - Francesco Luigi Gervasio
- Pharmaceutical Sciences, University of Geneva, CH1206 Geneva, Switzerland
- Institute of Pharmaceutical Sciences of Western Switzerland, CH1206 Geneva, Switzerland
- Chemistry Department, University College London, WC1H 0AJ London, United Kingdom
- Swiss Bioinformatics Institute, CH1206 Geneva, Switzerland
| | - Timothy Clark
- Computer-Chemistry-Center, Department of Chemistry and Pharmacy, Friedrich-Alexander-University Erlangen-Nuernberg, Naegelsbachstraße 25, 91052 Erlangen, Germany
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8
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Thakur N, Ray AP, Lyman E, Gao ZG, Jacobson KA, Eddy MT. Membrane Mimetic-Dependence of GPCR Energy Landscapes. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.10.16.562552. [PMID: 37905159 PMCID: PMC10614885 DOI: 10.1101/2023.10.16.562552] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/02/2023]
Abstract
Protein function strongly depends on temperature, which is related to temperature-dependent changes in the equilibria of protein conformational states. We leveraged variable-temperature 19F-NMR spectroscopy to interrogate the temperature dependence of the conformational landscape of the human A2A adenosine receptor (A2AAR), a class A GPCR. Temperature-induced changes in the conformational equilibria of A2AAR in lipid nanodiscs were markedly dependent on the efficacy of bound drugs. While antagonist complexes displayed only modest changes as the temperature rose, both full and partial agonist complexes exhibited substantial increases in the active state population. Importantly, the temperature-dependent response of complexes with both full and partial agonists exhibited a pronounced sensitivity to the specific membrane mimetic employed. In striking contrast to observations within lipid nanodiscs, in detergent micelles the active state population exhibited different behavior for A2AAR complexes with both full and partial agonists. This underscores the importance of the protein environment in understanding the thermodynamics of GPCR activation.
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Affiliation(s)
- Naveen Thakur
- Department of Chemistry, University of Florida, 126 Sisler Hall, Gainesville, FL 32611, USA
| | - Arka Prabha Ray
- Department of Chemistry, University of Florida, 126 Sisler Hall, Gainesville, FL 32611, USA
| | - Edward Lyman
- Department of Physics and Astronomy, University of Delaware, Newark, Delaware, USA
| | - Zhan-Guo Gao
- Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Kenneth A Jacobson
- Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Matthew T Eddy
- Department of Chemistry, University of Florida, 126 Sisler Hall, Gainesville, FL 32611, USA
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9
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Junker H, Meiler J, Schoeder CT. Interplay of thermodynamics and evolution within the ternary ligand-GPCR-G protein complex. Curr Opin Struct Biol 2023; 82:102656. [PMID: 37467526 DOI: 10.1016/j.sbi.2023.102656] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Revised: 05/25/2023] [Accepted: 06/20/2023] [Indexed: 07/21/2023]
Abstract
Recent studies on G protein-coupled receptors (GPCRs) dynamics report that GPCRs adopt a wide range of conformations that coexist in equilibrium, with the apo state of a GPCR having a high entropy. The formation of a ligand-GPCR-transducer complex comes with a reduction of conformational space and therefore with an entropic cost. We hypothesize that the availability of binding partners, their binding affinity and the rigidity of the respective binding sites are reflected in a distinct degree of sequence conservation to balance the energetic cost of intra- and extracellular binding events. Here, we outline the current findings in delineating the conformational space and include sequential conservation of many-to-many ligand-receptor systems to discuss the entropic cost that comes with GPCR signal transduction.
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Affiliation(s)
- Hannes Junker
- Institute for Drug Discovery, University Leipzig, Faculty of Medicine, Leipzig, Germany
| | - Jens Meiler
- Institute for Drug Discovery, University Leipzig, Faculty of Medicine, Leipzig, Germany; Department of Chemistry, Vanderbilt University, Nashville, TN, United States; Center for Structural Biology, Vanderbilt University, Nashville, TN, United States
| | - Clara T Schoeder
- Institute for Drug Discovery, University Leipzig, Faculty of Medicine, Leipzig, Germany.
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10
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Jin B, Thakur N, Wijesekara AV, Eddy MT. Illuminating GPCR signaling mechanisms by NMR spectroscopy with stable-isotope labeled receptors. Curr Opin Pharmacol 2023; 72:102364. [PMID: 37612173 PMCID: PMC11221349 DOI: 10.1016/j.coph.2023.102364] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2022] [Revised: 02/06/2023] [Accepted: 02/20/2023] [Indexed: 08/25/2023]
Abstract
G protein-coupled receptors (GPCRs) exhibit remarkable structural plasticity, which underlies their capacity to recognize a wide range of extracellular molecules and interact with intracellular partner proteins. Nuclear magnetic resonance (NMR) spectroscopy is uniquely well-suited to investigate GPCR structural plasticity, enabled by stable-isotope "probes" incorporated into receptors that inform on structure and dynamics. Progress with stable-isotope labeling methods in Eukaryotic expression systems has enabled production of native or nearly-native human receptors with varied and complementary distributions of NMR probes. These advances have opened up new avenues for investigating the roles of conformational dynamics in signaling processes, including by mapping allosteric communication networks, understanding the specificity of GPCR interactions with partner proteins and exploring the impact of membrane environments on GPCR function.
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Affiliation(s)
- Beining Jin
- Department of Chemistry; University of Florida; Gainesville, FL, 32611, USA
| | - Naveen Thakur
- Department of Chemistry; University of Florida; Gainesville, FL, 32611, USA
| | | | - Matthew T Eddy
- Department of Chemistry; University of Florida; Gainesville, FL, 32611, USA.
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11
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Vuckovic Z, Wang J, Pham V, Mobbs JI, Belousoff MJ, Bhattarai A, Burger WAC, Thompson G, Yeasmin M, Nawaratne V, Leach K, van der Westhuizen ET, Khajehali E, Liang YL, Glukhova A, Wootten D, Lindsley CW, Tobin A, Sexton P, Danev R, Valant C, Miao Y, Christopoulos A, Thal DM. Pharmacological hallmarks of allostery at the M4 muscarinic receptor elucidated through structure and dynamics. eLife 2023; 12:83477. [PMID: 37248726 DOI: 10.7554/elife.83477] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2022] [Accepted: 04/12/2023] [Indexed: 05/31/2023] Open
Abstract
Allosteric modulation of G protein-coupled receptors (GPCRs) is a major paradigm in drug discovery. Despite decades of research, a molecular-level understanding of the general principles that govern the myriad pharmacological effects exerted by GPCR allosteric modulators remains limited. The M4 muscarinic acetylcholine receptor (M4 mAChR) is a validated and clinically relevant allosteric drug target for several major psychiatric and cognitive disorders. In this study, we rigorously quantified the affinity, efficacy, and magnitude of modulation of two different positive allosteric modulators, LY2033298 (LY298) and VU0467154 (VU154), combined with the endogenous agonist acetylcholine (ACh) or the high-affinity agonist iperoxo (Ipx), at the human M4 mAChR. By determining the cryo-electron microscopy structures of the M4 mAChR, bound to a cognate Gi1 protein and in complex with ACh, Ipx, LY298-Ipx, and VU154-Ipx, and applying molecular dynamics simulations, we determine key molecular mechanisms underlying allosteric pharmacology. In addition to delineating the contribution of spatially distinct binding sites on observed pharmacology, our findings also revealed a vital role for orthosteric and allosteric ligand-receptor-transducer complex stability, mediated by conformational dynamics between these sites, in the ultimate determination of affinity, efficacy, cooperativity, probe dependence, and species variability. There results provide a holistic framework for further GPCR mechanistic studies and can aid in the discovery and design of future allosteric drugs.
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Affiliation(s)
- Ziva Vuckovic
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Australia
| | - Jinan Wang
- Center for Computational Biology and Department of Molecular Biosciences, University of Kansas, Lawrence, United States
| | - Vi Pham
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Australia
| | - Jesse I Mobbs
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Australia
- ARC Centre for Cryo-electron Microscopy of Membrane Proteins, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Australia
| | - Matthew J Belousoff
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Australia
- ARC Centre for Cryo-electron Microscopy of Membrane Proteins, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Australia
| | - Apurba Bhattarai
- Center for Computational Biology and Department of Molecular Biosciences, University of Kansas, Lawrence, United States
| | - Wessel A C Burger
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Australia
- ARC Centre for Cryo-electron Microscopy of Membrane Proteins, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Australia
| | - Geoff Thompson
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Australia
| | - Mahmuda Yeasmin
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Australia
| | - Vindhya Nawaratne
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Australia
| | - Katie Leach
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Australia
- ARC Centre for Cryo-electron Microscopy of Membrane Proteins, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Australia
| | - Emma T van der Westhuizen
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Australia
| | - Elham Khajehali
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Australia
| | - Yi-Lynn Liang
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Australia
| | - Alisa Glukhova
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Australia
- ARC Centre for Cryo-electron Microscopy of Membrane Proteins, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Australia
| | - Denise Wootten
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Australia
- ARC Centre for Cryo-electron Microscopy of Membrane Proteins, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Australia
| | - Craig W Lindsley
- Department of Pharmacology, Warren Center for Neuroscience Drug Discovery and Department of Chemistry, Warren Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, United States
| | - Andrew Tobin
- The Centre for Translational Pharmacology, Advanced Research Centre (ARC), College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Patrick Sexton
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Australia
- ARC Centre for Cryo-electron Microscopy of Membrane Proteins, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Australia
| | - Radostin Danev
- Graduate School of Medicine, University of Tokyo, Tokyo, Japan
| | - Celine Valant
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Australia
| | - Yinglong Miao
- Center for Computational Biology and Department of Molecular Biosciences, University of Kansas, Lawrence, United States
| | - Arthur Christopoulos
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Australia
- ARC Centre for Cryo-electron Microscopy of Membrane Proteins, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Australia
- Neuromedicines Discovery Centre, Monash University, Parkville, Australia
| | - David M Thal
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Australia
- ARC Centre for Cryo-electron Microscopy of Membrane Proteins, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Australia
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12
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Ligands selectively tune the local and global motions of neurotensin receptor 1 (NTS 1). Cell Rep 2023; 42:112015. [PMID: 36680775 PMCID: PMC9930568 DOI: 10.1016/j.celrep.2023.112015] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Revised: 11/05/2022] [Accepted: 01/05/2023] [Indexed: 01/21/2023] Open
Abstract
Nuclear magnetic resonance (NMR) studies have revealed that fast methyl sidechain dynamics can report on entropically-driven allostery. Yet, NMR applications have been largely limited to the super-microsecond motional regimes of G protein-coupled receptors (GPCRs). We use 13Cε-methionine chemical shift-based global order parameters to test if ligands affect the fast dynamics of a thermostabilized GPCR, neurotensin receptor 1 (NTS1). We establish that the NTS1 solution ensemble includes substates with lifetimes on several, discrete timescales. The longest-lived states reflect those captured in agonist- and inverse agonist-bound crystal structures, separated by large energy barriers. We observe that the rapid fluctuations of individual methionine residues, superimposed on these long-lived states, respond collectively with the degree of fast, global dynamics correlating with ligand pharmacology. This approach lends confidence to interpreting spectra in terms of local structure and methyl dihedral angle geometry. The results suggest a role for sub-microsecond dynamics and conformational entropy in GPCR ligand discrimination.
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13
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Davies A, Tomas A. Appreciating the potential for GPCR crosstalk with ion channels. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2023; 195:101-120. [PMID: 36707150 DOI: 10.1016/bs.pmbts.2022.06.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
G protein-coupled receptors (GPCRs) are expressed by most tissues in the body and are exploited pharmacologically in a variety of pathological conditions including diabetes, cardiovascular disease, neurological diseases, and cancers. Numerous cell signaling pathways can be regulated by GPCR activation, depending on the specific GPCR, ligand and cell type. Ion channels are among the many effector proteins downstream of these signaling pathways. Saliently, ion channels are also recognized as druggable targets, and there is evidence that their activity may regulate GPCR function via membrane potential and cytoplasmic ion concentration. Overall, there appears to be a large potential for crosstalk between ion channels and GPCRs. This might have implications not only for targeting GPCRs for drug development, but also opens the possibility of co-targeting them with ion channels to achieve improved therapeutic outcomes. In this review, we highlight the large variety of possible GPCR-ion channel crosstalk modes.
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Affiliation(s)
- Amy Davies
- Section of Cell Biology and Functional Genomics, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, United Kingdom
| | - Alejandra Tomas
- Section of Cell Biology and Functional Genomics, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, United Kingdom.
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14
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Chen X, Yuan Y, Chen Y, Yu J, Wang J, Chen J, Guo Y, Pu X. Biased Activation Mechanism Induced by GPCR Heterodimerization: Observations from μOR/δOR Dimers. J Chem Inf Model 2022; 62:5581-5600. [PMID: 36377848 DOI: 10.1021/acs.jcim.2c00962] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
GPCRs regulate multiple intracellular signaling cascades. Biasedly activating one signaling pathway over the others provides additional clinical utility to optimize GPCR-based therapies. GPCR heterodimers possess different functions from their monomeric states, including their selectivity to different transducers. However, the biased signaling mechanism induced by the heterodimerization remains unclear. Motivated by the issue, we select an important GPCR heterodimer (μOR/δOR heterodimer) as a case and use microsecond Gaussian accelerated molecular dynamics simulation coupled with potential of mean force and protein structure network (PSN) to probe mechanisms regarding the heterodimerization-induced constitutive β-arrestin activity and efficacy change of the agonist DAMGO. The results show that only the lowest energy state of the μOR/δOR heterodimer, which adopts a slightly outward shift of TM6 and an ICL2 conformation close to the receptor core, can selectively accommodate β-arrestins. PSN further reveals important roles of H8, ICL1, and ICL2 in regulating the constitutive β-arrestin-biased activity for the apo μOR/δOR heterodimer. In addition, the heterodimerization can allosterically alter the binding mode of DAMGO mainly by means of W7.35. Consequently, DAMGO transmits the structural signal mainly through TM6 and TM7 in the dimer, rather than TM3 similar to the μOR monomer, thus changing the efficacy of DAMGO from a balanced agonist to the β-arrestin-biased one. On the other side, the binding of DAMGO to the heterodimer can stabilize μOR/δOR heterodimers through a stronger interaction of TM1/TM1 and H8/H8, accordingly enhancing the interaction of μOR with δOR and the binding affinity of the dimer to the β-arrestin. The agonist DAMGO does not change main compositions of the regulation network from the dimer interface to the transducer binding pocket of the μOR protomer, but induces an increase in the structural communication of the network, which should contribute to the enhanced β-arrestin coupling. Our observations, for the first time, reveal the molecular mechanism of the biased signaling induced by the heterodimerization for GPCRs, which should be beneficial to more comprehensively understand the GPCR bias signaling.
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Affiliation(s)
- Xin Chen
- College of Chemistry, Sichuan University, Chengdu610064, China
| | - Yuan Yuan
- College of Management, Southwest University for Nationalities, Chengdu610041, China
| | - Yichi Chen
- College of Chemistry, Sichuan University, Chengdu610064, China
| | - Jin Yu
- Department of Physics and Astronomy, University of California, Irvine, California92697, United States
| | - Jingzhou Wang
- College of Chemistry, Sichuan University, Chengdu610064, China
| | - Jianfang Chen
- College of Chemistry, Sichuan University, Chengdu610064, China
| | - Yanzhi Guo
- College of Chemistry, Sichuan University, Chengdu610064, China
| | - Xuemei Pu
- College of Chemistry, Sichuan University, Chengdu610064, China
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15
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Wu FJ, Rieder PS, Abiko LA, Rößler P, Gossert AD, Häussinger D, Grzesiek S. Nanobody GPS by PCS: An Efficient New NMR Analysis Method for G Protein Coupled Receptors and Other Large Proteins. J Am Chem Soc 2022; 144:21728-21740. [DOI: 10.1021/jacs.2c09692] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Affiliation(s)
- Feng-Jie Wu
- Biozentrum, University of Basel, CH-4056 Basel, Switzerland
| | - Pascal S. Rieder
- Department of Chemistry, University of Basel, CH-4056 Basel, Switzerland
| | | | - Philip Rößler
- Department of Biology, ETH Zürich, 8093 Zürich, Switzerland
| | | | - Daniel Häussinger
- Department of Chemistry, University of Basel, CH-4056 Basel, Switzerland
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16
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Olson KM, Campbell A, Alt A, Traynor JR. Finding the Perfect Fit: Conformational Biosensors to Determine the Efficacy of GPCR Ligands. ACS Pharmacol Transl Sci 2022; 5:694-709. [PMID: 36110374 PMCID: PMC9469492 DOI: 10.1021/acsptsci.1c00256] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
G protein-coupled receptors (GPCRs) are highly druggable targets that adopt numerous conformations. A ligand's ability to stabilize specific conformation(s) of its cognate receptor determines its efficacy or ability to produce a biological response. Identifying ligands that produce different receptor conformations and potentially discrete pharmacological effects (e.g., biased agonists, partial agonists, antagonists, allosteric modulators) is a major goal in drug discovery and necessary to develop drugs with better effectiveness and fewer side effects. Fortunately, direct measurements of ligand efficacy, via receptor conformational changes are possible with the recent development of conformational biosensors. In this review, we discuss classical efficacy models, including the two-state model, the ternary-complex model, and multistate models. We describe how nanobody-, transducer-, and receptor-based conformational biosensors detect and/or stabilize specific GPCR conformations to identify ligands with different levels of efficacy. In particular, conformational biosensors provide the potential to identify and/or characterize therapeutically desirable but often difficult to measure conformations of receptors faster and better than current methods. For drug discovery/development, several recent proof-of-principle studies have optimized conformational biosensors for high-throughput screening (HTS) platforms. However, their widespread use is limited by the fact that few sensors are reliably capable of detecting low-frequency conformations and technically demanding assay conditions. Nonetheless, conformational biosensors do help identify desirable ligands such as allosteric modulators, biased ligands, or partial agonists in a single assay, representing a distinct advantage over classical methods.
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Affiliation(s)
- Keith M. Olson
- Department
of Pharmacology and Edward F Domino Research Center, University of Michigan, Ann Arbor, Michigan 48109, United States
- Life
Sciences Institute, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Andra Campbell
- Department
of Pharmacology and Edward F Domino Research Center, University of Michigan, Ann Arbor, Michigan 48109, United States
- Life
Sciences Institute, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Andrew Alt
- Department
of Pharmacology and Edward F Domino Research Center, University of Michigan, Ann Arbor, Michigan 48109, United States
- Life
Sciences Institute, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - John R. Traynor
- Department
of Pharmacology and Edward F Domino Research Center, University of Michigan, Ann Arbor, Michigan 48109, United States
- Department
of Medicinal Chemistry, College of Pharmacy, University of Michigan, 428 Church Street, Ann Arbor, Michigan 48109, United
States
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17
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Ye L, Wang X, McFarland A, Madsen JJ. 19F NMR: A promising tool for dynamic conformational studies of G protein-coupled receptors. Structure 2022; 30:1372-1384. [PMID: 36130592 DOI: 10.1016/j.str.2022.08.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2021] [Revised: 07/31/2022] [Accepted: 08/23/2022] [Indexed: 10/14/2022]
Abstract
Advances in X-ray crystallography and cryoelectron microscopy enabled unprecedented insights into the activation processes of G protein-coupled receptors (GPCRs). However, these static receptor structures provide limited information about dynamics and conformational transitions that play pivotal roles in mediating signaling diversity through the multifaceted interactions between ligands, receptors, and transducers. Developing NMR approaches to probe the dynamics of conformational transitions will push the frontier of receptor science toward a more comprehensive understanding of these signaling processes. Although much progress has been made during the last decades, it remains challenging to delineate receptor conformational states and interrogate the functions of the individual states at a quantitative level. Here we cover the progress of 19F NMR applications in GPCR conformational and dynamic studies during the past 20 years. Current challenges and limitations of 19F NMR for studying GPCR dynamics are also discussed, along with experimental strategies that will drive this field forward.
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Affiliation(s)
- Libin Ye
- Department of Cell Biology, Microbiology and Molecular Biology, University of South Florida, Tampa, FL 33620, USA; H. Lee Moffitt Cancer Center & Research Institute, 12902 USF Magnolia Drive, Tampa, FL 33612, USA.
| | - Xudong Wang
- Department of Cell Biology, Microbiology and Molecular Biology, University of South Florida, Tampa, FL 33620, USA
| | - Aidan McFarland
- Department of Cell Biology, Microbiology and Molecular Biology, University of South Florida, Tampa, FL 33620, USA
| | - Jesper J Madsen
- Global and Planetary Health, College of Public Health, University of South Florida, Tampa, FL 33612, USA; Department of Molecular Medicine, Morsani College of Medicine, University of South Florida, Tampa, FL 33612, USA
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18
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Wingler LM, Feld AP. Nanobodies as Probes and Modulators of Cardiovascular G Protein-Coupled Receptors. J Cardiovasc Pharmacol 2022; 80:342-353. [PMID: 34840268 DOI: 10.1097/fjc.0000000000001185] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Accepted: 11/06/2021] [Indexed: 01/31/2023]
Abstract
ABSTRACT Understanding the activation of G protein-coupled receptors (GPCRs) is of paramount importance to the field of cardiovascular medicine due to the critical physiological roles of these receptors and their prominence as drug targets. Although many cardiovascular GPCRs have been extensively studied as model receptors for decades, new complexities in their regulation continue to emerge. As a result, there is an ongoing need to develop novel approaches to monitor and to modulate GPCR activation. In less than a decade, nanobodies, or recombinant single-domain antibody fragments from camelids, have become indispensable tools for interrogating GPCRs both in purified systems and in living cells. Nanobodies have gained traction rapidly due to their biochemical tractability and their ability to recognize defined states of native proteins. Here, we review how nanobodies have been adopted to elucidate the structure, pharmacology, and signaling of cardiovascular GPCRs, resolving long-standing mysteries and revealing unexpected mechanisms. We also discuss how advancing technologies to discover nanobodies with tailored specificities may expand the impact of these tools for both basic science and therapeutic applications.
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Affiliation(s)
- Laura M Wingler
- Department of Pharmacology and Cancer Biology, Duke University, Durham, NC
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19
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Su M, Paknejad N, Zhu L, Wang J, Do HN, Miao Y, Liu W, Hite RK, Huang XY. Structures of β 1-adrenergic receptor in complex with Gs and ligands of different efficacies. Nat Commun 2022; 13:4095. [PMID: 35835792 PMCID: PMC9283524 DOI: 10.1038/s41467-022-31823-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Accepted: 07/01/2022] [Indexed: 11/09/2022] Open
Abstract
G-protein-coupled receptors (GPCRs) receive signals from ligands with different efficacies, and transduce to heterotrimeric G-proteins to generate different degrees of physiological responses. Previous studies revealed how ligands with different efficacies activate GPCRs. Here, we investigate how a GPCR activates G-proteins upon binding ligands with different efficacies. We report the cryo-EM structures of β1-adrenergic receptor (β1-AR) in complex with Gs (GαsGβ1Gγ2) and a partial agonist or a very weak partial agonist, and compare them to the β1-AR-Gs structure in complex with a full agonist. Analyses reveal similar overall complex architecture, with local conformational differences. Cellular functional studies with mutations of β1-AR residues show effects on the cellular signaling from β1-AR to the cAMP response initiated by the three different ligands, with residue-specific functional differences. Biochemical investigations uncover that the intermediate state complex comprising β1-AR and nucleotide-free Gs is more stable when binding a full agonist than a partial agonist. Molecular dynamics simulations support the local conformational flexibilities and different stabilities among the three complexes. These data provide insights into the ligand efficacy in the activation of GPCRs and G-proteins.
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Affiliation(s)
- Minfei Su
- Department of Physiology and Biophysics, Weill Cornell Medical College of Cornell University, New York, NY, 10065, USA
| | - Navid Paknejad
- Structural Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
| | - Lan Zhu
- Cancer Center and Department of Pharmacology and Toxicology, Medical College of Wisconsin, Milwaukee, WI, 53226, USA
| | - Jinan Wang
- Center for Computational Biology and Department of Molecular Biosciences, University of Kansas, Lawrence, KS, 66047, USA
| | - Hung Nguyen Do
- Center for Computational Biology and Department of Molecular Biosciences, University of Kansas, Lawrence, KS, 66047, USA
| | - Yinglong Miao
- Center for Computational Biology and Department of Molecular Biosciences, University of Kansas, Lawrence, KS, 66047, USA
| | - Wei Liu
- Cancer Center and Department of Pharmacology and Toxicology, Medical College of Wisconsin, Milwaukee, WI, 53226, USA
| | - Richard K Hite
- Structural Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA.
| | - Xin-Yun Huang
- Department of Physiology and Biophysics, Weill Cornell Medical College of Cornell University, New York, NY, 10065, USA.
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20
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Kleist AB, Jenjak S, Sente A, Laskowski LJ, Szpakowska M, Calkins MM, Anderson EI, McNally LM, Heukers R, Bobkov V, Peterson FC, Thomas MA, Chevigné A, Smit MJ, McCorvy JD, Babu MM, Volkman BF. Conformational selection guides β-arrestin recruitment at a biased G protein-coupled receptor. Science 2022; 377:222-228. [PMID: 35857540 PMCID: PMC9574477 DOI: 10.1126/science.abj4922] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
G protein-coupled receptors (GPCRs) recruit β-arrestins to coordinate diverse cellular processes, but the structural dynamics driving this process are poorly understood. Atypical chemokine receptors (ACKRs) are intrinsically biased GPCRs that engage β-arrestins but not G proteins, making them a model system for investigating the structural basis of β-arrestin recruitment. Here, we performed nuclear magnetic resonance (NMR) experiments on 13CH3-ε-methionine-labeled ACKR3, revealing that β-arrestin recruitment is associated with conformational exchange at key regions of the extracellular ligand-binding pocket and intracellular β-arrestin-coupling region. NMR studies of ACKR3 mutants defective in β-arrestin recruitment identified an allosteric hub in the receptor core that coordinates transitions among heterogeneously populated and selected conformational states. Our data suggest that conformational selection guides β-arrestin recruitment by tuning receptor dynamics at intracellular and extracellular regions.
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Affiliation(s)
- Andrew B Kleist
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, WI 53226, USA.,Medical Scientist Training Program, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Shawn Jenjak
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Andrija Sente
- MRC Laboratory of Molecular Biology, Cambridge CB2 0QH, UK
| | - Lauren J Laskowski
- Department of Cell Biology, Neurobiology, and Anatomy, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Martyna Szpakowska
- Immuno-Pharmacology and Interactomics, Department of Infection and Immunity, Luxembourg Institute of Health (LIH), L-4354 Esch-sur-Alzette, Luxembourg
| | - Maggie M Calkins
- Department of Cell Biology, Neurobiology, and Anatomy, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Emilie I Anderson
- Department of Cell Biology, Neurobiology, and Anatomy, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Lisa M McNally
- Department of Cell Biology, Neurobiology, and Anatomy, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Raimond Heukers
- Amsterdam Institute for Molecular and Life Sciences, Division of Medicinal Chemistry, Faculty of Sciences, Vrije Universiteit, 1081 HZ Amsterdam, Netherlands
| | - Vladimir Bobkov
- Amsterdam Institute for Molecular and Life Sciences, Division of Medicinal Chemistry, Faculty of Sciences, Vrije Universiteit, 1081 HZ Amsterdam, Netherlands
| | - Francis C Peterson
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Monica A Thomas
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, WI 53226, USA.,Medical Scientist Training Program, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Andy Chevigné
- Immuno-Pharmacology and Interactomics, Department of Infection and Immunity, Luxembourg Institute of Health (LIH), L-4354 Esch-sur-Alzette, Luxembourg
| | - Martine J Smit
- Amsterdam Institute for Molecular and Life Sciences, Division of Medicinal Chemistry, Faculty of Sciences, Vrije Universiteit, 1081 HZ Amsterdam, Netherlands
| | - John D McCorvy
- Department of Cell Biology, Neurobiology, and Anatomy, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - M Madan Babu
- Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA.,Center for Data Driven Discovery, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Brian F Volkman
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, WI 53226, USA
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21
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G Protein-coupled Receptor (GPCR) Reconstitution and Labeling for Solution Nuclear Magnetic Resonance (NMR) Studies of the Structural Basis of Transmembrane Signaling. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27092658. [PMID: 35566006 PMCID: PMC9101874 DOI: 10.3390/molecules27092658] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Revised: 04/14/2022] [Accepted: 04/14/2022] [Indexed: 11/17/2022]
Abstract
G protein-coupled receptors (GPCRs) are a large membrane protein family found in higher organisms, including the human body. GPCRs mediate cellular responses to diverse extracellular stimuli and thus control key physiological functions, which makes them important targets for drug design. Signaling by GPCRs is related to the structure and dynamics of these proteins, which are modulated by extrinsic ligands as well as by intracellular binding partners such as G proteins and arrestins. Here, we review some basics of using nuclear magnetic resonance (NMR) spectroscopy in solution for the characterization of GPCR conformations and intermolecular interactions that relate to transmembrane signaling.
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22
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GPCR large-amplitude dynamics by 19F-NMR of aprepitant bound to the neurokinin 1 receptor. Proc Natl Acad Sci U S A 2022; 119:e2122682119. [PMID: 35377814 PMCID: PMC9169749 DOI: 10.1073/pnas.2122682119] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Comparisons of G protein-coupled receptor (GPCR) complexes with agonists and antagonists based on X-ray crystallography and cryo-electron microscopy structure determinations show differences in the width of the orthosteric ligand binding groove over the range from 0.3 to 2.9 Å. Here, we show that there are transient structure fluctuations with amplitudes up to at least 6 Å. The experiments were performed with the neurokinin 1 receptor (NK1R), a GPCR of class A that is involved in inflammation, pain, and cancer. We used 19F-NMR observation of aprepitant, which is an approved drug that targets NK1R for the treatment of chemotherapy-induced nausea and vomiting. Aprepitant includes a bis-trifluoromethyl-phenyl ring attached with a single bond to the core of the molecule; 19F-NMR revealed 180° flipping motions of this ring about this bond. In the picture emerging from the 19F-NMR data, the GPCR transmembrane helices undergo large-scale floating motions in the lipid bilayer. The functional implication is of extensive promiscuity of initial ligand binding, primarily determined by size and shape of the ligand, with subsequent selection by unique interactions between atom groups of the ligand and the GPCR within the binding groove. This second step ensures the wide range of different efficacies documented for GPCR-targeting drugs. The NK1R data also provide a rationale for the observation that diffracting GPCR crystals are obtained for complexes with only very few of the ligands from libraries of approved drugs and lead compounds that bind to the receptors.
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23
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Huang SK, Prosser RS. Dynamics and Mechanistic Underpinnings to Pharmacology of Class A GPCRs - An NMR Perspective. Am J Physiol Cell Physiol 2022; 322:C739-C753. [PMID: 35235425 DOI: 10.1152/ajpcell.00044.2022] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
One-third of current pharmaceuticals target G protein-coupled receptors (GPCRs), the largest receptor superfamily in humans and mediators of diverse physiological processes. This review summarizes the recent progress in GPCR structural dynamics, focusing on class A receptors and insights derived from nuclear magnetic resonance (NMR) and other spectroscopic techniques. We describe the structural aspects of GPCR activation and the various pharmacological models that capture aspects of receptor signaling behaviour. Spectroscopic studies revealed that receptors and their signaling complexes are dynamic allosteric systems that sample multiple functional states under basal conditions. The distribution of states within the conformational ensemble and the kinetics of transitions between states are regulated through the binding of ligands, allosteric modulators, and the membrane environment. This ensemble view of GPCRs provides a mechanistic framework for understanding many of the pharmacological phenomena associated with receptor signaling, such as basal activity, efficacy, and functional bias.
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Affiliation(s)
- Shuya Kate Huang
- Department of Chemistry, University of Toronto, Toronto, Ontario, Canada.,Department of Chemical and Physical Sciences, University of Toronto Mississauga, Mississauga, Ontario, Canada
| | - R Scott Prosser
- Department of Chemistry, University of Toronto, Toronto, Ontario, Canada.,Department of Chemical and Physical Sciences, University of Toronto Mississauga, Mississauga, Ontario, Canada.,Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada
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24
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Chandler B, Todd L, Smith SO. Magic angle spinning NMR of G protein-coupled receptors. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2022; 128:25-43. [PMID: 35282868 PMCID: PMC10718405 DOI: 10.1016/j.pnmrs.2021.10.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Revised: 10/26/2021] [Accepted: 10/27/2021] [Indexed: 06/14/2023]
Abstract
G protein-coupled receptors (GPCRs) have a simple seven transmembrane helix architecture which has evolved to recognize a diverse number of chemical signals. The more than 800 GPCRs encoded in the human genome function as receptors for vision, smell and taste, and mediate key physiological processes. Consequently, these receptors are a major target for pharmaceuticals. Protein crystallography and electron cryo-microscopy have provided high resolution structures of many GPCRs in both active and inactive conformations. However, these structures have not sparked a surge in rational drug design, in part because GPCRs are inherently dynamic and the structural changes induced by ligand or drug binding to stabilize inactive or active conformations are often subtle rearrangements in packing or hydrogen-bonding interactions. NMR spectroscopy provides a sensitive probe of local structure and dynamics at specific sites within these receptors as well as global changes in receptor structure and dynamics. These methods can also capture intermediate states and conformations with low populations that provide insights into the activation pathways. We review the use of solid-state magic angle spinning NMR to address the structure and activation mechanisms of GPCRs. The focus is on the large and diverse class A family of receptors. We highlight three specific class A GPCRs in order to illustrate how solid-state, as well as solution-state, NMR spectroscopy can answer questions in the field involving how different GPCR classes and subfamilies are activated by their associated ligands, and how small molecule drugs can modulate GPCR activation.
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Affiliation(s)
- Bianca Chandler
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY 11794, United States.
| | - Lauren Todd
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY 11794, United States.
| | - Steven O Smith
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY 11794, United States.
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Synthesis, biological, and structural explorations of a series of μ-opioid receptor (MOR) agonists with high G protein signaling bias. Eur J Med Chem 2022; 228:113986. [PMID: 34802839 DOI: 10.1016/j.ejmech.2021.113986] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Revised: 11/04/2021] [Accepted: 11/08/2021] [Indexed: 11/20/2022]
Abstract
Biased agonism refers to the ability of compounds to drive preferred signaling pathways and avoid adverse signaling pathways in a ligand-dependent manner for some G-protein-coupled receptors. It is thought that the separation of therapeutic efficacy (e.g., analgesia) from adverse effects (e.g., respiration depression) can be achieved through the design of biased MOR agonists and one example is the recently approved MOR biased agonist oliceridine (TRV130). However, oliceridine only demonstrates modest beneficial effects as compared to other opioids in terms of therapeutic/adverse effect balance. One possibility attributable to the modest success of oliceridine is its limited bias, and as such developing MOR ligands with a more biased agonism profile could in theory further improve the beneficial effects of the ligands. Here, we rationally designed and synthesized a series of derivatives as potent highly biased MOR agonists (19a-v) through the modification and structure-activity relationship study of TRV130. This novel synthetic molecule, LPM3480392 (19m), demonstrated improved in vitro biased agonism (EC50 = 0.35 nM, Emax = 91.4%) with no measured β-arrestin recruitment (EC50 > 30000 nM, Emax = 1.6%), good brain penetration (B/P ratio = 4.61, 0.25 h post-IV dosing 2.0 mg/kg), a favorable pharmacokinetic profile (distribution volume = 10766 mL/kg, t1/2 = 1.9 h) and produced potent antinociceptive effect with reduced respiratory suppression (sO2(%) = 92.17, 0.32 mg/kg, SC) as compared to TRV130. LPM3480392 has completed preclinical studies and is currently under clinical development (CTR20210370) as an analgesic for the treatment of moderate to severe pain.
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Abstract
Cryogenic electron microscopy (cryo-EM) has revolutionized the field of structural biology, particularly in solving the structures of large protein complexes or cellular machineries that play important biological functions. This review focuses on the contribution and future potential of cryo-EM in related emerging applications-enzymatic mechanisms and dynamic processes. Work on these subjects can benefit greatly from the capability of cryo-EM to solve the structures of specific protein complexes in multiple conditions, including variations in the buffer condition, ligands, and temperature, and to capture multiple conformational states, conformational change intermediates, and reaction intermediates. These studies can expand the structural landscape of specific proteins or protein complexes in multiple dimensions and drive new advances in the fields of enzymology and dynamic processes. The advantages and complementarity of cryo-EM relative to X-ray crystallography and nuclear magnetic resonance with regard to these applications are also addressed. Expected final online publication date for the Annual Review of Biophysics, Volume 51 is May 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
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Affiliation(s)
- Ming-Daw Tsai
- Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan; .,Institute of Biochemical Sciences, National Taiwan University, Taipei, Taiwan
| | - Wen-Jin Wu
- Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan;
| | - Meng-Chiao Ho
- Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan; .,Institute of Biochemical Sciences, National Taiwan University, Taipei, Taiwan
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27
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Jespers W, Heitman LH, IJzerman AP, Sotelo E, van Westen GJP, Åqvist J, Gutiérrez-de-Terán H. Deciphering conformational selectivity in the A2A adenosine G protein-coupled receptor by free energy simulations. PLoS Comput Biol 2021; 17:e1009152. [PMID: 34818333 PMCID: PMC8654218 DOI: 10.1371/journal.pcbi.1009152] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2021] [Revised: 12/08/2021] [Accepted: 11/11/2021] [Indexed: 12/25/2022] Open
Abstract
Transmembranal G Protein-Coupled Receptors (GPCRs) transduce extracellular chemical signals to the cell, via conformational change from a resting (inactive) to an active (canonically bound to a G-protein) conformation. Receptor activation is normally modulated by extracellular ligand binding, but mutations in the receptor can also shift this equilibrium by stabilizing different conformational states. In this work, we built structure-energetic relationships of receptor activation based on original thermodynamic cycles that represent the conformational equilibrium of the prototypical A2A adenosine receptor (AR). These cycles were solved with efficient free energy perturbation (FEP) protocols, allowing to distinguish the pharmacological profile of different series of A2AAR agonists with different efficacies. The modulatory effects of point mutations on the basal activity of the receptor or on ligand efficacies could also be detected. This methodology can guide GPCR ligand design with tailored pharmacological properties, or allow the identification of mutations that modulate receptor activation with potential clinical implications. The design of new ligands as chemical modulators of G protein-coupled receptors (GPCRs) has benefited considerably during the last years of advances in both the structural and computational biology disciplines. Within the last area, the use of free energy calculation methods has arisen as a computational tool to predict ligand affinities to explain structure-affinity relationships and guide lead optimization campaigns. However, our comprehension of the structural determinants of ligands with different pharmacological profile is scarce, and knowledge of the chemical modifications associated with an agonistic or antagonistic profile would be extremely valuable. We herein report an original implementation of the thermodynamic cycles associated with free energy perturbation (FEP) simulations, to mimic the conformational equilibrium between active and inactive GPCRs, and establish a framework to describe pharmacological profiles as a function of the ligands selectivity for a given receptor conformation. The advantage of this method resides into its simplicity of use, and the only consideration of active and inactive conformations of the receptor, with no simulation of the transitions between them. This model can accurately predict the pharmacological profile of series of full and partial agonists as opposed to antagonists of the A2A adenosine receptor, and moreover, how certain mutations associated with modulation of basal activity can influence this pharmacological profiles, which enables our understanding of such clinically relevant mutations.
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Affiliation(s)
- Willem Jespers
- Department of Cell and Molecular Biology, Uppsala University, Biomedical Center (BMC), Uppsala, Sweden
- Drug Discovery and Safety, Leiden Academic Centre for Drug Research, Leiden, The Netherlands
- * E-mail: (WJ); (HGT)
| | - Laura H. Heitman
- Drug Discovery and Safety, Leiden Academic Centre for Drug Research, Leiden, The Netherlands
- Oncode Institute, Leiden, Leiden
| | - Adriaan P. IJzerman
- Drug Discovery and Safety, Leiden Academic Centre for Drug Research, Leiden, The Netherlands
| | - Eddy Sotelo
- Centro Singular de Investigación en Química Biolóxica y Materiais Moleculares (CIQUS), Santiago de Compostela, Spain
- Departamento de Química Orgánica, Facultade de Farmacia, Universidade de Santiago de Compostela, Santiago de Compostela, Spain
| | - Gerard J. P. van Westen
- Drug Discovery and Safety, Leiden Academic Centre for Drug Research, Leiden, The Netherlands
| | - Johan Åqvist
- Department of Cell and Molecular Biology, Uppsala University, Biomedical Center (BMC), Uppsala, Sweden
| | - Hugo Gutiérrez-de-Terán
- Department of Cell and Molecular Biology, Uppsala University, Biomedical Center (BMC), Uppsala, Sweden
- Science for Life Laboratories, BMC, Uppsala, Sweden
- * E-mail: (WJ); (HGT)
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Katayama K, Suzuki K, Suno R, Kise R, Tsujimoto H, Iwata S, Inoue A, Kobayashi T, Kandori H. Vibrational spectroscopy analysis of ligand efficacy in human M 2 muscarinic acetylcholine receptor (M 2R). Commun Biol 2021; 4:1321. [PMID: 34815515 PMCID: PMC8635417 DOI: 10.1038/s42003-021-02836-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2021] [Accepted: 11/01/2021] [Indexed: 12/30/2022] Open
Abstract
The intrinsic efficacy of ligand binding to G protein-coupled receptors (GPCRs) reflects the ability of the ligand to differentially activate its receptor to cause a physiological effect. Here we use attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectroscopy to examine the ligand-dependent conformational changes in the human M2 muscarinic acetylcholine receptor (M2R). We show that different ligands affect conformational alteration appearing at the C=O stretch of amide-I band in M2R. Notably, ATR-FTIR signals strongly correlated with G-protein activation levels in cells. Together, we propose that amide-I band serves as an infrared probe to distinguish the ligand efficacy in M2R and paves the path to rationally design ligands with varied efficacy towards the target GPCR.
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Affiliation(s)
- Kota Katayama
- Department of Life Science and Applied Chemistry, Nagoya Institute of Technology, Showa-ku, Nagoya, 466-8555, Japan.
- OptoBioTechnology Research Center, Nagoya Institute of Technology, Showa-ku, Nagoya, 466-8555, Japan.
- PRESTO, Japan Science and Technology Agency, 4-1-8 Honcho, Kawaguchi, Saitama, 332-0012, Japan.
| | - Kohei Suzuki
- Department of Life Science and Applied Chemistry, Nagoya Institute of Technology, Showa-ku, Nagoya, 466-8555, Japan
| | - Ryoji Suno
- Department of Medical Chemistry, Kansai Medical University, Hirakata, 573-1010, Japan
| | - Ryoji Kise
- Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Miyagi, 980-8578, Japan
| | - Hirokazu Tsujimoto
- Department of Cell Biology and Medical Chemistry, Graduate School of Medicine, Kyoto University, Kyoto, 606-8501, Japan
| | - So Iwata
- Department of Cell Biology and Medical Chemistry, Graduate School of Medicine, Kyoto University, Kyoto, 606-8501, Japan
| | - Asuka Inoue
- Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Miyagi, 980-8578, Japan
| | - Takuya Kobayashi
- Department of Medical Chemistry, Kansai Medical University, Hirakata, 573-1010, Japan
- Japan Agency for Medical Research and Development, Core Research for Evolutional Science and Technology (AMED-CREST), Chiyoda-ku, Tokyo, 100-0004, Japan
| | - Hideki Kandori
- Department of Life Science and Applied Chemistry, Nagoya Institute of Technology, Showa-ku, Nagoya, 466-8555, Japan.
- OptoBioTechnology Research Center, Nagoya Institute of Technology, Showa-ku, Nagoya, 466-8555, Japan.
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29
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Cong X, Maurel D, Déméné H, Vasiliauskaité-Brooks I, Hagelberger J, Peysson F, Saint-Paul J, Golebiowski J, Granier S, Sounier R. Molecular insights into the biased signaling mechanism of the μ-opioid receptor. Mol Cell 2021; 81:4165-4175.e6. [PMID: 34433090 DOI: 10.1016/j.molcel.2021.07.033] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Revised: 06/18/2021] [Accepted: 07/27/2021] [Indexed: 02/08/2023]
Abstract
GPCR functional selectivity opens new opportunities for the design of safer drugs. Ligands orchestrate GPCR signaling cascades by modulating the receptor conformational landscape. Our study provides insights into the dynamic mechanism enabling opioid ligands to preferentially activate the G protein over the β-arrestin pathways through the μ-opioid receptor (μOR). We combine functional assays in living cells, solution NMR spectroscopy, and enhanced-sampling molecular dynamic simulations to identify the specific μOR conformations induced by G protein-biased agonists. In particular, we describe the dynamic and allosteric communications between the ligand-binding pocket and the receptor intracellular domains, through conserved motifs in class A GPCRs. Most strikingly, the biased agonists trigger μOR conformational changes in the intracellular loop 1 and helix 8 domains, which may impair β-arrestin binding or signaling. The findings may apply to other GPCR families and provide key molecular information that could facilitate the design of biased ligands.
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Affiliation(s)
- Xiaojing Cong
- Institut de Génomique Fonctionnelle, CNRS UMR-5203 INSERM U1191, University of Montpellier, 34000 Montpellier, France
| | - Damien Maurel
- Institut de Génomique Fonctionnelle, CNRS UMR-5203 INSERM U1191, University of Montpellier, 34000 Montpellier, France
| | - Hélène Déméné
- Centre de Biochimie Structurale, CNRS UMR 5048-INSERM 1054, University of Montpellier, 29 rue de Navacelles, 34090 Montpellier Cedex, France
| | - Ieva Vasiliauskaité-Brooks
- Institut de Génomique Fonctionnelle, CNRS UMR-5203 INSERM U1191, University of Montpellier, 34000 Montpellier, France
| | - Joanna Hagelberger
- Institut de Génomique Fonctionnelle, CNRS UMR-5203 INSERM U1191, University of Montpellier, 34000 Montpellier, France
| | - Fanny Peysson
- Institut de Génomique Fonctionnelle, CNRS UMR-5203 INSERM U1191, University of Montpellier, 34000 Montpellier, France
| | - Julie Saint-Paul
- Institut de Génomique Fonctionnelle, CNRS UMR-5203 INSERM U1191, University of Montpellier, 34000 Montpellier, France
| | - Jérôme Golebiowski
- Université Côte d'Azur, CNRS, Institute of Chemistry of Nice UMR7272, 06108 Nice, France; Department of Brain and Cognitive Sciences, Daegu Gyeongbuk Institute of Science and Technology, Daegu 711-873, South Korea
| | - Sébastien Granier
- Institut de Génomique Fonctionnelle, CNRS UMR-5203 INSERM U1191, University of Montpellier, 34000 Montpellier, France.
| | - Rémy Sounier
- Institut de Génomique Fonctionnelle, CNRS UMR-5203 INSERM U1191, University of Montpellier, 34000 Montpellier, France.
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30
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Function-Related Dynamics in Multi-Spanning Helical Membrane Proteins Revealed by Solution NMR. MEMBRANES 2021; 11:membranes11080604. [PMID: 34436367 PMCID: PMC8398610 DOI: 10.3390/membranes11080604] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Revised: 08/03/2021] [Accepted: 08/05/2021] [Indexed: 01/02/2023]
Abstract
A primary biological function of multi-spanning membrane proteins is to transfer information and/or materials through a membrane by changing their conformations. Therefore, particular dynamics of the membrane proteins are tightly associated with their function. The semi-atomic resolution dynamics information revealed by NMR is able to discriminate function-related dynamics from random fluctuations. This review will discuss several studies in which quantitative dynamics information by solution NMR has contributed to revealing the structural basis of the function of multi-spanning membrane proteins, such as ion channels, GPCRs, and transporters.
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31
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Hilger D. The role of structural dynamics in GPCR‐mediated signaling. FEBS J 2021; 288:2461-2489. [DOI: 10.1111/febs.15841] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Revised: 03/19/2021] [Accepted: 03/24/2021] [Indexed: 12/18/2022]
Affiliation(s)
- Daniel Hilger
- Department of Pharmaceutical Chemistry Philipps‐University Marburg Germany
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32
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Huang SK, Pandey A, Tran DP, Villanueva NL, Kitao A, Sunahara RK, Sljoka A, Prosser RS. Delineating the conformational landscape of the adenosine A 2A receptor during G protein coupling. Cell 2021; 184:1884-1894.e14. [PMID: 33743210 DOI: 10.1016/j.cell.2021.02.041] [Citation(s) in RCA: 81] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Revised: 12/02/2020] [Accepted: 02/17/2021] [Indexed: 12/17/2022]
Abstract
G-protein-coupled receptors (GPCRs) represent a ubiquitous membrane protein family and are important drug targets. Their diverse signaling pathways are driven by complex pharmacology arising from a conformational ensemble rarely captured by structural methods. Here, fluorine nuclear magnetic resonance spectroscopy (19F NMR) is used to delineate key functional states of the adenosine A2A receptor (A2AR) complexed with heterotrimeric G protein (Gαsβ1γ2) in a phospholipid membrane milieu. Analysis of A2AR spectra as a function of ligand, G protein, and nucleotide identifies an ensemble represented by inactive states, a G-protein-bound activation intermediate, and distinct nucleotide-free states associated with either partial- or full-agonist-driven activation. The Gβγ subunit is found to be critical in facilitating ligand-dependent allosteric transmission, as shown by 19F NMR, biochemical, and computational studies. The results provide a mechanistic basis for understanding basal signaling, efficacy, precoupling, and allostery in GPCRs.
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Affiliation(s)
- Shuya Kate Huang
- Department of Chemistry, University of Toronto, UTM, 3359 Mississauga Road North, Mississauga, Ontario L5L 1C6, Canada
| | - Aditya Pandey
- Department of Chemistry, University of Toronto, UTM, 3359 Mississauga Road North, Mississauga, Ontario L5L 1C6, Canada; Department of Biochemistry, University of Toronto, 1 King's College Circle, Toronto, Ontario M5S 1A8, Canada
| | - Duy Phuoc Tran
- School of Life Science and Technology, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo 152-8550, Japan
| | - Nicolas L Villanueva
- Department of Pharmacology, University of California San Diego School of Medicine, 9500 Gilman Drive, La Jolla, CA 92093, USA
| | - Akio Kitao
- School of Life Science and Technology, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo 152-8550, Japan
| | - Roger K Sunahara
- Department of Pharmacology, University of California San Diego School of Medicine, 9500 Gilman Drive, La Jolla, CA 92093, USA
| | - Adnan Sljoka
- Department of Chemistry, University of Toronto, UTM, 3359 Mississauga Road North, Mississauga, Ontario L5L 1C6, Canada; RIKEN Center for Advanced Intelligence Project, RIKEN, 1-4-1 Nihombashi, Chuo-ku, Tokyo 103-0027, Japan.
| | - R Scott Prosser
- Department of Chemistry, University of Toronto, UTM, 3359 Mississauga Road North, Mississauga, Ontario L5L 1C6, Canada; Department of Biochemistry, University of Toronto, 1 King's College Circle, Toronto, Ontario M5S 1A8, Canada.
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33
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Waltenspühl Y, Ehrenmann J, Klenk C, Plückthun A. Engineering of Challenging G Protein-Coupled Receptors for Structure Determination and Biophysical Studies. Molecules 2021; 26:molecules26051465. [PMID: 33800379 PMCID: PMC7962830 DOI: 10.3390/molecules26051465] [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: 01/15/2021] [Revised: 02/27/2021] [Accepted: 03/01/2021] [Indexed: 01/14/2023] Open
Abstract
Membrane proteins such as G protein-coupled receptors (GPCRs) exert fundamental biological functions and are involved in a multitude of physiological responses, making these receptors ideal drug targets. Drug discovery programs targeting GPCRs have been greatly facilitated by the emergence of high-resolution structures and the resulting opportunities to identify new chemical entities through structure-based drug design. To enable the determination of high-resolution structures of GPCRs, most receptors have to be engineered to overcome intrinsic hurdles such as their poor stability and low expression levels. In recent years, multiple engineering approaches have been developed to specifically address the technical difficulties of working with GPCRs, which are now beginning to make more challenging receptors accessible to detailed studies. Importantly, successfully engineered GPCRs are not only valuable in X-ray crystallography, but further enable biophysical studies with nuclear magnetic resonance spectroscopy, surface plasmon resonance, native mass spectrometry, and fluorescence anisotropy measurements, all of which are important for the detailed mechanistic understanding, which is the prerequisite for successful drug design. Here, we summarize engineering strategies based on directed evolution to reduce workload and enable biophysical experiments of particularly challenging GPCRs.
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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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35
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Krug U, Gloge A, Schmidt P, Becker‐Baldus J, Bernhard F, Kaiser A, Montag C, Gauglitz M, Vishnivetskiy SA, Gurevich VV, Beck‐Sickinger AG, Glaubitz C, Huster D. The Conformational Equilibrium of the Neuropeptide Y2 Receptor in Bilayer Membranes. Angew Chem Int Ed Engl 2020; 59:23854-23861. [PMID: 32790043 PMCID: PMC7736470 DOI: 10.1002/anie.202006075] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Revised: 07/13/2020] [Indexed: 12/23/2022]
Abstract
Dynamic structural transitions within the seven-transmembrane bundle represent the mechanism by which G-protein-coupled receptors convert an extracellular chemical signal into an intracellular biological function. Here, the conformational dynamics of the neuropeptide Y receptor type 2 (Y2R) during activation was investigated. The apo, full agonist-, and arrestin-bound states of Y2R were prepared by cell-free expression, functional refolding, and reconstitution into lipid membranes. To study conformational transitions between these states, all six tryptophans of Y2R were 13 C-labeled. NMR-signal assignment was achieved by dynamic-nuclear-polarization enhancement and the individual functional states of the receptor were characterized by monitoring 13 C NMR chemical shifts. Activation of Y2R is mediated by molecular switches involving the toggle switch residue Trp2816.48 of the highly conserved SWLP motif and Trp3277.55 adjacent to the NPxxY motif. Furthermore, a conformationally preserved "cysteine lock"-Trp11623.50 was identified.
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Affiliation(s)
- Ulrike Krug
- Institute of Medical Physics and BiophysicsUniversity of LeipzigHärtelstr. 16–1804107LeipzigGermany
| | - Anika Gloge
- Institute of Medical Physics and BiophysicsUniversity of LeipzigHärtelstr. 16–1804107LeipzigGermany
| | - Peter Schmidt
- Institute of Medical Physics and BiophysicsUniversity of LeipzigHärtelstr. 16–1804107LeipzigGermany
| | - Johanna Becker‐Baldus
- Institute of Biophysical ChemistryGoethe University FrankfurtGermany
- Center for Biomolecular Magnetic ResonanceGoethe University FrankfurtGermany
| | - Frank Bernhard
- Institute of Biophysical ChemistryGoethe University FrankfurtGermany
- Center for Biomolecular Magnetic ResonanceGoethe University FrankfurtGermany
| | - Anette Kaiser
- Institute of BiochemistryUniversity of LeipzigLeipzigGermany
| | - Cindy Montag
- Institute of Medical Physics and BiophysicsUniversity of LeipzigHärtelstr. 16–1804107LeipzigGermany
| | - Marcel Gauglitz
- Institute of Medical Physics and BiophysicsUniversity of LeipzigHärtelstr. 16–1804107LeipzigGermany
- Berlin Joint Electron Paramagnetic Resonance LaboratoryFree University BerlinGermany
| | | | | | | | - Clemens Glaubitz
- Institute of Biophysical ChemistryGoethe University FrankfurtGermany
- Center for Biomolecular Magnetic ResonanceGoethe University FrankfurtGermany
| | - Daniel Huster
- Institute of Medical Physics and BiophysicsUniversity of LeipzigHärtelstr. 16–1804107LeipzigGermany
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36
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Krug U, Gloge A, Schmidt P, Becker‐Baldus J, Bernhard F, Kaiser A, Montag C, Gauglitz M, Vishnivetskiy SA, Gurevich VV, Beck‐Sickinger AG, Glaubitz C, Huster D. Das Konformationsgleichgewicht des Neuropeptid‐Y2‐Rezeptors in Lipidmembranen. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202006075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Ulrike Krug
- Institut für Medizinische Physik und Biophysik Universität Leipzig Härtelstr. 16–18 04107 Leipzig Deutschland
| | - Anika Gloge
- Institut für Medizinische Physik und Biophysik Universität Leipzig Härtelstr. 16–18 04107 Leipzig Deutschland
| | - Peter Schmidt
- Institut für Medizinische Physik und Biophysik Universität Leipzig Härtelstr. 16–18 04107 Leipzig Deutschland
| | - Johanna Becker‐Baldus
- Institut für Biophysikalische Chemie Goethe-Universität Frankfurt am Main Deutschland
- Zentrum für Biomolekulare Magnetresonanz Goethe-Universität Frankfurt am Main Deutschland
| | - Frank Bernhard
- Institut für Biophysikalische Chemie Goethe-Universität Frankfurt am Main Deutschland
- Zentrum für Biomolekulare Magnetresonanz Goethe-Universität Frankfurt am Main Deutschland
| | - Anette Kaiser
- Institut für Biochemie Universität Leipzig Deutschland
| | - Cindy Montag
- Institut für Medizinische Physik und Biophysik Universität Leipzig Härtelstr. 16–18 04107 Leipzig Deutschland
| | - Marcel Gauglitz
- Institut für Medizinische Physik und Biophysik Universität Leipzig Härtelstr. 16–18 04107 Leipzig Deutschland
- Berlin Joint Electron Paramagnetic Resonance Laboratory Freie Universität Berlin Deutschland
| | | | | | | | - Clemens Glaubitz
- Institut für Biophysikalische Chemie Goethe-Universität Frankfurt am Main Deutschland
- Zentrum für Biomolekulare Magnetresonanz Goethe-Universität Frankfurt am Main Deutschland
| | - Daniel Huster
- Institut für Medizinische Physik und Biophysik Universität Leipzig Härtelstr. 16–18 04107 Leipzig Deutschland
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GPCR Activation States Induced by Nanobodies and Mini-G Proteins Compared by NMR Spectroscopy. MOLECULES (BASEL, SWITZERLAND) 2020; 25:molecules25245984. [PMID: 33348734 PMCID: PMC7767065 DOI: 10.3390/molecules25245984] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/02/2020] [Revised: 12/04/2020] [Accepted: 12/14/2020] [Indexed: 12/12/2022]
Abstract
In this work, we examine methyl nuclear magnetic resonance (NMR) spectra of the methionine ε-[13CH3] labelled thermostabilized β1 adrenergic receptor from turkey in association with a variety of different effectors, including mini-Gs and nanobody 60 (Nb60), which have not been previously studied in complex with β1 adrenergic receptor (β1AR) by NMR. Complexes with pindolol and Nb60 induce highly similar inactive states of the receptor, closely resembling the resting state conformational ensemble. We show that, upon binding of mini-Gs or nanobody 80 (Nb80), large allosteric changes throughout the receptor take place. The conformation of tβ1AR stabilized by the native-like mini-Gs protein is highly similar to the conformation induced by the currently used surrogate Nb80. Interestingly, in both cases residual dynamics are present, which were not observed in the resting states. Finally, we reproduce a pharmaceutically relevant situation, where an antagonist abolishes the interaction of the receptor with the mini-G protein in a competitive manner, validating the functional integrity of our preparation. The presented system is therefore well suited for reproducing the individual steps of the activation cycle of a G protein-coupled receptor (GPCR) in vitro and serves as a basis for functional and pharmacological characterizations of more native-like systems in the future.
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38
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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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39
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Yeh V, Goode A, Bonev BB. Membrane Protein Structure Determination and Characterisation by Solution and Solid-State NMR. BIOLOGY 2020; 9:E396. [PMID: 33198410 PMCID: PMC7697852 DOI: 10.3390/biology9110396] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Revised: 11/08/2020] [Accepted: 11/11/2020] [Indexed: 12/25/2022]
Abstract
Biological membranes define the interface of life and its basic unit, the cell. Membrane proteins play key roles in membrane functions, yet their structure and mechanisms remain poorly understood. Breakthroughs in crystallography and electron microscopy have invigorated structural analysis while failing to characterise key functional interactions with lipids, small molecules and membrane modulators, as well as their conformational polymorphism and dynamics. NMR is uniquely suited to resolving atomic environments within complex molecular assemblies and reporting on membrane organisation, protein structure, lipid and polysaccharide composition, conformational variations and molecular interactions. The main challenge in membrane protein studies at the atomic level remains the need for a membrane environment to support their fold. NMR studies in membrane mimetics and membranes of increasing complexity offer close to native environments for structural and molecular studies of membrane proteins. Solution NMR inherits high resolution from small molecule analysis, providing insights from detergent solubilised proteins and small molecular assemblies. Solid-state NMR achieves high resolution in membrane samples through fast sample spinning or sample alignment. Recent developments in dynamic nuclear polarisation NMR allow signal enhancement by orders of magnitude opening new opportunities for expanding the applications of NMR to studies of native membranes and whole cells.
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Affiliation(s)
| | | | - Boyan B. Bonev
- School of Life Sciences, University of Nottingham, Nottingham NG7 2UH, UK; (V.Y.); (A.G.)
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40
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Goba I, Goricanec D, Schum D, Hillenbrand M, Plückthun A, Hagn F. Probing the Conformation States of Neurotensin Receptor 1 Variants by NMR Site-Directed Methyl Labeling. Chembiochem 2020; 22:139-146. [PMID: 32881260 PMCID: PMC7821118 DOI: 10.1002/cbic.202000541] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Revised: 09/02/2020] [Indexed: 12/11/2022]
Abstract
G protein‐coupled receptors (GPCRs) are key players in mediating signal transduction across the cell membrane. However, due to their intrinsic instability, many GPCRs are not suitable for structural investigations. Various approaches have been developed in recent years to remedy this situation, ranging from the use of more native membrane mimetics to protein‐stabilization methods. The latter approach typically results in GPCRs that contain various numbers of mutations. However, probing the functionality of such variants by in vitro and in vivo assays is often time consuming. In addition, to validate the suitability of such GPCRs for structural investigations, an assessment of their conformation state is required. NMR spectroscopy has been proven to be suitable to probe the conformation state of GPCRs in solution. Here, by using chemical labeling with an isotope‐labeled methyl probe, we show that the activity and the conformation state of stabilized neurotensin receptor 1 variants obtained from directed evolution can be efficiently assayed in 2D NMR experiments. This strategy enables the quantification of the active and inactive conformation states and the derivation of an estimation of the basal as well as agonist‐induced activity of the receptor. Furthermore, this assay can be used as a readout when re‐introducing agonist‐dependent signaling into a highly stabilized, and thus rigidified, receptor by mutagenesis. This approach will be useful in cases where low production yields do not permit the addition of labeled compounds to the growth medium and where 1D NMR spectra of selectively 19F‐labeled receptors are not sufficient to resolve signal overlap for a more detailed analysis.
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Affiliation(s)
- Inguna Goba
- Institute of Structural Biology, Helmholtz Zentrum München, Ingolstädter Landstrasse 1, 85746, Oberschleißheim Neuherberg, Germany
| | - David Goricanec
- Bavarian NMR Center at the Department of Chemistry, Technical University of Munich, Ernst-Otto-Fischer-Strasse 2, 85747, Garching, Germany
| | - Dominik Schum
- Bavarian NMR Center at the Department of Chemistry, Technical University of Munich, Ernst-Otto-Fischer-Strasse 2, 85747, Garching, Germany
| | - Matthias Hillenbrand
- Biochemisches Institut, University of Zürich, Winterthurerstrasse 190, 8057, Zürich, Switzerland
| | - Andreas Plückthun
- Biochemisches Institut, University of Zürich, Winterthurerstrasse 190, 8057, Zürich, Switzerland
| | - Franz Hagn
- Institute of Structural Biology, Helmholtz Zentrum München, Ingolstädter Landstrasse 1, 85746, Oberschleißheim Neuherberg, Germany.,Bavarian NMR Center at the Department of Chemistry, Technical University of Munich, Ernst-Otto-Fischer-Strasse 2, 85747, Garching, Germany
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41
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Pacull EM, Sendker F, Bernhard F, Scheidt HA, Schmidt P, Huster D, Krug U. Integration of Cell-Free Expression and Solid-State NMR to Investigate the Dynamic Properties of Different Sites of the Growth Hormone Secretagogue Receptor. Front Pharmacol 2020; 11:562113. [PMID: 33324203 PMCID: PMC7723455 DOI: 10.3389/fphar.2020.562113] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Accepted: 09/21/2020] [Indexed: 01/09/2023] Open
Abstract
Cell-free expression represents an attractive method to produce large quantities of selectively labeled protein for NMR applications. Here, cell-free expression was used to label specific regions of the growth hormone secretagogue receptor (GHSR) with NMR-active isotopes. The GHSR is a member of the class A family of G protein-coupled receptors. A cell-free expression system was established to produce the GHSR in the precipitated form. The solubilized receptor was refolded in vitro and reconstituted into DMPC lipid membranes. Methionines, arginines, and histidines were chosen for 13C-labeling as they are representative for the transmembrane domains, the loops and flanking regions of the transmembrane α-helices, and the C-terminus of the receptor, respectively. The dynamics of the isotopically labeled residues was characterized by solid-state NMR measuring motionally averaged 1H-13C dipolar couplings, which were converted into molecular order parameters. Separated local field DIPSHIFT experiments under magic-angle spinning conditions using either varying cross polarization contact times or direct excitation provided order parameters for these residues showing that the C-terminus was the segment with the highest motional amplitude. The loop regions and helix ends as well as the transmembrane regions of the GHSR represent relatively rigid segments in the overall very flexible receptor molecule. Although no site resolution could be achieved in the experiments, the previously reported highly dynamic character of the receptor concluded from uniformly 13C labeled receptor samples could be further specified by this segmental labeling approach, leading to a more diversified understanding of the receptor dynamics under equilibrium conditions.
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Affiliation(s)
- Emelyne M Pacull
- Institute for Medical Physics and Biophysics, University of Leipzig, Leipzig, Germany
| | - Franziska Sendker
- Institute for Medical Physics and Biophysics, University of Leipzig, Leipzig, Germany
| | - Frank Bernhard
- Institute of Biophysical Chemistry, Goethe University Frankfurt, Frankfurt am Main, Germany.,Center for Biomolecular Magnetic Resonance, Goethe University Frankfurt, Frankfurt am Main, Germany
| | - Holger A Scheidt
- Institute for Medical Physics and Biophysics, University of Leipzig, Leipzig, Germany
| | - Peter Schmidt
- Institute for Medical Physics and Biophysics, University of Leipzig, Leipzig, Germany
| | - Daniel Huster
- Institute for Medical Physics and Biophysics, University of Leipzig, Leipzig, Germany
| | - Ulrike Krug
- Institute for Medical Physics and Biophysics, University of Leipzig, Leipzig, Germany
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42
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Rößler P, Mathieu D, Gossert AD. NMR‐Studien an biologischen Makromolekülen (>100 kDa) ohne Notwendigkeit der Deuterierung: Das XL‐ALSOFAST Experiment mit verzögerter Entkopplung. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202007715] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Philip Rößler
- Institut für Molekularbiologie und Biophysik Department Biologie und Biomolekulare NMR Spektroskopie Plattform Department Biologie ETH Zürich Otto-Stern-Weg 5 8093 Zürich Schweiz
| | - Daniel Mathieu
- Bruker BioSpin GmbH Silberstreifen 4 76287 Rheinstetten Deutschland
| | - Alvar D. Gossert
- Institut für Molekularbiologie und Biophysik Department Biologie und Biomolekulare NMR Spektroskopie Plattform Department Biologie ETH Zürich Otto-Stern-Weg 5 8093 Zürich Schweiz
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43
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Rößler P, Mathieu D, Gossert AD. Enabling NMR Studies of High Molecular Weight Systems Without the Need for Deuteration: The XL-ALSOFAST Experiment with Delayed Decoupling. Angew Chem Int Ed Engl 2020; 59:19329-19337. [PMID: 32743971 PMCID: PMC7589290 DOI: 10.1002/anie.202007715] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Indexed: 11/30/2022]
Abstract
Current biological research increasingly focusses on large human proteins and their complexes. Such proteins are difficult to study by NMR spectroscopy because they often can only be produced in higher eukaryotic expression systems, where deuteration is hardly feasible. Here, we present the XL-ALSOFAST-[13 C,1 H]-HMQC experiment with much improved sensitivity for fully protonated high molecular weight proteins. For the tested systems ranging from 100 to 240 kDa in size, 3-fold higher sensitivity was obtained on average for fast relaxing signals compared to current state-of-the-art experiments. In the XL-ALSOFAST approach, non-observed magnetisation is optimally exploited and transverse relaxation is minimized by the newly introduced concept of delayed decoupling. The combination of high sensitivity and superior artefact suppression makes it ideal for studying inherently unstable membrane proteins or for analysing therapeutic antibodies at natural 13 C abundance. The XL-ALSOFAST and delayed decoupling will therefore expand the range of biomolecular systems accessible to NMR spectroscopy.
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Affiliation(s)
- Philip Rößler
- Institute of Molecular Biology and BiophysicsDepartment of Biology and Biomolecular NMR Spectroscopy PlatformDepartment of BiologyETH ZürichOtto-Stern-Weg 58093ZürichSwitzerland
| | - Daniel Mathieu
- Bruker BioSpin GmbHSilberstreifen 476287RheinstettenGermany
| | - Alvar D. Gossert
- Institute of Molecular Biology and BiophysicsDepartment of Biology and Biomolecular NMR Spectroscopy PlatformDepartment of BiologyETH ZürichOtto-Stern-Weg 58093ZürichSwitzerland
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44
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Jones AJY, Gabriel F, Tandale A, Nietlispach D. Structure and Dynamics of GPCRs in Lipid Membranes: Physical Principles and Experimental Approaches. Molecules 2020; 25:E4729. [PMID: 33076366 PMCID: PMC7587580 DOI: 10.3390/molecules25204729] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Revised: 10/11/2020] [Accepted: 10/12/2020] [Indexed: 02/06/2023] Open
Abstract
Over the past decade, the vast amount of information generated through structural and biophysical studies of GPCRs has provided unprecedented mechanistic insight into the complex signalling behaviour of these receptors. With this recent information surge, it has also become increasingly apparent that in order to reproduce the various effects that lipids and membranes exert on the biological function for these allosteric receptors, in vitro studies of GPCRs need to be conducted under conditions that adequately approximate the native lipid bilayer environment. In the first part of this review, we assess some of the more general effects that a membrane environment exerts on lipid bilayer-embedded proteins such as GPCRs. This is then followed by the consideration of more specific effects, including stoichiometric interactions with specific lipid subtypes. In the final section, we survey a range of different membrane mimetics that are currently used for in vitro studies, with a focus on NMR applications.
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Affiliation(s)
| | | | | | - Daniel Nietlispach
- Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge CB2 1GA, UK; (A.J.Y.J.); (F.G.); (A.T.)
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45
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Capturing Peptide-GPCR Interactions and Their Dynamics. Molecules 2020; 25:molecules25204724. [PMID: 33076289 PMCID: PMC7587574 DOI: 10.3390/molecules25204724] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Revised: 10/08/2020] [Accepted: 10/09/2020] [Indexed: 12/16/2022] Open
Abstract
Many biological functions of peptides are mediated through G protein-coupled receptors (GPCRs). Upon ligand binding, GPCRs undergo conformational changes that facilitate the binding and activation of multiple effectors. GPCRs regulate nearly all physiological processes and are a favorite pharmacological target. In particular, drugs are sought after that elicit the recruitment of selected effectors only (biased ligands). Understanding how ligands bind to GPCRs and which conformational changes they induce is a fundamental step toward the development of more efficient and specific drugs. Moreover, it is emerging that the dynamic of the ligand–receptor interaction contributes to the specificity of both ligand recognition and effector recruitment, an aspect that is missing in structural snapshots from crystallography. We describe here biochemical and biophysical techniques to address ligand–receptor interactions in their structural and dynamic aspects, which include mutagenesis, crosslinking, spectroscopic techniques, and mass-spectrometry profiling. With a main focus on peptide receptors, we present methods to unveil the ligand–receptor contact interface and methods that address conformational changes both in the ligand and the GPCR. The presented studies highlight a wide structural heterogeneity among peptide receptors, reveal distinct structural changes occurring during ligand binding and a surprisingly high dynamics of the ligand–GPCR complexes.
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46
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Probing the Y 2 Receptor on Transmembrane, Intra- and Extra-Cellular Sites for EPR Measurements. Molecules 2020; 25:molecules25184143. [PMID: 32927734 PMCID: PMC7571237 DOI: 10.3390/molecules25184143] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Revised: 09/04/2020] [Accepted: 09/09/2020] [Indexed: 02/07/2023] Open
Abstract
The function of G protein-coupled receptors is intrinsically linked to their conformational dynamics. In conjugation with site-directed spin labeling, electron paramagnetic resonance (EPR) spectroscopy provides powerful tools to study the highly dynamic conformational states of these proteins. Here, we explored positions for nitroxide spin labeling coupled to single cysteines, introduced at transmembrane, intra- and extra-cellular sites of the human neuropeptide Y2 receptor. Receptor mutants were functionally analyzed in cell culture system, expressed in Escherichia coli fermentation with yields of up to 10 mg of purified protein per liter expression medium and functionally reconstituted into a lipid bicelle environment. Successful spin labeling was confirmed by a fluorescence assay and continuous wave EPR measurements. EPR spectra revealed mobile and immobile populations, indicating multiple dynamic conformational states of the receptor. We found that the singly mutated positions by MTSL ((1-oxyl-2,2,5,5-tetramethyl-2,5-dihydro-1H-pyrrol-3-yl) methyl methanesulfonothioate) have a water exposed immobilized conformation as their main conformation, while in case of the IDSL (bis(1-oxyl-2,2,5,5-tetramethyl-3-imidazolin-4-yl) disulfide) labeled positions, the main conformation are mainly of hydrophobic nature. Further, double cysteine mutants were generated and examined for potential applications of distance measurements by double electron–electron resonance (DEER) pulsed EPR technique on the receptor.
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47
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Wingler LM, Lefkowitz RJ. Conformational Basis of G Protein-Coupled Receptor Signaling Versatility. Trends Cell Biol 2020; 30:736-747. [PMID: 32622699 PMCID: PMC7483927 DOI: 10.1016/j.tcb.2020.06.002] [Citation(s) in RCA: 133] [Impact Index Per Article: 33.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Revised: 06/07/2020] [Accepted: 06/08/2020] [Indexed: 12/19/2022]
Abstract
G protein-coupled receptors (GPCRs) are privileged structural scaffolds in biology that have the versatility to regulate diverse physiological processes. Interestingly, many GPCR ligands exhibit significant 'bias' - the ability to preferentially activate subsets of the many cellular pathways downstream of these receptors. Recently, complementary information from structural and spectroscopic approaches has made significant inroads into understanding the mechanisms of these biased ligands. The consistently emerging theme is that GPCRs are highly dynamic proteins, and ligands with varying pharmacological properties differentially modulate the equilibrium among multiple conformations. Biased signaling and other recently appreciated complexities of GPCR signaling thus appear to be a natural consequence of the conformational heterogeneity of GPCRs and GPCR-transducer complexes.
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Affiliation(s)
- Laura M Wingler
- Howard Hughes Medical Institute and Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA.
| | - Robert J Lefkowitz
- Howard Hughes Medical Institute and Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA; Department of Biochemistry, Duke University Medical Center, Durham, NC 27710, USA.
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48
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Hothersall JD, Jones AY, Dafforn TR, Perrior T, Chapman KL. Releasing the technical 'shackles' on GPCR drug discovery: opportunities enabled by detergent-free polymer lipid particle (PoLiPa) purification. Drug Discov Today 2020; 25:S1359-6446(20)30337-8. [PMID: 32835806 DOI: 10.1016/j.drudis.2020.08.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Revised: 07/04/2020] [Accepted: 08/13/2020] [Indexed: 12/19/2022]
Abstract
G-protein-coupled receptor (GPCR) drug research is presently hindered by the technical challenges associated with generating purified receptors. Consequently, the application of critical modern discovery technologies has been limited, and the vast untapped opportunity for new GPCR-directed medicines is not being realised. A simple but transformative solution is to purify receptors without removing them from their native phospholipid environment by using polymer lipid particle (PoLiPa) technology, with reagents such as styrene-maleic acid co-polymer (SMA). Compared with contemporary detergent-based and stabilising mutagenesis methods, the PoLiPa approach is simple and generic and, therefore, offers huge advantages, with the potential to revolutionise GPCR research by facilitating the availability of the purified receptors that are required for structural biology, biophysical, and panning technologies.
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Affiliation(s)
- J Daniel Hothersall
- Domainex Ltd, Chesterford Research Park, Little Chesterford, Saffron Walden, CB10 1XL, UK.
| | - Andrew Y Jones
- Domainex Ltd, Chesterford Research Park, Little Chesterford, Saffron Walden, CB10 1XL, UK
| | - Tim R Dafforn
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK
| | - Trevor Perrior
- Domainex Ltd, Chesterford Research Park, Little Chesterford, Saffron Walden, CB10 1XL, UK
| | - Kathryn L Chapman
- Domainex Ltd, Chesterford Research Park, Little Chesterford, Saffron Walden, CB10 1XL, UK
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49
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Pritišanac I, Alderson TR, Güntert P. Automated assignment of methyl NMR spectra from large proteins. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2020; 118-119:54-73. [PMID: 32883449 DOI: 10.1016/j.pnmrs.2020.04.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Revised: 04/15/2020] [Accepted: 04/17/2020] [Indexed: 05/05/2023]
Abstract
As structural biology trends towards larger and more complex biomolecular targets, a detailed understanding of their interactions and underlying structures and dynamics is required. The development of methyl-TROSY has enabled NMR spectroscopy to provide atomic-resolution insight into the mechanisms of large molecular assemblies in solution. However, the applicability of methyl-TROSY has been hindered by the laborious and time-consuming resonance assignment process, typically performed with domain fragmentation, site-directed mutagenesis, and analysis of NOE data in the context of a crystal structure. In response, several structure-based automatic methyl assignment strategies have been developed over the past decade. Here, we present a comprehensive analysis of all available methods and compare their input data requirements, algorithmic strategies, and reported performance. In general, the methods fall into two categories: those that primarily rely on inter-methyl NOEs, and those that utilize methyl PRE- and PCS-based restraints. We discuss their advantages and limitations, and highlight the potential benefits from standardizing and combining different methods.
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Affiliation(s)
- Iva Pritišanac
- Institute of Biophysical Chemistry, Center for Biomolecular Magnetic Resonance, Goethe University Frankfurt am Main, 60438 Frankfurt am Main, Germany
| | - T Reid Alderson
- Laboratory of Chemical Physics, NIDDK, National Institutes of Health, Bethesda, MD 20892, USA
| | - Peter Güntert
- Institute of Biophysical Chemistry, Center for Biomolecular Magnetic Resonance, Goethe University Frankfurt am Main, 60438 Frankfurt am Main, Germany; Laboratory of Physical Chemistry, ETH Zürich, 8093 Zürich, Switzerland; Department of Chemistry, Tokyo Metropolitan University, Hachioji, Tokyo 192-0397, Japan.
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50
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Wu FJ, Williams LM, Abdul-Ridha A, Gunatilaka A, Vaid TM, Kocan M, Whitehead AR, Griffin MDW, Bathgate RAD, Scott DJ, Gooley PR. Probing the correlation between ligand efficacy and conformational diversity at the α 1A-adrenoreceptor reveals allosteric coupling of its microswitches. J Biol Chem 2020; 295:7404-7417. [PMID: 32303636 PMCID: PMC7247315 DOI: 10.1074/jbc.ra120.012842] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 04/14/2020] [Indexed: 12/11/2022] Open
Abstract
G protein-coupled receptors (GPCRs) use a series of conserved microswitches to transmit signals across the cell membrane via an allosteric network encompassing the ligand-binding site and the G protein-binding site. Crystal structures of GPCRs provide snapshots of their inactive and active states, but poorly describe the conformational dynamics of the allosteric network that underlies GPCR activation. Here, we analyzed the correlation between ligand binding and receptor conformation of the α1A-adrenoreceptor, a GPCR that stimulates smooth muscle contraction in response to binding noradrenaline. NMR of [13CϵH3]methionine-labeled α1A-adrenoreceptor variants, each exhibiting differing signaling capacities, revealed how different classes of ligands modulate the conformational equilibria of this receptor. [13CϵH3]Methionine residues near the microswitches exhibited distinct states that correlated with ligand efficacies, supporting a conformational selection mechanism. We propose that allosteric coupling among the microswitches controls the conformation of the α1A-adrenoreceptor and underlies the mechanism of ligand modulation of GPCR signaling in cells.
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Affiliation(s)
- Feng-Jie Wu
- Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville 3052, VIC, Australia; Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville 3052, VIC, Australia; The Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville 3052, VIC, Australia
| | - Lisa M Williams
- The Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville 3052, VIC, Australia
| | - Alaa Abdul-Ridha
- The Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville 3052, VIC, Australia
| | - Avanka Gunatilaka
- The Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville 3052, VIC, Australia
| | - Tasneem M Vaid
- Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville 3052, VIC, Australia; Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville 3052, VIC, Australia; The Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville 3052, VIC, Australia
| | - Martina Kocan
- The Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville 3052, VIC, Australia
| | - Alice R Whitehead
- The Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville 3052, VIC, Australia
| | - Michael D W Griffin
- Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville 3052, VIC, Australia; Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville 3052, VIC, Australia
| | - Ross A D Bathgate
- Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville 3052, VIC, Australia; The Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville 3052, VIC, Australia
| | - Daniel J Scott
- Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville 3052, VIC, Australia; The Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville 3052, VIC, Australia.
| | - Paul R Gooley
- Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville 3052, VIC, Australia; Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville 3052, VIC, Australia.
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