151
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Puthenveetil R, Christenson ET, Vinogradova O. New Horizons in Structural Biology of Membrane Proteins: Experimental Evaluation of the Role of Conformational Dynamics and Intrinsic Flexibility. MEMBRANES 2022; 12:227. [PMID: 35207148 PMCID: PMC8877495 DOI: 10.3390/membranes12020227] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Revised: 02/13/2022] [Accepted: 02/14/2022] [Indexed: 02/08/2023]
Abstract
A plethora of membrane proteins are found along the cell surface and on the convoluted labyrinth of membranes surrounding organelles. Since the advent of various structural biology techniques, a sub-population of these proteins has become accessible to investigation at near-atomic resolutions. The predominant bona fide methods for structure solution, X-ray crystallography and cryo-EM, provide high resolution in three-dimensional space at the cost of neglecting protein motions through time. Though structures provide various rigid snapshots, only an amorphous mechanistic understanding can be inferred from interpolations between these different static states. In this review, we discuss various techniques that have been utilized in observing dynamic conformational intermediaries that remain elusive from rigid structures. More specifically we discuss the application of structural techniques such as NMR, cryo-EM and X-ray crystallography in studying protein dynamics along with complementation by conformational trapping by specific binders such as antibodies. We finally showcase the strength of various biophysical techniques including FRET, EPR and computational approaches using a multitude of succinct examples from GPCRs, transporters and ion channels.
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Affiliation(s)
- Robbins Puthenveetil
- Section on Structural and Chemical Biology of Membrane Proteins, Neurosciences and Cellular and Structural Biology Division, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, 35A Convent Dr., Bethesda, MD 20892, USA
| | | | - Olga Vinogradova
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Connecticut, Storrs, CT 06269, USA
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152
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Liccardo F, Luini A, Di Martino R. Endomembrane-Based Signaling by GPCRs and G-Proteins. Cells 2022; 11:528. [PMID: 35159337 PMCID: PMC8834376 DOI: 10.3390/cells11030528] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2021] [Revised: 01/26/2022] [Accepted: 01/28/2022] [Indexed: 12/14/2022] Open
Abstract
G-protein-coupled receptors (GPCRs) and G-proteins have a range of roles in many physiological and pathological processes and are among the most studied signaling proteins. A plethora of extracellular stimuli can activate the GPCR and can elicit distinct intracellular responses through the activation of specific transduction pathways. For many years, biologists thought that GPCR signaling occurred entirely on the plasma membrane. However, in recent decades, many lines of evidence have proved that the GPCRs and G-proteins may reside on endomembranes and can start or propagate signaling pathways through the organelles that form the secretory route. How these alternative intracellular signaling pathways of the GPCR and G-proteins influence the physiological and pathological function of the endomembranes is still under investigation. Here, we review the general role and classification of GPCRs and G-proteins with a focus on their signaling pathways in the membrane transport apparatus.
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Affiliation(s)
- Federica Liccardo
- Cardiovascular Research Institute, University of California San Francisco (UCSF), 555 Mission Bay Blvd., San Francisco, CA 94158, USA;
| | - Alberto Luini
- Istituto per L’endocrinologia e L’oncologia Sperimentale “Gaetano Salvatore” (IEOS)—Sede Secondaria, Via Pietro Castellino 111, 80131 Napoli, Italy
| | - Rosaria Di Martino
- Istituto per L’endocrinologia e L’oncologia Sperimentale “Gaetano Salvatore” (IEOS)—Sede Secondaria, Via Pietro Castellino 111, 80131 Napoli, Italy
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153
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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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154
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Joshi M, Nikte SV, Sengupta D. Molecular determinants of GPCR pharmacogenetics: Deconstructing the population variants in β 2-adrenergic receptor. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2022; 128:361-396. [PMID: 35034724 DOI: 10.1016/bs.apcsb.2021.08.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
G protein-coupled receptors (GPCRs) are membrane proteins that play a central role in cell signaling and constitute one of the largest classes of drug targets. The molecular mechanisms underlying GPCR function have been characterized by several experimental and computational methods and provide an understanding of their role in physiology and disease. Population variants arising from nsSNPs affect the native function of GPCRs and have been implicated in differential drug response. In this chapter, we provide an overview on GPCR structure and activation, with a special focus on the β2-adrenergic receptor (β2-AR). First, we discuss the current understanding of the structural and dynamic features of the wildtype receptor. Subsequently, the population variants identified in this receptor from clinical and large-scale genomic studies are described. We show how computational approaches such as bioinformatics tools and molecular dynamics simulations can be used to characterize the variant receptors in comparison to the wildtype receptor. In particular, we discuss three examples of clinically important variants and discuss how the structure and function of these variants differ from the wildtype receptor at a molecular level. Overall, the chapter provides an overview of structure and function of GPCR variants and is a step towards the study of inter-individual differences and personalized medicine.
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Affiliation(s)
- Manali Joshi
- Bioinformatics Centre, Savitribai Phule Pune University, Pune, India.
| | - Siddhanta V Nikte
- CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, Pune, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India
| | - Durba Sengupta
- CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, Pune, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India.
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155
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Liu B, Yang D. Easily Established and Multifunctional Synthetic Nanobody Libraries as Research Tools. Int J Mol Sci 2022; 23:ijms23031482. [PMID: 35163405 PMCID: PMC8835997 DOI: 10.3390/ijms23031482] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Revised: 01/19/2022] [Accepted: 01/25/2022] [Indexed: 02/06/2023] Open
Abstract
Nanobodies, or VHHs, refer to the antigen-binding domain of heavy-chain antibodies (HCAbs) from camelids. They have been widely used as research tools for protein purification and structure determination due to their small size, high specificity, and high stability, overcoming limitations with conventional antibody fragments. However, animal immunization and subsequent retrieval of antigen-specific nanobodies are expensive and complicated. Construction of synthetic nanobody libraries using DNA oligonucleotides is a cost-effective alternative for immunization libraries and shows great potential in identifying antigen-specific or even conformation-specific nanobodies. This review summarizes and analyses synthetic nanobody libraries in the current literature, including library design and biopanning methods, and further discusses applications of antigen-specific nanobodies obtained from synthetic libraries to research.
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156
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Lee D, Kwon HB. Current and future techniques for detecting oxytocin: Focusing on genetically-encoded GPCR sensors. J Neurosci Methods 2022; 366:109407. [PMID: 34763021 DOI: 10.1016/j.jneumeth.2021.109407] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 10/12/2021] [Accepted: 11/03/2021] [Indexed: 10/19/2022]
Abstract
Oxytocin is a neuropituitary hormone that is involved in a wide range of psychosocial behaviors. Despite its psychophysiological importance as a neuromodulator in the CNS, effective techniques capable of monitoring oxytocin dynamics or testing related behavioral consequences are limited. Along with an explosive advancement in synthetic biology, high-performance genetically-encoded neuromodulator sensors are being developed. Here we comprehensively review the current methodologies available for detecting oxytocin in neuroscience. Their strengths and weaknesses are discussed, and a graphical summary is plotted for better comparison of techniques. We also suggest future directions for next generation oxytocin sensor development and their working principles.
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Affiliation(s)
- Dongmin Lee
- Department of Anatomy, Korea University College of Medicine, Seoul, Republic of Korea; BK21 Graduate Program, Department of Biomedical Sciences, Korea University College of Medicine, Seoul, Republic of Korea
| | - Hyung-Bae Kwon
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, 733N Broadway, Baltimore, MD 21205, USA.
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157
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Cai J, Romão E, Wu G, Li J, Li L, Wang Z, Li Y, Yang J, Shen Y, Xu Z, Muyldermans S, Wang H. Nanobodies as binding-chaperones stabilize the recombinant Bombyx mori acetylcholinesterase and protect the enzyme activity in pesticide detection. Enzyme Microb Technol 2022; 155:109992. [DOI: 10.1016/j.enzmictec.2022.109992] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Revised: 01/02/2022] [Accepted: 01/05/2022] [Indexed: 11/03/2022]
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158
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Matsuzaki Y, Kajiwara K, Aoki W, Ueda M. Production of Single-Domain Antibodies in Pichia pastoris. Methods Mol Biol 2022; 2446:181-203. [PMID: 35157274 DOI: 10.1007/978-1-0716-2075-5_9] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Single-domain antibodies (sdAbs) are binders that consist of a single immunoglobulin domain. SdAbs have gained importance as therapeutics, diagnostic reagents, and research tools. Functional sdAbs are commonly produced in Escherichia coli, which is a simple and widely used host for production of recombinant proteins. However, there are drawbacks of the E. coli expression system, including the potential for misfolded recombinant proteins and pyrogenic contamination with toxic lipopolysaccharides. Pichia pastoris is an alternative host for the production of heterologous proteins because of its high recombinant protein yields and the ability to produce soluble, properly folded proteins without lipopolysaccharide contamination. Here, we describe a method to produce sdAbs in P. pastoris. We present methods for the cloning of sdAb-encoding genes into a P. pastoris expression vector, production and purification of sdAbs, and measurement of sdAb-binding kinetics. Functional sdAbs are easily and routinely obtained using these methods.
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Affiliation(s)
- Yusei Matsuzaki
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto, Japan
| | - Kaho Kajiwara
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto, Japan
| | - Wataru Aoki
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto, Japan
- Core Research for Evolutionary Science and Technology (CREST), Japan Science and Technology Agency (JST), Tokyo, Japan
| | - Mitsuyoshi Ueda
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto, Japan.
- Core Research for Evolutionary Science and Technology (CREST), Japan Science and Technology Agency (JST), Tokyo, Japan.
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159
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Wang X, Ji G, Han X, Hao H, Liu W, Xue Q, Guo Q, Wang S, Lei K, Liu Y. Thiazolidinedione derivatives as novel GPR120 agonists for the treatment of type 2 diabetes. RSC Adv 2022; 12:5732-5742. [PMID: 35424534 PMCID: PMC8981563 DOI: 10.1039/d1ra08925k] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Accepted: 02/08/2022] [Indexed: 12/16/2022] Open
Abstract
GPR120, also called FFAR4, is preferentially expressed in the intestines, and can be stimulated by long-chain free fatty acids to increase the secretion of glucagon-like peptide-1 (GLP-1) from intestinal endocrine cells. It is known that GLP-1, as an incretin, can promote the insulin secretion from pancreatic cells in a glucose-dependent manner. Therefore, GPR120 is a potential drug target to treat type 2 diabetes. In this study, thiazolidinedione derivatives were found to be novel potent GPR120 agonists. Compound 5g, with excellent agonistic activity, selectivity, and metabolic stability, improved oral glucose tolerance in normal C57BL/6 mice in a dose-dependent manner. Moreover, compound 5g exhibited anti-diabetic activity by promoting insulin secretion in diet-induced obese mice. In summary, compound 5g might be a promising drug candidate for the treatment of type 2 diabetes. GPR120 has emerged as an attractive target for the treatment of type 2 diabetes and obesity. Thiazolidinedione derivatives were found to be novel potent GPR120 agonists.![]()
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Affiliation(s)
- Xuekun Wang
- School of Pharmaceutical Sciences, Liaocheng University, 1 Hunan Street, Liaocheng 252059, China
| | - Guoxia Ji
- School of Pharmaceutical Sciences, Liaocheng University, 1 Hunan Street, Liaocheng 252059, China
- School of Chemistry and Chemical Engineering, Liaocheng University, 1 Hunan Street, Liaocheng 252059, China
| | - Xinyu Han
- School of Pharmaceutical Sciences, Liaocheng University, 1 Hunan Street, Liaocheng 252059, China
| | - Huiran Hao
- School of Pharmaceutical Sciences, Liaocheng University, 1 Hunan Street, Liaocheng 252059, China
| | - Wenjing Liu
- School of Pharmaceutical Sciences, Liaocheng University, 1 Hunan Street, Liaocheng 252059, China
| | - Qidi Xue
- School of Pharmaceutical Sciences, Liaocheng University, 1 Hunan Street, Liaocheng 252059, China
| | - Qinghua Guo
- School of Pharmaceutical Sciences, Liaocheng University, 1 Hunan Street, Liaocheng 252059, China
| | - Shiben Wang
- School of Pharmaceutical Sciences, Liaocheng University, 1 Hunan Street, Liaocheng 252059, China
| | - Kang Lei
- School of Pharmaceutical Sciences, Liaocheng University, 1 Hunan Street, Liaocheng 252059, China
| | - Yadi Liu
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China
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160
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Felline A, Raimondi F, Gentile S, Fanelli F. Structural communication between the GTPase Sec4p and its activator Sec2p: Determinants of GEF activity and early deformations to nucleotide release. Comput Struct Biotechnol J 2022; 20:5162-5180. [PMID: 36187918 PMCID: PMC9508438 DOI: 10.1016/j.csbj.2022.09.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Revised: 09/08/2022] [Accepted: 09/08/2022] [Indexed: 11/29/2022] Open
Abstract
Ras GTPases are molecular switches that cycle between OFF and ON states depending on the bound nucleotide (i.e. GDP-bound and GTP-bound, respectively). The Rab GTPase, Sec4p, plays regulatory roles in multiple steps of intracellular vesicle trafficking. Nucleotide release is catalyzed by the Guanine Nucleotide Exchange Factor (GEF) Sec2p. Here, the integration of structural information with molecular dynamics (MD) simulations addressed a number of questions concerning the intrinsic and stimulated dynamics of Sec2p and Sec4p as well as the chain of structural deformations leading to GEF-assisted activation of the Rab GTPase. Sec2p holds an intrinsic ability to adopt the conformation found in the crystallographic complexes with Sec4p, thus suggesting that the latter selects and shifts the conformational equilibrium towards a pre-existing bound-like conformation of Sec2p. The anchoring of Sec4p to a suitable conformation of Sec2p favors the Sec2p-assisted pulling on itself of the α1/switch 1 (SWI) loop and of SWI, which loose any contact with GDP. Those deformations of Sec4p would occur earlier. Formation of the final Sec2p-Sec4p hydrophobic interface, accomplishes later. Disruption of the nucleotide cage would cause firstly loss of interactions with the guanine ring and secondly loss of interactions with the phosphates. The ease in sampling the energy landscape and adopting a bound-like conformation likely favors the catalyzing ability of GEFs for Ras GTPases.
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161
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Rivero-Müller A, Huhtaniemi I. Genetic variants of gonadotrophins and their receptors: Impact on the diagnosis and management of the infertile patient. Best Pract Res Clin Endocrinol Metab 2022; 36:101596. [PMID: 34802912 DOI: 10.1016/j.beem.2021.101596] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
This narrative review is concerned with genetic variants of the genes encoding gonadotrophin subunits and their receptors, as well as their implications into the diagnosis and treatment of infertility. We first review briefly the basics of molecular biology and biochemistry of gonadotrophin and gonadotrophin receptor structure and function, then describe the phenotypic effects of polymorphisms and mutations of these genes, followed by diagnostic aspects. We will then summarise the information that inactivating gonadotrophin receptor mutations have provided about the controversial topic of extragonadal gonadotrophin action. Finally, we will close with the current and future therapeutic approaches on patients with gonadotrophin and their receptor mutations.
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Affiliation(s)
- Adolfo Rivero-Müller
- Department of Biochemistry and Molecular Biology, Medical University of Lublin, Lublin, 20-093, Poland
| | - Ilpo Huhtaniemi
- Institute of Reproductive and Developmental Biology, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, W12 0NN, UK.
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162
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Chen Y, Fleetwood O, Pérez-Conesa S, Delemotte L. Allosteric Effect of Nanobody Binding on Ligand-Specific Active States of the β2 Adrenergic Receptor. J Chem Inf Model 2021; 61:6024-6037. [PMID: 34780174 PMCID: PMC8715506 DOI: 10.1021/acs.jcim.1c00826] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
![]()
Nanobody binding
stabilizes G-protein-coupled receptors (GPCR)
in a fully active state and modulates their affinity for bound ligands.
However, the atomic-level basis for this allosteric regulation remains
elusive. Here, we investigate the conformational changes induced by
the binding of a nanobody (Nb80) on the active-like β2 adrenergic
receptor (β2AR) via enhanced sampling molecular dynamics simulations.
Dimensionality reduction analysis shows that Nb80 stabilizes structural
features of the β2AR with an ∼14 Å outward movement
of transmembrane helix 6 and a close proximity of transmembrane (TM)
helices 5 and 7, and favors the fully active-like conformation of
the receptor, independent of ligand binding, in contrast to the conditions
under which no intracellular binding partner is bound, in which case
the receptor is only stabilized in an intermediate-active state. This
activation is supported by the residues located at hotspots located
on TMs 5, 6, and 7, as shown by supervised machine learning methods.
Besides, ligand-specific subtle differences in the conformations assumed
by intracellular loop 2 and extracellular loop 2 are captured from
the trajectories of various ligand-bound receptors in the presence
of Nb80. Dynamic network analysis further reveals that Nb80 binding
triggers tighter and stronger local communication networks between
the Nb80 and the ligand-binding sites, primarily involving residues
around ICL2 and the intracellular end of TM3, TM5, TM6, as well as
ECL2, ECL3, and the extracellular ends of TM6 and TM7. In particular,
we identify unique allosteric signal transmission mechanisms between
the Nb80-binding site and the extracellular domains in conformations
modulated by a full agonist, BI167107, and a G-protein-biased partial
agonist, salmeterol, involving mainly TM1 and TM2, and TM5, respectively.
Altogether, our results provide insights into the effect of intracellular
binding partners on the GPCR activation mechanism, which should be
taken into account in structure-based drug discovery.
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Affiliation(s)
- Yue Chen
- Science for Life Laboratory, Department of Applied Physics, KTH Royal Institute of Technology, SE-17121 Solna, Sweden
| | - Oliver Fleetwood
- Science for Life Laboratory, Department of Applied Physics, KTH Royal Institute of Technology, SE-17121 Solna, Sweden
| | - Sergio Pérez-Conesa
- Science for Life Laboratory, Department of Applied Physics, KTH Royal Institute of Technology, SE-17121 Solna, Sweden
| | - Lucie Delemotte
- Science for Life Laboratory, Department of Applied Physics, KTH Royal Institute of Technology, SE-17121 Solna, Sweden
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163
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Krishna Deepak RNV, Verma RK, Hartono YD, Yew WS, Fan H. Recent Advances in Structure, Function, and Pharmacology of Class A Lipid GPCRs: Opportunities and Challenges for Drug Discovery. Pharmaceuticals (Basel) 2021; 15:12. [PMID: 35056070 PMCID: PMC8779880 DOI: 10.3390/ph15010012] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 12/17/2021] [Accepted: 12/17/2021] [Indexed: 01/01/2023] Open
Abstract
Great progress has been made over the past decade in understanding the structural, functional, and pharmacological diversity of lipid GPCRs. From the first determination of the crystal structure of bovine rhodopsin in 2000, much progress has been made in the field of GPCR structural biology. The extraordinary progress in structural biology and pharmacology of GPCRs, coupled with rapid advances in computational approaches to study receptor dynamics and receptor-ligand interactions, has broadened our comprehension of the structural and functional facets of the receptor family members and has helped usher in a modern age of structure-based drug design and development. First, we provide a primer on lipid mediators and lipid GPCRs and their role in physiology and diseases as well as their value as drug targets. Second, we summarize the current advancements in the understanding of structural features of lipid GPCRs, such as the structural variation of their extracellular domains, diversity of their orthosteric and allosteric ligand binding sites, and molecular mechanisms of ligand binding. Third, we close by collating the emerging paradigms and opportunities in targeting lipid GPCRs, including a brief discussion on current strategies, challenges, and the future outlook.
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Affiliation(s)
- R. N. V. Krishna Deepak
- Bioinformatics Institute, A*STAR, 30 Biopolis Street, Matrix #07-01, Singapore 138671, Singapore; (R.K.V.); (Y.D.H.)
| | - Ravi Kumar Verma
- Bioinformatics Institute, A*STAR, 30 Biopolis Street, Matrix #07-01, Singapore 138671, Singapore; (R.K.V.); (Y.D.H.)
| | - Yossa Dwi Hartono
- Bioinformatics Institute, A*STAR, 30 Biopolis Street, Matrix #07-01, Singapore 138671, Singapore; (R.K.V.); (Y.D.H.)
- Synthetic Biology Translational Research Programme, Yong Loo Lin School of Medicine, National University of Singapore, 14 Medical Drive, Singapore 117599, Singapore;
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, 8 Medical Drive, Singapore 117597, Singapore
| | - Wen Shan Yew
- Synthetic Biology Translational Research Programme, Yong Loo Lin School of Medicine, National University of Singapore, 14 Medical Drive, Singapore 117599, Singapore;
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, 8 Medical Drive, Singapore 117597, Singapore
| | - Hao Fan
- Bioinformatics Institute, A*STAR, 30 Biopolis Street, Matrix #07-01, Singapore 138671, Singapore; (R.K.V.); (Y.D.H.)
- Synthetic Biology Translational Research Programme, Yong Loo Lin School of Medicine, National University of Singapore, 14 Medical Drive, Singapore 117599, Singapore;
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164
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Biswas AD, Catte A, Mancini G, Barone V. Analysis of L-DOPA and droxidopa binding to human β 2-adrenergic receptor. Biophys J 2021; 120:5631-5643. [PMID: 34767786 PMCID: PMC8715240 DOI: 10.1016/j.bpj.2021.11.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 10/28/2021] [Accepted: 11/03/2021] [Indexed: 12/29/2022] Open
Abstract
Over the last two decades, an increasing number of studies has been devoted to a deeper understanding of the molecular process involved in the binding of various agonists and antagonists to active and inactive conformations of β2-adrenergic receptor (β2AR). The 3.2 Å x-ray crystal structure of human β2AR active state in combination with the endogenous low affinity agonist adrenaline offers an ideal starting structure for studying the binding of various catecholamines to adrenergic receptors. We show that molecular docking of levodopa (L-DOPA) and droxidopa into rigid and flexible β2AR models leads for both ligands to binding anchor sites comparable to those experimentally reported for adrenaline, namely D113/N312 and S203/S204/S207 side chains. Both ligands have a hydrogen bond network that is extremely similar to those of noradrenaline and dopamine. Interestingly, redocking neutral and protonated versions of adrenaline to rigid and flexible β2AR models results in binding poses that are more energetically stable and distinct from the x-ray crystal structure. Similarly, lowest energy conformations of noradrenaline and dopamine generated by docking into flexible β2AR models had binding free energies lower than those of best poses in rigid receptor models. Furthermore, our findings show that L-DOPA and droxidopa molecules have binding affinities comparable to those predicted for adrenaline, noradrenaline, and dopamine, which are consistent with previous experimental and computational findings and supported by the molecular dynamics simulations of β2AR-ligand complexes performed here.
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165
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Abrol R, Serrano E, Santiago LJ. Development of enhanced conformational sampling methods to probe the activation landscape of GPCRs. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2021; 128:325-359. [PMID: 35034722 DOI: 10.1016/bs.apcsb.2021.11.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/29/2023]
Abstract
G protein-coupled receptors (GPCRs) make up the largest superfamily of integral membrane proteins and play critical signal transduction roles in many physiological processes. Developments in molecular biology, biophysical, biochemical, pharmacological, and computational techniques aimed at these important therapeutic targets are beginning to provide unprecedented details on the structural as well as functional basis of their pleiotropic signaling mediated by G proteins, β arrestins, and other transducers. This pleiotropy presents a pharmacological challenge as the same ligand-receptor interaction can cause a therapeutic effect as well as an undesirable on-target side-effect through different downstream pathways. GPCRs don't function as simple binary on-off switches but as finely tuned shape-shifting machines described by conformational ensembles, where unique subsets of conformations may be responsible for specific signaling cascades. X-ray crystallography and more recently cryo-electron microscopy are providing snapshots of some of these functionally-important receptor conformations bound to ligands and/or transducers, which are being utilized by computational methods to describe the dynamic conformational energy landscape of GPCRs. In this chapter, we review the progress in computational conformational sampling methods based on molecular dynamics and discrete sampling approaches that have been successful in complementing biophysical and biochemical studies on these receptors in terms of their activation mechanisms, allosteric effects, actions of biased ligands, and effects of pathological mutations. Some of the sampled simulation time scales are beginning to approach receptor activation time scales. The list of conformational sampling methods and example uses discussed is not exhaustive but includes representative examples that have pushed the limits of classical molecular dynamics and discrete sampling methods to describe the activation energy landscape of GPCRs.
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Affiliation(s)
- Ravinder Abrol
- Department of Chemistry and Biochemistry, California State University, Northridge, CA, United States.
| | - Erik Serrano
- Department of Chemistry and Biochemistry, California State University, Northridge, CA, United States
| | - Luis Jaimes Santiago
- Department of Chemistry and Biochemistry, California State University, Northridge, CA, United States
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166
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Ballante F, Kooistra AJ, Kampen S, de Graaf C, Carlsson J. Structure-Based Virtual Screening for Ligands of G Protein-Coupled Receptors: What Can Molecular Docking Do for You? Pharmacol Rev 2021; 73:527-565. [PMID: 34907092 DOI: 10.1124/pharmrev.120.000246] [Citation(s) in RCA: 61] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
G protein-coupled receptors (GPCRs) constitute the largest family of membrane proteins in the human genome and are important therapeutic targets. During the last decade, the number of atomic-resolution structures of GPCRs has increased rapidly, providing insights into drug binding at the molecular level. These breakthroughs have created excitement regarding the potential of using structural information in ligand design and initiated a new era of rational drug discovery for GPCRs. The molecular docking method is now widely applied to model the three-dimensional structures of GPCR-ligand complexes and screen for chemical probes in large compound libraries. In this review article, we first summarize the current structural coverage of the GPCR superfamily and the understanding of receptor-ligand interactions at atomic resolution. We then present the general workflow of structure-based virtual screening and strategies to discover GPCR ligands in chemical libraries. We assess the state of the art of this research field by summarizing prospective applications of virtual screening based on experimental structures. Strategies to identify compounds with specific efficacy and selectivity profiles are discussed, illustrating the opportunities and limitations of the molecular docking method. Our overview shows that structure-based virtual screening can discover novel leads and will be essential in pursuing the next generation of GPCR drugs. SIGNIFICANCE STATEMENT: Extraordinary advances in the structural biology of G protein-coupled receptors have revealed the molecular details of ligand recognition by this large family of therapeutic targets, providing novel avenues for rational drug design. Structure-based docking is an efficient computational approach to identify novel chemical probes from large compound libraries, which has the potential to accelerate the development of drug candidates.
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Affiliation(s)
- Flavio Ballante
- Science for Life Laboratory, Department of Cell and Molecular Biology, Uppsala University, Uppsala, Sweden (F.B., S.K., J.C.); Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen, Denmark (A.J.K.); and Sosei Heptares, Steinmetz Building, Granta Park, Great Abington, Cambridge, United Kingdom (C.d.G.)
| | - Albert J Kooistra
- Science for Life Laboratory, Department of Cell and Molecular Biology, Uppsala University, Uppsala, Sweden (F.B., S.K., J.C.); Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen, Denmark (A.J.K.); and Sosei Heptares, Steinmetz Building, Granta Park, Great Abington, Cambridge, United Kingdom (C.d.G.)
| | - Stefanie Kampen
- Science for Life Laboratory, Department of Cell and Molecular Biology, Uppsala University, Uppsala, Sweden (F.B., S.K., J.C.); Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen, Denmark (A.J.K.); and Sosei Heptares, Steinmetz Building, Granta Park, Great Abington, Cambridge, United Kingdom (C.d.G.)
| | - Chris de Graaf
- Science for Life Laboratory, Department of Cell and Molecular Biology, Uppsala University, Uppsala, Sweden (F.B., S.K., J.C.); Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen, Denmark (A.J.K.); and Sosei Heptares, Steinmetz Building, Granta Park, Great Abington, Cambridge, United Kingdom (C.d.G.)
| | - Jens Carlsson
- Science for Life Laboratory, Department of Cell and Molecular Biology, Uppsala University, Uppsala, Sweden (F.B., S.K., J.C.); Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen, Denmark (A.J.K.); and Sosei Heptares, Steinmetz Building, Granta Park, Great Abington, Cambridge, United Kingdom (C.d.G.)
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167
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Identification and characterization of an atypical Gαs-biased β 2AR agonist that fails to evoke airway smooth muscle cell tachyphylaxis. Proc Natl Acad Sci U S A 2021; 118:2026668118. [PMID: 34857633 PMCID: PMC8670521 DOI: 10.1073/pnas.2026668118] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/18/2021] [Indexed: 12/23/2022] Open
Abstract
We sought β2AR agonists for treating obstructive lung diseases such as asthma, in which this receptor relaxes airway smooth muscle (ASM) cells and opens airways. Agonists favoring Gs coupling (leads to airway relaxation) compared with activating β-arrestin (limits effectiveness due to receptor desensitization) were pursued in a 40-million-compound screening library. Of several agonists identified, one was apparently biased away from β-arrestin. Agonist–receptor–G protein modeling revealed different receptor interactions compared with other agonists. The favorable effects of the apparent biasing with this agonist were demonstrated in a physiologic system (ASM relaxation). These studies point to a different structural class of β-agonists that might be used to treat obstructive lung diseases without the adverse effects associated with tachyphylaxis. G protein–coupled receptors display multifunctional signaling, offering the potential for agonist structures to promote conformational selectivity for biased outputs. For β2-adrenergic receptors (β2AR), unbiased agonists stabilize conformation(s) that evoke coupling to Gαs (cyclic adenosine monophosphate [cAMP] production/human airway smooth muscle [HASM] cell relaxation) and β-arrestin engagement, the latter acting to quench Gαs signaling, contributing to receptor desensitization/tachyphylaxis. We screened a 40-million-compound scaffold ranking library, revealing unanticipated agonists with dihydroimidazolyl-butyl-cyclic urea scaffolds. The S-stereoisomer of compound C1 shows no detectable β-arrestin engagement/signaling by four methods. However, C1-S retained Gαs signaling—a divergence of the outputs favorable for treating asthma. Functional studies with two models confirmed the biasing: β2AR-mediated cAMP signaling underwent desensitization to the unbiased agonist albuterol but not to C1-S, and desensitization of HASM cell relaxation was observed with albuterol but not with C1-S. These HASM results indicate biologically pertinent biasing of C1-S, in the context of the relevant physiologic response, in the human cell type of interest. Thus, C1-S was apparently strongly biased away from β-arrestin, in contrast to albuterol and C5-S. C1-S structural modeling and simulations revealed binding differences compared with unbiased epinephrine at transmembrane (TM) segments 3,5,6,7 and ECL2. C1-S (R2 = cyclohexane) was repositioned in the pocket such that it lost a TM6 interaction and gained a TM7 interaction compared with the analogous unbiased C5-S (R2 = benzene group), which appears to contribute to C1-S biasing away from β-arrestin. Thus, an agnostic large chemical-space library identified agonists with receptor interactions that resulted in relevant signal splitting of β2AR actions favorable for treating obstructive lung disease.
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168
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Schoof M, Wang L, Cogan JZ, Lawrence RE, Boone M, Wuerth JD, Frost A, Walter P. Viral evasion of the integrated stress response through antagonism of eIF2-P binding to eIF2B. Nat Commun 2021; 12:7103. [PMID: 34876554 PMCID: PMC8651678 DOI: 10.1038/s41467-021-26164-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Accepted: 09/17/2021] [Indexed: 01/07/2023] Open
Abstract
Viral infection triggers activation of the integrated stress response (ISR). In response to viral double-stranded RNA (dsRNA), RNA-activated protein kinase (PKR) phosphorylates the translation initiation factor eIF2, converting it from a translation initiator into a potent translation inhibitor and this restricts the synthesis of viral proteins. Phosphorylated eIF2 (eIF2-P) inhibits translation by binding to eIF2's dedicated, heterodecameric nucleotide exchange factor eIF2B and conformationally inactivating it. We show that the NSs protein of Sandfly Fever Sicilian virus (SFSV) allows the virus to evade the ISR. Mechanistically, NSs tightly binds to eIF2B (KD = 30 nM), blocks eIF2-P binding, and rescues eIF2B GEF activity. Cryo-EM structures demonstrate that SFSV NSs and eIF2-P directly compete, with the primary NSs contacts to eIF2Bα mediated by five 'aromatic fingers'. NSs binding preserves eIF2B activity by maintaining eIF2B's conformation in its active A-State.
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Affiliation(s)
- Michael Schoof
- Howard Hughes Medical Institute, University of California at San Francisco, San Francisco, CA, USA
- Department of Biochemistry and Biophysics, University of California at San Francisco, San Francisco, CA, USA
| | - Lan Wang
- Howard Hughes Medical Institute, University of California at San Francisco, San Francisco, CA, USA
- Department of Biochemistry and Biophysics, University of California at San Francisco, San Francisco, CA, USA
| | - J Zachery Cogan
- Howard Hughes Medical Institute, University of California at San Francisco, San Francisco, CA, USA
- Department of Biochemistry and Biophysics, University of California at San Francisco, San Francisco, CA, USA
| | - Rosalie E Lawrence
- Howard Hughes Medical Institute, University of California at San Francisco, San Francisco, CA, USA
- Department of Biochemistry and Biophysics, University of California at San Francisco, San Francisco, CA, USA
| | - Morgane Boone
- Howard Hughes Medical Institute, University of California at San Francisco, San Francisco, CA, USA
- Department of Biochemistry and Biophysics, University of California at San Francisco, San Francisco, CA, USA
| | | | - Adam Frost
- Department of Biochemistry and Biophysics, University of California at San Francisco, San Francisco, CA, USA
- Chan Zuckerberg Biohub, San Francisco, CA, USA
| | - Peter Walter
- Howard Hughes Medical Institute, University of California at San Francisco, San Francisco, CA, USA.
- Department of Biochemistry and Biophysics, University of California at San Francisco, San Francisco, CA, USA.
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169
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Smith SO. Deconstructing the transmembrane core of class A G protein-coupled receptors. Trends Biochem Sci 2021; 46:1017-1029. [PMID: 34538727 PMCID: PMC8595765 DOI: 10.1016/j.tibs.2021.08.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Revised: 08/19/2021] [Accepted: 08/23/2021] [Indexed: 01/14/2023]
Abstract
Class A G protein-coupled receptors have evolved to recognize ligands ranging from small-molecule odorants to proteins. Although they are among the most diverse membrane receptors in eukaryotic organisms, they possess a highly conserved core within their seven-transmembrane helix framework. The conservation of the transmembrane core has led to the idea of a common mechanism by which ligand binding is coupled to the outward rotation of helix H6, the hallmark of an active receptor. Nevertheless, there is still no consensus on the mechanism of coupling or on the roles of specific residues within the core. Recent insights from crystallography and NMR spectroscopy provide a way to decompose the core into its essential structural and functional elements that shed new light on this important region.
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Affiliation(s)
- Steven O Smith
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY 11794-5215, USA.
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170
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Casey AB, Mukherjee M, McGlynn RP, Cui M, Kohut SJ, Booth RG. A new class of serotonin 5-HT 2A /5-HT 2C receptor inverse agonists: Synthesis, molecular modeling, in vitro and in vivo pharmacology of novel 2-aminotetralins. Br J Pharmacol 2021; 179:2610-2630. [PMID: 34837227 DOI: 10.1111/bph.15756] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Revised: 10/27/2021] [Accepted: 10/29/2021] [Indexed: 11/28/2022] Open
Abstract
BACKGROUND AND PURPOSE The 5-HT receptor (5-HTR) subtypes 5-HT2A and 5-HT2C are important neurotherapeutic targets, though, obtaining selectivity over 5-HT2B and closely related histamine H1 Rs is challenging. Here, we delineated molecular determinants of selective binding to 5-HT2A and 5-HT2C Rs for novel 4-phenyl-2-dimethylaminotetralins (4-PATs). EXPERIMENTAL APPROACH We synthesized 42 novel 4-PATs with halogen or aryl moieties at the C(4)-phenyl meta position. Affinity, function, molecular modeling, and 5-HT2A R mutagenesis studies were undertaken to understand structure-activity relationships at 5-HT2 -type and H1 Rs. Lead 4-PAT-type selective 5-HT2A /5-HT2C R inverse agonists were compared to pimavanserin, a selective 5-HT2A /5-HT2C R inverse agonist approved to treat psychoses, in the mouse head twitch response, and locomotor activity assays, as models relevant to antipsychotic drug development. KEY RESULTS Most 4-PAT diastereomers in the (2S,4R)-configuration bound non-selectively to 5-HT2A , 5-HT2C, and H1 Rs, with >100-fold selectivity over 5-HT2B Rs, whereas, diastereomers in the (2R,4R)-configuration bound preferentially to 5-HT2A over 5-HT2C Rs and had >100-fold selectivity over 5-HT2B and H1 Rs. Results suggest that G2385.42 and V2355.39 in 5-HT2A Rs (conserved in 5-HT2C Rs) are important for high affinity binding, whereas, interactions with T1945.42 and W1584.56 determine H1 R affinity. The 4-PAT (2S,4R)-2k, a potent and selective 5-HT2A /5-HT2C R inverse agonist, had activity like pimavanserin in the mouse head-twitch response assay, but was distinct in not suppressing locomotor activity. CONCLUSIONS AND IMPLICATIONS We provide evidence that the novel 4-PAT chemotype can yield selective 5-HT2A /5-HT2C R inverse agonists for antipsychotic drug development by optimizing ligand-receptor interactions in transmembrane domain 5. We also show that chirality can be exploited to attain selectivity over H1 Rs which may circumvent sedative effects.
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Affiliation(s)
- Austen B Casey
- Center for Drug Discovery, Northeastern University, Boston, Massachusetts, United States.,Department of Pharmaceutical Sciences, Northeastern University, Boston, Massachusetts, United States.,Department of Chemistry & Chemical Biology, Northeastern University, Boston, Massachusetts, United States
| | - Munmun Mukherjee
- Center for Drug Discovery, Northeastern University, Boston, Massachusetts, United States.,Department of Pharmaceutical Sciences, Northeastern University, Boston, Massachusetts, United States.,Department of Chemistry & Chemical Biology, Northeastern University, Boston, Massachusetts, United States
| | - Ryan P McGlynn
- Center for Drug Discovery, Northeastern University, Boston, Massachusetts, United States.,Department of Pharmaceutical Sciences, Northeastern University, Boston, Massachusetts, United States.,Department of Chemistry & Chemical Biology, Northeastern University, Boston, Massachusetts, United States
| | - Meng Cui
- Center for Drug Discovery, Northeastern University, Boston, Massachusetts, United States.,Department of Pharmaceutical Sciences, Northeastern University, Boston, Massachusetts, United States
| | - Stephen J Kohut
- Center for Drug Discovery, Northeastern University, Boston, Massachusetts, United States.,Department of Pharmaceutical Sciences, Northeastern University, Boston, Massachusetts, United States.,Behavioral Neuroimaging Laboratory, McLean Hospital and Department of Psychiatry, Harvard Medical School, Belmont, Massachusetts, United States
| | - Raymond G Booth
- Center for Drug Discovery, Northeastern University, Boston, Massachusetts, United States.,Department of Pharmaceutical Sciences, Northeastern University, Boston, Massachusetts, United States.,Department of Chemistry & Chemical Biology, Northeastern University, Boston, Massachusetts, United States
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171
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Bloch JS, Mukherjee S, Kowal J, Filippova EV, Niederer M, Pardon E, Steyaert J, Kossiakoff AA, Locher KP. Development of a universal nanobody-binding Fab module for fiducial-assisted cryo-EM studies of membrane proteins. Proc Natl Acad Sci U S A 2021; 118:e2115435118. [PMID: 34782475 PMCID: PMC8617411 DOI: 10.1073/pnas.2115435118] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2021] [Accepted: 10/11/2021] [Indexed: 11/18/2022] Open
Abstract
With conformation-specific nanobodies being used for a wide range of structural, biochemical, and cell biological applications, there is a demand for antigen-binding fragments (Fabs) that specifically and tightly bind these nanobodies without disturbing the nanobody-target protein interaction. Here, we describe the development of a synthetic Fab (termed NabFab) that binds the scaffold of an alpaca-derived nanobody with picomolar affinity. We demonstrate that upon complementary-determining region grafting onto this parent nanobody scaffold, nanobodies recognizing diverse target proteins and derived from llama or camel can cross-react with NabFab without loss of affinity. Using NabFab as a fiducial and size enhancer (50 kDa), we determined the high-resolution cryogenic electron microscopy (cryo-EM) structures of nanobody-bound VcNorM and ScaDMT, both small membrane proteins of ∼50 kDa. Using an additional anti-Fab nanobody further facilitated reliable initial three-dimensional structure determination from small cryo-EM test datasets. Given that NabFab is of synthetic origin, is humanized, and can be conveniently expressed in Escherichia coli in large amounts, it may be useful not only for structural biology but also for biomedical applications.
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Affiliation(s)
- Joël S Bloch
- Institute of Molecular Biology and Biophysics, ETH Zürich, 8093 Zürich, Switzerland
| | - Somnath Mukherjee
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL 60637
| | - Julia Kowal
- Institute of Molecular Biology and Biophysics, ETH Zürich, 8093 Zürich, Switzerland
| | - Ekaterina V Filippova
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL 60637
| | - Martina Niederer
- Institute of Molecular Biology and Biophysics, ETH Zürich, 8093 Zürich, Switzerland
| | - Els Pardon
- Structural Biology Brussels, Vrije Universiteit Brussel, B-1050 Brussels, Belgium
| | - Jan Steyaert
- Structural Biology Brussels, Vrije Universiteit Brussel, B-1050 Brussels, Belgium
| | - Anthony A Kossiakoff
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL 60637;
- Institute for Biophysical Dynamics, University of Chicago, Chicago, IL 60637
| | - Kaspar P Locher
- Institute of Molecular Biology and Biophysics, ETH Zürich, 8093 Zürich, Switzerland;
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172
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Liu T, Ji RL, Tao YX. Naturally occurring mutations in G protein-coupled receptors associated with obesity and type 2 diabetes mellitus. Pharmacol Ther 2021; 234:108044. [PMID: 34822948 DOI: 10.1016/j.pharmthera.2021.108044] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 11/15/2021] [Accepted: 11/15/2021] [Indexed: 12/12/2022]
Abstract
G protein-coupled receptors (GPCRs) are the largest family of membrane receptors involved in the regulation of almost all known physiological processes. Dysfunctions of GPCR-mediated signaling have been shown to cause various diseases. The prevalence of obesity and type 2 diabetes mellitus (T2DM), two strongly associated disorders, is increasing worldwide, with tremendous economical and health burden. New safer and more efficacious drugs are required for successful weight reduction and T2DM treatment. Multiple GPCRs are involved in the regulation of energy and glucose homeostasis. Mutations in these GPCRs contribute to the development and progression of obesity and T2DM. Therefore, these receptors can be therapeutic targets for obesity and T2DM. Indeed some of these receptors, such as melanocortin-4 receptor and glucagon-like peptide 1 receptor, have provided important new drugs for treating obesity and T2DM. This review will focus on the naturally occurring mutations of several GPCRs associated with obesity and T2DM, especially incorporating recent large genomic data and insights from structure-function studies, providing leads for future investigations.
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Affiliation(s)
- Ting Liu
- Department of Anatomy, Physiology and Pharmacology, Auburn University College of Veterinary Medicine, Auburn, AL 36849, United States
| | - Ren-Lei Ji
- Department of Anatomy, Physiology and Pharmacology, Auburn University College of Veterinary Medicine, Auburn, AL 36849, United States
| | - Ya-Xiong Tao
- Department of Anatomy, Physiology and Pharmacology, Auburn University College of Veterinary Medicine, Auburn, AL 36849, United States.
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173
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Chen J, Liu J, Yuan Y, Chen X, Zhang F, Pu X. Molecular Mechanisms of Diverse Activation Stimulated by Different Biased Agonists for the β2-Adrenergic Receptor. J Chem Inf Model 2021; 62:5175-5192. [PMID: 34802238 DOI: 10.1021/acs.jcim.1c01016] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
β2AR is an important drug target protein involving many diseases. Biased drugs induce specific signaling and provide additional clinical utility to optimize β2AR-based therapies. However, the biased signaling mechanism has not been elucidated. Motivated by the issue, we chose four agonists with divergent bias (balanced agonist, G-protein-biased agonist, and β-arrestin-biased agonists) and utilized Gaussian accelerated molecular dynamics simulation coupled with a dynamic network to probe the molecular mechanisms of distinct biased activation induced by the structural differences between the four agonists. Our simulations reveal that the G-protein-biased agonist induces an open conformation with the outward shifts of TM6 and TM7 for the intracellular domain, which will be beneficial to couple G protein. In contrast, the β-arrestin-biased agonists regulate an occluded conformation with a slightly outward movement of TM6 and an inward shift of TM7, which should favor β-arrestin signaling. The balanced agonist does not induce an observable outward shift for TM6 but, along with a slight tilt for TM7, leads to an inactive-like conformation. In addition, our results reveal the first time that ICL3 presents specific conformations with different agonists. The G-protein-biased agonist drives ICL3 to open so that the G protein-binding pocket can be available, while the β-arrestin-biased agonists induce ICL3 to form a closed conformation with a stable local α-helix. MM/PBSA analysis further reveals that the hydroxyl groups in the resorcinol of the G-protein-biased agonist form strong interactions with Y5.38 and S5.42, thus preventing tilting of the TM5 extracellular end. The catechol of the balanced agonist and the β-arrestin-biased ones induces the rearrangement of two hydrophobic residues F6.52 and W6.48. However, different from the balanced agonist, the ethyl substituent of β-arrestin-biased agonists forms additional hydrophobic interactions with W6.48 and F6.51 after the rearrangement, which should contribute to the β-arrestin bias. The shortest pathway analysis further reveals that the three residues Y7.43, N7.45, and N7.49 are crucial for allosterically regulating G-protein-biased signaling, while the two residues W6.48 and F6.44 make an important contribution to regulate β-arrestin-biased signaling. For the balanced agonist NE, the allosteric regulation pathway simultaneously involves the residue associated with G-protein-biased signaling like S5.46 and the residues related to β-arrestin-biased signaling like W6.48 and F6.44, thus producing unbiased signaling. The observations could advance our understanding of the biased activation mechanism on class A GPCRs and provide a useful guideline for the design of biased drugs.
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Affiliation(s)
- Jianfang Chen
- College of Chemistry, Sichuan University, Chengdu 610064, China
| | - Jiangting Liu
- College of Chemistry, Sichuan University, Chengdu 610064, China
| | - Yuan Yuan
- College of Management, Southwest University for Nationalities, Chengdu 610041, China
| | - Xin Chen
- College of Chemistry, Sichuan University, Chengdu 610064, China
| | - Fuhui Zhang
- College of Chemistry, Sichuan University, Chengdu 610064, China
| | - Xuemei Pu
- College of Chemistry, Sichuan University, Chengdu 610064, China
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174
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Akkapeddi P, Teng KW, Koide S. Monobodies as tool biologics for accelerating target validation and druggable site discovery. RSC Med Chem 2021; 12:1839-1853. [PMID: 34820623 PMCID: PMC8597423 DOI: 10.1039/d1md00188d] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Accepted: 08/26/2021] [Indexed: 12/21/2022] Open
Abstract
Despite increased investment and technological advancement, new drug approvals have not proportionally increased. Low drug approval rates, particularly for new targets, are linked to insufficient target validation at early stages. Thus, there remains a strong need for effective target validation techniques. Here, we review the use of synthetic binding proteins as tools for drug target validation, with focus on the monobody platform among several advanced synthetic binding protein platforms. Monobodies with high affinity and high selectivity can be rapidly developed against challenging targets, such as KRAS mutants, using protein engineering technologies. They have strong tendency to bind to functional sites and thus serve as drug-like molecules, and they can serve as targeting ligands for constructing bio-PROTACs. Genetically encoded monobodies are effective "tool biologics" for validating intracellular targets. They promote crystallization and help reveal the atomic structures of the monobody-target interface, which can inform drug design. Using case studies, we illustrate the potential of the monobody technology in accelerating target validation and small-molecule drug discovery.
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Affiliation(s)
- Padma Akkapeddi
- Perlmutter Cancer Center, New York University Langone Medical Center New York NY USA
| | - Kai Wen Teng
- Perlmutter Cancer Center, New York University Langone Medical Center New York NY USA
| | - Shohei Koide
- Perlmutter Cancer Center, New York University Langone Medical Center New York NY USA
- Department of Biochemistry and Molecular Pharmacology, New York University School of Medicine New York NY USA
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175
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Novel GPR120 Agonists with Improved Pharmacokinetic Profiles for the Treatment of Type 2 Diabetes. Molecules 2021; 26:molecules26226907. [PMID: 34833999 PMCID: PMC8624523 DOI: 10.3390/molecules26226907] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Revised: 11/11/2021] [Accepted: 11/12/2021] [Indexed: 11/16/2022] Open
Abstract
GPR120 is a promising target for the treatment of type 2 diabetes (T2DM), which is activated by free fatty acids (FFAs) and stimulates the release of glucagon-like peptide-1(GLP-1). GLP-1, as an incretin, can enhance glucose-dependent secretion of insulin from pancreatic beta cells and reduce blood glucose. In this study, a series of novel GPR120 agonists were designed and synthesized to improve the stability and hydrophilicity of the phenylpropanoic acid GPR120 agonist TUG-891. Compound 11b showed excellent GPR120 agonistic activity and pharmacokinetic properties, and could reduce the blood glucose of normal mice in a dose-dependent manner. In addition, no hypoglycemic side effects were observed even at a dose of 100 mg/kg. Moreover, 11b showed good anti-hyperglycemic effects in diet-induced obese (DIO) mice. Molecular simulation illustrated that compound 11b could enter the active site of GPR120 and interact with ARG99. Taken together, the results indicate that compound 11b might be a promising drug candidate for the treatment of T2DM.
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176
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Zhang F, Chen X, Chen J, Xu Y, Li S, Guo Y, Pu X. Probing Allosteric Regulation Mechanism of W7.35 on Agonist-Induced Activity for μOR by Mutation Simulation. J Chem Inf Model 2021; 62:5120-5135. [PMID: 34779608 DOI: 10.1021/acs.jcim.1c00650] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The residue located at 15 positions before the most conserved residue in TM7 (7.35 of Ballesteros-Weinstein number) plays important roles in ligand binding and the receptor activity for class A GPCRs. Nevertheless, its regulation mechanism has not been clearly clarified in experiments, and some controversies also exist for its impact on μ-opioid receptors (μOR) bound by agonists. Thus, we chose the μ-opioid receptor (μOR) of class A GPCRs as a representative and utilized a microsecond accelerated molecular dynamics simulation (aMD) coupled with a protein structure network (PSN) to explore the effect of W3187.35 on its functional activity induced by the agonist endomorphin2 mainly by a comparison of the wild system and its W7.35A mutant. When endomorphin2 binds to the wild-type μOR, TM6 in μOR moves outward to form an open intracellular conformation that is beneficial to accommodating the β-arrestin transducer, rather than the G-protein transducer due to the clash with the α5 helix of G-protein, thus acting as a β-arrestin biased agonist. However, the W318A mutation induces the intracellular part of μOR to form a closed state, which disfavors coupling with either G-protein or β-arrestin. The allosteric pathway analysis further reveals that the binding of endomorphin2 to the wild-type μOR transmits more activation signals to the β-arrestin binding site while the W318A mutation induces more structural signals to transmit to common binding residues of the G protein and β-arrestin. More interestingly, the residue at the 7.35 position regulates the shortest allosteric pathway in indirect ways by influencing the interactions between other ligand-binding residues and endomorphin2. W2936.48 and F2896.44 are important for regulating the different activities of μOR induced either by the agonist or by the mutation. Y3367.53, F3438.50, and D3408.47 play crucial roles in activating the β-arrestin biased signal induced by the agonist endomorphin2, while L1583.43 and V2866.41 devote important contributions to the change in the activity of endomorphin2 from the β-arrestin biased agonist to the antagonist upon the W318A mutation.
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Affiliation(s)
- Fuhui Zhang
- College of Chemistry, Sichuan University, Chengdu 610064, China
| | - Xin Chen
- College of Chemistry, Sichuan University, Chengdu 610064, China
| | - Jianfang Chen
- College of Chemistry, Sichuan University, Chengdu 610064, China
| | - Yanjiani Xu
- College of Chemistry, Sichuan University, Chengdu 610064, China
| | - Shiqi Li
- College of Chemistry, Sichuan University, Chengdu 610064, China
| | - Yanzhi Guo
- College of Chemistry, Sichuan University, Chengdu 610064, China
| | - Xuemei Pu
- College of Chemistry, Sichuan University, Chengdu 610064, China
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177
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Michael E, Covic L, Kuliopulos A. Lipopeptide Pepducins as Therapeutic Agents. Methods Mol Biol 2021; 2383:307-333. [PMID: 34766299 DOI: 10.1007/978-1-0716-1752-6_21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/29/2023]
Abstract
Pepducins are lipidated peptides that target the intracellular loops of G protein-coupled receptors (GPCRs) in order to modulate transmembrane signaling to internally located effectors. With a wide array of potential activities ranging from partial, biased, or full agonism to antagonism, pepducins represent a versatile class of compounds that can be used to potentially treat diverse human diseases or be employed as novel tools to probe complex mechanisms of receptor activation and signaling in cells and in animals. Here, we describe a number of different pepducins including an advanced compound, PZ-128, that has successfully progressed through phase 2 clinical trials in cardiac patients demonstrating safety and efficacy in suppressing myonecrosis and arterial thrombosis.
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Affiliation(s)
- Emily Michael
- Center of Hemostasis and Thrombosis Research, Division of Hematology-Oncology, Department of Medicine, Tufts Medical Center, Tufts University School of Medicine, Boston, MA, USA
| | - Lidija Covic
- Center of Hemostasis and Thrombosis Research, Division of Hematology-Oncology, Department of Medicine, Tufts Medical Center, Tufts University School of Medicine, Boston, MA, USA
| | - Athan Kuliopulos
- Center of Hemostasis and Thrombosis Research, Division of Hematology-Oncology, Department of Medicine, Tufts Medical Center, Tufts University School of Medicine, Boston, MA, USA.
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178
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Jullié D, Valbret Z, Stoeber M. Optical tools to study the subcellular organization of GPCR neuromodulation. J Neurosci Methods 2021; 366:109408. [PMID: 34763022 DOI: 10.1016/j.jneumeth.2021.109408] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Revised: 10/11/2021] [Accepted: 11/03/2021] [Indexed: 12/29/2022]
Abstract
Modulation of neuronal circuit activity is key to information processing in the brain. G protein-coupled receptors (GPCRs), the targets of most neuromodulatory ligands, show extremely diverse expression patterns in neurons and receptors can be localized in various sub-neuronal membrane compartments. Upon activation, GPCRs promote signaling cascades that alter the level of second messengers, drive phosphorylation changes, modulate ion channel function, and influence gene expression, all of which critically impact neuron physiology. Because of its high degree of complexity, this form of interneuronal communication has remained challenging to integrate into our conceptual understanding of brain function. Recent technological advances in fluorescence microscopy and the development of optical biosensors now allow investigating neuromodulation with unprecedented resolution on the level of individual cells. In this review, we will highlight recent imaging techniques that enable determining the precise localization of GPCRs in neurons, with specific focus on the subcellular and nanoscale level. Downstream of receptors, we describe novel conformation-specific biosensors that allow for real-time monitoring of GPCR activation and of distinct signal transduction events in neurons. Applying these new tools has the potential to provide critical insights into the function and organization of GPCRs in neuronal cells and may help decipher the molecular and cellular mechanisms that underlie neuromodulation.
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Affiliation(s)
- Damien Jullié
- Department of Psychiatry, University of California San Francisco, San Francisco, USA.
| | - Zoé Valbret
- Department of Cell Physiology and Metabolism, University of Geneva, Geneva, Switzerland
| | - Miriam Stoeber
- Department of Cell Physiology and Metabolism, University of Geneva, Geneva, Switzerland.
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179
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Yokoi S, Mitsutake A. Characteristic structural difference between inactive and active states of orexin 2 receptor determined using molecular dynamics simulations. Biophys Rev 2021; 14:221-231. [DOI: 10.1007/s12551-021-00862-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Accepted: 10/20/2021] [Indexed: 12/12/2022] Open
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180
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Matsuzaki Y, Aoki W, Miyazaki T, Aburaya S, Ohtani Y, Kajiwara K, Koike N, Minakuchi H, Miura N, Kadonosono T, Ueda M. Peptide barcoding for one-pot evaluation of sequence-function relationships of nanobodies. Sci Rep 2021; 11:21516. [PMID: 34728738 PMCID: PMC8563947 DOI: 10.1038/s41598-021-01019-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2021] [Accepted: 10/21/2021] [Indexed: 11/17/2022] Open
Abstract
Optimisation of protein binders relies on laborious screening processes. Investigation of sequence–function relationships of protein binders is particularly slow, since mutants are purified and evaluated individually. Here we developed peptide barcoding, a high-throughput approach for accurate investigation of sequence–function relationships of hundreds of protein binders at once. Our approach is based on combining the generation of a mutagenised nanobody library fused with unique peptide barcodes, the formation of nanobody–antigen complexes at different ratios, their fine fractionation by size-exclusion chromatography and quantification of peptide barcodes by targeted proteomics. Applying peptide barcoding to an anti-GFP nanobody as a model, we successfully identified residues important for the binding affinity of anti-GFP nanobody at once. Peptide barcoding discriminated subtle changes in KD at the order of nM to sub-nM. Therefore, peptide barcoding is a powerful tool for engineering protein binders, enabling reliable one-pot evaluation of sequence–function relationships.
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Affiliation(s)
- Yusei Matsuzaki
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto, 606-8502, Japan
| | - Wataru Aoki
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto, 606-8502, Japan. .,Kyoto Integrated Science and Technology Bio-Analysis Center, Simogyo-ku, Kyoto, 600-8813, Japan. .,JST, CREST, Chiyoda-ku, Tokyo, 102-0076, Japan. .,JST, COI-NEXT, Chiyoda-ku, Tokyo, 102-0076, Japan. .,JST, FOREST, Chiyoda-ku, Tokyo, 102-0076, Japan.
| | - Takumi Miyazaki
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto, 606-8502, Japan
| | - Shunsuke Aburaya
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto, 606-8502, Japan
| | - Yuta Ohtani
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto, 606-8502, Japan
| | - Kaho Kajiwara
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto, 606-8502, Japan
| | - Naoki Koike
- TechnoPro, Inc. TechnoPro R&D, Company, Tokyo, 106-6135, Japan
| | | | - Natsuko Miura
- Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Naka-ku, Sakai, 599-8531, Japan
| | - Tetsuya Kadonosono
- School of Life Science and Technology, Tokyo Institute of Technology, Midori-ku, Yokohama, 226-8501, Japan
| | - Mitsuyoshi Ueda
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto, 606-8502, Japan.,Kyoto Integrated Science and Technology Bio-Analysis Center, Simogyo-ku, Kyoto, 600-8813, Japan.,JST, CREST, Chiyoda-ku, Tokyo, 102-0076, Japan.,JST, COI-NEXT, Chiyoda-ku, Tokyo, 102-0076, Japan
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181
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García-Nafría J, Tate CG. Structure determination of GPCRs: cryo-EM compared with X-ray crystallography. Biochem Soc Trans 2021; 49:2345-2355. [PMID: 34581758 PMCID: PMC8589417 DOI: 10.1042/bst20210431] [Citation(s) in RCA: 47] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Revised: 09/01/2021] [Accepted: 09/03/2021] [Indexed: 12/19/2022]
Abstract
G protein-coupled receptors (GPCRs) are the largest single family of cell surface receptors encoded by the human genome and they play pivotal roles in co-ordinating cellular systems throughout the human body, making them ideal drug targets. Structural biology has played a key role in defining how receptors are activated and signal through G proteins and β-arrestins. The application of structure-based drug design (SBDD) is now yielding novel compounds targeting GPCRs. There is thus significant interest from both academia and the pharmaceutical industry in the structural biology of GPCRs as currently only about one quarter of human non-odorant receptors have had their structure determined. Initially, all the structures were determined by X-ray crystallography, but recent advances in electron cryo-microscopy (cryo-EM) now make GPCRs tractable targets for single-particle cryo-EM with comparable resolution to X-ray crystallography. So far this year, 78% of the 99 GPCR structures deposited in the PDB (Jan-Jul 2021) were determined by cryo-EM. Cryo-EM has also opened up new possibilities in GPCR structural biology, such as determining structures of GPCRs embedded in a lipid nanodisc and multiple GPCR conformations from a single preparation. However, X-ray crystallography still has a number of advantages, particularly in the speed of determining many structures of the same receptor bound to different ligands, an essential prerequisite for effective SBDD. We will discuss the relative merits of cryo-EM and X-ray crystallography for the structure determination of GPCRs and the future potential of both techniques.
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Affiliation(s)
- Javier García-Nafría
- Institute for Biocomputation and Physics of Complex Systems (BIFI) and Laboratorio de Microscopías Avanzadas (LMA), University of Zaragoza, 50018 Zaragoza, Spain
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182
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Hauser AS, Kooistra AJ, Munk C, Heydenreich FM, Veprintsev DB, Bouvier M, Babu MM, Gloriam DE. GPCR activation mechanisms across classes and macro/microscales. Nat Struct Mol Biol 2021; 28:879-888. [PMID: 34759375 PMCID: PMC8580822 DOI: 10.1038/s41594-021-00674-7] [Citation(s) in RCA: 112] [Impact Index Per Article: 37.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Accepted: 09/22/2021] [Indexed: 12/27/2022]
Abstract
Two-thirds of human hormones and one-third of clinical drugs activate ~350 G-protein-coupled receptors (GPCR) belonging to four classes: A, B1, C and F. Whereas a model of activation has been described for class A, very little is known about the activation of the other classes, which differ by being activated by endogenous ligands bound mainly or entirely extracellularly. Here we show that, although they use the same structural scaffold and share several 'helix macroswitches', the GPCR classes differ in their 'residue microswitch' positions and contacts. We present molecular mechanistic maps of activation for each GPCR class and methods for contact analysis applicable for any functional determinants. This provides a superfamily residue-level rationale for conformational selection and allosteric communication by ligands and G proteins, laying the foundation for receptor-function studies and drugs with the desired modality.
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Affiliation(s)
- Alexander S Hauser
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen, Denmark
| | - Albert J Kooistra
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen, Denmark
| | - Christian Munk
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen, Denmark
- Data Tools Department, Novozymes A/S, Copenhagen, Denmark
| | - Franziska M Heydenreich
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA, USA
- Department of Biochemistry and Molecular Medicine, Institute for Research in Immunology and Cancer, Université de Montréal, Montreal, Quebec, Canada
- Laboratory of Molecular Biology, Cambridge Biomedical Campus, Cambridge, UK
| | - Dmitry B Veprintsev
- Centre of Membrane Proteins and Receptors (COMPARE), University of Nottingham, Nottingham, UK
- Division of Physiology, Pharmacology & Neuroscience, School of Life Sciences, University of Nottingham, Nottingham, UK
| | - Michel Bouvier
- Department of Biochemistry and Molecular Medicine, Institute for Research in Immunology and Cancer, Université de Montréal, Montreal, Quebec, Canada
| | - M Madan Babu
- Department of Structural Biology and Center for Data Driven Discovery, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - David E Gloriam
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen, Denmark.
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183
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Kricker JA, Page CP, Gardarsson FR, Baldursson O, Gudjonsson T, Parnham MJ. Nonantimicrobial Actions of Macrolides: Overview and Perspectives for Future Development. Pharmacol Rev 2021; 73:233-262. [PMID: 34716226 DOI: 10.1124/pharmrev.121.000300] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Macrolides are among the most widely prescribed broad spectrum antibacterials, particularly for respiratory infections. It is now recognized that these drugs, in particular azithromycin, also exert time-dependent immunomodulatory actions that contribute to their therapeutic benefit in both infectious and other chronic inflammatory diseases. Their increased chronic use in airway inflammation and, more recently, of azithromycin in COVID-19, however, has led to a rise in bacterial resistance. An additional crucial aspect of chronic airway inflammation, such as chronic obstructive pulmonary disease, as well as other inflammatory disorders, is the loss of epithelial barrier protection against pathogens and pollutants. In recent years, azithromycin has been shown with time to enhance the barrier properties of airway epithelial cells, an action that makes an important contribution to its therapeutic efficacy. In this article, we review the background and evidence for various immunomodulatory and time-dependent actions of macrolides on inflammatory processes and on the epithelium and highlight novel nonantibacterial macrolides that are being studied for immunomodulatory and barrier-strengthening properties to circumvent the risk of bacterial resistance that occurs with macrolide antibacterials. We also briefly review the clinical effects of macrolides in respiratory and other inflammatory diseases associated with epithelial injury and propose that the beneficial epithelial effects of nonantibacterial azithromycin derivatives in chronic inflammation, even given prophylactically, are likely to gain increasing attention in the future. SIGNIFICANCE STATEMENT: Based on its immunomodulatory properties and ability to enhance the protective role of the lung epithelium against pathogens, azithromycin has proven superior to other macrolides in treating chronic respiratory inflammation. A nonantibiotic azithromycin derivative is likely to offer prophylactic benefits against inflammation and epithelial damage of differing causes while preserving the use of macrolides as antibiotics.
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Affiliation(s)
- Jennifer A Kricker
- EpiEndo Pharmaceuticals, Reykjavik, Iceland (J.A.K., C.P.P., F.R.G., O.B., T.G., M.J.P.); Stem Cell Research Unit, Biomedical Center, University of Iceland, Reykjavik, Iceland (J.A.K., T.G.); Sackler Institute of Pulmonary Pharmacology, Institute of Pharmaceutical Science, King's College London, London, United Kingdom (C.P.P.); Department of Respiratory Medicine (O.B.), Department of Laboratory Hematology (T.G.), Landspitali-University Hospital, Reykjavik, Iceland; Faculty of Biochemistry, Chemistry and Pharmacy, JW Goethe University Frankfurt am Main, Germany (M.J.P.)
| | - Clive P Page
- EpiEndo Pharmaceuticals, Reykjavik, Iceland (J.A.K., C.P.P., F.R.G., O.B., T.G., M.J.P.); Stem Cell Research Unit, Biomedical Center, University of Iceland, Reykjavik, Iceland (J.A.K., T.G.); Sackler Institute of Pulmonary Pharmacology, Institute of Pharmaceutical Science, King's College London, London, United Kingdom (C.P.P.); Department of Respiratory Medicine (O.B.), Department of Laboratory Hematology (T.G.), Landspitali-University Hospital, Reykjavik, Iceland; Faculty of Biochemistry, Chemistry and Pharmacy, JW Goethe University Frankfurt am Main, Germany (M.J.P.)
| | - Fridrik Runar Gardarsson
- EpiEndo Pharmaceuticals, Reykjavik, Iceland (J.A.K., C.P.P., F.R.G., O.B., T.G., M.J.P.); Stem Cell Research Unit, Biomedical Center, University of Iceland, Reykjavik, Iceland (J.A.K., T.G.); Sackler Institute of Pulmonary Pharmacology, Institute of Pharmaceutical Science, King's College London, London, United Kingdom (C.P.P.); Department of Respiratory Medicine (O.B.), Department of Laboratory Hematology (T.G.), Landspitali-University Hospital, Reykjavik, Iceland; Faculty of Biochemistry, Chemistry and Pharmacy, JW Goethe University Frankfurt am Main, Germany (M.J.P.)
| | - Olafur Baldursson
- EpiEndo Pharmaceuticals, Reykjavik, Iceland (J.A.K., C.P.P., F.R.G., O.B., T.G., M.J.P.); Stem Cell Research Unit, Biomedical Center, University of Iceland, Reykjavik, Iceland (J.A.K., T.G.); Sackler Institute of Pulmonary Pharmacology, Institute of Pharmaceutical Science, King's College London, London, United Kingdom (C.P.P.); Department of Respiratory Medicine (O.B.), Department of Laboratory Hematology (T.G.), Landspitali-University Hospital, Reykjavik, Iceland; Faculty of Biochemistry, Chemistry and Pharmacy, JW Goethe University Frankfurt am Main, Germany (M.J.P.)
| | - Thorarinn Gudjonsson
- EpiEndo Pharmaceuticals, Reykjavik, Iceland (J.A.K., C.P.P., F.R.G., O.B., T.G., M.J.P.); Stem Cell Research Unit, Biomedical Center, University of Iceland, Reykjavik, Iceland (J.A.K., T.G.); Sackler Institute of Pulmonary Pharmacology, Institute of Pharmaceutical Science, King's College London, London, United Kingdom (C.P.P.); Department of Respiratory Medicine (O.B.), Department of Laboratory Hematology (T.G.), Landspitali-University Hospital, Reykjavik, Iceland; Faculty of Biochemistry, Chemistry and Pharmacy, JW Goethe University Frankfurt am Main, Germany (M.J.P.)
| | - Michael J Parnham
- EpiEndo Pharmaceuticals, Reykjavik, Iceland (J.A.K., C.P.P., F.R.G., O.B., T.G., M.J.P.); Stem Cell Research Unit, Biomedical Center, University of Iceland, Reykjavik, Iceland (J.A.K., T.G.); Sackler Institute of Pulmonary Pharmacology, Institute of Pharmaceutical Science, King's College London, London, United Kingdom (C.P.P.); Department of Respiratory Medicine (O.B.), Department of Laboratory Hematology (T.G.), Landspitali-University Hospital, Reykjavik, Iceland; Faculty of Biochemistry, Chemistry and Pharmacy, JW Goethe University Frankfurt am Main, Germany (M.J.P.)
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184
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Mahmood MI, Yamashita T. Influence of Lipid Bilayer on the GPCR Structure: Comparison of All-Atom Lipid Force Fields. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2021. [DOI: 10.1246/bcsj.20210244] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Md. Iqbal Mahmood
- Laboratory for Systems Biology and Medicine, Research Center for Advanced Science and Technology, the University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8904, Japan
| | - Takefumi Yamashita
- Laboratory for Systems Biology and Medicine, Research Center for Advanced Science and Technology, the University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8904, Japan
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185
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Vidad AR, Macaspac S, Ng HL. Locating ligand binding sites in G-protein coupled receptors using combined information from docking and sequence conservation. PeerJ 2021; 9:e12219. [PMID: 34631323 PMCID: PMC8475542 DOI: 10.7717/peerj.12219] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Accepted: 09/06/2021] [Indexed: 11/20/2022] Open
Abstract
GPCRs (G-protein coupled receptors) are the largest family of drug targets and share a conserved structure. Binding sites are unknown for many important GPCR ligands due to the difficulties of GPCR recombinant expression, biochemistry, and crystallography. We describe our approach, ConDockSite, for predicting ligand binding sites in class A GPCRs using combined information from surface conservation and docking, starting from crystal structures or homology models. We demonstrate the effectiveness of ConDockSite on crystallized class A GPCRs such as the beta2 adrenergic and A2A adenosine receptors. We also demonstrate that ConDockSite successfully predicts ligand binding sites from high-quality homology models. Finally, we apply ConDockSite to predict the ligand binding sites on a structurally uncharacterized GPCR, GPER, the G-protein coupled estrogen receptor. Most of the sites predicted by ConDockSite match those found in other independent modeling studies. ConDockSite predicts that four ligands bind to a common location on GPER at a site deep in the receptor cleft. Incorporating sequence conservation information in ConDockSite overcomes errors introduced from physics-based scoring functions and homology modeling.
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Affiliation(s)
- Ashley Ryan Vidad
- Department of Chemistry, University of Hawaii at Manoa, Honolulu, Hawaii, United States of America
| | - Stephen Macaspac
- Department of Chemistry, University of Hawaii at Manoa, Honolulu, Hawaii, United States of America
| | - Ho Leung Ng
- Department of Biochemistry and Molecular Biophysics, Kansas State University, Manhattan, Kansas, United States of America
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186
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Hegron A, Huh E, Deupi X, Sokrat B, Gao W, Le Gouill C, Canouil M, Boissel M, Charpentier G, Roussel R, Balkau B, Froguel P, Plouffe B, Bonnefond A, Lichtarge O, Jockers R, Bouvier M. Identification of Key Regions Mediating Human Melatonin Type 1 Receptor Functional Selectivity Revealed by Natural Variants. ACS Pharmacol Transl Sci 2021; 4:1614-1627. [PMID: 34661078 PMCID: PMC8507577 DOI: 10.1021/acsptsci.1c00157] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Indexed: 11/30/2022]
Abstract
Melatonin is a hormone mainly produced by the pineal gland and MT1 is one of the two G protein-coupled receptors (GPCRs) mediating its action. Despite an increasing number of available GPCR crystal structures, the molecular mechanism of activation of a large number of receptors, including MT1, remains poorly understood. The purpose of this study is to elucidate the structural elements involved in the process of MT1's activation using naturally occurring variants affecting its function. Thirty-six nonsynonymous variants, including 34 rare ones, were identified in MTNR1A (encoding MT1) from a cohort of 8687 individuals and their signaling profiles were characterized using Bioluminescence Resonance Energy Transfer-based sensors probing 11 different signaling pathways. Computational analysis of the experimental data allowed us to group the variants in clusters according to their signaling profiles and to analyze the position of each variant in the context of the three-dimensional structure of MT1 to link functional selectivity to structure. MT1 variant signaling profiles revealed three clusters characterized by (1) wild-type-like variants, (2) variants with selective defect of βarrestin-2 recruitment, and (3) severely defective variants on all pathways. Our structural analysis allows us to identify important regions for βarrestin-2 recruitment as well as for Gα12 and Gα15 activation. In addition to identifying MT1 domains differentially controlling the activation of the various signaling effectors, this study illustrates how natural variants can be used as tools to study the molecular mechanisms of receptor activation.
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Affiliation(s)
- Alan Hegron
- Université
de Paris, Institut Cochin, CNRS, INSERM, F-75014 Paris, France
- Department
of Biochemistry and Molecular Medicine, University de Montréal, Montreal, Quebec, H3T 1J4 Canada
- Institute
for Research in Immunology and Cancer, University
of Montreal, Montreal, Quebec, H3T 1J4 Canada
| | - Eunna Huh
- Department
of Pharmacology and Chemical Biology, Baylor
College of Medicine, Houston, Texas 77030, United States of America
| | - Xavier Deupi
- Laboratory
of Biomolecular Research, Paul Scherrer
Institute (PSI), 5232 Villigen, Switzerland
- Condensed
Matter Theory group, Paul Scherrer Institute
(PSI), 5232 Villigen, Switzerland
| | - Badr Sokrat
- Department
of Biochemistry and Molecular Medicine, University de Montréal, Montreal, Quebec, H3T 1J4 Canada
- Institute
for Research in Immunology and Cancer, University
of Montreal, Montreal, Quebec, H3T 1J4 Canada
| | - Wenwen Gao
- Université
de Paris, Institut Cochin, CNRS, INSERM, F-75014 Paris, France
| | - Christian Le Gouill
- Institute
for Research in Immunology and Cancer, University
of Montreal, Montreal, Quebec, H3T 1J4 Canada
| | - Mickaël Canouil
- Inserm
UMR1283, CNRS UMR8199, European Genomic Institute for Diabetes (EGID), Institut Pasteur de Lille, Lille, 59000, France
- University
of Lille, Lille University
Hospital, Lille, 59000, France
| | - Mathilde Boissel
- Inserm
UMR1283, CNRS UMR8199, European Genomic Institute for Diabetes (EGID), Institut Pasteur de Lille, Lille, 59000, France
- University
of Lille, Lille University
Hospital, Lille, 59000, France
| | - Guillaume Charpentier
- Centre d’Étude et de Recherche pour l’Intensification
du Traitement du Diabète, 91000, Evry, France
| | - Ronan Roussel
- Department
of Diabetology Endocrinology Nutrition, Hôpital Bichat, DHU FIRE, Assistance Publique Hôpitaux
de Paris, 75004 Paris, France
- Inserm U1138, Centre de Recherche des Cordeliers, 75006 Paris, France
- UFR de Médecine, University Paris
Diderot, Sorbonne Paris Cité, 75006 Paris, France
| | - Beverley Balkau
- Inserm U1018, Center for Research in Epidemiology and Population
Health, 94805 Villejuif, France
- University
Paris-Saclay, University Paris-Sud, 94270 Villejuif, France
| | - Philippe Froguel
- Inserm
UMR1283, CNRS UMR8199, European Genomic Institute for Diabetes (EGID), Institut Pasteur de Lille, Lille, 59000, France
- University
of Lille, Lille University
Hospital, Lille, 59000, France
- Department
of Metabolism, Imperial College London, London, W12 0NN, United Kingdom
| | - Bianca Plouffe
- Department
of Biochemistry and Molecular Medicine, University de Montréal, Montreal, Quebec, H3T 1J4 Canada
- Institute
for Research in Immunology and Cancer, University
of Montreal, Montreal, Quebec, H3T 1J4 Canada
| | - Amélie Bonnefond
- Inserm
UMR1283, CNRS UMR8199, European Genomic Institute for Diabetes (EGID), Institut Pasteur de Lille, Lille, 59000, France
- University
of Lille, Lille University
Hospital, Lille, 59000, France
- Department
of Metabolism, Imperial College London, London, W12 0NN, United Kingdom
| | - Olivier Lichtarge
- Department
of Pharmacology and Chemical Biology, Baylor
College of Medicine, Houston, Texas 77030, United States of America
- Department
of Molecular and Human Genetics, Baylor
College of Medicine, Houston, Texas 77030, United States
| | - Ralf Jockers
- Université
de Paris, Institut Cochin, CNRS, INSERM, F-75014 Paris, France
| | - Michel Bouvier
- Department
of Biochemistry and Molecular Medicine, University de Montréal, Montreal, Quebec, H3T 1J4 Canada
- Institute
for Research in Immunology and Cancer, University
of Montreal, Montreal, Quebec, H3T 1J4 Canada
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187
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De Bruyn P, Prolič-Kalinšek M, Vandervelde A, Malfait M, Sterckx YGJ, Sobott F, Hadži S, Pardon E, Steyaert J, Loris R. Nanobody-aided crystallization of the transcription regulator PaaR2 from Escherichia coli O157:H7. Acta Crystallogr F Struct Biol Commun 2021; 77:374-384. [PMID: 34605442 PMCID: PMC8488858 DOI: 10.1107/s2053230x21009006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2021] [Accepted: 08/30/2021] [Indexed: 11/10/2022] Open
Abstract
paaR2-paaA2-parE2 is a three-component toxin-antitoxin module found in prophage CP-993P of Escherichia coli O157:H7. Transcription regulation of this module occurs via the 123-amino-acid regulator PaaR2, which forms a large oligomeric structure. Despite appearing to be well folded, PaaR2 withstands crystallization, as does its N-terminal DNA-binding domain. Native mass spectrometry was used to screen for nanobodies that form a unique complex and stabilize the octameric structure of PaaR2. One such nanobody, Nb33, allowed crystallization of the protein. The resulting crystals belong to space group F432, with unit-cell parameter a = 317 Å, diffract to 4.0 Å resolution and are likely to contain four PaaR2 monomers and four nanobody monomers in the asymmetric unit. Crystals of two truncates containing the N-terminal helix-turn-helix domain also interact with Nb33, and the corresponding co-crystals diffracted to 1.6 and 1.75 Å resolution.
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Affiliation(s)
- Pieter De Bruyn
- Structural Biology Brussels, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium
- Center for Structural Biology, VIB, Pleinlaan 2, 1050 Brussels, Belgium
| | - Maruša Prolič-Kalinšek
- Structural Biology Brussels, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium
- Center for Structural Biology, VIB, Pleinlaan 2, 1050 Brussels, Belgium
| | - Alexandra Vandervelde
- Structural Biology Brussels, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium
- Center for Structural Biology, VIB, Pleinlaan 2, 1050 Brussels, Belgium
| | - Milan Malfait
- Structural Biology Brussels, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium
| | - Yann G.-J. Sterckx
- Structural Biology Brussels, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium
- Center for Structural Biology, VIB, Pleinlaan 2, 1050 Brussels, Belgium
- Laboratory of Medical Biochemistry (LMB) and the Infla-Med Centre of Excellence, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium
| | - Frank Sobott
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT, United Kingdom
- School of Molecular and Cellular Biology, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - San Hadži
- Department of Physical Chemistry, Faculty of Chemistry and Chemical Technology, University of Ljubljana, Večna pot 113, 1000 Ljubljana, Slovenia
| | - Els Pardon
- Structural Biology Brussels, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium
- Center for Structural Biology, VIB, Pleinlaan 2, 1050 Brussels, Belgium
| | - Jan Steyaert
- Structural Biology Brussels, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium
- Center for Structural Biology, VIB, Pleinlaan 2, 1050 Brussels, Belgium
| | - Remy Loris
- Structural Biology Brussels, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium
- Center for Structural Biology, VIB, Pleinlaan 2, 1050 Brussels, Belgium
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188
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Pani B, Ahn S, Rambarat PK, Vege S, Kahsai AW, Liu A, Valan BN, Staus DP, Costa T, Lefkowitz RJ. Unique Positive Cooperativity Between the β-Arrestin-Biased β-Blocker Carvedilol and a Small Molecule Positive Allosteric Modulator of the β2-Adrenergic Receptor. Mol Pharmacol 2021; 100:513-525. [PMID: 34580163 PMCID: PMC8998675 DOI: 10.1124/molpharm.121.000363] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Accepted: 08/30/2021] [Indexed: 01/08/2023] Open
Abstract
Among β-blockers that are clinically prescribed for heart failure, carvedilol is a first-choice agent with unique pharmacological properties. Carvedilol is distinct from other β-blockers in its ability to elicit β-arrestin–biased agonism, which has been suggested to underlie its cardioprotective effects. Augmenting the pharmacologic properties of carvedilol thus holds the promise of developing more efficacious and/or biased β-blockers. We recently identified compound-6 (cmpd-6), the first small molecule positive allosteric modulator of the β2-adrenergic receptor (β2AR). Cmpd-6 is positively cooperative with orthosteric agonists at the β2AR and enhances agonist-mediated transducer (G-protein and β-arrestin) signaling in an unbiased manner. Here, we report that cmpd-6, quite unexpectedly, displays strong positive cooperativity only with carvedilol among a panel of structurally diverse β-blockers. Cmpd-6 enhances the binding affinity of carvedilol for the β2AR and augments its ability to competitively antagonize agonist-induced cAMP generation. Cmpd-6 potentiates β-arrestin1– but not Gs-protein–mediated high-affinity binding of carvedilol at the β2AR and β-arrestin–mediated cellular functions in response to carvedilol including extracellular signal-regulated kinase phosphorylation, receptor endocytosis, and trafficking into lysosomes. Importantly, an analog of cmpd-6 that selectively retains positive cooperativity with carvedilol acts as a negative modulator of agonist-stimulated β2AR signaling. These unprecedented cooperative properties of carvedilol and cmpd-6 have implications for fundamental understanding of G-protein–coupled receptor (GPCR) allosteric modulation, as well as for the development of more effective biased beta blockers and other GPCR therapeutics.
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Affiliation(s)
- Biswaranjan Pani
- Department of Medicine (B.P., S.A., S.V., A.W.K., A.L., B.N.V., D.P.S., R.J.L.), Department of Biochemistry (R.J.L.), and Howard Hughes Medical Institute (R.J.L.), Duke University Medical Center, Durham, North Carolina, USA; Department of Medicine, Massachusetts General Hospital, Boston, Massachusetts, USA (P.K.R.); and Viale America 111, Rome, Italy (T.C.)
| | - Seungkirl Ahn
- Department of Medicine (B.P., S.A., S.V., A.W.K., A.L., B.N.V., D.P.S., R.J.L.), Department of Biochemistry (R.J.L.), and Howard Hughes Medical Institute (R.J.L.), Duke University Medical Center, Durham, North Carolina, USA; Department of Medicine, Massachusetts General Hospital, Boston, Massachusetts, USA (P.K.R.); and Viale America 111, Rome, Italy (T.C.)
| | - Paula K Rambarat
- Department of Medicine (B.P., S.A., S.V., A.W.K., A.L., B.N.V., D.P.S., R.J.L.), Department of Biochemistry (R.J.L.), and Howard Hughes Medical Institute (R.J.L.), Duke University Medical Center, Durham, North Carolina, USA; Department of Medicine, Massachusetts General Hospital, Boston, Massachusetts, USA (P.K.R.); and Viale America 111, Rome, Italy (T.C.)
| | - Shashank Vege
- Department of Medicine (B.P., S.A., S.V., A.W.K., A.L., B.N.V., D.P.S., R.J.L.), Department of Biochemistry (R.J.L.), and Howard Hughes Medical Institute (R.J.L.), Duke University Medical Center, Durham, North Carolina, USA; Department of Medicine, Massachusetts General Hospital, Boston, Massachusetts, USA (P.K.R.); and Viale America 111, Rome, Italy (T.C.)
| | - Alem W Kahsai
- Department of Medicine (B.P., S.A., S.V., A.W.K., A.L., B.N.V., D.P.S., R.J.L.), Department of Biochemistry (R.J.L.), and Howard Hughes Medical Institute (R.J.L.), Duke University Medical Center, Durham, North Carolina, USA; Department of Medicine, Massachusetts General Hospital, Boston, Massachusetts, USA (P.K.R.); and Viale America 111, Rome, Italy (T.C.)
| | - Andrew Liu
- Department of Medicine (B.P., S.A., S.V., A.W.K., A.L., B.N.V., D.P.S., R.J.L.), Department of Biochemistry (R.J.L.), and Howard Hughes Medical Institute (R.J.L.), Duke University Medical Center, Durham, North Carolina, USA; Department of Medicine, Massachusetts General Hospital, Boston, Massachusetts, USA (P.K.R.); and Viale America 111, Rome, Italy (T.C.)
| | - Bruno N Valan
- Department of Medicine (B.P., S.A., S.V., A.W.K., A.L., B.N.V., D.P.S., R.J.L.), Department of Biochemistry (R.J.L.), and Howard Hughes Medical Institute (R.J.L.), Duke University Medical Center, Durham, North Carolina, USA; Department of Medicine, Massachusetts General Hospital, Boston, Massachusetts, USA (P.K.R.); and Viale America 111, Rome, Italy (T.C.)
| | - Dean P Staus
- Department of Medicine (B.P., S.A., S.V., A.W.K., A.L., B.N.V., D.P.S., R.J.L.), Department of Biochemistry (R.J.L.), and Howard Hughes Medical Institute (R.J.L.), Duke University Medical Center, Durham, North Carolina, USA; Department of Medicine, Massachusetts General Hospital, Boston, Massachusetts, USA (P.K.R.); and Viale America 111, Rome, Italy (T.C.)
| | - Tommaso Costa
- Department of Medicine (B.P., S.A., S.V., A.W.K., A.L., B.N.V., D.P.S., R.J.L.), Department of Biochemistry (R.J.L.), and Howard Hughes Medical Institute (R.J.L.), Duke University Medical Center, Durham, North Carolina, USA; Department of Medicine, Massachusetts General Hospital, Boston, Massachusetts, USA (P.K.R.); and Viale America 111, Rome, Italy (T.C.)
| | - Robert J Lefkowitz
- Department of Medicine (B.P., S.A., S.V., A.W.K., A.L., B.N.V., D.P.S., R.J.L.), Department of Biochemistry (R.J.L.), and Howard Hughes Medical Institute (R.J.L.), Duke University Medical Center, Durham, North Carolina, USA; Department of Medicine, Massachusetts General Hospital, Boston, Massachusetts, USA (P.K.R.); and Viale America 111, Rome, Italy (T.C.)
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189
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Mitra A, Sarkar A, Borics A. Universal Properties and Specificities of the β 2-Adrenergic Receptor-G s Protein Complex Activation Mechanism Revealed by All-Atom Molecular Dynamics Simulations. Int J Mol Sci 2021; 22:10423. [PMID: 34638767 PMCID: PMC8508748 DOI: 10.3390/ijms221910423] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 09/23/2021] [Accepted: 09/23/2021] [Indexed: 11/16/2022] Open
Abstract
G protein-coupled receptors (GPCRs) are transmembrane proteins of high pharmacological relevance. It has been proposed that their activity is linked to structurally distinct, dynamically interconverting functional states and the process of activation relies on an interconnecting network of conformational switches in the transmembrane domain. However, it is yet to be uncovered how ligands with different extents of functional effect exert their actions. According to our recent hypothesis, based on indirect observations and the literature data, the transmission of the external stimulus to the intracellular surface is accompanied by the shift of macroscopic polarization in the transmembrane domain, furnished by concerted movements of highly conserved polar motifs and the rearrangement of polar species. In this follow-up study, we have examined the β2-adrenergic receptor (β2AR) to see if our hypothesis drawn from an extensive study of the μ-opioid receptor (MOP) is fundamental and directly transferable to other class A GPCRs. We have found that there are some general similarities between the two receptors, in agreement with previous studies, and there are some receptor-specific differences that could be associated with different signaling pathways.
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Affiliation(s)
- Argha Mitra
- Laboratory of Chemical Biology, Institute of Biochemistry, Biological Research Centre, 62. Temesvári krt., H-6726 Szeged, Hungary; (A.M.); (A.S.)
- Theoretical Medicine Doctoral School, Faculty of Medicine, University of Szeged, 97. Tisza L. krt., H-6722 Szeged, Hungary
| | - Arijit Sarkar
- Laboratory of Chemical Biology, Institute of Biochemistry, Biological Research Centre, 62. Temesvári krt., H-6726 Szeged, Hungary; (A.M.); (A.S.)
- Theoretical Medicine Doctoral School, Faculty of Medicine, University of Szeged, 97. Tisza L. krt., H-6722 Szeged, Hungary
| | - Attila Borics
- Laboratory of Chemical Biology, Institute of Biochemistry, Biological Research Centre, 62. Temesvári krt., H-6726 Szeged, Hungary; (A.M.); (A.S.)
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190
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Functional Analysis of the GPI Transamidase Complex by Screening for Amino Acid Mutations in Each Subunit. Molecules 2021; 26:molecules26185462. [PMID: 34576938 PMCID: PMC8465894 DOI: 10.3390/molecules26185462] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Revised: 09/01/2021] [Accepted: 09/01/2021] [Indexed: 12/20/2022] Open
Abstract
Glycosylphosphatidylinositol (GPI) anchor modification is a posttranslational modification of proteins that has been conserved in eukaryotes. The biosynthesis and transfer of GPI to proteins are carried out in the endoplasmic reticulum. Attachment of GPI to proteins is mediated by the GPI-transamidase (GPI-TA) complex, which recognizes and cleaves the C-terminal GPI attachment signal of precursor proteins. Then, GPI is transferred to the newly exposed C-terminus of the proteins. GPI-TA consists of five subunits: PIGK, GPAA1, PIGT, PIGS, and PIGU, and the absence of any subunit leads to the loss of activity. Here, we analyzed functionally important residues of the five subunits of GPI-TA by comparing conserved sequences among homologous proteins. In addition, we optimized the purification method for analyzing the structure of GPI-TA. Using purified GPI-TA, preliminary single particle images were obtained. Our results provide guidance for the structural and functional analysis of GPI-TA.
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191
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Baba S, Matsuura H, Kawamura T, Sakai N, Nakamura Y, Kawano Y, Mizuno N, Kumasaka T, Yamamoto M, Hirata K. Guidelines for de novo phasing using multiple small-wedge data collection. JOURNAL OF SYNCHROTRON RADIATION 2021; 28:1284-1295. [PMID: 34475278 PMCID: PMC8415328 DOI: 10.1107/s1600577521008067] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Accepted: 08/05/2021] [Indexed: 05/30/2023]
Abstract
Intense micro-focus X-ray beamlines available at synchrotron facilities have achieved high-quality data collection even from the microcrystals of membrane proteins. The automatic data collection system developed at SPring-8, named ZOO, has contributed to many structure determinations of membrane proteins using small-wedge synchrotron crystallography (SWSX) datasets. The `small-wedge' (5-20°) datasets are collected from multiple crystals and then merged to obtain the final structure factors. To our knowledge, no systematic investigation on the dose dependence of data accuracy has so far been reported for SWSX, which is between `serial crystallography' and `rotation crystallography'. Thus, herein, we investigated the optimal dose conditions for experimental phasing with SWSX. Phase determination using anomalous scattering signals was found to be more difficult at higher doses. Furthermore, merging more homogeneous datasets grouped by hierarchical clustering with controlled doses mildly reduced the negative factors in data collection, such as `lack of signal' and `radiation damage'. In turn, as more datasets were merged, more probable phases could be obtained across a wider range of doses. Therefore, our findings show that it is essential to choose a lower dose than 10 MGy for de novo structure determination by SWSX. In particular, data collection using a dose of 5 MGy proved to be optimal in balancing the amount of signal available while reducing the amount of damage as much as possible.
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Affiliation(s)
- Seiki Baba
- Protein Crystal Analysis Division, Japan Synchrotron Radiation Research Institute, 1-1-1 Kouto, Sayo, Hyogo 679-5198, Japan
| | - Hiroaki Matsuura
- Life Science Research Infrastructure Group, RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo-Cho, Sayo-gun, Hyogo 679-5148, Japan
| | - Takashi Kawamura
- Protein Crystal Analysis Division, Japan Synchrotron Radiation Research Institute, 1-1-1 Kouto, Sayo, Hyogo 679-5198, Japan
| | - Naoki Sakai
- Life Science Research Infrastructure Group, RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo-Cho, Sayo-gun, Hyogo 679-5148, Japan
| | - Yuki Nakamura
- Protein Crystal Analysis Division, Japan Synchrotron Radiation Research Institute, 1-1-1 Kouto, Sayo, Hyogo 679-5198, Japan
| | - Yoshiaki Kawano
- Life Science Research Infrastructure Group, RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo-Cho, Sayo-gun, Hyogo 679-5148, Japan
| | - Nobuhiro Mizuno
- Protein Crystal Analysis Division, Japan Synchrotron Radiation Research Institute, 1-1-1 Kouto, Sayo, Hyogo 679-5198, Japan
| | - Takashi Kumasaka
- Protein Crystal Analysis Division, Japan Synchrotron Radiation Research Institute, 1-1-1 Kouto, Sayo, Hyogo 679-5198, Japan
| | - Masaki Yamamoto
- Life Science Research Infrastructure Group, RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo-Cho, Sayo-gun, Hyogo 679-5148, Japan
| | - Kunio Hirata
- Life Science Research Infrastructure Group, RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo-Cho, Sayo-gun, Hyogo 679-5148, Japan
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192
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Yang F, Ling S, Zhou Y, Zhang Y, Lv P, Liu S, Fang W, Sun W, Hu LA, Zhang L, Shi P, Tian C. Different conformational responses of the β 2-adrenergic receptor-Gs complex upon binding of the partial agonist salbutamol or the full agonist isoprenaline. Natl Sci Rev 2021; 8:nwaa284. [PMID: 39040950 PMCID: PMC11261663 DOI: 10.1093/nsr/nwaa284] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Revised: 10/20/2020] [Accepted: 11/13/2020] [Indexed: 07/24/2024] Open
Abstract
G protein-coupled receptors (GPCRs) are responsible for most cytoplasmic signaling in response to extracellular ligands with different efficacy profiles. Various spectroscopic techniques have identified that agonists exhibiting varying efficacies can selectively stabilize a specific conformation of the receptor. However, the structural basis for activation of the GPCR-G protein complex by ligands with different efficacies is incompletely understood. To better understand the structural basis underlying the mechanisms by which ligands with varying efficacies differentially regulate the conformations of receptors and G proteins, we determined the structures of β2AR-Gαs[Formula: see text]γ bound with partial agonist salbutamol or bound with full agonist isoprenaline using single-particle cryo-electron microscopy at resolutions of 3.26 Å and 3.80 Å, respectively. Structural comparisons between the β2AR-Gs-salbutamol and β2AR-Gs-isoprenaline complexes demonstrated that the decreased binding affinity and efficacy of salbutamol compared with those of isoprenaline might be attributed to weakened hydrogen bonding interactions, attenuated hydrophobic interactions in the orthosteric binding pocket and different conformational changes in the rotamer toggle switch in TM6. Moreover, the observed stronger interactions between the intracellular loop 2 or 3 (ICL2 or ICL3) of β2AR and Gαs with binding of salbutamol versus isoprenaline might decrease phosphorylation in the salbutamol-activated β2AR-Gs complex. From the observed structural differences between these complexes of β2AR, a mechanism of β2AR activation by partial and full agonists is proposed to provide structural insights into β2AR desensitization.
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Affiliation(s)
- Fan Yang
- Hefei National Laboratory of Physical Sciences at Microscale and School of Life Sciences, University of Science and Technology of China, Hefei 230026, China
| | - Shenglong Ling
- Hefei National Laboratory of Physical Sciences at Microscale and School of Life Sciences, University of Science and Technology of China, Hefei 230026, China
| | - Yingxin Zhou
- Hefei National Laboratory of Physical Sciences at Microscale and School of Life Sciences, University of Science and Technology of China, Hefei 230026, China
| | - Yanan Zhang
- Hefei National Laboratory of Physical Sciences at Microscale and School of Life Sciences, University of Science and Technology of China, Hefei 230026, China
| | - Pei Lv
- Hefei National Laboratory of Physical Sciences at Microscale and School of Life Sciences, University of Science and Technology of China, Hefei 230026, China
| | - Sanling Liu
- Hefei National Laboratory of Physical Sciences at Microscale and School of Life Sciences, University of Science and Technology of China, Hefei 230026, China
| | - Wei Fang
- Hefei National Laboratory of Physical Sciences at Microscale and School of Life Sciences, University of Science and Technology of China, Hefei 230026, China
| | - Wenjing Sun
- Hefei National Laboratory of Physical Sciences at Microscale and School of Life Sciences, University of Science and Technology of China, Hefei 230026, China
| | - Liaoyuan A Hu
- Amgen Asia R&D Center, Amgen Research, Shanghai 201210, China
| | - Longhua Zhang
- Hefei National Laboratory of Physical Sciences at Microscale and School of Life Sciences, University of Science and Technology of China, Hefei 230026, China
| | - Pan Shi
- Hefei National Laboratory of Physical Sciences at Microscale and School of Life Sciences, University of Science and Technology of China, Hefei 230026, China
| | - Changlin Tian
- Hefei National Laboratory of Physical Sciences at Microscale and School of Life Sciences, University of Science and Technology of China, Hefei 230026, China
- High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei 230030, China
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193
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Zhang H, Chen LN, Yang D, Mao C, Shen Q, Feng W, Shen DD, Dai A, Xie S, Zhou Y, Qin J, Sun JP, Scharf DH, Hou T, Zhou T, Wang MW, Zhang Y. Structural insights into ligand recognition and activation of the melanocortin-4 receptor. Cell Res 2021; 31:1163-1175. [PMID: 34433901 DOI: 10.1038/s41422-021-00552-3] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2021] [Accepted: 07/27/2021] [Indexed: 12/12/2022] Open
Abstract
Melanocortin-4 receptor (MC4R) plays a central role in the regulation of energy homeostasis. Its high sequence similarity to other MC receptor family members, low agonist selectivity and the lack of structural information concerning MC4R-specific activation have hampered the development of MC4R-seletive therapeutics to treat obesity. Here, we report four high-resolution structures of full-length MC4R in complex with the heterotrimeric Gs protein stimulated by the endogenous peptide ligand α-MSH, FDA-approved drugs afamelanotide (Scenesse™) and bremelanotide (Vyleesi™), and a selective small-molecule ligand THIQ, respectively. Together with pharmacological studies, our results reveal the conserved binding mode of peptidic agonists, the distinctive molecular details of small-molecule agonist recognition underlying receptor subtype selectivity, and a distinct activation mechanism for MC4R, thereby offering new insights into G protein coupling. Our work may facilitate the discovery of selective therapeutic agents targeting MC4R.
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Affiliation(s)
- Huibing Zhang
- Department of Biophysics and Department of Pathology of Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.,Liangzhu Laboratory, Zhejiang University Medical Center, Hangzhou, Zhejiang, China.,MOE Frontier Science Center for Brain Research and Brain-Machine Integration, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.,Key Laboratory of Immunity and Inflammatory Diseases of Zhejiang Province, Hangzhou, Zhejiang, China
| | - Li-Nan Chen
- Department of Biophysics and Department of Pathology of Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.,Liangzhu Laboratory, Zhejiang University Medical Center, Hangzhou, Zhejiang, China.,MOE Frontier Science Center for Brain Research and Brain-Machine Integration, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.,Key Laboratory of Immunity and Inflammatory Diseases of Zhejiang Province, Hangzhou, Zhejiang, China
| | - Dehua Yang
- The CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China.,The National Center for Drug Screening, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Chunyou Mao
- Department of Biophysics and Department of Pathology of Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.,Liangzhu Laboratory, Zhejiang University Medical Center, Hangzhou, Zhejiang, China.,MOE Frontier Science Center for Brain Research and Brain-Machine Integration, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.,Key Laboratory of Immunity and Inflammatory Diseases of Zhejiang Province, Hangzhou, Zhejiang, China
| | - Qingya Shen
- Department of Biophysics and Department of Pathology of Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.,Liangzhu Laboratory, Zhejiang University Medical Center, Hangzhou, Zhejiang, China.,MOE Frontier Science Center for Brain Research and Brain-Machine Integration, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.,Key Laboratory of Immunity and Inflammatory Diseases of Zhejiang Province, Hangzhou, Zhejiang, China
| | - Wenbo Feng
- School of Pharmacy, Fudan University, Shanghai, China
| | - Dan-Dan Shen
- Department of Biophysics and Department of Pathology of Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.,Liangzhu Laboratory, Zhejiang University Medical Center, Hangzhou, Zhejiang, China.,MOE Frontier Science Center for Brain Research and Brain-Machine Integration, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.,Key Laboratory of Immunity and Inflammatory Diseases of Zhejiang Province, Hangzhou, Zhejiang, China
| | - Antao Dai
- The CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China.,The National Center for Drug Screening, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
| | - Shanshan Xie
- Department of Cell Biology and Cancer Institute of the Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China; Institute of Gastroenterology, Zhejiang University, Hangzhou, China; Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Hangzhou, Zhejiang, China; Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
| | - Yan Zhou
- The CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China.,The National Center for Drug Screening, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
| | - Jiao Qin
- Department of Biophysics and Department of Pathology of Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.,Liangzhu Laboratory, Zhejiang University Medical Center, Hangzhou, Zhejiang, China.,MOE Frontier Science Center for Brain Research and Brain-Machine Integration, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.,Key Laboratory of Immunity and Inflammatory Diseases of Zhejiang Province, Hangzhou, Zhejiang, China
| | - Jin-Peng Sun
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Peking University; Key Laboratory of Molecular Cardiovascular Science, Ministry of Education, Beijing, China.,Key Laboratory Experimental Teratology of the Ministry of Education, Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, China
| | - Daniel H Scharf
- Department of Microbiology and The Children's Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Tingjun Hou
- Innovation Institute for Artificial Intelligence in Medicine of Zhejiang University, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, Zhejiang, China
| | - Tianhua Zhou
- Department of Cell Biology and Cancer Institute of the Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China; Institute of Gastroenterology, Zhejiang University, Hangzhou, China; Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Hangzhou, Zhejiang, China; Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
| | - Ming-Wei Wang
- The CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China. .,The National Center for Drug Screening, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China. .,University of Chinese Academy of Sciences, Beijing, China. .,School of Pharmacy, Fudan University, Shanghai, China. .,School of Life Science and Technology, ShanghaiTech University, Shanghai, China. .,Department of Pharmacology, Fudan University, Shanghai, China.
| | - Yan Zhang
- Department of Biophysics and Department of Pathology of Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China. .,Liangzhu Laboratory, Zhejiang University Medical Center, Hangzhou, Zhejiang, China. .,MOE Frontier Science Center for Brain Research and Brain-Machine Integration, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China. .,Key Laboratory of Immunity and Inflammatory Diseases of Zhejiang Province, Hangzhou, Zhejiang, China.
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194
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Chandore H, Raj AK, Lokhande KB, Swamy KV, Pal JK, Sharma NK. An Intracellular Tripeptide Arg-His-Trp of Serum Origin Detected in MCF-7 Cells Is A Possible Agonist to β2 Adrenoceptor. Protein Pept Lett 2021; 28:1191-1202. [PMID: 34397320 DOI: 10.2174/0929866528666210816114901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2021] [Revised: 05/29/2021] [Accepted: 06/08/2021] [Indexed: 11/22/2022]
Abstract
BACKGROUND The need of agonists and antagonists of β2 adrenoceptor (β2AR) is warranted in various human disease conditions including cancer, cardiovascular and other metabolic disorders. However, the sources of agonists of β2AR are diverse in nature. Interestingly, there is a complete gap in the exploration of agonists of β2AR from serum that is a well-known component of culture media which supports growth and proliferation of normal and cancer cells in vitro. METHODS In this paper, we employed a novel vertical tube gel electrophoresis (VTGE)-assisted purification of intracellular metabolites of MCF-7 cells grown in vitro in complete media with fetal bovine serum (FBS). Intracellular metabolites of MCF-7 cells were then analyzed by LC-HRMS. Identified intracellular tripeptides of FBS origin were evaluated for their molecular interactions with various extracellular and intracellular receptors including β2AR (PDB ID: 2RH1) by employing molecular docking and molecular dynamics simulations (MDS). A known agonist of β2AR, isoproterenol was used as a positive control in molecular docking and MDS analyses. RESULTS We report here identification of a few novel intracellular tripeptides, namely Arg-His-Trp, (PubChem CID-145453842), Pro-Ile-Glu, (PubChem CID-145457492), Cys-Gln-Gln, (PubChem CID-71471965), Glu-Glu-Lys, (PubChem CID-11441068) and Gly-Cys-Leu (PubChem CID-145455600) of FBS origin in MCF-7 cells. Molecular docking and MDS analyses revealed that among these molecules, the tripeptide Arg-His-Trp shows a favorable binding affinity with β2AR (-9.8 Kcal/mol). The agonistic effect of Arg-His-Trp is significant and comparable with that of a known agonist of β2AR, isoproterenol. CONCLUSION In conclusion, we identified a unique Arg-His-Trp tripeptide of FBS origin in MCF-7 cells by employing a novel approach. This unique tripeptide Arg-His-Trp is suggested to be a potential agonist of β2AR and it may have applications in the context of various human diseases like bronchial asthma and chronic obstructive pulmonary disease (COPD).
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Affiliation(s)
- Hritik Chandore
- Cancer and Translational Research Lab, Dr. D.Y. Patil Biotechnology & Bioinformatics Institute, Dr. D.Y. Patil Vidyapeeth, Pune, Maharashtra, India
| | - Ajay Kumar Raj
- Cancer and Translational Research Lab, Dr. D.Y. Patil Biotechnology & Bioinformatics Institute, Dr. D.Y. Patil Vidyapeeth, Pune, Maharashtra, India
| | - Kiran Bharat Lokhande
- Bioinformatics Research Laboratory, Dr. D. Y. Patil Biotechnology and Bioinformatics Institute, Dr. D. Y. Patil Vidyapeeth, Pune, Maharashtra, India
| | - K Venkateswara Swamy
- Bioinformatics Research Laboratory, Dr. D. Y. Patil Biotechnology and Bioinformatics Institute, Dr. D. Y. Patil Vidyapeeth, Pune, Maharashtra, India
| | - Jayanta K Pal
- Cancer and Translational Research Lab, Dr. D.Y. Patil Biotechnology & Bioinformatics Institute, Dr. D.Y. Patil Vidyapeeth, Pune, Maharashtra, India
| | - Nilesh Kumar Sharma
- Cancer and Translational Research Lab, Dr. D.Y. Patil Biotechnology & Bioinformatics Institute, Dr. D.Y. Patil Vidyapeeth, Pune, Maharashtra, India
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195
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The G protein-first activation mechanism of opioid receptors by Gi protein and agonists. QRB DISCOVERY 2021. [PMID: 37529677 PMCID: PMC10392629 DOI: 10.1017/qrd.2021.7] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
AbstractWe report the G protein-first mechanism for activation of G protein-coupled receptors (GPCR) for the three closest subtypes of the opioid receptors (OR), μOR, κOR and δOR. We find that they couple to the inactive Gi protein-bound guanosine diphosphate (GDP) prior to agonist binding. The inactive Gi protein forms anchors to the intracellular loops of the inactive apo-μOR, apo-κOR and apo-δOR, inducing opening of the cytoplasmic region to form a pre-activated state that holds Gi protein in place until agonist binds. Then, agonist binds to μOR, κOR and δOR already complexed with Gi protein, to trigger the Gαi to open up the tightly coupled GDP binding site, making GDP accessible for GTP exchange, an essential step for Gi signalling. We show that the agonist alone cannot open the intracellular region of μOR and κOR, requiring Gi protein to open the cytoplasmic region by itself. We consider that this G protein-first mechanism may apply to activation of other Class A GPCRs. However, for δOR, agonist binding can open up the intracellular region to encourage Gi protein recruitment. Thus, activation of Gi protein mediated by δOR favourably may proceed with either ligand-first or G protein-first activation mechanisms.
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196
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Abstract
Nanobodies have emerged as useful tools to study G protein-coupled receptor (GPCR) structure, dynamic, and subcellular localization. Initially, several nanobodies have been developed as chaperones to facilitate GPCR crystallization. To explore their potential as biosensors to monitor receptor activation and dynamics, we here described protocols to characterize nanobody's interaction with GPCRs and their application as probes for protein identification and visualization on the cellular level. We also introduced a chimeric approach to enable a kappa-opioid receptor derived nanobody to bind to other GPCRs, including orphan GPCRs whose endogenous ligand or intracellular transducers are unknown. This approach provides a reporter assay to identify tool molecules to study the function of orphan GPCRs.
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Affiliation(s)
- Amal El Daibani
- Department of Anesthesiology, Washington University School of Medicine, St. Louis, MO, United States
| | - Tao Che
- Department of Anesthesiology, Washington University School of Medicine, St. Louis, MO, United States; Center for Clinical Pharmacology, University of Health Sciences and Pharmacy in St. Louis and Washington University School of Medicine, St. Louis, MO, United States.
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197
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Rathinaswamy MK, Fleming KD, Dalwadi U, Pardon E, Harris NJ, Yip CK, Steyaert J, Burke JE. HDX-MS-optimized approach to characterize nanobodies as tools for biochemical and structural studies of class IB phosphoinositide 3-kinases. Structure 2021; 29:1371-1381.e6. [PMID: 34348129 DOI: 10.1016/j.str.2021.07.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Revised: 06/07/2021] [Accepted: 07/15/2021] [Indexed: 10/20/2022]
Abstract
There is considerable interest in developing antibodies as modulators of signaling pathways. One of the most important signaling pathways in higher eukaryotes is the phosphoinositide 3-kinase (PI3K) pathway, which plays fundamental roles in growth, metabolism, and immunity. The class IB PI3K, PI3Kγ, is a heterodimeric complex composed of a catalytic p110γ subunit bound to a p101 or p84 regulatory subunit. PI3Kγ is a critical component in multiple immune signaling processes and is dependent on activation by Ras and G protein-coupled receptors (GPCRs) to mediate its cellular roles. Here we describe the rapid and efficient characterization of multiple PI3Kγ binding single-chain camelid nanobodies using hydrogen-deuterium exchange (HDX) mass spectrometry (MS) for structural and biochemical studies. We identify nanobodies that stimulated lipid kinase activity, block Ras activation, and specifically inhibited p101-mediated GPCR activation. Overall, our work reveals insight into PI3Kγ regulation and identifies sites that may be exploited for therapeutic development.
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Affiliation(s)
- Manoj K Rathinaswamy
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, British Columbia V8W 2Y2, Canada
| | - Kaelin D Fleming
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, British Columbia V8W 2Y2, Canada
| | - Udit Dalwadi
- Life Sciences Institute, Department of Biochemistry and Molecular Biology, The University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
| | - Els Pardon
- Structural Biology Brussels, Vrije Universiteit Brussel (VUB), Brussels, Belgium; VIB-VUB Center for Structural Biology, VIB, Brussels, Belgium
| | - Noah J Harris
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, British Columbia V8W 2Y2, Canada
| | - Calvin K Yip
- Life Sciences Institute, Department of Biochemistry and Molecular Biology, The University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
| | - Jan Steyaert
- Structural Biology Brussels, Vrije Universiteit Brussel (VUB), Brussels, Belgium; VIB-VUB Center for Structural Biology, VIB, Brussels, Belgium
| | - John E Burke
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, British Columbia V8W 2Y2, Canada; Life Sciences Institute, Department of Biochemistry and Molecular Biology, The University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada.
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198
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Nagiri C, Kobayashi K, Tomita A, Kato M, Kobayashi K, Yamashita K, Nishizawa T, Inoue A, Shihoya W, Nureki O. Cryo-EM structure of the β3-adrenergic receptor reveals the molecular basis of subtype selectivity. Mol Cell 2021; 81:3205-3215.e5. [PMID: 34314699 DOI: 10.1016/j.molcel.2021.06.024] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2020] [Revised: 04/17/2021] [Accepted: 06/21/2021] [Indexed: 11/30/2022]
Abstract
The β3-adrenergic receptor (β3AR) is predominantly expressed in adipose tissue and urinary bladder and has emerged as an attractive drug target for the treatment of type 2 diabetes, obesity, and overactive bladder (OAB). Here, we report the cryogenic electron microscopy structure of the β3AR-Gs signaling complex with the selective agonist mirabegron, a first-in-class drug for OAB. Comparison of this structure with the previously reported β1AR and β2AR structures reveals a receptor activation mechanism upon mirabegron binding to the orthosteric site. Notably, the narrower exosite in β3AR creates a perpendicular pocket for mirabegron. Mutational analyses suggest that a combination of both the exosite shape and the amino-acid-residue substitutions defines the drug selectivity of the βAR agonists. Our findings provide a molecular basis for βAR subtype selectivity, allowing the design of more-selective agents with fewer adverse effects.
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Affiliation(s)
- Chisae Nagiri
- Department of Biological Sciences, Graduate School of Science, the University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Kazuhiro Kobayashi
- Department of Biological Sciences, Graduate School of Science, the University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Atsuhiro Tomita
- Department of Biological Sciences, Graduate School of Science, the University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Masahiko Kato
- Department of Biological Sciences, Graduate School of Science, the University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Kan Kobayashi
- Department of Biological Sciences, Graduate School of Science, the University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Keitaro Yamashita
- Department of Biological Sciences, Graduate School of Science, the University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Tomohiro Nishizawa
- Department of Biological Sciences, Graduate School of Science, the University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Asuka Inoue
- Graduate School of Pharmaceutical Sciences, Tohoku University, 6-3, Aoba, Aramaki, Aoba-ku, Sendai, Miyagi 980-8578, Japan.
| | - Wataru Shihoya
- Department of Biological Sciences, Graduate School of Science, the University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
| | - Osamu Nureki
- Department of Biological Sciences, Graduate School of Science, the University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
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199
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Yan Y, Mukherjee S, Harikumar KG, Strutzenberg TS, Zhou XE, Suino-Powell K, Xu TH, Sheldon RD, Lamp J, Brunzelle JS, Radziwon K, Ellis A, Novick SJ, Vega IE, Jones RG, Miller LJ, Xu HE, Griffin PR, Kossiakoff AA, Melcher K. Structure of an AMPK complex in an inactive, ATP-bound state. Science 2021; 373:413-419. [PMID: 34437114 PMCID: PMC8428800 DOI: 10.1126/science.abe7565] [Citation(s) in RCA: 45] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2020] [Revised: 03/31/2021] [Accepted: 06/07/2021] [Indexed: 12/15/2022]
Abstract
Adenosine monophosphate (AMP)-activated protein kinase (AMPK) regulates metabolism in response to the cellular energy states. Under energy stress, AMP stabilizes the active AMPK conformation, in which the kinase activation loop (AL) is protected from protein phosphatases, thus keeping the AL in its active, phosphorylated state. At low AMP:ATP (adenosine triphosphate) ratios, ATP inhibits AMPK by increasing AL dynamics and accessibility. We developed conformation-specific antibodies to trap ATP-bound AMPK in a fully inactive, dynamic state and determined its structure at 3.5-angstrom resolution using cryo-electron microscopy. A 180° rotation and 100-angstrom displacement of the kinase domain fully exposes the AL. On the basis of the structure and supporting biophysical data, we propose a multistep mechanism explaining how adenine nucleotides and pharmacological agonists modulate AMPK activity by altering AL phosphorylation and accessibility.
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Affiliation(s)
- Yan Yan
- Department of Structural Biology, Van Andel Institute, Grand Rapids, MI 49503, USA
| | - Somnath Mukherjee
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL 60637, USA
| | - Kaleeckal G Harikumar
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Scottsdale, AZ 85259, USA
| | - Timothy S Strutzenberg
- Department of Molecular Medicine, The Scripps Research Institute, Scripps Florida, Jupiter, FL 33458, USA
| | - X Edward Zhou
- Department of Structural Biology, Van Andel Institute, Grand Rapids, MI 49503, USA
| | - Kelly Suino-Powell
- Department of Structural Biology, Van Andel Institute, Grand Rapids, MI 49503, USA
| | - Ting-Hai Xu
- Department of Structural Biology, Van Andel Institute, Grand Rapids, MI 49503, USA
- Center for Epigenetics, Van Andel Institute, Grand Rapids, MI 49503, USA
| | - Ryan D Sheldon
- Metabolic and Nutritional Programming, Center for Cancer and Cell Biology, Van Andel Institute, Grand Rapids, MI 49503, USA
| | - Jared Lamp
- Integrated Mass Spectrometry Unit, Department of Translational Neuroscience, Michigan State University College of Human Medicine, Grand Rapids Research Center, Grand Rapids, MI 49503, USA
| | - Joseph S Brunzelle
- Life Sciences Collaborative Access Team, Northwestern University Synchrotron Research Center, Northwestern University, Argonne, IL 60439, USA
| | - Katarzyna Radziwon
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL 60637, USA
| | - Abigail Ellis
- Metabolic and Nutritional Programming, Center for Cancer and Cell Biology, Van Andel Institute, Grand Rapids, MI 49503, USA
| | - Scott J Novick
- Department of Molecular Medicine, The Scripps Research Institute, Scripps Florida, Jupiter, FL 33458, USA
| | - Irving E Vega
- Integrated Mass Spectrometry Unit, Department of Translational Neuroscience, Michigan State University College of Human Medicine, Grand Rapids Research Center, Grand Rapids, MI 49503, USA
| | - Russell G Jones
- Metabolic and Nutritional Programming, Center for Cancer and Cell Biology, Van Andel Institute, Grand Rapids, MI 49503, USA
| | - Laurence J Miller
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Scottsdale, AZ 85259, USA
| | - H Eric Xu
- Center for Structure and Function of Drug Targets, The CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences (CAS), Shanghai 201203, China
| | - Patrick R Griffin
- Department of Molecular Medicine, The Scripps Research Institute, Scripps Florida, Jupiter, FL 33458, USA
| | - Anthony A Kossiakoff
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL 60637, USA
- Institute of Biophysical Dynamics, University of Chicago, Chicago, IL 60637, USA
| | - Karsten Melcher
- Department of Structural Biology, Van Andel Institute, Grand Rapids, MI 49503, USA.
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200
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Goulding J, Kondrashov A, Mistry SJ, Melarangi T, Vo NTN, Hoang DM, White CW, Denning C, Briddon SJ, Hill SJ. The use of fluorescence correlation spectroscopy to monitor cell surface β2-adrenoceptors at low expression levels in human embryonic stem cell-derived cardiomyocytes and fibroblasts. FASEB J 2021; 35:e21398. [PMID: 33710675 DOI: 10.1096/fj.202002268r] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Revised: 01/05/2021] [Accepted: 01/12/2021] [Indexed: 12/31/2022]
Abstract
The importance of cell phenotype in determining the molecular mechanisms underlying β2 -adrenoceptor (β2AR) function has been noted previously when comparing responses in primary cells and recombinant model cell lines. Here, we have generated haplotype-specific SNAP-tagged β2AR human embryonic stem (ES) cell lines and applied fluorescence correlation spectroscopy (FCS) to study cell surface receptors in progenitor cells and in differentiated fibroblasts and cardiomyocytes. FCS was able to quantify SNAP-tagged β2AR number and diffusion in both ES-derived cardiomyocytes and CRISPR/Cas9 genome-edited HEK293T cells, where the expression level was too low to detect using standard confocal microscopy. These studies demonstrate the power of FCS in investigating cell surface β2ARs at the very low expression levels often seen in endogenously expressing cells. Furthermore, the use of ES cell technology in combination with FCS allowed us to demonstrate that cell surface β2ARs internalize in response to formoterol-stimulation in ES progenitor cells but not following their differentiation into ES-derived fibroblasts. This indicates that the process of agonist-induced receptor internalization is strongly influenced by cell phenotype and this may have important implications for drug treatment with long-acting β2AR agonists.
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Affiliation(s)
- Joëlle Goulding
- Centre of Membrane Proteins and Receptors (COMPARE), University of Nottingham, Nottingham, UK.,Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Nottingham, UK
| | - Alexander Kondrashov
- Centre of Membrane Proteins and Receptors (COMPARE), University of Nottingham, Nottingham, UK.,Division of Cancer & Stem Cells, University of Nottingham Biodiscovery Institute, University Park, Nottingham, UK
| | - Sarah J Mistry
- Centre of Membrane Proteins and Receptors (COMPARE), University of Nottingham, Nottingham, UK.,School of Pharmacy, University of Nottingham, Nottingham, UK
| | - Tony Melarangi
- Division of Cancer & Stem Cells, University of Nottingham Biodiscovery Institute, University Park, Nottingham, UK
| | - Nguyen T N Vo
- Division of Cancer & Stem Cells, University of Nottingham Biodiscovery Institute, University Park, Nottingham, UK
| | - Duc M Hoang
- Division of Cancer & Stem Cells, University of Nottingham Biodiscovery Institute, University Park, Nottingham, UK.,Department of Cellular Manufacturing, Vinmec Research Institute of Stem Cell and Gene Technology, Hanoi, Vietnam
| | - Carl W White
- Centre of Membrane Proteins and Receptors (COMPARE), University of Nottingham, Nottingham, UK.,Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Nottingham, UK.,Harry Perkins Institute of Medical Research and Centre for Medical Research, QEII Medical Centre, The University of Western Australia, Nedlands, WA, Australia.,Australian Research Council Centre for Personalised Therapeutics Technologies, Melbourne, VIC, Australia
| | - Chris Denning
- Centre of Membrane Proteins and Receptors (COMPARE), University of Nottingham, Nottingham, UK.,Division of Cancer & Stem Cells, University of Nottingham Biodiscovery Institute, University Park, Nottingham, UK
| | - Stephen J Briddon
- Centre of Membrane Proteins and Receptors (COMPARE), University of Nottingham, Nottingham, UK.,Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Nottingham, UK
| | - Stephen J Hill
- Centre of Membrane Proteins and Receptors (COMPARE), University of Nottingham, Nottingham, UK.,Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham, Nottingham, UK
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