1
|
Sajkowska JJ, Tsang CH, Kozielewicz P. Application of FRET- and BRET-based live-cell biosensors in deorphanization and ligand discovery studies on orphan G protein-coupled receptors. SLAS DISCOVERY : ADVANCING LIFE SCIENCES R & D 2024; 29:100174. [PMID: 39084335 DOI: 10.1016/j.slasd.2024.100174] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2024] [Revised: 07/16/2024] [Accepted: 07/26/2024] [Indexed: 08/02/2024]
Abstract
Bioluminescence- and fluorescence-based resonance energy transfer assays have gained considerable attention in pharmacological research as high-throughput scalable tools applicable to drug discovery. To this end, G protein-coupled receptors represent the biggest target class for marketed drugs, and among them, orphan G protein-coupled receptors have the biggest untapped therapeutic potential. In this review, the cases where biophysical methods, BRET and FRET, were employed for deorphanization and ligand discovery studies on orphan G protein-coupled receptors are listed and discussed.
Collapse
Affiliation(s)
- Joanna J Sajkowska
- Department of Medical Biochemistry and Biophysics, Karolinska Institute, Stockholm, Sweden; Department of Organic and Physical Chemistry, Faculty of Pharmacy, Medical University of Warsaw, Warsaw, Poland; Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden
| | - Choi Har Tsang
- Department of Physiology and Pharmacology, Molecular Pharmacology of GPCRs, Karolinska Institute, Stockholm, Sweden
| | - Paweł Kozielewicz
- Department of Physiology and Pharmacology, Molecular Pharmacology of GPCRs, Karolinska Institute, Stockholm, Sweden.
| |
Collapse
|
2
|
Chinellato M, Gasparotto M, Quarta S, Ruvoletto M, Biasiolo A, Filippini F, Spiezia L, Cendron L, Pontisso P. 1-Piperidine Propionic Acid as an Allosteric Inhibitor of Protease Activated Receptor-2. Pharmaceuticals (Basel) 2023; 16:1486. [PMID: 37895957 PMCID: PMC10610151 DOI: 10.3390/ph16101486] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Revised: 10/12/2023] [Accepted: 10/16/2023] [Indexed: 10/29/2023] Open
Abstract
In the last decades, studies on the inflammatory signaling pathways in multiple pathological contexts have revealed new targets for novel therapies. Among the family of G-protein-coupled Proteases Activated Receptors, PAR2 was identified as a driver of the inflammatory cascade in many pathologies, ranging from autoimmune disease to cancer metastasis. For this reason, many efforts have been focused on the development of potential antagonists of PAR2 activity. This work focuses on a small molecule, 1-Piperidine Propionic Acid (1-PPA), previously described to be active against inflammatory processes, but whose target is still unknown. Stabilization effects observed by cellular thermal shift assay coupled to in-silico investigations, including molecular docking and molecular dynamics simulations, suggested that 1-PPA binds PAR2 in an allosteric pocket of the receptor inactive conformation. Functional studies revealed the antagonist effects on MAPKs signaling and on platelet aggregation, processes mediated by PAR family members, including PAR2. Since the allosteric pocket binding 1-PPA is highly conserved in all the members of the PAR family, the evidence reported here suggests that 1-PPA could represent a promising new small molecule targeting PARs with antagonistic activity.
Collapse
Affiliation(s)
- Monica Chinellato
- Department of Medicine, University of Padova, 35121 Padova, Italy; (M.C.); (S.Q.); (M.R.); (A.B.)
| | - Matteo Gasparotto
- Department of Biology, University of Padova, 35121 Padova, Italy; (M.G.); (F.F.); (L.C.)
| | - Santina Quarta
- Department of Medicine, University of Padova, 35121 Padova, Italy; (M.C.); (S.Q.); (M.R.); (A.B.)
| | - Mariagrazia Ruvoletto
- Department of Medicine, University of Padova, 35121 Padova, Italy; (M.C.); (S.Q.); (M.R.); (A.B.)
| | - Alessandra Biasiolo
- Department of Medicine, University of Padova, 35121 Padova, Italy; (M.C.); (S.Q.); (M.R.); (A.B.)
| | - Francesco Filippini
- Department of Biology, University of Padova, 35121 Padova, Italy; (M.G.); (F.F.); (L.C.)
| | - Luca Spiezia
- Department of Medicine, University of Padova, 35121 Padova, Italy; (M.C.); (S.Q.); (M.R.); (A.B.)
| | - Laura Cendron
- Department of Biology, University of Padova, 35121 Padova, Italy; (M.G.); (F.F.); (L.C.)
| | - Patrizia Pontisso
- Department of Medicine, University of Padova, 35121 Padova, Italy; (M.C.); (S.Q.); (M.R.); (A.B.)
| |
Collapse
|
3
|
Biophysical investigations of class A GPCRs. Biochimie 2023; 205:86-94. [PMID: 36220484 DOI: 10.1016/j.biochi.2022.10.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Revised: 08/29/2022] [Accepted: 10/04/2022] [Indexed: 11/23/2022]
Abstract
G protein-coupled receptors (GPCRs) play a central role in cellular communication, converting external stimuli into intracellular responses. GPCRs bind a very broad panel of ligands, such as hormones, neurotransmitters, peptides and lipids. Ligand binding triggers a series of receptor conformational rearrangements, enabling the coupling to intracellular partners and the activation of signaling cascades. The major breakthrough in GPCRs structural biology of the past decade has considerably advanced our understanding of GPCR activation. However, structural information cannot fully explain the molecular details of GPCRs pharmacology. Biophysical investigations reveal that GPCRs are very dynamic proteins, capable of exploring a wide range of conformational states. Binding to ligands of various pharmacological classes, as well as intracellular effectors and allosteric modulators, can shift the equilibrium between these states and the kinetic of interconversions among the different conformers. Investigation of GPCR dynamic interplay is therefore important to better understand the complex pharmacology and signaling profile of these receptors.
Collapse
|
4
|
Schöppe J, Ehrenmann J, Waltenspühl Y, Plückthun A. Universal platform for the generation of thermostabilized GPCRs that crystallize in LCP. Nat Protoc 2022; 17:698-726. [PMID: 35140409 DOI: 10.1038/s41596-021-00660-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2021] [Accepted: 11/08/2021] [Indexed: 12/13/2022]
Abstract
Structural studies of G-protein-coupled receptors (GPCRs) are often limited by difficulties in obtaining well-diffracting crystals suitable for high-resolution structure determination. During the past decade, crystallization in lipidic cubic phase (LCP) has become the most successful and widely used technique for obtaining such crystals. Despite often intense efforts, many GPCRs remain refractory to crystallization, even if receptors can be purified in sufficient amounts. To address this issue, we have developed a highly efficient screening and stabilization strategy for GPCRs, based on a fluorescence thermal stability assay readout, which seems to correlate particularly well with those GPCR constructs that remain native during incorporation into the LCP. Detailed protocols are provided for rapid and cost-efficient mutant and construct generation using sequence- and ligation-independent cloning, high-throughput magnetic bead-based protein purification from small-scale expressions in mammalian cells, the screening and optimal combination of mutations for increased receptor thermostability and the rapid identification of suitable chimeric fusion protein constructs for successful crystallization in LCP. We exemplify the method on three receptors from two different classes: the neurokinin 1 receptor, the oxytocin receptor and the parathyroid hormone 1 receptor.
Collapse
Affiliation(s)
- Jendrik Schöppe
- Department of Biochemistry, University of Zürich, Zurich, Switzerland.,Novo Nordisk A/S, Måløv, Denmark
| | - Janosch Ehrenmann
- Department of Biochemistry, University of Zürich, Zurich, Switzerland.,leadXpro AG, PARK InnovAARE, Villigen, Switzerland
| | - Yann Waltenspühl
- Department of Biochemistry, University of Zürich, Zurich, Switzerland
| | - Andreas Plückthun
- Department of Biochemistry, University of Zürich, Zurich, Switzerland.
| |
Collapse
|
5
|
Maruta N, Trusov Y, Jones AM, Botella JR. Heterotrimeric G Proteins in Plants: Canonical and Atypical Gα Subunits. Int J Mol Sci 2021; 22:11841. [PMID: 34769272 PMCID: PMC8584482 DOI: 10.3390/ijms222111841] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Revised: 10/26/2021] [Accepted: 10/27/2021] [Indexed: 11/16/2022] Open
Abstract
Heterotrimeric GTP-binding proteins (G proteins), consisting of Gα, Gβ and Gγ subunits, transduce signals from a diverse range of extracellular stimuli, resulting in the regulation of numerous cellular and physiological functions in Eukaryotes. According to the classic G protein paradigm established in animal models, the bound guanine nucleotide on a Gα subunit, either guanosine diphosphate (GDP) or guanosine triphosphate (GTP) determines the inactive or active mode, respectively. In plants, there are two types of Gα subunits: canonical Gα subunits structurally similar to their animal counterparts and unconventional extra-large Gα subunits (XLGs) containing a C-terminal domain homologous to the canonical Gα along with an extended N-terminal domain. Both Gα and XLG subunits interact with Gβγ dimers and regulator of G protein signalling (RGS) protein. Plant G proteins are implicated directly or indirectly in developmental processes, stress responses, and innate immunity. It is established that despite the substantial overall similarity between plant and animal Gα subunits, they convey signalling differently including the mechanism by which they are activated. This review emphasizes the unique characteristics of plant Gα subunits and speculates on their unique signalling mechanisms.
Collapse
Affiliation(s)
- Natsumi Maruta
- School of Agriculture and Food Sciences, University of Queensland, Brisbane 4072, Australia; (N.M.); (Y.T.)
| | - Yuri Trusov
- School of Agriculture and Food Sciences, University of Queensland, Brisbane 4072, Australia; (N.M.); (Y.T.)
| | - Alan M. Jones
- Departments of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA;
- Departments of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Jose R. Botella
- School of Agriculture and Food Sciences, University of Queensland, Brisbane 4072, Australia; (N.M.); (Y.T.)
| |
Collapse
|
6
|
Schafer CT, Shumate A, Farrens DL. Novel fluorescent GPCR biosensor detects retinal equilibrium binding to opsin and active G protein and arrestin signaling conformations. J Biol Chem 2020; 295:17486-17496. [PMID: 33453993 DOI: 10.1074/jbc.ra120.014631] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Revised: 09/25/2020] [Indexed: 01/14/2023] Open
Abstract
Rhodopsin is a canonical class A photosensitive G protein-coupled receptor (GPCR), yet relatively few pharmaceutical agents targeting this visual receptor have been identified, in part due to the unique characteristics of its light-sensitive, covalently bound retinal ligands. Rhodopsin becomes activated when light isomerizes 11-cis-retinal into an agonist, all-trans-retinal (ATR), which enables the receptor to activate its G protein. We have previously demonstrated that, despite being covalently bound, ATR can display properties of equilibrium binding, yet how this is accomplished is unknown. Here, we describe a new approach for both identifying compounds that can activate and attenuate rhodopsin and testing the hypothesis that opsin binds retinal in equilibrium. Our method uses opsin-based fluorescent sensors, which directly report the formation of active receptor conformations by detecting the binding of G protein or arrestin fragments that have been fused onto the receptor's C terminus. We show that these biosensors can be used to monitor equilibrium binding of the agonist, ATR, as well as the noncovalent binding of β-ionone, an antagonist for G protein activation. Finally, we use these novel biosensors to observe ATR release from an activated, unlabeled receptor and its subsequent transfer to the sensor in real time. Taken together, these data support the retinal equilibrium binding hypothesis. The approach we describe should prove directly translatable to other GPCRs, providing a new tool for ligand discovery and mutant characterization.
Collapse
Affiliation(s)
- Christopher T Schafer
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, Oregon, USA
| | - Anthony Shumate
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, Oregon, USA
| | - David L Farrens
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, Oregon, USA.
| |
Collapse
|
7
|
Hatzipantelis C, Langiu M, Vandekolk TH, Pierce TL, Nithianantharajah J, Stewart GD, Langmead CJ. Translation-Focused Approaches to GPCR Drug Discovery for Cognitive Impairments Associated with Schizophrenia. ACS Pharmacol Transl Sci 2020; 3:1042-1062. [PMID: 33344888 PMCID: PMC7737210 DOI: 10.1021/acsptsci.0c00117] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Indexed: 01/07/2023]
Abstract
There are no effective therapeutics for cognitive impairments associated with schizophrenia (CIAS), which includes deficits in executive functions (working memory and cognitive flexibility) and episodic memory. Compounds that have entered clinical trials are inadequate in terms of efficacy and/or tolerability, highlighting a clear translational bottleneck and a need for a cohesive preclinical drug development strategy. In this review we propose hippocampal-prefrontal-cortical (HPC-PFC) circuitry underlying CIAS-relevant cognitive processes across mammalian species as a target source to guide the translation-focused discovery and development of novel, procognitive agents. We highlight several G protein-coupled receptors (GPCRs) enriched within HPC-PFC circuitry as therapeutic targets of interest, including noncanonical approaches (biased agonism and allosteric modulation) to conventional clinical targets, such as dopamine and muscarinic acetylcholine receptors, along with prospective novel targets, including the orphan receptors GPR52 and GPR139. We also describe the translational limitations of popular preclinical cognition tests and suggest touchscreen-based assays that probe cognitive functions reliant on HPC-PFC circuitry and reflect tests used in the clinic, as tests of greater translational relevance. Combining pharmacological and behavioral testing strategies based in HPC-PFC circuit function creates a cohesive, translation-focused approach to preclinical drug development that may improve the translational bottleneck currently hindering the development of treatments for CIAS.
Collapse
Affiliation(s)
- Cassandra
J. Hatzipantelis
- Drug
Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Monica Langiu
- Drug
Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Teresa H. Vandekolk
- Drug
Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Tracie L. Pierce
- Drug
Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Jess Nithianantharajah
- Florey
Institute of Neuroscience
and Mental Health, University of Melbourne, Parkville, Victoria 3052, Australia
| | - Gregory D. Stewart
- Drug
Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Christopher J. Langmead
- Drug
Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| |
Collapse
|
8
|
Njila Tchoufack EJ, Hahnfeld L, Pitschelatow G, Bennink S, Pradel G. The endoplasmic reticulum-resident serpentine receptor SR10 has important functions for asexual and sexual blood stage development of Plasmodium falciparum. Mol Biochem Parasitol 2020; 239:111315. [PMID: 32890576 DOI: 10.1016/j.molbiopara.2020.111315] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Revised: 07/13/2020] [Accepted: 07/28/2020] [Indexed: 11/28/2022]
Abstract
Serpentine receptors (SRs) are transmembrane proteins generally acting as mediators to facilitate the communication between a cell and its environment. At least six putative SR-like proteins are encoded in the genome of the malaria parasite Plasmodium falciparum. For two of them, roles in cell stress control were reported; however, for most of the SR-like proteins the functions are not yet known. In this study, we provide a first phenotypic analysis of the plasmodial SR10. The transmembrane protein is expressed in the asexual and sexual blood stages of P. falciparum. Co-localization and co-immunoprecipitation assays demonstrated an association of SR10 with the endoplasmic reticulum protein ERC. Gene disruption of SR10 leads to impaired intraerythrocytic replication and strongly reduces gametocyte numbers. We thus propose that SR10 is a protein associated with the endoplasmic reticulum that has important functions for asexual and sexual blood stage development.
Collapse
Affiliation(s)
| | - Lena Hahnfeld
- Division of Cellular and Applied Infection Biology, Institute of Biology 2, RWTH Aachen University, Aachen, Germany
| | - Georg Pitschelatow
- Division of Cellular and Applied Infection Biology, Institute of Biology 2, RWTH Aachen University, Aachen, Germany
| | - Sandra Bennink
- Division of Cellular and Applied Infection Biology, Institute of Biology 2, RWTH Aachen University, Aachen, Germany
| | - Gabriele Pradel
- Division of Cellular and Applied Infection Biology, Institute of Biology 2, RWTH Aachen University, Aachen, Germany.
| |
Collapse
|
9
|
Perturbation of the interactions of calmodulin with GRK5 using a natural product chemical probe. Proc Natl Acad Sci U S A 2019; 116:15895-15900. [PMID: 31337679 DOI: 10.1073/pnas.1818547116] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
G protein-coupled receptor (GPCR) kinases (GRKs) are responsible for initiating desensitization of activated GPCRs. GRK5 is potently inhibited by the calcium-sensing protein calmodulin (CaM), which leads to nuclear translocation of GRK5 and promotion of cardiac hypertrophy. Herein, we report the architecture of the Ca2+·CaM-GRK5 complex determined by small-angle X-ray scattering and negative-stain electron microscopy. Ca2+·CaM binds primarily to the small lobe of the kinase domain of GRK5 near elements critical for receptor interaction and membrane association, thereby inhibiting receptor phosphorylation while activating the kinase for phosphorylation of soluble substrates. To define the role of each lobe of Ca2+·CaM, we utilized the natural product malbrancheamide as a chemical probe to show that the C-terminal lobe of Ca2+·CaM regulates membrane binding while the N-terminal lobe regulates receptor phosphorylation and kinase domain activation. In cells, malbrancheamide attenuated GRK5 nuclear translocation and effectively blocked the hypertrophic response, demonstrating the utility of this natural product and its derivatives in probing Ca2+·CaM-dependent hypertrophy.
Collapse
|
10
|
Jakobs BD, Spannagel L, Purvanov V, Uetz-von Allmen E, Matti C, Legler DF. Engineering of Nanobodies Recognizing the Human Chemokine Receptor CCR7. Int J Mol Sci 2019; 20:E2597. [PMID: 31137829 PMCID: PMC6566259 DOI: 10.3390/ijms20102597] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2019] [Revised: 05/20/2019] [Accepted: 05/24/2019] [Indexed: 01/12/2023] Open
Abstract
The chemokine receptor CCR7 plays a pivotal role in health and disease. In particular, CCR7 controls homing of antigen-bearing dendritic cells and T cells to lymph nodes, where adaptive immune responses are initiated. However, CCR7 also guides T cells to inflamed synovium and thereby contributes to rheumatoid arthritis and promotes cancer cell migration and metastasis formation. Nanobodies have recently emerged as versatile tools to study G-protein-coupled receptor functions and are being tested in diagnostics and therapeutics. In this study, we designed a strategy to engineer novel nanobodies recognizing human CCR7. We generated a nanobody library based on a solved crystal structure of the nanobody Nb80 recognizing the β2-adrenergic receptor (β2AR) and by specifically randomizing two segments within complementarity determining region 1 (CDR1) and CDR3 of Nb80 known to interact with β2AR. We fused the nanobody library to one half of split-YFP in order to identify individual nanobody clones interacting with CCR7 fused to the other half of split-YFP using bimolecular fluorescence complementation. We present three novel nanobodies, termed Nb1, Nb5, and Nb38, that recognize human CCR7 without interfering with G-protein-coupling and downstream signaling. Moreover, we were able to follow CCR7 trafficking upon CCL19 triggering using Nb1, Nb5, and Nb38.
Collapse
Affiliation(s)
- Barbara D Jakobs
- Biotechnology Institute Thurgau (BITg) at the University of Konstanz, CH-8280 Kreuzlingen, Switzerland.
- Graduate School for Cellular and Biomedical Sciences, University of Bern, CH-3012 Bern, Switzerland.
| | - Lisa Spannagel
- Biotechnology Institute Thurgau (BITg) at the University of Konstanz, CH-8280 Kreuzlingen, Switzerland.
| | - Vladimir Purvanov
- Biotechnology Institute Thurgau (BITg) at the University of Konstanz, CH-8280 Kreuzlingen, Switzerland.
| | - Edith Uetz-von Allmen
- Biotechnology Institute Thurgau (BITg) at the University of Konstanz, CH-8280 Kreuzlingen, Switzerland.
| | - Christoph Matti
- Biotechnology Institute Thurgau (BITg) at the University of Konstanz, CH-8280 Kreuzlingen, Switzerland.
| | - Daniel F Legler
- Biotechnology Institute Thurgau (BITg) at the University of Konstanz, CH-8280 Kreuzlingen, Switzerland.
- Faculty of Biology, University of Konstanz, D-78464 Konstanz, Germany.
| |
Collapse
|
11
|
Peeking at G-protein-coupled receptors through the molecular dynamics keyhole. Future Med Chem 2019; 11:599-615. [DOI: 10.4155/fmc-2018-0393] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Molecular dynamics is a state of the art computational tool for the investigation of biophysics phenomenon at a molecular scale, as it enables the modeling of dynamic processes, such as conformational motions, molecular solvation and ligand binding. The recent advances in structural biology have led to a bloom in published G-protein-coupled receptor structures, representing a solid and valuable resource for molecular dynamics studies. During the last decade, indeed, a plethora of physiological and pharmacological facets of this membrane protein superfamily have been addressed by means of molecular dynamics simulations, including the activation mechanism, allosterism and, very recently, biased signaling. Here, we try to recapitulate some of the main contributions that molecular dynamics has recently produced in the field.
Collapse
|
12
|
Bennink S, von Bohl A, Ngwa CJ, Henschel L, Kuehn A, Pilch N, Weißbach T, Rosinski AN, Scheuermayer M, Repnik U, Przyborski JM, Minns AM, Orchard LM, Griffiths G, Lindner SE, Llinás M, Pradel G. A seven-helix protein constitutes stress granules crucial for regulating translation during human-to-mosquito transmission of Plasmodium falciparum. PLoS Pathog 2018; 14:e1007249. [PMID: 30133543 PMCID: PMC6122839 DOI: 10.1371/journal.ppat.1007249] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Revised: 09/04/2018] [Accepted: 07/29/2018] [Indexed: 12/16/2022] Open
Abstract
The complex life-cycle of the human malaria parasite Plasmodium falciparum requires a high degree of tight coordination allowing the parasite to adapt to changing environments. One of the major challenges for the parasite is the human-to-mosquito transmission, which starts with the differentiation of blood stage parasites into the transmissible gametocytes, followed by the rapid conversion of the gametocytes into gametes, once they are taken up by the blood-feeding Anopheles vector. In order to pre-adapt to this change of host, the gametocytes store transcripts in stress granules that encode proteins needed for parasite development in the mosquito. Here we report on a novel stress granule component, the seven-helix protein 7-Helix-1. The protein, a homolog of the human stress response regulator LanC-like 2, accumulates in stress granules of female gametocytes and interacts with ribonucleoproteins, such as CITH, DOZI, and PABP1. Malaria parasites lacking 7-Helix-1 are significantly impaired in female gametogenesis and thus transmission to the mosquito. Lack of 7-Helix-1 further leads to a deregulation of components required for protein synthesis. Consistently, inhibitors of translation could mimic the 7-Helix-1 loss-of-function phenotype. 7-Helix-1 forms a complex with the RNA-binding protein Puf2, a translational regulator of the female-specific antigen Pfs25, as well as with pfs25-coding mRNA. In accord, gametocytes deficient of 7-Helix-1 exhibit impaired Pfs25 synthesis. Our data demonstrate that 7-Helix-1 constitutes stress granules crucial for regulating the synthesis of proteins needed for life-cycle progression of Plasmodium in the mosquito vector.
Collapse
Affiliation(s)
- Sandra Bennink
- Division of Cellular and Applied Infection Biology, RWTH Aachen University, Aachen, Germany
| | - Andreas von Bohl
- Division of Cellular and Applied Infection Biology, RWTH Aachen University, Aachen, Germany
| | - Che J. Ngwa
- Division of Cellular and Applied Infection Biology, RWTH Aachen University, Aachen, Germany
| | - Leonie Henschel
- Division of Cellular and Applied Infection Biology, RWTH Aachen University, Aachen, Germany
| | - Andrea Kuehn
- Research Center for Infectious Diseases, University of Würzburg, Würzburg, Germany
| | - Nicole Pilch
- Division of Cellular and Applied Infection Biology, RWTH Aachen University, Aachen, Germany
| | - Tim Weißbach
- Division of Cellular and Applied Infection Biology, RWTH Aachen University, Aachen, Germany
| | - Alina N. Rosinski
- Division of Cellular and Applied Infection Biology, RWTH Aachen University, Aachen, Germany
| | | | - Urska Repnik
- Department of Biosciences, University of Oslo, Oslo, Norway
| | | | - Allen M. Minns
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA, United States of America
| | - Lindsey M. Orchard
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA, United States of America
| | | | - Scott E. Lindner
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA, United States of America
| | - Manuel Llinás
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA, United States of America
- Department of Chemistry & Huck Center for Malaria Research, The Pennsylvania State University, University Park, PA, United States of America
| | - Gabriele Pradel
- Division of Cellular and Applied Infection Biology, RWTH Aachen University, Aachen, Germany
| |
Collapse
|
13
|
Structural insights into G-protein-coupled receptor allostery. Nature 2018; 559:45-53. [DOI: 10.1038/s41586-018-0259-z] [Citation(s) in RCA: 194] [Impact Index Per Article: 32.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2017] [Accepted: 05/17/2018] [Indexed: 01/14/2023]
|
14
|
Thal DM, Vuckovic Z, Draper-Joyce CJ, Liang YL, Glukhova A, Christopoulos A, Sexton PM. Recent advances in the determination of G protein-coupled receptor structures. Curr Opin Struct Biol 2018; 51:28-34. [PMID: 29547818 DOI: 10.1016/j.sbi.2018.03.002] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2017] [Revised: 02/28/2018] [Accepted: 03/02/2018] [Indexed: 02/06/2023]
Abstract
G protein-coupled receptors (GPCRs) are the largest superfamily of cell surface receptor proteins and are important drug targets for many human diseases. In the last decade, remarkable progress has been made in the determination of atomic structures of GPCRs with over 200 structures from 53 unique receptors having been solved. Technological advances in protein engineering and X-ray crystallography have driven much of the progress to date. However, recent advances in cryo-electron microscopy have facilitated the structural determination of three new structures of active-state GPCRs in complex with heterotrimeric G protein. These advances have led to significant breakthroughs in our understanding of GPCR biology including not only how signal transducers such as G proteins or arrestins interact with receptors, but also pave the way for future structure-based drug design.
Collapse
Affiliation(s)
- David M Thal
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville 3052, Victoria, Australia.
| | - Ziva Vuckovic
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville 3052, Victoria, Australia
| | - Christopher J Draper-Joyce
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville 3052, Victoria, Australia
| | - Yi-Lynn Liang
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville 3052, Victoria, Australia
| | - Alisa Glukhova
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville 3052, Victoria, Australia
| | - Arthur Christopoulos
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville 3052, Victoria, Australia
| | - Patrick M Sexton
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville 3052, Victoria, Australia.
| |
Collapse
|
15
|
Detection and Quantitative Analysis of Dynamic GPCRs Interactions Using Flow Cytometry-Based FRET. RECEPTOR-RECEPTOR INTERACTIONS IN THE CENTRAL NERVOUS SYSTEM 2018. [DOI: 10.1007/978-1-4939-8576-0_14] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
|
16
|
Abstract
G protein-coupled receptors (GPCRs) are cell surface receptors that relay extracellular signals to the inside of the cells. C-X-C chemokine receptor 4 (CXCR4) is a GPCR that undergoes receptor internalization and recycling upon stimulation with its cognate ligand, C-X-C chemokine 12 (CXCL12). Using this receptor/ligand pair we describe the use of two techniques, enzyme-linked immunosorbent assay (ELISA) and flow cytometry, widely used to quantify GPCR internalization from the plasma membrane and its return to the cell surface by recycling.
Collapse
Affiliation(s)
- Amanda M Nevins
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Adriano Marchese
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, WI, USA.
| |
Collapse
|
17
|
Abstract
Apelin and apela (ELABELA/ELA/Toddler) are two peptide ligands for a class A G-protein-coupled receptor named the apelin receptor (AR/APJ/APLNR). Ligand-AR interactions have been implicated in regulation of the adipoinsular axis, cardiovascular system, and central nervous system alongside pathological processes. Each ligand may be processed into a variety of bioactive isoforms endogenously, with apelin ranging from 13 to 55 amino acids and apela from 11 to 32, typically being cleaved C-terminal to dibasic proprotein convertase cleavage sites. The C-terminal region of the respective precursor protein is retained and is responsible for receptor binding and subsequent activation. Interestingly, both apelin and apela exhibit isoform-dependent variability in potency and efficacy under various physiological and pathological conditions, but most studies focus on a single isoform. Biophysical behavior and structural properties of apelin and apela isoforms show strong correlations with functional studies, with key motifs now well determined for apelin. Unlike its ligands, the AR has been relatively difficult to characterize by biophysical techniques, with most characterization to date being focused on effects of mutagenesis. This situation may improve following a recently reported AR crystal structure, but there are still barriers to overcome in terms of comprehensive biophysical study. In this review, we summarize the three components of the apelinergic system in terms of structure-function correlation, with a particular focus on isoform-dependent properties, underlining the potential for regulation of the system through multiple endogenous ligands and isoforms, isoform-dependent pharmacological properties, and biological membrane-mediated receptor interaction. © 2018 American Physiological Society. Compr Physiol 8:407-450, 2018.
Collapse
Affiliation(s)
- Kyungsoo Shin
- Department of Biochemistry & Molecular Biology, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Calem Kenward
- Department of Biochemistry & Molecular Biology, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Jan K Rainey
- Department of Biochemistry & Molecular Biology, Dalhousie University, Halifax, Nova Scotia, Canada
- Department of Chemistry, Dalhousie University, Halifax, Nova Scotia, Canada
| |
Collapse
|
18
|
Visualization of ligand-induced dopamine D 2S and D 2L receptor internalization by TIRF microscopy. Sci Rep 2017; 7:10894. [PMID: 28883522 PMCID: PMC5589927 DOI: 10.1038/s41598-017-11436-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2017] [Accepted: 08/23/2017] [Indexed: 01/11/2023] Open
Abstract
G protein-coupled receptors (GPCRs), including the dopamine receptors, represent a group of important pharmacological targets. Upon agonist binding, GPCRs frequently undergo internalization, a process that is known to attenuate functional responses upon prolonged exposure to agonists. In this study, internalization was visualized by means of total internal reflection fluorescence (TIRF) microscopy at a level of discrete single events near the plasma membrane with high spatial resolution. A novel method has been developed to determine the relative extent of internalized fluorescent receptor-ligand complexes by comparative fluorescence quantification in living CHO cells. The procedure entails treatment with the reducing agent sodium borohydride, which converts cyanine-based fluorescent ligands on the membrane surface to a long-lived reduced form. Because the highly polar reducing agent is not able to pass the cell membrane, the fluorescent receptor-ligand complexes located in internalized compartments remain fluorescent under TIRF illumination. We applied the method to investigate differences of the short (D2S) and the long (D2L) isoforms of dopamine D2 receptors in their ability to undergo agonist-induced internalization.
Collapse
|
19
|
Wacker D, Stevens RC, Roth BL. How Ligands Illuminate GPCR Molecular Pharmacology. Cell 2017; 170:414-427. [PMID: 28753422 DOI: 10.1016/j.cell.2017.07.009] [Citation(s) in RCA: 366] [Impact Index Per Article: 52.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2017] [Revised: 06/13/2017] [Accepted: 07/11/2017] [Indexed: 12/31/2022]
Abstract
G protein-coupled receptors (GPCRs), which are modulated by a variety of endogenous and synthetic ligands, represent the largest family of druggable targets in the human genome. Recent structural and molecular studies have both transformed and expanded classical concepts of receptor pharmacology and have begun to illuminate the distinct mechanisms by which structurally, chemically, and functionally diverse ligands modulate GPCR function. These molecular insights into ligand engagement and action have enabled new computational methods and accelerated the discovery of novel ligands and tool compounds, especially for understudied and orphan GPCRs. These advances promise to streamline the development of GPCR-targeted medications.
Collapse
Affiliation(s)
- Daniel Wacker
- Department of Pharmacology and Division of Chemical Biology and Medicinal Chemistry, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC 27514, USA
| | - Raymond C Stevens
- Departments of Biological Sciences and Chemistry, Bridge Institute, University of Southern California, Los Angeles, CA 90089, USA
| | - Bryan L Roth
- Department of Pharmacology and Division of Chemical Biology and Medicinal Chemistry, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC 27514, USA.
| |
Collapse
|
20
|
Noha SM, Schmidhammer H, Spetea M. Molecular Docking, Molecular Dynamics, and Structure-Activity Relationship Explorations of 14-Oxygenated N-Methylmorphinan-6-ones as Potent μ-Opioid Receptor Agonists. ACS Chem Neurosci 2017; 8:1327-1337. [PMID: 28125215 PMCID: PMC5481819 DOI: 10.1021/acschemneuro.6b00460] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
![]()
Among opioids, morphinans
are of major importance as the most effective
analgesic drugs acting primarily via μ-opioid receptor (μ-OR)
activation. Our long-standing efforts in the field of opioid analgesics
from the class of morphinans led to N-methylmorphinan-6-ones
differently substituted at positions 5 and 14 as μ-OR agonists
inducing potent analgesia and fewer undesirable effects. Herein we
present the first thorough molecular modeling study and structure–activity
relationship (SAR) explorations aided by docking and molecular dynamics
(MD) simulations of 14-oxygenated N-methylmorphinan-6-ones
to gain insights into their mode of binding to the μ-OR and
interaction mechanisms. The structure of activated μ-OR provides
an essential model for how ligand/μ-OR binding is encoded within
small chemical differences in otherwise structurally similar morphinans.
We reveal important molecular interactions that these μ-agonists
share and distinguish them. The molecular docking outcomes indicate
the crucial role of the relative orientation of the ligand in the
μ-OR binding site, influencing the propensity of critical non-covalent
interactions that are required to facilitate ligand/μ-OR interactions
and receptor activation. The MD simulations point out minor differences
in the tendency to form hydrogen bonds by the 4,5α-epoxy group,
along with the tendency to affect the 3–7 lock switch. The
emerged SARs reveal the subtle interplay between the substituents
at positions 5 and 14 in the morphinan scaffold by enabling the identification
of key structural elements that determine the distinct pharmacological
profiles. This study provides a significant structural basis for understanding
ligand binding and μ-OR activation by the 14-oxygenated N-methylmorphinan-6-ones, which should be useful for guiding
drug design.
Collapse
Affiliation(s)
- Stefan M. Noha
- Computer-Aided
Molecular Design (CAMD) Group, Department of Pharmaceutical Chemistry,
Institute of Pharmacy and Center for Molecular Biosciences Innsbruck
(CMBI), University of Innsbruck, Innrain 80-82, 6020 Innsbruck, Austria
| | - Helmut Schmidhammer
- Opioid
Research Group, Department of Pharmaceutical Chemistry, Institute
of Pharmacy and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innrain 80-82, 6020 Innsbruck, Austria
| | - Mariana Spetea
- Opioid
Research Group, Department of Pharmaceutical Chemistry, Institute
of Pharmacy and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innrain 80-82, 6020 Innsbruck, Austria
| |
Collapse
|
21
|
Sleno R, Devost D, Pétrin D, Zhang A, Bourque K, Shinjo Y, Aoki J, Inoue A, Hébert TE. Conformational biosensors reveal allosteric interactions between heterodimeric AT1 angiotensin and prostaglandin F2α receptors. J Biol Chem 2017; 292:12139-12152. [PMID: 28584054 DOI: 10.1074/jbc.m117.793877] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2017] [Revised: 05/31/2017] [Indexed: 11/06/2022] Open
Abstract
G protein-coupled receptors (GPCRs) are conformationally dynamic proteins transmitting ligand-encoded signals in multiple ways. This transmission is highly complex and achieved through induction of distinct GPCR conformations, which preferentially drive specific receptor-mediated signaling events. This conformational capacity can be further enlarged via allosteric effects between dimers, warranting further study of these effects. Using GPCR conformation-sensitive biosensors, we investigated allosterically induced conformational changes in the recently reported F prostanoid (FP)/angiotensin II type 1 receptor (AT1R) heterodimer. Ligand occupancy of the AT1R induced distinct conformational changes in FP compared with those driven by PGF2α in bioluminescence resonance energy transfer (BRET)-based FP biosensors engineered with Renilla luciferase (RLuc) as an energy donor in the C-tail and fluorescein arsenical hairpin binder (FlAsH)-labeled acceptors at different positions in the intracellular loops. We also found that this allosteric communication is mediated through Gαq and may also involve proximal (phospholipase C) but not distal (protein kinase C) signaling partners. Interestingly, β-arrestin-biased AT1R agonists could also transmit a Gαq-dependent signal to FP without activation of downstream Gαq signaling. This transmission of information was specific to the AT1R/FP complex, as activation of Gαq by the oxytocin receptor did not recapitulate the same phenomenon. Finally, information flow was asymmetric in the sense that FP activation had negligible effects on AT1R-based conformational biosensors. The identification of partner-induced GPCR conformations may help identify novel allosteric effects when investigating multiprotein receptor signaling complexes.
Collapse
Affiliation(s)
- Rory Sleno
- Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec H3G 1Y6, Canada
| | - Dominic Devost
- Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec H3G 1Y6, Canada
| | - Darlaine Pétrin
- Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec H3G 1Y6, Canada
| | - Alice Zhang
- Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec H3G 1Y6, Canada
| | - Kyla Bourque
- Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec H3G 1Y6, Canada
| | - Yuji Shinjo
- Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Miyagi 980-8578, Japan
| | - Junken Aoki
- Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Miyagi 980-8578, Japan; Japan Agency for Medical Research and Development, Core Research for Evolutional Science and Technology (AMED-CREST), Chiyoda-ku, Tokyo 100-0004, Japan
| | - Asuka Inoue
- Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Miyagi 980-8578, Japan; Japan Science and Technology Agency (JST), Precursory Research for Embryonic Science and Technology (PRESTO), Kawaguchi, Saitama 332-0012, Japan
| | - Terence E Hébert
- Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec H3G 1Y6, Canada.
| |
Collapse
|
22
|
Tuning the allosteric regulation of artificial muscarinic and dopaminergic ligand-gated potassium channels by protein engineering of G protein-coupled receptors. Sci Rep 2017; 7:41154. [PMID: 28145461 PMCID: PMC5286527 DOI: 10.1038/srep41154] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2016] [Accepted: 12/14/2016] [Indexed: 12/15/2022] Open
Abstract
Ligand-gated ion channels enable intercellular transmission of action potential through synapses by transducing biochemical messengers into electrical signal. We designed artificial ligand-gated ion channels by coupling G protein-coupled receptors to the Kir6.2 potassium channel. These artificial channels called ion channel-coupled receptors offer complementary properties to natural channels by extending the repertoire of ligands to those recognized by the fused receptors, by generating more sustained signals and by conferring potassium selectivity. The first artificial channels based on the muscarinic M2 and the dopaminergic D2L receptors were opened and closed by acetylcholine and dopamine, respectively. We find here that this opposite regulation of the gating is linked to the length of the receptor C-termini, and that C-terminus engineering can precisely control the extent and direction of ligand gating. These findings establish the design rules to produce customized ligand-gated channels for synthetic biology applications.
Collapse
|
23
|
Legler DF, Matti C, Laufer JM, Jakobs BD, Purvanov V, Uetz-von Allmen E, Thelen M. Modulation of Chemokine Receptor Function by Cholesterol: New Prospects for Pharmacological Intervention. Mol Pharmacol 2017; 91:331-338. [PMID: 28082305 DOI: 10.1124/mol.116.107151] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2016] [Accepted: 01/09/2017] [Indexed: 12/12/2022] Open
Abstract
Chemokine receptors are seven transmembrane-domain receptors belonging to class A of G-protein-coupled receptors (GPCRs). The receptors together with their chemokine ligands constitute the chemokine system, which is essential for directing cell migration and plays a crucial role in a variety of physiologic and pathologic processes. Given the importance of orchestrating cell migration, it is vital that chemokine receptor signaling is tightly regulated to ensure appropriate responses. Recent studies highlight a key role for cholesterol in modulating chemokine receptor activities. The steroid influences the spatial organization of GPCRs within the membrane bilayer, and consequently can tune chemokine receptor signaling. The effects of cholesterol on the organization and function of chemokine receptors and GPCRs in general include direct and indirect effects (Fig. 1). Here, we review how cholesterol and some key metabolites modulate functions of the chemokine system in multiple ways. We emphasize the role of cholesterol in chemokine receptor oligomerization, thereby promoting the formation of a signaling hub enabling integration of distinct signaling pathways at the receptor-membrane interface. Moreover, we discuss the role of cholesterol in stabilizing particular receptor conformations and its consequence for chemokine binding. Finally, we highlight how cholesterol accumulation, its deprivation, or cholesterol metabolites contribute to modulating cell orchestration during inflammation, induction of an adaptive immune response, as well as to dampening an anti-tumor immune response.
Collapse
Affiliation(s)
- Daniel F Legler
- Biotechnology Institute Thurgau at the University of Konstanz, Kreuzlingen, Switzerland (D.F.L., C.M., J.M.L., B.D.J, V.P., E.U.A.); Konstanz Research School Chemical Biology, University of Konstanz, Germany (D.F.L., C.M., J.M.L); and Institute for Research in Biomedicine, Università della Svizzera italiana, Bellinzona, Switzerland (M.T.)
| | - Christoph Matti
- Biotechnology Institute Thurgau at the University of Konstanz, Kreuzlingen, Switzerland (D.F.L., C.M., J.M.L., B.D.J, V.P., E.U.A.); Konstanz Research School Chemical Biology, University of Konstanz, Germany (D.F.L., C.M., J.M.L); and Institute for Research in Biomedicine, Università della Svizzera italiana, Bellinzona, Switzerland (M.T.)
| | - Julia M Laufer
- Biotechnology Institute Thurgau at the University of Konstanz, Kreuzlingen, Switzerland (D.F.L., C.M., J.M.L., B.D.J, V.P., E.U.A.); Konstanz Research School Chemical Biology, University of Konstanz, Germany (D.F.L., C.M., J.M.L); and Institute for Research in Biomedicine, Università della Svizzera italiana, Bellinzona, Switzerland (M.T.)
| | - Barbara D Jakobs
- Biotechnology Institute Thurgau at the University of Konstanz, Kreuzlingen, Switzerland (D.F.L., C.M., J.M.L., B.D.J, V.P., E.U.A.); Konstanz Research School Chemical Biology, University of Konstanz, Germany (D.F.L., C.M., J.M.L); and Institute for Research in Biomedicine, Università della Svizzera italiana, Bellinzona, Switzerland (M.T.)
| | - Vladimir Purvanov
- Biotechnology Institute Thurgau at the University of Konstanz, Kreuzlingen, Switzerland (D.F.L., C.M., J.M.L., B.D.J, V.P., E.U.A.); Konstanz Research School Chemical Biology, University of Konstanz, Germany (D.F.L., C.M., J.M.L); and Institute for Research in Biomedicine, Università della Svizzera italiana, Bellinzona, Switzerland (M.T.)
| | - Edith Uetz-von Allmen
- Biotechnology Institute Thurgau at the University of Konstanz, Kreuzlingen, Switzerland (D.F.L., C.M., J.M.L., B.D.J, V.P., E.U.A.); Konstanz Research School Chemical Biology, University of Konstanz, Germany (D.F.L., C.M., J.M.L); and Institute for Research in Biomedicine, Università della Svizzera italiana, Bellinzona, Switzerland (M.T.)
| | - Marcus Thelen
- Biotechnology Institute Thurgau at the University of Konstanz, Kreuzlingen, Switzerland (D.F.L., C.M., J.M.L., B.D.J, V.P., E.U.A.); Konstanz Research School Chemical Biology, University of Konstanz, Germany (D.F.L., C.M., J.M.L); and Institute for Research in Biomedicine, Università della Svizzera italiana, Bellinzona, Switzerland (M.T.)
| |
Collapse
|
24
|
Flanagan CA, Manilall A. Gonadotropin-Releasing Hormone (GnRH) Receptor Structure and GnRH Binding. Front Endocrinol (Lausanne) 2017; 8:274. [PMID: 29123501 PMCID: PMC5662886 DOI: 10.3389/fendo.2017.00274] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/08/2017] [Accepted: 09/28/2017] [Indexed: 12/22/2022] Open
Abstract
Gonadotropin-releasing hormone (GnRH) regulates reproduction. The human GnRH receptor lacks a cytoplasmic carboxy-terminal tail but has amino acid sequence motifs characteristic of rhodopsin-like, class A, G protein-coupled receptors (GPCRs). This review will consider how recent descriptions of X-ray crystallographic structures of GPCRs in inactive and active conformations may contribute to understanding GnRH receptor structure, mechanism of activation and ligand binding. The structures confirmed that ligands bind to variable extracellular surfaces, whereas the seven membrane-spanning α-helices convey the activation signal to the cytoplasmic receptor surface, which binds and activates heterotrimeric G proteins. Forty non-covalent interactions that bridge topologically equivalent residues in different transmembrane (TM) helices are conserved in class A GPCR structures, regardless of activation state. Conformation-independent interhelical contacts account for a conserved receptor protein structure and their importance in the GnRH receptor structure is supported by decreased expression of receptors with mutations of residues in the network. Many of the GnRH receptor mutations associated with congenital hypogonadotropic hypogonadism, including the Glu2.53(90) Lys mutation, involve amino acids that constitute the conserved network. Half of the ~250 intramolecular interactions in GPCRs differ between inactive and active structures. Conformation-specific interhelical contacts depend on amino acids changing partners during activation. Conserved inactive conformation-specific contacts prevent receptor activation by stabilizing proximity of TM helices 3 and 6 and a closed G protein-binding site. Mutations of GnRH receptor residues involved in these interactions, such as Arg3.50(139) of the DRY/S motif or Tyr7.53(323) of the N/DPxxY motif, increase or decrease receptor expression and efficiency of receptor coupling to G protein signaling, consistent with the native residues stabilizing the inactive GnRH receptor structure. Active conformation-specific interhelical contacts stabilize an open G protein-binding site. Progress in defining the GnRH-binding site has recently slowed, with evidence that Tyr6.58(290) contacts Tyr5 of GnRH, whereas other residues affect recognition of Trp3 and Gly10NH2. The surprisingly consistent observations that GnRH receptor mutations that disrupt GnRH binding have less effect on "conformationally constrained" GnRH peptides may now be explained by crystal structures of agonist-bound peptide receptors. Analysis of GPCR structures provides insight into GnRH receptor function.
Collapse
Affiliation(s)
- Colleen A. Flanagan
- Faculty of Health Sciences, School of Physiology, University of the Witwatersrand, Johannesburg, South Africa
- *Correspondence: Colleen A. Flanagan,
| | - Ashmeetha Manilall
- Faculty of Health Sciences, School of Physiology, University of the Witwatersrand, Johannesburg, South Africa
| |
Collapse
|
25
|
Vázquez-Prado J, Bracho-Valdés I, Cervantes-Villagrana RD, Reyes-Cruz G. Gβγ Pathways in Cell Polarity and Migration Linked to Oncogenic GPCR Signaling: Potential Relevance in Tumor Microenvironment. Mol Pharmacol 2016; 90:573-586. [DOI: 10.1124/mol.116.105338] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2016] [Accepted: 09/14/2016] [Indexed: 12/16/2022] Open
|