1
|
Zhang MY, Ao JY, Liu N, Chen T, Lu SY. Exploring the constitutive activation mechanism of the class A orphan GPR20. Acta Pharmacol Sin 2024:10.1038/s41401-024-01385-7. [PMID: 39256608 DOI: 10.1038/s41401-024-01385-7] [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: 07/11/2024] [Accepted: 08/22/2024] [Indexed: 09/12/2024] Open
Abstract
GPR20, an orphan G protein-coupled receptor (GPCR), shows significant expression in intestinal tissue and represents a potential therapeutic target to treat gastrointestinal stromal tumors. GPR20 performs high constitutive activity when coupling with Gi. Despite the pharmacological importance of GPCR constitutive activation, determining the mechanism has long remained unclear. In this study, we explored the constitutive activation mechanism of GPR20 through large-scale unbiased molecular dynamics simulations. Our results unveil the allosteric nature of constitutively activated GPCR signal transduction involving extracellular and intracellular domains. Moreover, the constitutively active state of the GPR20 requires both the N-terminal cap and Gi protein. The N-terminal cap of GPR20 functions like an agonist and mediates long-range activated conformational shift. Together with the previous study, this study enhances our knowledge of the self-activation mechanism of the orphan receptor, facilitates the drug discovery efforts that target GPR20.
Collapse
Affiliation(s)
- Ming-Yang Zhang
- Key Laboratory of Protection, Development and Utilization of Medicinal Resources in Liupanshan Area, Ministry of Education, Peptide & Protein Drug Research Center, School of Pharmacy, Ningxia Medical University, Yinchuan, 750004, China
- Medicinal Chemistry and Bioinformatics Center, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China
| | - Jian-Yang Ao
- Department of Hepatobiliary and Pancreatic Surgery, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, 200120, China
- Institute of Hepatobiliary and Pancreatic Surgery, Tongji University School of Medicine, Shanghai, 200120, China
| | - Ning Liu
- Key Laboratory of Protection, Development and Utilization of Medicinal Resources in Liupanshan Area, Ministry of Education, Peptide & Protein Drug Research Center, School of Pharmacy, Ningxia Medical University, Yinchuan, 750004, China
| | - Ting Chen
- Department of Cardiology, Changzheng Hospital, Affiliated to Naval Medical University, Shanghai, 200003, China.
| | - Shao-Yong Lu
- Key Laboratory of Protection, Development and Utilization of Medicinal Resources in Liupanshan Area, Ministry of Education, Peptide & Protein Drug Research Center, School of Pharmacy, Ningxia Medical University, Yinchuan, 750004, China.
- Medicinal Chemistry and Bioinformatics Center, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China.
| |
Collapse
|
2
|
Li C, Xu Y, Su W, He X, Li J, Li X, Xu HE, Yin W. Structural insights into ligand recognition, selectivity, and activation of bombesin receptor subtype-3. Cell Rep 2024; 43:114511. [PMID: 39024101 DOI: 10.1016/j.celrep.2024.114511] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2024] [Revised: 05/16/2024] [Accepted: 06/28/2024] [Indexed: 07/20/2024] Open
Abstract
Bombesin receptor subtype-3 (BRS3) is an important orphan G protein-coupled receptor that regulates energy homeostasis and insulin secretion. As a member of the bombesin receptor (BnR) family, the lack of known endogenous ligands and high-resolution structure has hindered the understanding of BRS3 signaling and function. We present two cryogenic electron microscopy (cryo-EM) structures of BRS3 in complex with the heterotrimeric Gq protein in its active states: one bound to the pan-BnR agonist BA1 and the other bound to the synthetic BRS3-specific agonist MK-5046. These structures reveal the architecture of the orthosteric ligand pocket underpinning molecular recognition and provide insights into the structural basis for BRS3's selectivity and low affinity for bombesin peptides. Examination of conserved micro-switches suggests a shared activation mechanism among BnRs. Our findings shed light on BRS3's ligand selectivity and signaling mechanisms, paving the way for exploring its therapeutic potential for diabetes, obesity, and related metabolic disorders.
Collapse
Affiliation(s)
- Changyao Li
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China; School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China; Lingang Laboratory, Shanghai 200031, China
| | - Youwei Xu
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Wenxin Su
- Guangzhou University of Chinese Medicine, Zhongshan Institute for Drug Discovery, Guangdong 510000, China; Zhongshan Institute for Drug Discovery, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Guangdong 528400, China
| | - Xinheng He
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jingru Li
- School of Chinese Materia Medica, Nanjing University of Chinese Medicine, Nanjing 210023, China
| | - Xinzhu Li
- School of Chinese Materia Medica, Nanjing University of Chinese Medicine, Nanjing 210023, China
| | - H Eric Xu
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China; School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China; Lingang Laboratory, Shanghai 200031, China; University of Chinese Academy of Sciences, Beijing 100049, China; School of Chinese Materia Medica, Nanjing University of Chinese Medicine, Nanjing 210023, China.
| | - Wanchao Yin
- Zhongshan Institute for Drug Discovery, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Guangdong 528400, China; State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China; Guangzhou University of Chinese Medicine, Zhongshan Institute for Drug Discovery, Guangdong 510000, China; University of Chinese Academy of Sciences, Beijing 100049, China.
| |
Collapse
|
3
|
Russell I, Zhang X, Bumbak F, McNeill SM, Josephs TM, Leeming MG, Christopoulos G, Venugopal H, Flocco MM, Sexton PM, Wootten D, Belousoff MJ. Lipid-Dependent Activation of the Orphan G Protein-Coupled Receptor, GPR3. Biochemistry 2024; 63:625-631. [PMID: 38376112 PMCID: PMC10919283 DOI: 10.1021/acs.biochem.3c00647] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2023] [Revised: 02/02/2024] [Accepted: 02/12/2024] [Indexed: 02/21/2024]
Abstract
The class A orphan G protein-coupled receptor (GPCR), GPR3, has been implicated in a variety of conditions, including Alzheimer's and premature ovarian failure. GPR3 constitutively couples with Gαs, resulting in the production of cAMP in cells. While tool compounds and several putative endogenous ligands have emerged for the receptor, its endogenous ligand, if it exists, remains a mystery. As novel potential drug targets, the structures of orphan GPCRs have been of increasing interest, revealing distinct modes of activation, including autoactivation, presence of constitutively activating mutations, or via cryptic ligands. Here, we present a cryo-electron microscopy (cryo-EM) structure of the orphan GPCR, GPR3 in complex with DNGαs and Gβ1γ2. The structure revealed clear density for a lipid-like ligand that bound within an extended hydrophobic groove, suggesting that the observed "constitutive activity" was likely due to activation via a lipid that may be ubiquitously present. Analysis of conformational variance within the cryo-EM data set revealed twisting motions of the GPR3 transmembrane helices that appeared coordinated with changes in the lipid-like density. We propose a mechanism for the binding of a lipid to its putative orthosteric binding pocket linked to the GPR3 dynamics.
Collapse
Affiliation(s)
- Isabella
C. Russell
- Drug
Discovery Biology Theme, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville 3052, Victoria Australia
- Australian
Research Council Centre for Cryo-Electron Microscopy of Membrane Proteins,
Monash Institute of Pharmaceutical Sciences, Monash University, Parkville 3052, Victoria Australia
| | - Xin Zhang
- Drug
Discovery Biology Theme, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville 3052, Victoria Australia
- Australian
Research Council Centre for Cryo-Electron Microscopy of Membrane Proteins,
Monash Institute of Pharmaceutical Sciences, Monash University, Parkville 3052, Victoria Australia
| | - Fabian Bumbak
- Drug
Discovery Biology Theme, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville 3052, Victoria Australia
- Australian
Research Council Centre for Cryo-Electron Microscopy of Membrane Proteins,
Monash Institute of Pharmaceutical Sciences, Monash University, Parkville 3052, Victoria Australia
| | - Samantha M. McNeill
- Drug
Discovery Biology Theme, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville 3052, Victoria Australia
| | - Tracy M. Josephs
- Drug
Discovery Biology Theme, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville 3052, Victoria Australia
- Australian
Research Council Centre for Cryo-Electron Microscopy of Membrane Proteins,
Monash Institute of Pharmaceutical Sciences, Monash University, Parkville 3052, Victoria Australia
| | - Michael G. Leeming
- Bio21
Molecular Science & Biotechnology Institute, Melbourne Mass Spectrometry
and Proteomics Facility, The University
of Melbourne, Melbourne, VIC 3052, Australia
| | - George Christopoulos
- Drug
Discovery Biology Theme, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville 3052, Victoria Australia
| | - Hariprasad Venugopal
- Ramaciotti
Centre for Cryo Electron Microscopy, Monash University, Clayton 3800, Victoria Australia
| | - Maria M. Flocco
- Mechanistic
and Structural Biology, Discovery Sciences, BioPharmaceuticals R&D, AstraZeneca, Cambridge CB20AA, United Kingdom
| | - Patrick M. Sexton
- Drug
Discovery Biology Theme, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville 3052, Victoria Australia
- Australian
Research Council Centre for Cryo-Electron Microscopy of Membrane Proteins,
Monash Institute of Pharmaceutical Sciences, Monash University, Parkville 3052, Victoria Australia
| | - Denise Wootten
- Drug
Discovery Biology Theme, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville 3052, Victoria Australia
- Australian
Research Council Centre for Cryo-Electron Microscopy of Membrane Proteins,
Monash Institute of Pharmaceutical Sciences, Monash University, Parkville 3052, Victoria Australia
| | - Matthew J. Belousoff
- Drug
Discovery Biology Theme, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville 3052, Victoria Australia
- Australian
Research Council Centre for Cryo-Electron Microscopy of Membrane Proteins,
Monash Institute of Pharmaceutical Sciences, Monash University, Parkville 3052, Victoria Australia
| |
Collapse
|
4
|
Scharf MM, Humphrys LJ, Berndt S, Di Pizio A, Lehmann J, Liebscher I, Nicoli A, Niv MY, Peri L, Schihada H, Schulte G. The dark sides of the GPCR tree - research progress on understudied GPCRs. Br J Pharmacol 2024. [PMID: 38339984 DOI: 10.1111/bph.16325] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2023] [Revised: 11/24/2023] [Accepted: 01/08/2024] [Indexed: 02/12/2024] Open
Abstract
A large portion of the human GPCRome is still in the dark and understudied, consisting even of entire subfamilies of GPCRs such as odorant receptors, class A and C orphans, adhesion GPCRs, Frizzleds and taste receptors. However, it is undeniable that these GPCRs bring an untapped therapeutic potential that should be explored further. Open questions on these GPCRs span diverse topics such as deorphanisation, the development of tool compounds and tools for studying these GPCRs, as well as understanding basic signalling mechanisms. This review gives an overview of the current state of knowledge for each of the diverse subfamilies of understudied receptors regarding their physiological relevance, molecular mechanisms, endogenous ligands and pharmacological tools. Furthermore, it identifies some of the largest knowledge gaps that should be addressed in the foreseeable future and lists some general strategies that might be helpful in this process.
Collapse
Affiliation(s)
- Magdalena M Scharf
- Karolinska Institutet, Dept. Physiology & Pharmacology, Sec. Receptor Biology & Signaling, Stockholm, Sweden
| | - Laura J Humphrys
- Institute of Pharmacy, University of Regensburg, Regensburg, Germany
| | - Sandra Berndt
- Rudolf Schönheimer Institute for Biochemistry, Molecular Biochemistry, University of Leipzig, Leipzig, Germany
| | - Antonella Di Pizio
- Leibniz Institute for Food Systems Biology at the Technical University of Munich, Freising, Germany
- Chemoinformatics and Protein Modelling, Department of Molecular Life Science, School of Life Science, Technical University of Munich, Freising, Germany
| | - Juliane Lehmann
- Rudolf Schönheimer Institute for Biochemistry, Molecular Biochemistry, University of Leipzig, Leipzig, Germany
| | - Ines Liebscher
- Rudolf Schönheimer Institute for Biochemistry, Molecular Biochemistry, University of Leipzig, Leipzig, Germany
| | - Alessandro Nicoli
- Leibniz Institute for Food Systems Biology at the Technical University of Munich, Freising, Germany
- Chemoinformatics and Protein Modelling, Department of Molecular Life Science, School of Life Science, Technical University of Munich, Freising, Germany
| | - Masha Y Niv
- The Institute of Biochemistry, Food Science and Nutrition, Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, Israel
| | - Lior Peri
- The Institute of Biochemistry, Food Science and Nutrition, Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, Israel
| | - Hannes Schihada
- Institute of Pharmaceutical Chemistry, Philipps-University Marburg, Marburg, Germany
| | - Gunnar Schulte
- Karolinska Institutet, Dept. Physiology & Pharmacology, Sec. Receptor Biology & Signaling, Stockholm, Sweden
| |
Collapse
|
5
|
Bresinsky M, Shahraki A, Kolb P, Pockes S, Schihada H. Development of Fluorescent AF64394 Analogues Enables Real-Time Binding Studies for the Orphan Class A GPCR GPR3. J Med Chem 2023; 66:15025-15041. [PMID: 37907069 PMCID: PMC10641823 DOI: 10.1021/acs.jmedchem.3c01707] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Revised: 10/16/2023] [Accepted: 10/18/2023] [Indexed: 11/02/2023]
Abstract
The orphan G protein-coupled receptor (oGPCR) GPR3 represents a potential drug target for the treatment of Alzheimer's disease and metabolic disorders. However, the limited toolbox of pharmacological assays hampers the development of advanced ligands. Here, we developed a signaling pathway-independent readout of compound-GPR3 interaction. Starting from computational binding pose predictions of the most potent GPR3 ligand, we designed a series of fluorescent AF64394 analogues and assessed their suitability for BRET-based binding studies. The most potent ligand, 45 (UR-MB-355), bound to GPR3 and closely related receptors, GPR6 and GPR12, with similar submicromolar affinities. Furthermore, we found that 45 engages GPR3 in a distinct mode compared to AF64394, and coincubation studies with the GPR3 agonist diphenyleneiodonium chloride revealed allosteric modulation of 45 binding. These insights provide new cues for the pharmacological manipulation of GPR3 activity. This novel binding assay will foster the development of future drugs acting through these pharmacologically attractive oGPCRs.
Collapse
Affiliation(s)
- Merlin Bresinsky
- Institute
of Pharmacy, University of Regensburg, Universitätsstraße 31, 93053 Regensburg, Germany
| | - Aida Shahraki
- Department
of Pharmaceutical Chemistry, University
of Marburg, Marbacher Weg 8, 35032 Marburg, Germany
| | - Peter Kolb
- Department
of Pharmaceutical Chemistry, University
of Marburg, Marbacher Weg 8, 35032 Marburg, Germany
| | - Steffen Pockes
- Institute
of Pharmacy, University of Regensburg, Universitätsstraße 31, 93053 Regensburg, Germany
- Department
of Medicinal Chemistry, Institute for Therapeutics Discovery and Development, University of Minnesota, Minneapolis, Minnesota 55414, United States
| | - Hannes Schihada
- Department
of Pharmaceutical Chemistry, University
of Marburg, Marbacher Weg 8, 35032 Marburg, Germany
| |
Collapse
|
6
|
Wu Z, Han Z, Tao L, Sun X, Su J, Hu J, Li C. Dynamic Insights into the Self-Activation Pathway and Allosteric Regulation of the Orphan G-Protein-Coupled Receptor GPR52. J Chem Inf Model 2023; 63:5847-5862. [PMID: 37651308 DOI: 10.1021/acs.jcim.3c00672] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/02/2023]
Abstract
Within over 800 members of G-protein-coupled receptors, there are numerous orphan receptors whose endogenous ligands are largely unknown, providing many opportunities for novel drug discovery. However, the lack of an in-depth understanding of the intrinsic working mechanism for orphan receptors severely limits the related rational drug design. The G-protein-coupled receptor 52 (GPR52) is a unique orphan receptor that constitutively increases cellular 5'-cyclic adenosine monophosphate (cAMP) levels without binding any exogenous agonists and has been identified as a promising therapeutic target for central nervous system disorders. Although recent structural biology studies have provided snapshots of both active and inactive states of GPR52, the mechanism of the conformational transition between these states remains unclear. Here, an acceptable self-activation pathway for GPR52 was proposed through 6 μs Gaussian accelerated molecular dynamics (GaMD) simulations, in which the receptor spontaneously transitions from the active state to that matching the inactive crystal structure. According to the three intermediate states of the receptor obtained by constructing a reweighted potential of mean force, how the allosteric regulation occurs between the extracellular orthosteric binding pocket and the intracellular G-protein-binding site is revealed. Combined with the independent gradient model, several important microswitch residues and the allosteric communication pathway that directly links the two regions are both identified. Transfer entropy calculations not only reveal the complex allosteric signaling within GPR52 but also confirm the unique role of ECL2 in allosteric regulation, which is mutually validated with the results of GaMD simulations. Overall, this work elucidates the allosteric mechanism of GPR52 at the atomic level, providing the most detailed information to date on the self-activation of the orphan receptor.
Collapse
Affiliation(s)
- Zhixiang Wu
- Faculty of Environmental and Life Sciences, Beijing University of Technology, Beijing 100124, China
| | - Zhongjie Han
- Faculty of Environmental and Life Sciences, Beijing University of Technology, Beijing 100124, China
| | - Lianci Tao
- Faculty of Environmental and Life Sciences, Beijing University of Technology, Beijing 100124, China
| | - Xiaohan Sun
- Faculty of Environmental and Life Sciences, Beijing University of Technology, Beijing 100124, China
| | - Jingjie Su
- Faculty of Environmental and Life Sciences, Beijing University of Technology, Beijing 100124, China
| | - Jianping Hu
- Key Laboratory of Medicinal and Edible Plants Resources Development of Sichuan Education Department, School of Pharmacy, Chengdu University, Chengdu 610106, China
| | - Chunhua Li
- Faculty of Environmental and Life Sciences, Beijing University of Technology, Beijing 100124, China
| |
Collapse
|
7
|
Lees JA, Dias JM, Rajamohan F, Fortin JP, O'Connor R, Kong JX, Hughes EAG, Fisher EL, Tuttle JB, Lovett G, Kormos BL, Unwalla RJ, Zhang L, Dechert Schmitt AM, Zhou D, Moran M, Stevens KA, Fennell KF, Varghese AE, Maxwell A, Cote EE, Zhang Y, Han S. An inverse agonist of orphan receptor GPR61 acts by a G protein-competitive allosteric mechanism. Nat Commun 2023; 14:5938. [PMID: 37741852 PMCID: PMC10517971 DOI: 10.1038/s41467-023-41646-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Accepted: 09/11/2023] [Indexed: 09/25/2023] Open
Abstract
GPR61 is an orphan GPCR related to biogenic amine receptors. Its association with phenotypes relating to appetite makes it of interest as a druggable target to treat disorders of metabolism and body weight, such as obesity and cachexia. To date, the lack of structural information or a known biological ligand or tool compound has hindered comprehensive efforts to study GPR61 structure and function. Here, we report a structural characterization of GPR61, in both its active-like complex with heterotrimeric G protein and in its inactive state. Moreover, we report the discovery of a potent and selective small-molecule inverse agonist against GPR61 and structural elucidation of its allosteric binding site and mode of action. These findings offer mechanistic insights into an orphan GPCR while providing both a structural framework and tool compound to support further studies of GPR61 function and modulation.
Collapse
Affiliation(s)
- Joshua A Lees
- Discovery Sciences, Medicine Design, Pfizer Inc., Groton, CT, USA
| | - João M Dias
- Discovery Sciences, Medicine Design, Pfizer Inc., Groton, CT, USA
| | | | | | - Rebecca O'Connor
- Discovery Sciences, Medicine Design, Pfizer Inc., Groton, CT, USA
| | - Jimmy X Kong
- Internal Medicine Research Unit, Pfizer Inc., Cambridge, MA, USA
| | - Emily A G Hughes
- Internal Medicine Research Unit, Pfizer Inc., Cambridge, MA, USA
| | - Ethan L Fisher
- Internal Medicine, Medicine Design, Pfizer Inc., Groton, CT, USA
| | - Jamison B Tuttle
- Internal Medicine, Medicine Design, Pfizer Inc., Cambridge, MA, USA
| | - Gabrielle Lovett
- Internal Medicine, Medicine Design, Pfizer Inc., Cambridge, MA, USA
| | - Bethany L Kormos
- Internal Medicine, Medicine Design, Pfizer Inc., Cambridge, MA, USA
| | | | - Lei Zhang
- Internal Medicine, Medicine Design, Pfizer Inc., Cambridge, MA, USA
| | | | - Dahui Zhou
- Internal Medicine, Medicine Design, Pfizer Inc., Groton, CT, USA
| | - Michael Moran
- Internal Medicine, Medicine Design, Pfizer Inc., Groton, CT, USA
| | | | | | | | - Andrew Maxwell
- Discovery Sciences, Medicine Design, Pfizer Inc., Groton, CT, USA
| | - Emmaline E Cote
- Discovery Sciences, Medicine Design, Pfizer Inc., Groton, CT, USA
| | - Yuan Zhang
- Internal Medicine, Medicine Design, Pfizer Inc., Cambridge, MA, USA
| | - Seungil Han
- Discovery Sciences, Medicine Design, Pfizer Inc., Groton, CT, USA.
| |
Collapse
|
8
|
Nie Y, Qiu Z, Chen S, Chen Z, Song X, Ma Y, Huang N, Cyster JG, Zheng S. Specific binding of GPR174 by endogenous lysophosphatidylserine leads to high constitutive G s signaling. Nat Commun 2023; 14:5901. [PMID: 37737235 PMCID: PMC10516915 DOI: 10.1038/s41467-023-41654-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2023] [Accepted: 09/13/2023] [Indexed: 09/23/2023] Open
Abstract
Many orphan G protein-coupled receptors (GPCRs) remain understudied because their endogenous ligands are unknown. Here, we show that a group of class A/rhodopsin-like orphan GPCRs including GPR61, GPR161 and GPR174 increase the cAMP level similarly to fully activated D1 dopamine receptor (D1R). We report cryo-electron microscopy structures of the GPR61‒Gs, GPR161‒Gs and GPR174‒Gs complexes without any exogenous ligands. The GPR174 structure reveals that endogenous lysophosphatidylserine (lysoPS) is copurified. While GPR174 fails to respond to exogenous lysoPS, likely owing to its maximal activation by the endogenous ligand, GPR174 mutants with lower ligand binding affinities can be specifically activated by lysoPS but not other lipids, in a dose-dependent manner. Moreover, GPR174 adopts a non-canonical Gs coupling mode. The structures of GPR161 and GPR61 reveal that the second extracellular loop (ECL2) penetrates into the orthosteric pocket, possibly contributing to constitutive activity. Our work definitively confirms lysoPS as an endogenous GPR174 ligand and suggests that high constitutive activity of some orphan GPCRs could be accounted for by their having naturally abundant ligands.
Collapse
Affiliation(s)
- Yingying Nie
- College of Life Sciences, Beijing Normal University, 100875, Beijing, China
- National Institute of Biological Sciences, 102206, Beijing, China
| | - Zeming Qiu
- National Institute of Biological Sciences, 102206, Beijing, China
- Tsinghua Institute of Multidisciplinary Biomedical Research, Tsinghua University, 100084, Beijing, China
| | - Sijia Chen
- National Institute of Biological Sciences, 102206, Beijing, China
| | - Zhao Chen
- National Institute of Biological Sciences, 102206, Beijing, China
- Tsinghua Institute of Multidisciplinary Biomedical Research, Tsinghua University, 100084, Beijing, China
| | - Xiaocui Song
- National Institute of Biological Sciences, 102206, Beijing, China
| | - Yan Ma
- National Institute of Biological Sciences, 102206, Beijing, China
- Tsinghua Institute of Multidisciplinary Biomedical Research, Tsinghua University, 100084, Beijing, China
| | - Niu Huang
- National Institute of Biological Sciences, 102206, Beijing, China
- Tsinghua Institute of Multidisciplinary Biomedical Research, Tsinghua University, 100084, Beijing, China
| | - Jason G Cyster
- HHMI, University of California, San Francisco, CA, 94143, USA
- Department of Microbiology and Immunology, University of California, San Francisco, CA, 94143, USA
| | - Sanduo Zheng
- College of Life Sciences, Beijing Normal University, 100875, Beijing, China.
- National Institute of Biological Sciences, 102206, Beijing, China.
- Tsinghua Institute of Multidisciplinary Biomedical Research, Tsinghua University, 100084, Beijing, China.
| |
Collapse
|
9
|
Bolinger AA, Frazier A, La JH, Allen JA, Zhou J. Orphan G Protein-Coupled Receptor GPR37 as an Emerging Therapeutic Target. ACS Chem Neurosci 2023; 14:3318-3334. [PMID: 37676000 PMCID: PMC11144446 DOI: 10.1021/acschemneuro.3c00479] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/08/2023] Open
Abstract
G protein-coupled receptors (GPCRs) are successful druggable targets, making up around 35% of all FDA-approved medications. However, a large number of receptors remain orphaned, with no known endogenous ligand, representing a challenging but untapped area to discover new therapeutic targets. Among orphan GPCRs (oGPCRs) of interest, G protein-coupled receptor 37 (GPR37) is highly expressed in the central nervous system (CNS), particularly in the spinal cord and oligodendrocytes. While its cellular signaling mechanisms and endogenous receptor ligands remain elusive, GPR37 has been implicated in several important neurological conditions, including Parkinson's disease (PD), inflammation, pain, autism, and brain tumors. GPR37 structure, signaling, emerging physiology, and pharmacology are reviewed while integrating a discussion on potential therapeutic indications and opportunities.
Collapse
Affiliation(s)
- Andrew A. Bolinger
- Department of Pharmacology and Toxicology, Center for Addiction Sciences and Therapeutics, University of Texas Medical Branch, Galveston, Texas 77555, United States
| | - Andrew Frazier
- Department of Pharmacology and Toxicology, Center for Addiction Sciences and Therapeutics, University of Texas Medical Branch, Galveston, Texas 77555, United States
| | - Jun-Ho La
- Department of Neurobiology, University of Texas Medical Branch, Galveston, Texas 77555, United States
| | - John A. Allen
- Department of Pharmacology and Toxicology, Center for Addiction Sciences and Therapeutics, University of Texas Medical Branch, Galveston, Texas 77555, United States
| | - Jia Zhou
- Department of Pharmacology and Toxicology, Center for Addiction Sciences and Therapeutics, University of Texas Medical Branch, Galveston, Texas 77555, United States
| |
Collapse
|
10
|
Wang P, Lv L, Li H, Wang CY, Zhou J. Opportunities and challenges in drug discovery targeting the orphan receptor GPR12. Drug Discov Today 2023; 28:103698. [PMID: 37422169 DOI: 10.1016/j.drudis.2023.103698] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Revised: 06/26/2023] [Accepted: 07/04/2023] [Indexed: 07/10/2023]
Abstract
G-protein-coupled receptor 12 (GPR12) is a brain-specific expression orphan G-protein-coupled receptor (oGPCR) that regulates various physiological processes. It is an emerging therapeutic target for central nervous system (CNS) disorders, including Alzheimer's disease (AD), Parkinson's disease (PD), Huntington's disease (HD), attention deficit hyperactivity disorder (ADHD), and schizophrenia, as well as other human diseases, such as cancer, obesity, and metabolic disorders. GPR12 remains a less extensively investigated oGPCR, particularly in terms of its biological functions, signaling pathways, and ligand discovery. The discovery of drug-like small-molecule modulators to probe the brain functions of GPR12 or to act as a potential drug candidates, as well as the identification of reliable biomarkers, are vital to elucidate the roles of this receptor in various human diseases and develop novel target-based therapeutics.
Collapse
Affiliation(s)
- Pingyuan Wang
- Key Laboratory of Evolution and Marine Biodiversity Ministry of Education, Institute of Evolution & Marine Biodiversity, Ocean University of China, Qingdao 266003, China; School of Medicine and Pharmacy, Ocean University of China, Qingdao 266003, China.
| | - Ling Lv
- Key Laboratory of Evolution and Marine Biodiversity Ministry of Education, Institute of Evolution & Marine Biodiversity, Ocean University of China, Qingdao 266003, China; College of Food Science and Engineering, Ocean University of China, Qingdao 266003, China
| | - Haoran Li
- Key Laboratory of Evolution and Marine Biodiversity Ministry of Education, Institute of Evolution & Marine Biodiversity, Ocean University of China, Qingdao 266003, China; School of Medicine and Pharmacy, Ocean University of China, Qingdao 266003, China
| | - Chang-Yun Wang
- Key Laboratory of Evolution and Marine Biodiversity Ministry of Education, Institute of Evolution & Marine Biodiversity, Ocean University of China, Qingdao 266003, China; School of Medicine and Pharmacy, Ocean University of China, Qingdao 266003, China; Laboratory for Marine Drugs and Bioproducts, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, China.
| | - Jia Zhou
- Chemical Biology Program, Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, TX 77555, USA.
| |
Collapse
|