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Savransky S, White AD, Vilardaga JP. Deciphering the role of glycosaminoglycans in GPCR signaling. Cell Signal 2024; 118:111149. [PMID: 38522808 PMCID: PMC10999332 DOI: 10.1016/j.cellsig.2024.111149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2024] [Revised: 03/11/2024] [Accepted: 03/21/2024] [Indexed: 03/26/2024]
Abstract
G protein-coupled receptors (GPCR) and glycosaminoglycans (GAGs) are two essential components of the cell surface that regulate physiological processes in the body. GPCRs are the most extensive family of transmembrane receptors that control cellular responses to extracellular stimuli, while GAGs are polysaccharides that contribute to the function of the extracellular matrix (ECM). Due to their proximity to the plasma membrane, GAGs participate in signal transduction by interacting with various extracellular molecules and cell surface receptors. GAGs can directly interact with certain GPCRs or their ligands (chemokines, peptide hormones and neuropeptides, structural proteins, and enzymes) from the glutamate receptor family, the rhodopsin receptor family, the adhesion receptor family, and the secretin receptor family. These interactions have recently become an emerging topic, providing a new avenue for understanding how GPCR signaling is regulated. This review discusses our current state of knowledge about the role of GAGs in GPCR signaling and function.
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Affiliation(s)
- Sofya Savransky
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA; Graduate Program in Molecular Pharmacology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA.
| | - Alex D White
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA; Graduate Program in Molecular Pharmacology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA
| | - Jean-Pierre Vilardaga
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA.
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2
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Kuhn CK, Stenzel U, Berndt S, Liebscher I, Schöneberg T, Horn S. The repertoire and structure of adhesion GPCR transcript variants assembled from publicly available deep-sequenced human samples. Nucleic Acids Res 2024; 52:3823-3836. [PMID: 38421639 DOI: 10.1093/nar/gkae145] [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: 09/27/2023] [Revised: 01/24/2024] [Accepted: 02/19/2024] [Indexed: 03/02/2024] Open
Abstract
Alternative splicing and multiple transcription start and termination sites can produce a diverse repertoire of mRNA transcript variants from a given gene. While the full picture of the human transcriptome is still incomplete, publicly available RNA datasets have enabled the assembly of transcripts. Using publicly available deep sequencing data from 927 human samples across 48 tissues, we quantified known and new transcript variants, provide an interactive, browser-based application Splice-O-Mat and demonstrate its relevance using adhesion G protein-coupled receptors (aGPCRs) as an example. On average, 24 different transcript variants were detected for each of the 33 human aGPCR genes, and several dominant transcript variants were not yet annotated. Variable transcription starts and complex exon-intron structures encode a flexible protein domain architecture of the N- and C termini and the seven-transmembrane helix domain (7TMD). Notably, we discovered the first GPCR (ADGRG7/GPR128) with eight transmembrane helices. Both the N- and C terminus of this aGPCR were intracellularly oriented, anchoring the N terminus in the plasma membrane. Moreover, the assessment of tissue-specific transcript variants, also for other gene classes, in our application may change the evaluation of disease-causing mutations, as their position in different transcript variants may explain tissue-specific phenotypes.
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Affiliation(s)
- Christina Katharina Kuhn
- Rudolf Schönheimer Institute of Biochemistry, Medical Faculty, University of Leipzig, 04103 Leipzig, Germany
| | - Udo Stenzel
- Rudolf Schönheimer Institute of Biochemistry, Medical Faculty, University of Leipzig, 04103 Leipzig, Germany
| | - Sandra Berndt
- Rudolf Schönheimer Institute of Biochemistry, Medical Faculty, University of Leipzig, 04103 Leipzig, Germany
| | - Ines Liebscher
- Rudolf Schönheimer Institute of Biochemistry, Medical Faculty, University of Leipzig, 04103 Leipzig, Germany
| | - Torsten Schöneberg
- Rudolf Schönheimer Institute of Biochemistry, Medical Faculty, University of Leipzig, 04103 Leipzig, Germany
- Department of Biochemistry, School of Medicine, University of Global Health Equity (UGHE), PO Box 6955 Kigali, Rwanda
| | - Susanne Horn
- Rudolf Schönheimer Institute of Biochemistry, Medical Faculty, University of Leipzig, 04103 Leipzig, Germany
- Institute of Translational Genomics, Helmholtz Zentrum München - German Research Center for Environmental Health, 85764 Neuherberg, Germany
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3
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Dates AN, Jones DTD, Smith JS, Skiba MA, Rich MF, Burruss MM, Kruse AC, Blacklow SC. Heterogeneity of tethered agonist signaling in adhesion G protein-coupled receptors. Cell Chem Biol 2024:S2451-9456(24)00120-X. [PMID: 38608683 DOI: 10.1016/j.chembiol.2024.03.004] [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: 11/02/2023] [Revised: 01/25/2024] [Accepted: 03/19/2024] [Indexed: 04/14/2024]
Abstract
Adhesion G protein-coupled receptor (aGPCR) signaling influences development and homeostasis in a wide range of tissues. In the current model for aGPCR signaling, ligand binding liberates a conserved sequence that acts as an intramolecular, tethered agonist (TA), yet this model has not been evaluated systematically for all aGPCRs. Here, we assessed the TA-dependent activities of all 33 aGPCRs in a suite of transcriptional reporter, G protein activation, and β-arrestin recruitment assays using a new fusion protein platform. Strikingly, only ∼50% of aGPCRs exhibited robust TA-dependent activation, and unlike other GPCR families, aGPCRs showed a notable preference for G12/13 signaling. AlphaFold2 predictions assessing TA engagement in the predicted intramolecular binding pocket aligned with the TA dependence of the cellular responses. This dataset provides a comprehensive resource to inform the investigation of all human aGPCRs and for targeting aGPCRs therapeutically.
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Affiliation(s)
- Andrew N Dates
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, MA 02115, USA
| | - Daniel T D Jones
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, MA 02115, USA
| | - Jeffrey S Smith
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, MA 02115, USA; Department of Dermatology, Brigham and Women's Hospital, 221 Longwood Avenue, Boston, MA 02115, USA
| | - Meredith A Skiba
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, MA 02115, USA
| | - Maria F Rich
- University of Cincinnati School of Medicine, Department of Molecular Genetics, Biochemistry, and Microbiology, Cincinnati, OH 45267, USA
| | - Maggie M Burruss
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, MA 02115, USA
| | - Andrew C Kruse
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, MA 02115, USA
| | - Stephen C Blacklow
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, MA 02115, USA; Department of Cancer Biology, Dana Farber Cancer Institute, Boston, MA 02215, USA.
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4
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Öz-Arslan D, Durer ZA, Kan B. G protein-coupled receptor-mediated autophagy in health and disease. Br J Pharmacol 2024. [PMID: 38501194 DOI: 10.1111/bph.16345] [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: 09/01/2023] [Revised: 01/05/2024] [Accepted: 01/27/2024] [Indexed: 03/20/2024] Open
Abstract
G protein-coupled receptors (GPCRs) constitute the largest and most diverse superfamily of mammalian transmembrane proteins. These receptors are involved in a wide range of physiological functions and are targets for more than a third of available drugs in the market. Autophagy is a cellular process involved in degrading damaged proteins and organelles and in recycling cellular components. Deficiencies in autophagy are involved in a variety of pathological conditions. Both GPCRs and autophagy are essential in preserving homeostasis and cell survival. There is emerging evidence suggesting that GPCRs are direct regulators of autophagy. Additionally, autophagic machinery is involved in the regulation of GPCR signalling. The interplay between GPCR and autophagic signalling mechanisms significantly impacts on health and disease; however, there is still an incomplete understanding of the underlying mechanisms and therapeutic implications in different tissues and disease contexts. This review aims to discuss the interactions between GPCR and autophagy signalling. Studies on muscarinic receptors, beta-adrenoceptors, taste receptors, purinergic receptors and adhesion GPCRs are summarized, in relation to autophagy.
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Affiliation(s)
- Devrim Öz-Arslan
- Department of Biophysics, Acibadem MAA University, School of Medicine, Istanbul, Turkey
| | - Zeynep Aslıhan Durer
- Department of Biophysics, Acibadem MAA University, School of Medicine, Istanbul, Turkey
- Department of Biochemistry, Acibadem MAA University, School of Pharmacy, Istanbul, Turkey
| | - Beki Kan
- Department of Biophysics, Acibadem MAA University, School of Medicine, Istanbul, Turkey
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5
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Wang S, Bi J, Li C, Li B. Latrophilin, an adhesion GPCR with galactose-binding lectin domain involved in the innate immune response of Tribolium castaneum. Int J Biol Macromol 2023; 253:126707. [PMID: 37673160 DOI: 10.1016/j.ijbiomac.2023.126707] [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: 05/31/2023] [Revised: 08/28/2023] [Accepted: 09/03/2023] [Indexed: 09/08/2023]
Abstract
Latrophilin is a member of adhesion GPCRs involved in various physiological pro1cesses. The extracellular fragment of Tribolium castaneum Latrophilin (TcLph) contains a galactose-binding lectin (GBL) domain. However, the biological function of GBL domain remains mysterious. Here, we initially studied the role of TcLph in recognizing pathogens through its GBL domain and then triggering immune defense in invertebrates. Results showed that GBL domain was highly conserved, and its predicted 3D structure was similar to rhamnose-binding lectin domain of mouse Latrophilin-1 with a unique α/β fold and two long loops. Molecular docking and ELISA results revealed the GBL domain can bind to D-galactose, L-rhamnose, lipopolysaccharide and peptidoglycan. The recombinant extracellular segment of TcLph and the recombinant GBL exhibited strong agglutinating and binding activities to all tested bacteria in a Ca2+-dependent manner. Moreover, TcLph was markedly induced after infection by Escherichia coli or Staphylococcus aureus, while its silencing exacerbated bacterial loads and larvae mortality. TcLph-deficient larvae significantly decreased the transcription levels of antimicrobial peptides and prophenoloxidase activating system-related genes, leading to a significant reduction in phenoloxidase activity. It indicated that TcLph functioned as a pattern recognition receptor in pathogen recognition and activated immune responses to eliminate invasive microbes, suggesting a potential target for insecticides.
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Affiliation(s)
- Suisui Wang
- Jiangsu Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing 210023, China
| | - Jingxiu Bi
- Jiangsu Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing 210023, China; Laboratory of Quality and Safety Risk Assessment for Agro-Products of the Ministry of Agriculture (Jinan), Institute of Quality Standard and Testing Technology for Agro-Products, Shandong Academy of Agricultural Sciences, Jinan, Shandong, China
| | - Chengjun Li
- Jiangsu Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing 210023, China
| | - Bin Li
- Jiangsu Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing 210023, China.
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6
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Kieslich B, Weiße RH, Brendler J, Ricken A, Schöneberg T, Sträter N. The dimerized pentraxin-like domain of the adhesion G protein-coupled receptor 112 (ADGRG4) suggests function in sensing mechanical forces. J Biol Chem 2023; 299:105356. [PMID: 37863265 PMCID: PMC10687090 DOI: 10.1016/j.jbc.2023.105356] [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: 10/14/2022] [Revised: 09/12/2023] [Accepted: 10/11/2023] [Indexed: 10/22/2023] Open
Abstract
Adhesion G protein-coupled receptors (aGPCRs) feature large extracellular regions with modular domains that often resemble protein classes of various function. The pentraxin (PTX) domain, which is predicted by sequence homology within the extracellular region of four different aGPCR members, is well known to form pentamers and other oligomers. Oligomerization of GPCRs is frequently reported and mainly driven by interactions of the seven-transmembrane region and N or C termini. While the functional importance of dimers is well-established for some class C GPCRs, relatively little is known about aGPCR multimerization. Here, we showcase the example of ADGRG4, an orphan aGPCR that possesses a PTX-like domain at its very N-terminal tip, followed by an extremely long stalk containing serine-threonine repeats. Using X-ray crystallography and biophysical methods, we determined the structure of this unusual PTX-like domain and provide experimental evidence for a homodimer equilibrium of this domain which is Ca2+-independent and driven by intermolecular contacts that differ vastly from the known soluble PTXs. The formation of this dimer seems to be conserved in mammalian ADGRG4 indicating functional relevance. Our data alongside of theoretical considerations lead to the hypothesis that ADGRG4 acts as an in vivo sensor for shear forces in enterochromaffin and Paneth cells of the small intestine.
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Affiliation(s)
- Björn Kieslich
- Institute of Bioanalytical Chemistry, Center for Biotechnology and Biomedicine, Leipzig University, Leipzig, Germany; Rudolf Schönheimer Institute of Biochemistry, Medical Faculty, Leipzig University, Leipzig, Germany.
| | - Renato H Weiße
- Institute of Bioanalytical Chemistry, Center for Biotechnology and Biomedicine, Leipzig University, Leipzig, Germany
| | - Jana Brendler
- Institute of Anatomy, Medical Faculty, Leipzig University, Leipzig, Germany
| | - Albert Ricken
- Institute of Anatomy, Medical Faculty, Leipzig University, Leipzig, Germany
| | - Torsten Schöneberg
- Rudolf Schönheimer Institute of Biochemistry, Medical Faculty, Leipzig University, Leipzig, Germany.
| | - Norbert Sträter
- Institute of Bioanalytical Chemistry, Center for Biotechnology and Biomedicine, Leipzig University, Leipzig, Germany.
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7
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Wang N, Qian Y, Xia R, Zhu X, Xiong Y, Zhang A, Guo C, He Y. Structural basis of CD97 activation and G-protein coupling. Cell Chem Biol 2023; 30:1343-1353.e5. [PMID: 37673067 DOI: 10.1016/j.chembiol.2023.08.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Revised: 06/21/2023] [Accepted: 08/15/2023] [Indexed: 09/08/2023]
Abstract
CD97 (ADGRE5) is an adhesion G protein-coupled receptor (aGPCR) which plays crucial roles in immune system and cancer. However, the mechanism of CD97 activation and the determinant of G13 coupling selectivity remain unknown. Here, we present the cryo-electron microscopy structures of human CD97 in complex with G13, Gq, and Gs. Our structures reveal the stalk peptide recognition mode of CD97, adding missing information of the current tethered-peptide activation model of aGPCRs. For instance, a revised "FXφφφ" motif and a framework of conserved aromatic residues in the ligand-binding pocket. Importantly, structural comparisons of G13, Gq, and Gs engagements of CD97 reveal key determinants of G13 coupling selectivity, where a deep insertion of the α helix 5 and a closer contact with the transmembrane helix 6, 5, and 3 dictate coupling preferences. Taken together, our structural study of CD97 provides a framework for understanding CD97 signaling and the G13 coupling selectivity.
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Affiliation(s)
- Na Wang
- Laboratory of Receptor Structure and Signaling, HIT Center for Life Sciences, School of Life Science and Technology, Harbin Institute of Technology, Harbin 150001, China
| | - Yu Qian
- Laboratory of Receptor Structure and Signaling, HIT Center for Life Sciences, School of Life Science and Technology, Harbin Institute of Technology, Harbin 150001, China
| | - Ruixue Xia
- Laboratory of Receptor Structure and Signaling, HIT Center for Life Sciences, School of Life Science and Technology, Harbin Institute of Technology, Harbin 150001, China
| | - Xinyan Zhu
- Laboratory of Receptor Structure and Signaling, HIT Center for Life Sciences, School of Life Science and Technology, Harbin Institute of Technology, Harbin 150001, China
| | - Yangjie Xiong
- Laboratory of Receptor Structure and Signaling, HIT Center for Life Sciences, School of Life Science and Technology, Harbin Institute of Technology, Harbin 150001, China
| | - Anqi Zhang
- Laboratory of Receptor Structure and Signaling, HIT Center for Life Sciences, School of Life Science and Technology, Harbin Institute of Technology, Harbin 150001, China
| | - Changyou Guo
- Laboratory of Receptor Structure and Signaling, HIT Center for Life Sciences, School of Life Science and Technology, Harbin Institute of Technology, Harbin 150001, China
| | - Yuanzheng He
- Laboratory of Receptor Structure and Signaling, HIT Center for Life Sciences, School of Life Science and Technology, Harbin Institute of Technology, Harbin 150001, China.
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8
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Seufert F, Chung YK, Hildebrand PW, Langenhan T. 7TM domain structures of adhesion GPCRs: what's new and what's missing? Trends Biochem Sci 2023; 48:726-739. [PMID: 37349240 DOI: 10.1016/j.tibs.2023.05.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2023] [Revised: 05/05/2023] [Accepted: 05/19/2023] [Indexed: 06/24/2023]
Abstract
Adhesion-type G protein-coupled receptors (aGPCRs) have long resisted approaches to resolve the structural details of their heptahelical transmembrane (7TM) domains. Single-particle cryogenic electron microscopy (cryo-EM) has recently produced aGPCR 7TM domain structures for ADGRD1, ADGRG1, ADGRG2, ADGRG3, ADGRG4, ADGRG5, ADGRF1, and ADGRL3. We review the unique properties, including the position and conformation of their activating tethered agonist (TA) and signaling motifs within the 7TM bundle, that the novel structures have helped to identify. We also discuss questions that the kaleidoscope of novel aGPCR 7TM domain structures have left unanswered. These concern the relative positions, orientations, and interactions of the 7TM and GPCR autoproteolysis-inducing (GAIN) domains with one another. Clarifying their interplay remains an important goal of future structural studies on aGPCRs.
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Affiliation(s)
- Florian Seufert
- Institute of Medical Physics and Biophysics, Medical Faculty, Leipzig University, Härtelstrasse 16-18, 04107 Leipzig, Germany
| | - Yin Kwan Chung
- Rudolf Schönheimer Institute of Biochemistry, Division of General Biochemistry, Medical Faculty, Leipzig University, Johannisallee 30, 04103 Leipzig, Germany
| | - Peter W Hildebrand
- Institute of Medical Physics and Biophysics, Medical Faculty, Leipzig University, Härtelstrasse 16-18, 04107 Leipzig, Germany; Institute of Medical Physics and Biophysics, Charité - Universitätsmedizin Berlin, Berlin, Germany.
| | - Tobias Langenhan
- Rudolf Schönheimer Institute of Biochemistry, Division of General Biochemistry, Medical Faculty, Leipzig University, Johannisallee 30, 04103 Leipzig, Germany.
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9
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Dumas L, Marfoglia M, Yang B, Hijazi M, Larabi AN, Lau K, Pojer F, Nash MA, Barth P. Uncovering and engineering the mechanical properties of the adhesion GPCR ADGRG1 GAIN domain. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.04.05.535724. [PMID: 37066252 PMCID: PMC10104041 DOI: 10.1101/2023.04.05.535724] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/18/2023]
Abstract
Key cellular functions depend on the transduction of extracellular mechanical signals by specialized membrane receptors including adhesion G-protein coupled receptors (aGPCRs). While recently solved structures support aGPCR activation through shedding of the extracellular GAIN domain, the molecular mechanisms underpinning receptor mechanosensing remain poorly understood. When probed using single-molecule atomic force spectroscopy and molecular simulations, ADGRG1 GAIN dissociated from its tethered agonist at forces significantly higher than other reported signaling mechanoreceptors. Strong mechanical resistance was achieved through specific structural deformations and force propagation pathways under mechanical load. ADGRG1 GAIN variants computationally designed to lock the alpha and beta subdomains and rewire mechanically-induced structural deformations were found to modulate the GPS-Stachel rupture forces. Our study provides unprecedented insights into the molecular underpinnings of GAIN mechanical stability and paves the way for engineering mechanosensors, better understanding aGPCR function, and informing drug-discovery efforts targeting this important receptor class.
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10
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Pederick DT, Perry-Hauser NA, Meng H, He Z, Javitch JA, Luo L. Context-dependent requirement of G protein coupling for Latrophilin-2 in target selection of hippocampal axons. eLife 2023; 12:e83529. [PMID: 36939320 PMCID: PMC10118387 DOI: 10.7554/elife.83529] [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: 09/17/2022] [Accepted: 03/16/2023] [Indexed: 03/21/2023] Open
Abstract
The formation of neural circuits requires extensive interactions of cell-surface proteins to guide axons to their correct target neurons. Trans-cellular interactions of the adhesion G protein-coupled receptor latrophilin-2 (Lphn2) with its partner teneurin-3 instruct the precise assembly of hippocampal networks by reciprocal repulsion. Lphn2 acts as a repulsive receptor in distal CA1 neurons to direct their axons to the proximal subiculum, and as a repulsive ligand in the proximal subiculum to direct proximal CA1 axons to the distal subiculum. It remains unclear if Lphn2-mediated intracellular signaling is required for its role in either context. Here, we show that Lphn2 couples to Gα12/13 in heterologous cells; this coupling is increased by constitutive exposure of the tethered agonist. Specific mutations of Lphn2's tethered agonist region disrupt its G protein coupling and autoproteolytic cleavage, whereas mutating the autoproteolytic cleavage site alone prevents cleavage but preserves a functional tethered agonist. Using an in vivo misexpression assay, we demonstrate that wild-type Lphn2 misdirects proximal CA1 axons to the proximal subiculum and that Lphn2 tethered agonist activity is required for its role as a repulsive receptor in axons. By contrast, neither tethered agonist activity nor autoproteolysis were necessary for Lphn2's role as a repulsive ligand in the subiculum target neurons. Thus, tethered agonist activity is required for Lphn2-mediated neural circuit assembly in a context-dependent manner.
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Affiliation(s)
- Daniel T Pederick
- Department of Biology, Howard Hughes Medical Institute, Stanford UniversityStanfordUnited States
| | - Nicole A Perry-Hauser
- Departments of Psychiatry and Molecular Pharmacology and Therapeutics, Columbia University Vagelos College of Physicians and SurgeonsNew YorkUnited States
- Division of Molecular Therapeutics, New York State Psychiatric InstituteNew YorkUnited States
| | - Huyan Meng
- F.M. Kirby Neurobiology Center, Department of Neurology, Boston Children’s Hospital, Harvard Medical SchoolBostonUnited States
| | - Zhigang He
- F.M. Kirby Neurobiology Center, Department of Neurology, Boston Children’s Hospital, Harvard Medical SchoolBostonUnited States
| | - Jonathan A Javitch
- Departments of Psychiatry and Molecular Pharmacology and Therapeutics, Columbia University Vagelos College of Physicians and SurgeonsNew YorkUnited States
- Division of Molecular Therapeutics, New York State Psychiatric InstituteNew YorkUnited States
| | - Liqun Luo
- Department of Biology, Howard Hughes Medical Institute, Stanford UniversityStanfordUnited States
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