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Bauer L, Edwards J, Heil A, Dewitt S, Biebermann H, Aeschlimann D, Knäuper V. Mesenchymal Transglutaminase 2 Activates Epithelial ADAM17: Link to G-Protein-Coupled Receptor 56 (ADGRG1) Signalling. Int J Mol Sci 2024; 25:2329. [PMID: 38397010 PMCID: PMC10889368 DOI: 10.3390/ijms25042329] [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: 01/12/2024] [Revised: 02/06/2024] [Accepted: 02/07/2024] [Indexed: 02/25/2024] Open
Abstract
A wound healing model was developed to elucidate the role of mesenchymal-matrix-associated transglutaminase 2 (TG2) in keratinocyte re-epithelialisation. TG2 drives keratinocyte migratory responses by activation of disintegrin and metalloproteinase 17 (ADAM17). We demonstrate that epidermal growth factor (EGF) receptor ligand shedding leads to EGFR-transactivation and subsequent rapid keratinocyte migration on TG2-positive ECM. In contrast, keratinocyte migration was impaired in TG2 null conditions. We show that keratinocytes express the adhesion G-protein-coupled receptor, ADGRG1 (GPR56), which has been proposed as a TG2 receptor. Using ADAM17 activation as a readout and luciferase reporter assays, we demonstrate that TG2 activates GPR56. GPR56 activation by TG2 reached the same level as observed with an agonistic N-GPR56 antibody. The N-terminal GPR56 domain is required for TG2-regulated signalling response, as the constitutively active C-GPR56 receptor was not activated by TG2. Signalling required the C-terminal TG2 β-barrel domains and involved RhoA-associated protein kinase (ROCK) and ADAM17 activation, which was blocked by specific inhibitors. Cell surface binding of TG2 to the N-terminal GPR56 domain is rapid and is associated with TG2 and GPR56 endocytosis. TG2 and GPR56 represent a ligand receptor pair causing RhoA and EGFR transactivation. Furthermore, we determined a binding constant for the interaction of human TG2 with N-GPR56 and show for the first time that only the calcium-enabled "open" TG2 conformation associates with N-GPR56.
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Affiliation(s)
- Lea Bauer
- College of Biomedical and Life Sciences, School of Dentistry, Cardiff University, Cardiff CF14 4XY, UK (S.D.)
| | - Jessica Edwards
- College of Biomedical and Life Sciences, School of Dentistry, Cardiff University, Cardiff CF14 4XY, UK (S.D.)
| | - Andreas Heil
- College of Biomedical and Life Sciences, School of Dentistry, Cardiff University, Cardiff CF14 4XY, UK (S.D.)
| | - Sharon Dewitt
- College of Biomedical and Life Sciences, School of Dentistry, Cardiff University, Cardiff CF14 4XY, UK (S.D.)
| | - Heike Biebermann
- Institute of Experimental Pediatric Endocrinology, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Charité—Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin, Germany
| | - Daniel Aeschlimann
- College of Biomedical and Life Sciences, School of Dentistry, Cardiff University, Cardiff CF14 4XY, UK (S.D.)
| | - Vera Knäuper
- College of Biomedical and Life Sciences, School of Dentistry, Cardiff University, Cardiff CF14 4XY, UK (S.D.)
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2
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Faas F, Nørskov A, Holst PJ, Andersson AM, Qvortrup K, Mathiasen S, Rosenkilde MM. Re-routing GPR56 signalling using Gα 12/13 G protein chimeras. Basic Clin Pharmacol Toxicol 2023; 133:378-389. [PMID: 37621135 DOI: 10.1111/bcpt.13935] [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: 04/20/2023] [Revised: 08/18/2023] [Accepted: 08/21/2023] [Indexed: 08/26/2023]
Abstract
Adhesion G protein-coupled receptors (aGPCRs) constitute the second largest subclass of the GPCR superfamily. Although canonical GPCRs are explored pharmacologically as drug targets, no clinically approved drugs target the aGPCR family so far. The aGPCR GPR56/ADGRG1 stands out as an especially promising target, given its direct link to the monogenetic disease bilateral frontoparietal polymicrogyria and implications in cancers. Key to understanding GPCR pharmacology has been mapping out intracellular signalling activity. Detection of GPCR signalling in the Gαs /Gαi /Gαq G protein pathways is feasible with second messenger detection systems. However, in the case of Gα12/13 -coupled receptors, like GPR56, signalling detection is more challenging due to the lack of direct second messenger generation. To overcome this challenge, we engineered a Gαq chimera to translate Gα12/13 signalling. We show the ability of the chimeric GαΔ6q12myr and GαΔ6q13myr to translate basal Gα12/13 signalling of GPR56 to a Gαq readout in transcription factor luciferase reporter systems and show that the established peptide ligands (P7 and P19) function to enhance this signal. We further demonstrate the ability to directly influence the generation of second messengers in inositol-3-phosphate assays. In the future, these chimeric G proteins could facilitate basic functional studies, drug screenings and deorphanization of other aGPCRs.
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Affiliation(s)
- Felix Faas
- Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Amalie Nørskov
- Department of Chemistry, Technical University of Denmark, Lyngby, Denmark
| | - Peter J Holst
- Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
- InProTher APS, Copenhagen, Denmark
| | | | - Katrine Qvortrup
- Department of Chemistry, Technical University of Denmark, Lyngby, Denmark
| | - Signe Mathiasen
- Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Mette M Rosenkilde
- Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
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3
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Cevheroğlu O, Demir N, Kesici MS, Özçubukçu S, Son ÇD. Downstream signalling of the disease-associated mutations on GPR56/ADGRG1. Basic Clin Pharmacol Toxicol 2023; 133:331-341. [PMID: 37056198 DOI: 10.1111/bcpt.13873] [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: 01/10/2023] [Revised: 03/02/2023] [Accepted: 04/01/2023] [Indexed: 04/15/2023]
Abstract
GPR56/ADGRG1 is an adhesion G protein-coupled receptor (GPCR) and mutations on this receptor cause cortical malformation due to the over-migration of neural progenitor cells on brain surface. At pial surface, GPR56 interacts with collagen III, induces Rho-dependent activation through Gα12/13 and inhibits the neuronal migration. In human glioma cells, GPR56 inhibits cell migration through Gαq/11 -dependent Rho pathway. GPR56-tetraspanin complex is known to couple Gαq/11 . GPR56 is an aGPCR that couples with various G proteins and signals through different downstream pathways. In this study, bilateral frontoparietal polymicrogyria (BFPP) mutants disrupting GPR56 function but remaining to be expressed on plasma membrane were used to study receptor signalling through Gα12 , Gα13 and Gα11 with BRET biosensors. GPR56 showed coupling with all three G proteins and activated heterotrimeric G protein signalling upon stimulation with Stachel peptide. However, BFPP mutants showed different signalling defects for each G protein indicative of distinct activation and signalling properties of GPR56 for Gα12 , Gα13 or Gα11 . β-arrestin recruitment was also investigated following the activation of GPR56 with Stachel peptide using BRET biosensors. N-terminally truncated GPR56 showed enhanced β-arrestin recruitment; however, neither wild-type receptor nor BFPP mutants gave any measurable recruitment upon Stachel stimulation, pointing different activation mechanisms for β-arrestin involvement.
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Affiliation(s)
| | - Nil Demir
- Department of Biological Sciences, Middle East Technical University, Ankara, Türkiye
| | | | - Salih Özçubukçu
- Department of Chemistry, Middle East Technical University, Ankara, Türkiye
| | - Çağdaş D Son
- Department of Biological Sciences, Middle East Technical University, Ankara, Türkiye
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4
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Kuo CY, Tsai MH, Lin HH, Wang YC, Singh AK, Chang CC, Lin JJ, Hung PC, Lin KL. Identification and clinical characteristics of a novel missense ADGRG1 variant in bilateral Frontoparietal Polymicrogyria: The electroclinical change from infancy to adulthood after Callosotomy in three siblings. Epilepsia Open 2023; 8:154-164. [PMID: 36524291 PMCID: PMC9977754 DOI: 10.1002/epi4.12685] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2022] [Accepted: 12/10/2022] [Indexed: 12/23/2022] Open
Abstract
OBJECTIVE Bilateral frontoparietal polymicrogyria (BFPP) is a rare genetic-related migration disorder. It has been attributed to loss-of-function of the ADGRG1 gene, which encodes an adhesion G protein-coupled receptor, ADGRG1/GPR56. We report the EEG findings of BFPP in three Asian patients, and confirmed that change in protein function was caused by the novel missense variant (p.Leu290Pro). METHODS We reviewed the medical records of three siblings with BFPP including one elder girl and two identical twin boys from birth to adulthood. The clinical symptoms, electroencephalography (EEG), brain MRI, whole-exome sequencing, treatment including medications, neuromodulation, and epilepsy surgery, and clinical outcomes were reviewed. The protein structure of a novel missense variant (p.Leu290Pro) was predicted by in silico studies, and molecular analysis was performed via typical flow cytometry and Western blotting. RESULTS The elder girl (Patient 1) was 22 years old and the twin boys (Patients 2 and 3) were 20 years old at the time of publication. All of them presented with typical clinical symptoms/signs and MRI findings of BFPP. Whole-exome sequencing followed by Sanger confirmation showed that all three patients had compound heterozygous variants in the ADGRG1 gene. The missense variant (p.Leu290Pro) was confirmed to be related to a reduction in cell surface GPR56 expression. High-amplitude rhythmic activity was noted in sleep EEG during infancy, which may have been due to excessive sleep spindle, and the rhythm disappeared when they were of pre-school age. Partial callosotomy provided short-term benefits in seizure control in Patients 1 and 2, and combined vagus nerve stimulation and partial callosotomy provided longer benefits in Patient 3. SIGNIFICANCE Sleep EEG findings of high-amplitude rhythmic activity in our BFPP cases were only noted during infancy and childhood. We also confirmed that the missense variant (p.Leu290Pro) led to loss of function due to a reduction in cell surface GPR56 expression.
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Affiliation(s)
- Cheng-Yen Kuo
- Division of Pediatric Neurology, Chang Gung Children's Hospital and Chang Gung Memorial Hospital, Taoyuan, Taiwan
| | - Meng-Han Tsai
- School of Medicine, College of Medicine, Chang Gung University, Taoyuan, Taiwan.,Department of Neurology, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan
| | - Hsi-Hsien Lin
- Department of Microbiology and Immunology, College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Yu-Chi Wang
- Department of Neurosurgery, Chang Gung Memorial Hospital at Linkou, Chang Gung University, Taoyuan, Taiwan
| | - Abhishek Kumar Singh
- Department of Biological Sciences, Indian Institute of Science Education and Research, Mohali, India
| | - Chin-Chen Chang
- Department of Medical Imaging and Intervention, Chang Gung Memorial Hospital, Linkou, Chang Gung University, Taoyuan, Taiwan
| | - Jainn-Jim Lin
- Division of Pediatric Neurology, Chang Gung Children's Hospital and Chang Gung Memorial Hospital, Taoyuan, Taiwan.,School of Medicine, College of Medicine, Chang Gung University, Taoyuan, Taiwan.,Division of Pediatric Critical Care and Pediatric Neurocritical Care Center, Chang Gung Children's Hospital and Chang Gung Memorial Hospital, Taoyuan, Taiwan
| | - Po-Cheng Hung
- Division of Pediatric Neurology, Chang Gung Children's Hospital and Chang Gung Memorial Hospital, Taoyuan, Taiwan.,School of Medicine, College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Kuang-Lin Lin
- Division of Pediatric Neurology, Chang Gung Children's Hospital and Chang Gung Memorial Hospital, Taoyuan, Taiwan.,School of Medicine, College of Medicine, Chang Gung University, Taoyuan, Taiwan
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5
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Nojima Y, Toriyama M, Tago K, Mizuno N, Morishita K, Itoh H. GPR56 C-terminal fragment mediates signal received by N-terminal fragment of another adhesion GPCR Latrophilin1 in neurons. Genes Cells 2023; 28:83-96. [PMID: 36453010 DOI: 10.1111/gtc.12994] [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: 11/20/2022] [Accepted: 11/25/2022] [Indexed: 12/03/2022]
Abstract
Adhesion GPCRs (aGPCRs) are a subfamily of GPCRs that are involved in cell adhesion, cell proliferation, and cell migration in various tissues. G protein-coupled receptor proteolytic site (GPS) of aGPCR is required to cleave the extracellular domain autocatalytically, generating two fragments; a N-terminal fragment (NTF) and a C-terminal fragment (CTF) containing seven transmembrane structure. NTF can interact with CTF non-covalently after cleavage, however the physiological significance of the cleavage of aGPCR at GPS, and also the interaction between NTF and CTF have not been fully clarified yet. In this study, we first investigated the expression profiles of two aGPCRs, GPR56/ADGRG1, and LPHN1/ADGRL1 in mouse brain, and found that the NTF and CTF of GPR56 independently expressed in different brain region at different developmental stages. Immunoprecipitation of GPR56CTF co-immunoprecipitated LPHN1NTF from mouse brain and HEK293T cells expressing both fragments. Stimulation with LPHN1 ligand, α-Latrotoxin N4C (αLTXN4C), to cells expressing LPHN1NTF and GPR56CTF increased intracellular Ca2+ concentration ([Ca2+ ]i). We also demonstrated that GPR56KO mouse neurons attenuated their Ca2+ response to αLTXN4C. These results suggest the possibility of functional and chimeric complex containing LPHN1NTF and GPR56CTF in neuronal signal transduction.
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Affiliation(s)
- Yusuke Nojima
- Laboratory of Molecular Signal Transduction, Division of Biological Science, Nara Institute of Science and Technology, Nara, Japan
| | - Manami Toriyama
- Laboratory of Molecular Signal Transduction, Division of Biological Science, Nara Institute of Science and Technology, Nara, Japan
| | - Kenji Tago
- Division of Structural Biochemistry, Department of Biochemistry, Jichi Medical University, Tochigi, Japan
| | - Norikazu Mizuno
- Faculty of Pharmaceutical Sciences, Aomori University, Aomori, Japan
| | - Kazuhiro Morishita
- Project for Advanced Medical Research and Development, Project Research Division, Frontier Science Research Center, University of Miyazaki, Miyazaki, Japan
| | - Hiroshi Itoh
- Laboratory of Molecular Signal Transduction, Division of Biological Science, Nara Institute of Science and Technology, Nara, Japan
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Dahiya V, Bagchi G. Non-canonical androgen signaling pathways and implications in prostate cancer. BIOCHIMICA ET BIOPHYSICA ACTA. MOLECULAR CELL RESEARCH 2022; 1869:119357. [PMID: 36100060 DOI: 10.1016/j.bbamcr.2022.119357] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Revised: 08/11/2022] [Accepted: 09/01/2022] [Indexed: 06/15/2023]
Abstract
Androgen signaling is a critical determinant of timely and proper development of all male organs including the prostate. Maturation of prostate and its neoplastic transformation is intricately associated with accurate androgen signaling. Ablation of androgen has therefore been the primary treatment mechanism of Prostate cancer (PCa) patients for several decades. Upon removal, the tumor recedes for a while, yet it reappears soon, in an androgen independent state, untreatable by current therapeutic regimens. Studies reveal that apart from the classical androgen signaling pathway known and targeted for almost a century, there exist several non-canonical pathways, with marked impact on classical androgen signaling and PCa growth. These include non-genomic signaling by androgens via alternate membrane GPCRs, signaling by non-androgens that ultimately impact the androgen signaling pathway, or an integration of non-genomic and genomic response as seen in case of protein kinase A activation. Accurate understanding of these various non-canonical androgen signaling pathways and their influence on the typical androgen signaling pathway can help design important interventions for PCa patients. This review analyses in detail the various non-classical androgen signaling pathways and their impact, if any, on classical mode of androgen action and PCa.
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Affiliation(s)
- Versha Dahiya
- Amity Institute of Biotechnology, Amity University Haryana, India, 122413
| | - Gargi Bagchi
- Amity Institute of Biotechnology, Amity University Haryana, India, 122413.
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7
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Lala T, Hall RA. Adhesion G protein-coupled receptors: structure, signaling, physiology, and pathophysiology. Physiol Rev 2022; 102:1587-1624. [PMID: 35468004 PMCID: PMC9255715 DOI: 10.1152/physrev.00027.2021] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Revised: 03/11/2022] [Accepted: 04/16/2022] [Indexed: 01/17/2023] Open
Abstract
Adhesion G protein-coupled receptors (AGPCRs) are a family of 33 receptors in humans exhibiting a conserved general structure but diverse expression patterns and physiological functions. The large NH2 termini characteristic of AGPCRs confer unique properties to each receptor and possess a variety of distinct domains that can bind to a diverse array of extracellular proteins and components of the extracellular matrix. The traditional view of AGPCRs, as implied by their name, is that their core function is the mediation of adhesion. In recent years, though, many surprising advances have been made regarding AGPCR signaling mechanisms, activation by mechanosensory forces, and stimulation by small-molecule ligands such as steroid hormones and bioactive lipids. Thus, a new view of AGPCRs has begun to emerge in which these receptors are seen as massive signaling platforms that are crucial for the integration of adhesive, mechanosensory, and chemical stimuli. This review article describes the recent advances that have led to this new understanding of AGPCR function and also discusses new insights into the physiological actions of these receptors as well as their roles in human disease.
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Affiliation(s)
- Trisha Lala
- Department of Pharmacology and Chemical Biology, Emory University School of Medicine, Atlanta, Georgia
| | - Randy A Hall
- Department of Pharmacology and Chemical Biology, Emory University School of Medicine, Atlanta, Georgia
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8
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Su T, Guan Q, Cheng H, Zhu Z, Jiang C, Guo P, Tai Y, Sun H, Wang M, Wei W, Wang Q. Functions of G protein-coupled receptor 56 in health and disease. Acta Physiol (Oxf) 2022; 236:e13866. [PMID: 35959520 DOI: 10.1111/apha.13866] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Revised: 08/05/2022] [Accepted: 08/08/2022] [Indexed: 01/29/2023]
Abstract
Human G protein-coupled receptor 56 (GPR56) is encoded by gene ADGRG1 from chromosome 16q21 and is homologously encoded in mice, at chromosome 8. Both 687 and 693 splice forms are present in humans and mice. GPR56 has a 381 amino acid-long N-terminal extracellular segment and a GPCR proteolysis site upstream from the first transmembrane domain. GPR56 is mainly expressed in the heart, brain, thyroid, platelets, and peripheral blood mononuclear cells. Accumulating evidence indicates that GPR56 promotes the formation of myelin sheaths and the development of oligodendrocytes in the cerebral cortex of the central nervous system. Moreover, GPR56 contributes to the development and differentiation of hematopoietic stem cells, induces adipogenesis, and regulates the function of immune cells. The lack of GPR56 leads to nervous system dysfunction, platelet disorders, and infertility. Abnormal expression of GPR56 is related to the malignant transformation and tumor metastasis of several cancers including melanoma, neuroglioma, and gastrointestinal cancer. Metabolic disorders and cardiovascular diseases are also associated with dysregulation of GPR56 expression, and GPR56 is involved in the pharmacological resistance to some antidepressant and cancer drug treatments. In this review, the molecular structure, expression profile, and signal transduction of GPR56 are introduced, and physiological and pathological functions of GRP56 are comprehensively summarized. Attributing to its significant biological functions and its long N-terminal extracellular region that interacts with multiple ligands, GPR56 is becoming an attractive therapeutic target in treating neurological and hematopoietic diseases.
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Affiliation(s)
- Tiantian Su
- Key Laboratory of Anti-inflammatory and Immune Medicine, Ministry of Education, Anhui Collaborative Innovation Centre of Anti-inflammatory and Immune Medicine, Institute of Clinical Pharmacology, Anhui Medical University, Hefei, Anhui Province, China
| | - Qiuyun Guan
- Key Laboratory of Anti-inflammatory and Immune Medicine, Ministry of Education, Anhui Collaborative Innovation Centre of Anti-inflammatory and Immune Medicine, Institute of Clinical Pharmacology, Anhui Medical University, Hefei, Anhui Province, China
| | - Huijuan Cheng
- Key Laboratory of Anti-inflammatory and Immune Medicine, Ministry of Education, Anhui Collaborative Innovation Centre of Anti-inflammatory and Immune Medicine, Institute of Clinical Pharmacology, Anhui Medical University, Hefei, Anhui Province, China
| | - Zhenduo Zhu
- Key Laboratory of Anti-inflammatory and Immune Medicine, Ministry of Education, Anhui Collaborative Innovation Centre of Anti-inflammatory and Immune Medicine, Institute of Clinical Pharmacology, Anhui Medical University, Hefei, Anhui Province, China
| | - Chunru Jiang
- Key Laboratory of Anti-inflammatory and Immune Medicine, Ministry of Education, Anhui Collaborative Innovation Centre of Anti-inflammatory and Immune Medicine, Institute of Clinical Pharmacology, Anhui Medical University, Hefei, Anhui Province, China
| | - Paipai Guo
- Key Laboratory of Anti-inflammatory and Immune Medicine, Ministry of Education, Anhui Collaborative Innovation Centre of Anti-inflammatory and Immune Medicine, Institute of Clinical Pharmacology, Anhui Medical University, Hefei, Anhui Province, China
| | - Yu Tai
- Key Laboratory of Anti-inflammatory and Immune Medicine, Ministry of Education, Anhui Collaborative Innovation Centre of Anti-inflammatory and Immune Medicine, Institute of Clinical Pharmacology, Anhui Medical University, Hefei, Anhui Province, China
| | - Hanfei Sun
- Key Laboratory of Anti-inflammatory and Immune Medicine, Ministry of Education, Anhui Collaborative Innovation Centre of Anti-inflammatory and Immune Medicine, Institute of Clinical Pharmacology, Anhui Medical University, Hefei, Anhui Province, China
| | - Manman Wang
- Key Laboratory of Anti-inflammatory and Immune Medicine, Ministry of Education, Anhui Collaborative Innovation Centre of Anti-inflammatory and Immune Medicine, Institute of Clinical Pharmacology, Anhui Medical University, Hefei, Anhui Province, China
| | - Wei Wei
- Key Laboratory of Anti-inflammatory and Immune Medicine, Ministry of Education, Anhui Collaborative Innovation Centre of Anti-inflammatory and Immune Medicine, Institute of Clinical Pharmacology, Anhui Medical University, Hefei, Anhui Province, China
| | - Qingtong Wang
- Key Laboratory of Anti-inflammatory and Immune Medicine, Ministry of Education, Anhui Collaborative Innovation Centre of Anti-inflammatory and Immune Medicine, Institute of Clinical Pharmacology, Anhui Medical University, Hefei, Anhui Province, China
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9
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GPR125 (ADGRA3) is an autocleavable adhesion GPCR that traffics with Dlg1 to the basolateral membrane and regulates epithelial apico-basal polarity. J Biol Chem 2022; 298:102475. [PMID: 36089063 PMCID: PMC9539791 DOI: 10.1016/j.jbc.2022.102475] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2022] [Revised: 08/30/2022] [Accepted: 09/02/2022] [Indexed: 01/12/2023] Open
Abstract
The adhesion family of G protein–coupled receptors (GPCRs) is defined by an N-terminal large extracellular region that contains various adhesion-related domains and a highly-conserved GPCR-autoproteolysis-inducing (GAIN) domain, the latter of which is located immediately before a canonical seven-transmembrane domain. These receptors are expressed widely and involved in various functions including development, angiogenesis, synapse formation, and tumorigenesis. GPR125 (ADGRA3), an orphan adhesion GPCR, has been shown to modulate planar cell polarity in gastrulating zebrafish, but its biochemical properties and role in mammalian cells have remained largely unknown. Here, we show that human GPR125 likely undergoes cis-autoproteolysis when expressed in canine kidney epithelial MDCK cells and human embryonic kidney HEK293 cells. The cleavage appears to occur at an atypical GPCR proteolysis site within the GAIN domain during an early stage of receptor biosynthesis. The products, i.e., the N-terminal and C-terminal fragments, seem to remain associated after self-proteolysis, as observed in other adhesion GPCRs. Furthermore, in polarized MDCK cells, GPR125 is exclusively recruited to the basolateral domain of the plasma membrane. The recruitment likely requires the C-terminal PDZ-domain–binding motif of GPR125 and its interaction with the cell polarity protein Dlg1. Knockdown of GPR125 as well as that of Dlg1 results in formation of aberrant cysts with multiple lumens in Matrigel 3D culture of MDCK cells. Consistent with the multilumen phenotype, mitotic spindles are incorrectly oriented during cystogenesis in GPR125-KO MDCK cells. Thus, the basolateral protein GPR125, an autocleavable adhesion GPCR, appears to play a crucial role in apicobasal polarization in epithelial cells.
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10
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Sheldon H, Zhang W, Bridges E, Ang KH, Lin S, Masiero M, Li D, Handford PA, Whiteman P, Fischer R, Buffa F, Vatish M, Banham AH, Harris AL. ELTD1 is present in extracellular vesicles derived from endothelial cells as a cleaved extracellular domain which induces in vivo angiogenesis. JOURNAL OF EXTRACELLULAR BIOLOGY 2022; 1:e52. [PMID: 38939053 PMCID: PMC11080856 DOI: 10.1002/jex2.52] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Revised: 06/27/2022] [Accepted: 06/29/2022] [Indexed: 06/29/2024]
Abstract
ELTD1/ADGRL4 is an adhesion GPCR with an important role in angiogenesis. We recently identified a role for ELTD1 in wound repair and inflammation. Activation of ELTD1 in endothelial cells results in a type II EMT to myofibroblast-like cells that have enhanced angiogenic ability. Furthermore, expression of Eltd1 in murine breast cancer cells increases tumour growth by increasing blood vessel size and perfusion and by creating an immunosuppressive microenvironment. As extracellular vesicles (EVs) are known to be involved in vascular development, growth and maturation we investigated the composition and functional effects of the EVs isolated from ELTD1 expressing cells to elucidate their role in these processes. A highly glycosylated form of the extracellular domain (ECD) of ELTD1 is readily incorporated into EVs. Using mass spectrometry-based proteomics we identified proteins that are enriched in ELTD1-EVs and are involved in haemostasis and immune responses. ELTD1 enriched EVs were pro-angiogenic in vivo and in vitro and the presence of the ECD alone induced endothelial sprouting. In endothelial cells experiencing laminar flow, ELTD1 levels were reduced in the EVs when they are quiescent, showing a relationship between ELTD1 and the activation state of the endothelium. Using FACS, we detected a significant increase in vesicular ELTD1 in the plasma of patients with preeclampsia, a condition characterized by endothelial dysfunction. These data confirm a role for ELTD1 in wound repair and inflammation and reveal its potential as a biomarker of vessel dysfunction.
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Affiliation(s)
- Helen Sheldon
- Cancer Research UK Molecular Oncology LaboratoriesWeatherall Institute of Molecular MedicineUniversity of OxfordJohn Radcliffe HospitalOxfordUK
| | - Wei Zhang
- Nuffield Department of Women's & Reproductive Health, Women's CentreUniversity of OxfordJohn Radcliffe HospitalOxfordUK
| | - Esther Bridges
- Cancer Research UK Molecular Oncology LaboratoriesWeatherall Institute of Molecular MedicineUniversity of OxfordJohn Radcliffe HospitalOxfordUK
| | - Koon Hwee Ang
- Cancer Research UK Molecular Oncology LaboratoriesWeatherall Institute of Molecular MedicineUniversity of OxfordJohn Radcliffe HospitalOxfordUK
| | - Salwa Lin
- Cancer Research UK Molecular Oncology LaboratoriesWeatherall Institute of Molecular MedicineUniversity of OxfordJohn Radcliffe HospitalOxfordUK
| | - Massimo Masiero
- Nuffield Division of Clinical Laboratory SciencesRadcliffe Department of MedicineJohn Radcliffe HospitalOxfordUK
| | - Demin Li
- Nuffield Division of Clinical Laboratory SciencesRadcliffe Department of MedicineJohn Radcliffe HospitalOxfordUK
| | | | - Pat Whiteman
- Department of BiochemistryUniversity of OxfordOxfordUK
| | - Roman Fischer
- Nuffield Department of MedicineTarget Discovery InstituteOxford University, NDM Research BuildingOxfordUK
| | - Francesca Buffa
- Department of OncologyUniversity of OxfordChurchill HospitalOxfordUK
| | - Manu Vatish
- Nuffield Department of Women's & Reproductive Health, Women's CentreUniversity of OxfordJohn Radcliffe HospitalOxfordUK
| | - Alison H. Banham
- Nuffield Division of Clinical Laboratory SciencesRadcliffe Department of MedicineJohn Radcliffe HospitalOxfordUK
| | - Adrian L. Harris
- Cancer Research UK Molecular Oncology LaboratoriesWeatherall Institute of Molecular MedicineUniversity of OxfordJohn Radcliffe HospitalOxfordUK
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11
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Adhesion GPCR GPR56 Expression Profiling in Human Tissues. Cells 2021; 10:cells10123557. [PMID: 34944065 PMCID: PMC8700376 DOI: 10.3390/cells10123557] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Revised: 12/08/2021] [Accepted: 12/13/2021] [Indexed: 12/01/2022] Open
Abstract
Despite the immense functional relevance of GPR56 (gene ADGRG1) in highly diverse (patho)physiological processes such as tumorigenesis, immune regulation, and brain development, little is known about its exact tissue localization. Here, we validated antibodies for GPR56-specific binding using cells with tagged GPR56 or eliminated ADGRG1 in immunotechniques. Using the most suitable antibody, we then established the human GPR56 tissue expression profile. Overall, ADGRG1 RNA-sequencing data of human tissues and GPR56 protein expression correlate very well. In the adult brain especially, microglia are GPR56-positive. Outside the central nervous system, GPR56 is frequently expressed in cuboidal or highly prismatic secreting epithelia. High ADGRG1 mRNA, present in the thyroid, kidney, and placenta is related to elevated GPR56 in thyrocytes, kidney tubules, and the syncytiotrophoblast, respectively. GPR56 often appears in association with secreted proteins such as pepsinogen A in gastric chief cells and insulin in islet β-cells. In summary, GPR56 shows a broad, not cell-type restricted expression in humans.
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12
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The role of GPR56/ADGRG1 in health and disease. Biomed J 2021; 44:534-547. [PMID: 34654683 PMCID: PMC8640549 DOI: 10.1016/j.bj.2021.04.012] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2021] [Revised: 04/27/2021] [Accepted: 04/28/2021] [Indexed: 12/12/2022] Open
Abstract
GPR56/ADGRG1 is a versatile adhesion G protein-coupled receptor important in the physiological functions of the central and peripheral nervous systems, reproductive system, muscle hypertrophy, immune regulation, and hematopoietic stem cell generation. By contrast, aberrant expression or deregulated functions of GPR56 have been implicated in diverse pathological processes, including bilateral frontoparietal polymicrogyria, depression, and tumorigenesis. In this review article, we summarize and discuss the current understandings of the role of GPR56 in health and disease.
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13
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Abstract
Background Members of the adhesion family of G protein-coupled receptors (GPCRs) have received attention for their roles in health and disease, including cancer. Over the past decade, several members of the family have been implicated in the pathogenesis of glioblastoma. Methods Here, we discuss the basic biology of adhesion GPCRs and review in detail specific members of the receptor family with known functions in glioblastoma. Finally, we discuss the potential use of adhesion GPCRs as novel treatment targets in neuro-oncology.
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Affiliation(s)
- Gabriele Stephan
- Department of Neurosurgery, NYU Grossman School of Medicine, New York, New York, USA
| | - Niklas Ravn-Boess
- Department of Neurosurgery, NYU Grossman School of Medicine, New York, New York, USA
| | - Dimitris G Placantonakis
- Department of Neurosurgery, NYU Grossman School of Medicine, New York, New York, USA.,Kimmel Center for Stem Cell Biology, NYU Grossman School of Medicine, New York, New York, USA.,Laura and Isaac Perlmutter Cancer Center, NYU Grossman School of Medicine, New York, New York, USA.,Brain and Spine Tumor Center, NYU Grossman School of Medicine, New York, New York, USA.,Neuroscience Institute, NYU Grossman School of Medicine, New York, New York, USA
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14
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Ganesh RA, Venkataraman K, Sirdeshmukh R. GPR56: An adhesion GPCR involved in brain development, neurological disorders and cancer. Brain Res 2020; 1747:147055. [PMID: 32798453 DOI: 10.1016/j.brainres.2020.147055] [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: 02/14/2020] [Revised: 07/04/2020] [Accepted: 08/11/2020] [Indexed: 12/15/2022]
Abstract
GPR56/ADGRG1 is a member of the adhesion G-protein coupled receptor (aGPCR) family and one of the important players in the normal development of the brain. It plays a pivotal role in the diverse neurobiological processes, including cortical formation, oligodendrocyte development, and myelination. Mutations in GPR56 are known to cause brain malformation, myelination defects and are also implied in many cancers, including brain tumors. Since its identification almost two decades ago, GPR56 has emerged from an orphaned and uncharacterized GPCR to an increasingly well studied receptor. Yet, much needs to be understood about GPR56, both in terms of its molecular interactions and biological functions that may be relevant in normal health and disease. The review is focussed on the recent available knowledge of GPR56, which would give useful insights into its known and potential roles in the human brain, neurological disorders, and brain tumors like glioblastoma.
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Affiliation(s)
- Raksha A Ganesh
- Mazumdar Shaw Center for Translational Research, Narayana Health, Bangalore 560099, India; Center for Bio-Separation Technology, Vellore Institute of Technology, Vellore 632104, India
| | - Krishnan Venkataraman
- Center for Bio-Separation Technology, Vellore Institute of Technology, Vellore 632104, India
| | - Ravi Sirdeshmukh
- Mazumdar Shaw Center for Translational Research, Narayana Health, Bangalore 560099, India; Institute of Bioinformatics, International Tech Park, Bangalore 560066, India; Manipal Academy of Higher Education, Manipal 576104, India.
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15
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Vizurraga A, Adhikari R, Yeung J, Yu M, Tall GG. Mechanisms of adhesion G protein-coupled receptor activation. J Biol Chem 2020; 295:14065-14083. [PMID: 32763969 DOI: 10.1074/jbc.rev120.007423] [Citation(s) in RCA: 88] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Revised: 07/31/2020] [Indexed: 12/19/2022] Open
Abstract
Adhesion G protein-coupled receptors (AGPCRs) are a thirty-three-member subfamily of Class B GPCRs that control a wide array of physiological processes and are implicated in disease. AGPCRs uniquely contain large, self-proteolyzing extracellular regions that range from hundreds to thousands of residues in length. AGPCR autoproteolysis occurs within the extracellular GPCR autoproteolysis-inducing (GAIN) domain that is proximal to the N terminus of the G protein-coupling seven-transmembrane-spanning bundle. GAIN domain-mediated self-cleavage is constitutive and produces two-fragment holoreceptors that remain bound at the cell surface. It has been of recent interest to understand how AGPCRs are activated in relation to their two-fragment topologies. Dissociation of the AGPCR fragments stimulates G protein signaling through the action of the tethered-peptide agonist stalk that is occluded within the GAIN domain in the holoreceptor form. AGPCRs can also signal independently of fragment dissociation, and a few receptors possess GAIN domains incapable of self-proteolysis. This has resulted in complex theories as to how these receptors are activated in vivo, complicating pharmacological advances. Currently, there is no existing structure of an activated AGPCR to support any of the theories. Further confounding AGPCR research is that many of the receptors remain orphans and lack identified activating ligands. In this review, we provide a detailed layout of the current theorized modes of AGPCR activation with discussion of potential parallels to mechanisms used by other GPCR classes. We provide a classification means for the ligands that have been identified and discuss how these ligands may activate AGPCRs in physiological contexts.
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Affiliation(s)
- Alexander Vizurraga
- Department of Pharmacology, University of Michigan School of Medicine, Ann Arbor, Michigan, USA
| | - Rashmi Adhikari
- Department of Pharmacology, University of Michigan School of Medicine, Ann Arbor, Michigan, USA
| | - Jennifer Yeung
- Department of Pharmacology, University of Michigan School of Medicine, Ann Arbor, Michigan, USA
| | - Maiya Yu
- Department of Pharmacology, University of Michigan School of Medicine, Ann Arbor, Michigan, USA
| | - Gregory G Tall
- Department of Pharmacology, University of Michigan School of Medicine, Ann Arbor, Michigan, USA
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16
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Maser RL, Calvet JP. Adhesion GPCRs as a paradigm for understanding polycystin-1 G protein regulation. Cell Signal 2020; 72:109637. [PMID: 32305667 DOI: 10.1016/j.cellsig.2020.109637] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Revised: 04/12/2020] [Accepted: 04/13/2020] [Indexed: 12/21/2022]
Abstract
Polycystin-1, whose mutation is the most frequent cause of autosomal dominant polycystic kidney disease, is an extremely large and multi-faceted membrane protein whose primary or proximal cyst-preventing function remains undetermined. Accumulating evidence supports the idea that modulation of cellular signaling by heterotrimeric G proteins is a critical function of polycystin-1. The presence of a cis-autocatalyzed, G protein-coupled receptor (GPCR) proteolytic cleavage site, or GPS, in its extracellular N-terminal domain immediately preceding the first transmembrane domain is one of the notable conserved features of the polycystin-1-like protein family, and also of the family of cell adhesion GPCRs. Adhesion GPCRs are one of five families within the GPCR superfamily and are distinguished by a large N-terminal extracellular region consisting of multiple adhesion modules with a GPS-containing GAIN domain and bimodal functions in cell adhesion and signal transduction. Recent advances from studies of adhesion GPCRs provide a new paradigm for unraveling the mechanisms by which polycystin-1-associated G protein signaling contributes to the pathogenesis of polycystic kidney disease. This review highlights the structural and functional features shared by polycystin-1 and the adhesion GPCRs and discusses the implications of such similarities for our further understanding of the functions of this complicated protein.
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Affiliation(s)
- Robin L Maser
- Department of Clinical Laboratory Sciences, University of Kansas Medical Center, 3901 Rainbow Blvd., Kansas City, Kansas 66160, USA; Department of Biochemistry and Molecular Biology, University of Kansas Medical Center, 3901 Rainbow Blvd., Kansas City, Kansas 66160, USA; Jared Grantham Kidney Institute, University of Kansas Medical Center, 3901 Rainbow Blvd., Kansas City, Kansas 66160, USA.
| | - James P Calvet
- Department of Biochemistry and Molecular Biology, University of Kansas Medical Center, 3901 Rainbow Blvd., Kansas City, Kansas 66160, USA; Jared Grantham Kidney Institute, University of Kansas Medical Center, 3901 Rainbow Blvd., Kansas City, Kansas 66160, USA.
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17
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Synaptamide activates the adhesion GPCR GPR110 (ADGRF1) through GAIN domain binding. Commun Biol 2020; 3:109. [PMID: 32144388 PMCID: PMC7060178 DOI: 10.1038/s42003-020-0831-6] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Accepted: 02/07/2020] [Indexed: 02/07/2023] Open
Abstract
Adhesion G protein-coupled receptors (aGPCR) are characterized by a large extracellular region containing a conserved GPCR-autoproteolysis-inducing (GAIN) domain. Despite their relevance to several disease conditions, we do not understand the molecular mechanism by which aGPCRs are physiologically activated. GPR110 (ADGRF1) was recently deorphanized as the functional receptor of N-docosahexaenoylethanolamine (synaptamide), a potent synaptogenic metabolite of docosahexaenoic acid. Thus far, synaptamide is the first and only small-molecule endogenous ligand of an aGPCR. Here, we demonstrate the molecular basis of synaptamide-induced activation of GPR110 in living cells. Using in-cell chemical cross-linking/mass spectrometry, computational modeling and mutagenesis-assisted functional assays, we discover that synaptamide specifically binds to the interface of GPR110 GAIN subdomains through interactions with residues Q511, N512 and Y513, causing an intracellular conformational change near TM6 that triggers downstream signaling. This ligand-induced GAIN-targeted activation mechanism provides a framework for understanding the physiological function of aGPCRs and therapeutic targeting in the GAIN domain. Huang et al clarify the molecular mechanism of activation of adhesion G protein-coupled receptor GPR110 by synaptamide, the only small-molecule endogenous ligand known for this class of GPCR. They find through chemical cross-linking mass spectrometry, modeling and mutagenesis that synaptamide binds to residues in the GAIN domain and induces a conformational change triggering downstream signaling.
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18
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Zhu B, Luo R, Jin P, Li T, Oak HC, Giera S, Monk KR, Lak P, Shoichet BK, Piao X. GAIN domain-mediated cleavage is required for activation of G protein-coupled receptor 56 (GPR56) by its natural ligands and a small-molecule agonist. J Biol Chem 2019; 294:19246-19254. [PMID: 31628191 DOI: 10.1074/jbc.ra119.008234] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Revised: 10/02/2019] [Indexed: 12/15/2022] Open
Abstract
Adhesion G protein-coupled receptors (aGPCRs) represent a distinct family of GPCRs that regulate several developmental and physiological processes. Most aGPCRs undergo GPCR autoproteolysis-inducing domain-mediated protein cleavage, which produces a cryptic tethered agonist (termed Stachel (stinger)), and cleavage-dependent and -independent aGPCR signaling mechanisms have been described. aGPCR G1 (ADGRG1 or G protein-coupled receptor 56 (GPR56)) has pleiotropic functions in the development of multiple organ systems, which has broad implications for human diseases. To date, two natural GPR56 ligands, collagen III and tissue transglutaminase (TG2), and one small-molecule agonist, 3-α-acetoxydihydrodeoxygedunin (3-α-DOG), have been identified, in addition to a synthetic peptide, P19, that contains seven amino acids of the native Stachel sequence. However, the mechanisms by which these natural and small-molecule agonists signal through GPR56 remain unknown. Here we engineered a noncleavable receptor variant that retains signaling competence via the P19 peptide. We demonstrate that both natural and small-molecule agonists can activate only cleaved GPR56. Interestingly, TG2 required both receptor cleavage and the presence of a matrix protein, laminin, to activate GPR56, whereas collagen III and 3-α-DOG signaled without any cofactors. On the other hand, both TG2/laminin and collagen III activate the receptor by dissociating the N-terminal fragment from its C-terminal fragment, enabling activation by the Stachel sequence, whereas P19 and 3-α-DOG initiate downstream signaling without disengaging the N-terminal fragment from its C-terminal fragment. These findings deepen our understanding of how GPR56 signals via natural ligands, and a small-molecule agonist may be broadly applicable to other aGPCR family members.
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Affiliation(s)
- Beika Zhu
- Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, Weill Institute of Neuroscience, University of California, San Francisco, California 94143
| | - Rong Luo
- Department of Medicine, Children's Hospital and Harvard Medical School, Boston, Massachusetts 02115
| | - Peng Jin
- Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, Weill Institute of Neuroscience, University of California, San Francisco, California 94143
| | - Tao Li
- Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, Weill Institute of Neuroscience, University of California, San Francisco, California 94143
| | - Hayeon C Oak
- Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, Weill Institute of Neuroscience, University of California, San Francisco, California 94143
| | - Stefanie Giera
- Department of Medicine, Children's Hospital and Harvard Medical School, Boston, Massachusetts 02115
| | - Kelly R Monk
- Vollum Institute, Oregon Health and Science University, Portland, Oregon 97239
| | - Parnian Lak
- Department of Pharmaceutical Chemistry and Quantitative Biology Institute, University of California, San Francisco, California 94143
| | - Brian K Shoichet
- Department of Pharmaceutical Chemistry and Quantitative Biology Institute, University of California, San Francisco, California 94143
| | - Xianhua Piao
- Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, Weill Institute of Neuroscience, University of California, San Francisco, California 94143 .,Department of Medicine, Children's Hospital and Harvard Medical School, Boston, Massachusetts 02115.,Division of Neonatology, Department of Pediatrics, University of California, San Francisco, California 94158.,Newborn Brain Research Institute, University of California, San Francisco, California 94158
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19
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Adhesion G protein-coupled receptors: opportunities for drug discovery. Nat Rev Drug Discov 2019; 18:869-884. [PMID: 31462748 DOI: 10.1038/s41573-019-0039-y] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/18/2019] [Indexed: 12/24/2022]
Abstract
Adhesion G protein-coupled receptors (aGPCRs) - one of the five main families in the GPCR superfamily - have several atypical characteristics, including large, multi-domain N termini and a highly conserved region that can be autoproteolytically cleaved. Although GPCRs overall have well-established pharmacological tractability, currently no therapies that target any of the 33 members of the aGPCR family are either approved or in clinical trials. However, human genetics and preclinical research have strengthened the links between aGPCRs and disease in recent years. This, together with a greater understanding of their functional complexity, has led to growing interest in aGPCRs as drug targets. A framework for prioritizing aGPCR targets and supporting approaches to develop aGPCR modulators could therefore be valuable in harnessing the untapped therapeutic potential of this family. With this in mind, here we discuss the unique opportunities and challenges for drug discovery in modulating aGPCR functions, including target identification, target validation, assay development and safety considerations, using ADGRG1 as an illustrative example.
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20
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Zhang S, Chatterjee T, Godoy C, Wu L, Liu QJ, Carmon KS. GPR56 Drives Colorectal Tumor Growth and Promotes Drug Resistance through Upregulation of MDR1 Expression via a RhoA-Mediated Mechanism. Mol Cancer Res 2019; 17:2196-2207. [PMID: 31444231 DOI: 10.1158/1541-7786.mcr-19-0436] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2019] [Revised: 07/19/2019] [Accepted: 08/20/2019] [Indexed: 12/26/2022]
Abstract
Drug resistance continues to be a major obstacle of effective therapy for colorectal cancer, leading to tumor relapse or treatment failure. Cancer stem cells (CSC) or tumor-initiating cells are a subpopulation of tumor cells which retain the capacity for self-renewal and are suggested to be implicated in drug resistance. LGR5 is highly expressed in colorectal cancer and marks CSCs that drive tumor growth and metastasis. LGR5(+) CSCs cells were shown to interconvert with more drug-resistant LGR5(-) cancer cells, and treatment with LGR5-targeted antibody-drug conjugates (ADC) eliminated LGR5(+) tumors, yet a fraction of LGR5(-) tumors eventually recurred. Therefore, it is important to identify mechanisms associated with CSC plasticity and drug resistance in order to develop curative therapies. Here, we show that loss of LGR5 in colon cancer cells enhanced resistance to irinotecan and 5-fluorouracil and increased expression of adhesion G-protein-coupled receptor, GPR56. GPR56 expression was significantly higher in primary colon tumors versus matched normal tissues and correlated with poor survival outcome. GPR56 enhanced drug resistance through upregulation of MDR1 levels via a RhoA-mediated signaling mechanism. Loss of GPR56 led to suppression of tumor growth and increased sensitivity of cancer cells to chemotherapy and monomethyl auristatin E-linked anti-LGR5 ADCs, by reducing MDR1 levels. These findings suggest that upregulation of GPR56 may be a mechanism associated with CSC plasticity by which LGR5(-) cancer cells acquire a more drug-resistant phenotype. IMPLICATIONS: Our findings suggest that targeting GPR56 may provide a new strategy for the treatment of colorectal cancer and combatting drug resistance.
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Affiliation(s)
- Sheng Zhang
- Texas Therapeutics Institute, The Brown Foundation Institute of Molecular Medicine, University of Texas Health Science Center at Houston, Houston, Texas
| | - Treena Chatterjee
- Texas Therapeutics Institute, The Brown Foundation Institute of Molecular Medicine, University of Texas Health Science Center at Houston, Houston, Texas
| | - Carla Godoy
- Texas Therapeutics Institute, The Brown Foundation Institute of Molecular Medicine, University of Texas Health Science Center at Houston, Houston, Texas
| | - Ling Wu
- Texas Therapeutics Institute, The Brown Foundation Institute of Molecular Medicine, University of Texas Health Science Center at Houston, Houston, Texas
| | - Qingyun J Liu
- Texas Therapeutics Institute, The Brown Foundation Institute of Molecular Medicine, University of Texas Health Science Center at Houston, Houston, Texas
| | - Kendra S Carmon
- Texas Therapeutics Institute, The Brown Foundation Institute of Molecular Medicine, University of Texas Health Science Center at Houston, Houston, Texas.
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21
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Langenhan T. Adhesion G protein–coupled receptors—Candidate metabotropic mechanosensors and novel drug targets. Basic Clin Pharmacol Toxicol 2019; 126 Suppl 6:5-16. [DOI: 10.1111/bcpt.13223] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Accepted: 02/26/2019] [Indexed: 12/11/2022]
Affiliation(s)
- Tobias Langenhan
- Rudolf Schönheimer Institute of Biochemistry, Division of General Biochemistry, Medical Faculty Leipzig University Leipzig Germany
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22
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Huang KY, Lin HH. The Activation and Signaling Mechanisms of GPR56/ADGRG1 in Melanoma Cell. Front Oncol 2018; 8:304. [PMID: 30135857 PMCID: PMC6092491 DOI: 10.3389/fonc.2018.00304] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2017] [Accepted: 07/19/2018] [Indexed: 12/18/2022] Open
Abstract
Adhesion G protein-coupled receptors (aGPCRs) constitute the second largest GPCR subfamily. GPR56/ADGRG1 is a member of the ADGRG subgroup of aGPCRs. Although GPR56 is best known for its pivotal role in the cerebral cortical development, it is also important for tumor progression. Numerous studies have revealed that GPR56 is expressed in various cancer types with a role in cancer cell adhesion, migration and metastasis. In a recent study, we found that the immobilized GPR56-specific CG4 antibody enhanced IL-6 production and migration ability of melanoma cells. In this review, we will summarize the current understanding of GPR56 function and discuss the activation and signaling mechanisms of GPR56 in melanoma cells.
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Affiliation(s)
- Kuan-Yeh Huang
- Department of Microbiology and Immunology, College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Hsi-Hsien Lin
- Department of Microbiology and Immunology, College of Medicine, Chang Gung University, Taoyuan, Taiwan.,Department of Anatomic Pathology, Chang Gung Memorial Hospital-Linkou, Taoyuan, Taiwan.,Chang Gung Immunology Consortium, Chang Gung Memorial Hospital-Linkou, Taoyuan, Taiwan
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23
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Fine-Tuning Limited Proteolysis: A Major Role for Regulated Site-Specific O-Glycosylation. Trends Biochem Sci 2018; 43:269-284. [PMID: 29506880 DOI: 10.1016/j.tibs.2018.02.005] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2017] [Revised: 01/26/2018] [Accepted: 02/02/2018] [Indexed: 11/23/2022]
Abstract
Limited proteolytic processing is an essential and ubiquitous post-translational modification (PTM) affecting secreted proteins; failure to regulate the process is often associated with disease. Glycosylation is also a ubiquitous protein PTM and site-specific O-glycosylation in close proximity to sites of proteolysis can regulate and direct the activity of proprotein convertases, a disintegrin and metalloproteinases (ADAMs), and metalloproteinases affecting the activation or inactivation of many classes of proteins, including G-protein-coupled receptors (GPCRs). Here, we summarize the emerging data that suggest O-glycosylation to be a key regulator of limited proteolysis, and highlight the potential for crosstalk between multiple PTMs.
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24
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Speca DJ, Trimmer JS, Peterson AS, Díaz E. Whole exome sequencing reveals a functional mutation in the GAIN domain of the Bai2 receptor underlying a forward mutagenesis hyperactivity QTL. Mamm Genome 2017; 28:465-475. [PMID: 28894906 PMCID: PMC5702255 DOI: 10.1007/s00335-017-9716-5] [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: 07/07/2017] [Accepted: 09/05/2017] [Indexed: 10/18/2022]
Abstract
The identification of novel genes underlying complex mouse behavioral traits remains an important step in understanding normal brain function and its dysfunction in mental health disorders. To identify dominant mutations that influence locomotor activity, we performed a mouse N-ethyl-N-nitrosourea (ENU) forward mutagenesis screen and mapped several loci as quantitative traits. Here we describe the fine-mapping and positional cloning of a hyperactivity locus mapped to the medial portion of mouse chromosome four. We employed a modified recombinant progeny testing approach to fine-map the confidence interval from ≈20 Mb down to ≈5 Mb. Whole exome resequencing of all exons in this region revealed a single missense mutation in the adhesion G protein-coupled receptor brain-specific angiogenesis inhibitor 2 (Bai2). This mutation, R619W, is located in a critical extracellular domain that is a hotspot for mutations in this receptor class. We find that in two different mammalian cell lines, surface expression of Bai2 R619W is markedly reduced relative to wild-type Bai2, suggesting that R619W is a loss-of-function mutation. Our results highlight the powerful combination of ENU mutagenesis and next-generation sequencing to identify specific mutations that manifest as subtle behavioral phenotypes.
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Affiliation(s)
- David J Speca
- Department of Pharmacology, University of California, Davis, CA, 95616, USA.
| | - James S Trimmer
- Department of Neurobiology, Physiology and Behavior, University of California, Davis, CA, 95616, USA
- Department of Physiology and Membrane Biology, University of California, Davis, CA, 95616, USA
| | - Andrew S Peterson
- Department of Molecular Biology, Genentech, South San Francisco, CA, 94080, USA
| | - Elva Díaz
- Department of Pharmacology, University of California, Davis, CA, 95616, USA
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25
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Salzman GS, Ackerman SD, Ding C, Koide A, Leon K, Luo R, Stoveken HM, Fernandez CG, Tall GG, Piao X, Monk KR, Koide S, Araç D. Structural Basis for Regulation of GPR56/ADGRG1 by Its Alternatively Spliced Extracellular Domains. Neuron 2017; 91:1292-1304. [PMID: 27657451 DOI: 10.1016/j.neuron.2016.08.022] [Citation(s) in RCA: 80] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2016] [Revised: 06/15/2016] [Accepted: 07/25/2016] [Indexed: 11/18/2022]
Abstract
Adhesion G protein-coupled receptors (aGPCRs) play critical roles in diverse neurobiological processes including brain development, synaptogenesis, and myelination. aGPCRs have large alternatively spliced extracellular regions (ECRs) that likely mediate intercellular signaling; however, the precise roles of ECRs remain unclear. The aGPCR GPR56/ADGRG1 regulates both oligodendrocyte and cortical development. Accordingly, human GPR56 mutations cause myelination defects and brain malformations. Here, we determined the crystal structure of the GPR56 ECR, the first structure of any complete aGPCR ECR, in complex with an inverse-agonist monobody, revealing a GPCR-Autoproteolysis-Inducing domain and a previously unidentified domain that we term Pentraxin/Laminin/neurexin/sex-hormone-binding-globulin-Like (PLL). Strikingly, PLL domain deletion caused increased signaling and characterizes a GPR56 splice variant. Finally, we show that an evolutionarily conserved residue in the PLL domain is critical for oligodendrocyte development in vivo. Thus, our results suggest that the GPR56 ECR has unique and multifaceted regulatory functions, providing novel insights into aGPCR roles in neurobiology.
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Affiliation(s)
- Gabriel S Salzman
- Biophysical Sciences Program, The University of Chicago, Chicago, IL 60637, USA; Medical Scientist Training Program, The University of Chicago, Chicago, IL 60637, USA; Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, IL 60637, USA
| | - Sarah D Ackerman
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Chen Ding
- Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, IL 60637, USA
| | - Akiko Koide
- Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, IL 60637, USA
| | - Katherine Leon
- Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, IL 60637, USA
| | - Rong Luo
- Division of Newborn Medicine, Department of Medicine, Boston Children's Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - Hannah M Stoveken
- Departments of Pharmacology and Physiology, University of Rochester Medical Center, Rochester, NY 14642, USA
| | - Celia G Fernandez
- Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, IL 60637, USA
| | - Gregory G Tall
- Departments of Pharmacology and Physiology, University of Rochester Medical Center, Rochester, NY 14642, USA
| | - Xianhua Piao
- Division of Newborn Medicine, Department of Medicine, Boston Children's Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - Kelly R Monk
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Shohei Koide
- Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, IL 60637, USA.
| | - Demet Araç
- Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, IL 60637, USA.
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26
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Abstract
The adhesion G protein-coupled receptors (aGPCRs) are an evolutionarily ancient family of receptors that play key roles in many different physiological processes. These receptors are notable for their exceptionally long ectodomains, which span several hundred to several thousand amino acids and contain various adhesion-related domains, as well as a GPCR autoproteolysis-inducing (GAIN) domain. The GAIN domain is conserved throughout almost the entire family and undergoes autoproteolysis to cleave the receptors into two noncovalently-associated protomers. Recent studies have revealed that the signaling activity of aGPCRs is largely determined by changes in the interactions among these protomers. We review recent advances in understanding aGPCR activation mechanisms and discuss the physiological roles and pharmacological properties of aGPCRs, with an eye toward the potential utility of these receptors as drug targets.
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Affiliation(s)
- Ryan H Purcell
- Department of Pharmacology, Emory University School of Medicine, Atlanta, Georgia, 30322, USA;
| | - Randy A Hall
- Department of Pharmacology, Emory University School of Medicine, Atlanta, Georgia, 30322, USA;
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27
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High levels of soluble GPR56/ADGRG1 are associated with positive rheumatoid factor and elevated tumor necrosis factor in patients with rheumatoid arthritis. JOURNAL OF MICROBIOLOGY, IMMUNOLOGY, AND INFECTION = WEI MIAN YU GAN RAN ZA ZHI 2017; 51:485-491. [PMID: 28690029 DOI: 10.1016/j.jmii.2016.11.010] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2016] [Revised: 09/26/2016] [Accepted: 11/07/2016] [Indexed: 12/14/2022]
Abstract
BACKGROUND GPR56/ADGRG1 is a member of the adhesion-class G protein-coupled receptor (aGPCR) family important in brain development, oncogenesis and tumor metastasis. Like other aGPCRs, GPR56 is cleaved at the GPCR proteolysis site (GPS) motif into an N-terminal fragment (NTF) and a C-terminal fragment (CTF). Existence of soluble GPR56 (sGPR56) has been shown in vitro, however the underlying mechanism and its pathophysiologic role remains undetermined. OBJECTIVE To assess the presence of sGPR56 in human serum using ELISA assay and compare the serum sGPR56 levels among patients of various chronic inflammatory diseases and healthy subjects. PATIENTS AND METHODS In this study, serum samples from patients with systemic lupus erythematosus (SLE) (n = 57), rheumatoid arthritis (RA) (n = 95), Sjögren's syndrome (SS) (n = 29), ankylosing spondylitis (AS) (n = 51), and normal controls (n = 81) were analyzed using sGPR56-specific ELISA. RESULT We show that serum sGPR56 levels are increased in patients of RA, but not in those with SLE, SS and AS. Intriguingly, serum sGPR56 levels in RA patients correlated with positive rheumatoid factor, a marker of bone erosion and poor outcome. In addition, an elevated sGPR56 level is also noted in RA patients with higher tumor necrosis factor level. CONCLUSION we conclude that sGPR56 is present in vivo and sGPR56 level is elevated in certain chronic inflammatory diseases such as RA. Hence, sGPR56 might be considered a potential biomarker for RA disease progression.
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Kishore A, Hall RA. Disease-associated extracellular loop mutations in the adhesion G protein-coupled receptor G1 (ADGRG1; GPR56) differentially regulate downstream signaling. J Biol Chem 2017; 292:9711-9720. [PMID: 28424266 DOI: 10.1074/jbc.m117.780551] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2017] [Revised: 04/17/2017] [Indexed: 12/31/2022] Open
Abstract
Mutations to the adhesion G protein-coupled receptor ADGRG1 (G1; also known as GPR56) underlie the neurological disorder bilateral frontoparietal polymicrogyria. Disease-associated mutations in G1 studied to date are believed to induce complete loss of receptor function through disruption of either receptor trafficking or signaling activity. Given that N-terminal truncation of G1 and other adhesion G protein-coupled receptors has been shown to significantly increase the receptors' constitutive signaling, we examined two different bilateral frontoparietal polymicrogyria-inducing extracellular loop mutations (R565W and L640R) in the context of both full-length and N-terminally truncated (ΔNT) G1. Interestingly, we found that these mutations reduced surface expression of full-length G1 but not G1-ΔNT in HEK-293 cells. Moreover, the mutations ablated receptor-mediated activation of serum response factor luciferase, a classic measure of Gα12/13-mediated signaling, but had no effect on G1-mediated signaling to nuclear factor of activated T cells (NFAT) luciferase. Given these differential signaling results, we sought to further elucidate the pathway by which G1 can activate NFAT luciferase. We found no evidence that ΔNT activation of NFAT is dependent on Gαq/11-mediated or β-arrestin-mediated signaling but rather involves liberation of Gβγ subunits and activation of calcium channels. These findings reveal that disease-associated mutations to the extracellular loops of G1 differentially alter receptor trafficking, depending on the presence of the N terminus, and differentially alter signaling to distinct downstream pathways.
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Affiliation(s)
- Ayush Kishore
- From the Department of Pharmacology, Emory University School of Medicine, Atlanta, Georgia 30322
| | - Randy A Hall
- From the Department of Pharmacology, Emory University School of Medicine, Atlanta, Georgia 30322
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29
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Vandervore L, Stouffs K, Tanyalçin I, Vanderhasselt T, Roelens F, Holder-Espinasse M, Jørgensen A, Pepin MG, Petit F, Khau Van Kien P, Bahi-Buisson N, Lissens W, Gheldof A, Byers PH, Jansen AC. Bi-allelic variants in COL3A1 encoding the ligand to GPR56 are associated with cobblestone-like cortical malformation, white matter changes and cerebellar cysts. J Med Genet 2017; 54:432-440. [PMID: 28258187 DOI: 10.1136/jmedgenet-2016-104421] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2016] [Revised: 01/17/2017] [Accepted: 01/19/2017] [Indexed: 12/24/2022]
Abstract
BACKGROUND Collagens are one of the major constituents of the pial membrane, which plays a crucial role in neuronal migration and cortical lamination during brain development. Type III procollagen, the chains of which are encoded by COL3A1, is the ligand of the G protein-coupled receptor 56 (GPR56), also known as adhesion G protein-coupled receptor G1. Bi-allelic mutations in GPR56 give rise to cobblestone-like malformation, white matter changes and cerebellar dysplasia. This report shows that bi-allelic mutations in COL3A1 are associated with a similar phenotype. METHODS Exome analysis was performed in a family consisting of two affected and two non-affected siblings. Brain imaging studies of this family and of two previously reported individuals with bi-allelic mutations in COL3A1 were reviewed. Functional assays were performed on dermal fibroblasts. RESULTS Exome analysis revealed a novel homozygous variant c.145C>G (p.Pro49Ala) in exon 2 of COL3A1. Brain MRI in the affected siblings as well as in the two previously reported individuals with bi-allelic COL3A1 mutations showed a brain phenotype similar to that associated with mutations in GPR56. CONCLUSION Homozygous or compound heterozygous mutations in COL3A1 are associated with cobblestone-like malformation in all three families reported to date. The variability of the phenotype across patients suggests that genetic alterations in distinct domains of type III procollagen can lead to different outcomes. The presence of cobblestone-like malformation in patients with bi-allelic COL3A1 mutations emphasises the critical role of the type III collagen-GPR56 axis and the pial membrane in the regulation of brain development and cortical lamination.
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Affiliation(s)
- Laura Vandervore
- Neurogenetics Research Group, Research Cluster Reproduction, Genetics and Regenerative Medicine, Vrije Universiteit Brussel, Brussels, Belgium.,Center for Medical Genetics, UZ Brussel, Brussels, Belgium
| | - Katrien Stouffs
- Neurogenetics Research Group, Research Cluster Reproduction, Genetics and Regenerative Medicine, Vrije Universiteit Brussel, Brussels, Belgium.,Center for Medical Genetics, UZ Brussel, Brussels, Belgium
| | - Ibrahim Tanyalçin
- Neurogenetics Research Group, Research Cluster Reproduction, Genetics and Regenerative Medicine, Vrije Universiteit Brussel, Brussels, Belgium.,Center for Medical Genetics, UZ Brussel, Brussels, Belgium
| | | | - Filip Roelens
- Department of Pediatric Neurology, AZ Delta, Roeselare, Belgium
| | | | - Agnete Jørgensen
- Division of Child and Adolescent Health, Department of Medical Genetics, University Hospital of North Norway, Tromsø, Norway
| | - Melanie G Pepin
- Department of Pathology, University of Washington, Seattle, Washington, USA
| | - Florence Petit
- Service de Génétique Clinique, Hôpital J. de Flandre, Lille, France
| | | | - Nadia Bahi-Buisson
- Institut Imagine, Université Paris Descartes - Sorbonne Paris Cités, Paris, France
| | - Willy Lissens
- Neurogenetics Research Group, Research Cluster Reproduction, Genetics and Regenerative Medicine, Vrije Universiteit Brussel, Brussels, Belgium.,Center for Medical Genetics, UZ Brussel, Brussels, Belgium
| | - Alexander Gheldof
- Neurogenetics Research Group, Research Cluster Reproduction, Genetics and Regenerative Medicine, Vrije Universiteit Brussel, Brussels, Belgium.,Center for Medical Genetics, UZ Brussel, Brussels, Belgium
| | - Peter H Byers
- Department of Pathology, University of Washington, Seattle, Washington, USA.,Department of Medicine (Medical Genetics), University of Washington, Seattle, USA
| | - Anna C Jansen
- Neurogenetics Research Group, Research Cluster Reproduction, Genetics and Regenerative Medicine, Vrije Universiteit Brussel, Brussels, Belgium.,Department of Pediatrics, Pediatric Neurology Unit, UZ Brussel, Brussels, Belgium
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30
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Chiang NY, Peng YM, Juang HH, Chen TC, Pan HL, Chang GW, Lin HH. GPR56/ADGRG1 Activation Promotes Melanoma Cell Migration via NTF Dissociation and CTF-Mediated Gα 12/13/RhoA Signaling. J Invest Dermatol 2016; 137:727-736. [PMID: 27818281 DOI: 10.1016/j.jid.2016.10.031] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2016] [Revised: 10/06/2016] [Accepted: 10/17/2016] [Indexed: 02/07/2023]
Abstract
GPR56/ADGRG1 is a versatile adhesion G protein-coupled receptor with diverse biological functions. GPR56 expression is variably detected in human melanoma cell lines and correlates inversely with the metastatic potential of melanoma lesions. GPR56 associates with the tetraspanins CD9 and CD81 on the melanoma cell surface. GPR56 activation by immobilized CG4 monoclonal antibody facilitates N-terminal fragment dissociation in a CD9/CD81-dependent manner specifically inducing IL-6 production, which promotes cell migration and invasion. Interestingly, expression of GPR56-C-terminal fragment alone recapitulates the antibody-induced receptor function, implicating a major role for the C-terminal fragment in GPR56 activation and signaling. Analysis of site-directed mutant receptors attests the importance of the conserved N-terminal residues of the C-terminal fragment for its self-activation. Finally, we show that the GPR56-induced signaling in melanoma cells is mediated by the Gα12/13/RhoA pathway. In summary, the expression and activation of GPR56 may modulate melanoma progression in part by inducing IL-6 production after N-terminal fragment dissociation and C-terminal fragment self-activation.
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Affiliation(s)
- Nien-Yi Chiang
- Department of Microbiology and Immunology, Chang Gung University, Taoyuan, Taiwan
| | - Yen-Ming Peng
- Graduate Institute of Biomedical Sciences, Chang Gung University, Taoyuan, Taiwan
| | - Horng-Heng Juang
- Graduate Institute of Biomedical Sciences, Chang Gung University, Taoyuan, Taiwan; Department of Anatomy, College of Medicine, Chang Gung University, Taoyuan, Taiwan; Department of Urology, Chang Gung Memorial Hospital-Linkou, Taoyuan, Taiwan
| | - Tse-Ching Chen
- Department of Anatomic Pathology, Chang Gung Memorial Hospital-Linkou, Taoyuan, Taiwan
| | - Hsiao-Lin Pan
- Graduate Institute of Biomedical Sciences, Chang Gung University, Taoyuan, Taiwan
| | - Gin-Wen Chang
- Department of Microbiology and Immunology, Chang Gung University, Taoyuan, Taiwan
| | - Hsi-Hsien Lin
- Department of Microbiology and Immunology, Chang Gung University, Taoyuan, Taiwan; Graduate Institute of Biomedical Sciences, Chang Gung University, Taoyuan, Taiwan; Department of Anatomic Pathology, Chang Gung Memorial Hospital-Linkou, Taoyuan, Taiwan; Chang Gung Immunology Consortium, Chang Gung Memorial Hospital and Chang Gung University, Taoyuan, Taiwan.
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31
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Orphan GPR110 (ADGRF1) targeted by N-docosahexaenoylethanolamine in development of neurons and cognitive function. Nat Commun 2016; 7:13123. [PMID: 27759003 PMCID: PMC5075789 DOI: 10.1038/ncomms13123] [Citation(s) in RCA: 93] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Accepted: 09/05/2016] [Indexed: 12/27/2022] Open
Abstract
Docosahexaenoic acid (DHA, 22:6n-3) is an omega-3 fatty acid essential for proper brain development. N-docosahexaenoylethanolamine (synaptamide), an endogenous metabolite of DHA, potently promotes neurogenesis, neuritogenesis and synaptogenesis; however, the underlying molecular mechanism is not known. Here, we demonstrate orphan G-protein coupled receptor 110 (GPR110, ADGRF1) as the synaptamide receptor, mediating synaptamide-induced bioactivity in a cAMP-dependent manner. Mass spectrometry-based proteomic characterization and cellular fluorescence tracing with chemical analogues of synaptamide reveal specific binding of GPR110 to synaptamide, which triggers cAMP production with low nM potency. Disruption of this binding or GPR110 gene knockout abolishes while GPR110 overexpression enhances synaptamide-induced bioactivity. GPR110 is highly expressed in fetal brains but rapidly decreases after birth. GPR110 knockout mice show significant deficits in object recognition and spatial memory. GPR110 deorphanized as a functional synaptamide receptor provides a novel target for neurodevelopmental control and new insight into mechanisms by which DHA promotes brain development and function.
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32
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Vetrini F, D'Alessandro LCA, Akdemir ZC, Braxton A, Azamian MS, Eldomery MK, Miller K, Kois C, Sack V, Shur N, Rijhsinghani A, Chandarana J, Ding Y, Holtzman J, Jhangiani SN, Muzny DM, Gibbs RA, Eng CM, Hanchard NA, Harel T, Rosenfeld JA, Belmont JW, Lupski JR, Yang Y. Bi-allelic Mutations in PKD1L1 Are Associated with Laterality Defects in Humans. Am J Hum Genet 2016; 99:886-893. [PMID: 27616478 DOI: 10.1016/j.ajhg.2016.07.011] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2016] [Accepted: 07/11/2016] [Indexed: 01/23/2023] Open
Abstract
Disruption of the establishment of left-right (L-R) asymmetry leads to situs anomalies ranging from situs inversus totalis (SIT) to situs ambiguus (heterotaxy). The genetic causes of laterality defects in humans are highly heterogeneous. Via whole-exome sequencing (WES), we identified homozygous mutations in PKD1L1 from three affected individuals in two unrelated families. PKD1L1 encodes a polycystin-1-like protein and its loss of function is known to cause laterality defects in mouse and medaka fish models. Family 1 had one fetus and one deceased child with heterotaxy and complex congenital heart malformations. WES identified a homozygous splicing mutation, c.6473+2_6473+3delTG, which disrupts the invariant splice donor site in intron 42, in both affected individuals. In the second family, a homozygous c.5072G>C (p.Cys1691Ser) missense mutation was detected in an individual with SIT and congenital heart disease. The p.Cys1691Ser substitution affects a highly conserved cysteine residue and is predicted by molecular modeling to disrupt a disulfide bridge essential for the proper folding of the G protein-coupled receptor proteolytic site (GPS) motif. Damaging effects associated with substitutions of this conserved cysteine residue in the GPS motif have also been reported in other genes, namely GPR56, BAI3, and PKD1 in human and lat-1 in C. elegans, further supporting the likely pathogenicity of p.Cys1691Ser in PKD1L1. The identification of bi-allelic PKD1L1 mutations recapitulates previous findings regarding phenotypic consequences of loss of function of the orthologous genes in mice and medaka fish and further expands our understanding of genetic contributions to laterality defects in humans.
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Affiliation(s)
| | - Lisa C A D'Alessandro
- Division of Cardiology, Texas Children's Hospital, Houston, TX 77030, USA; Department of Pediatrics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Zeynep C Akdemir
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Alicia Braxton
- Baylor Genetics, Houston, TX 77030, USA; Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Mahshid S Azamian
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Mohammad K Eldomery
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | | | | | | | | | | | | | - Yan Ding
- Human Genome Sequencing Center, Baylor College of Medicine, Houston, TX 77030, USA
| | - Judy Holtzman
- Genetics Department, Kaiser Permanente Medical Group, San Jose, CA 95123, USA
| | - Shalini N Jhangiani
- Human Genome Sequencing Center, Baylor College of Medicine, Houston, TX 77030, USA
| | - Donna M Muzny
- Human Genome Sequencing Center, Baylor College of Medicine, Houston, TX 77030, USA
| | - Richard A Gibbs
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA; Human Genome Sequencing Center, Baylor College of Medicine, Houston, TX 77030, USA
| | - Christine M Eng
- Baylor Genetics, Houston, TX 77030, USA; Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Neil A Hanchard
- Department of Pediatrics, Baylor College of Medicine, Houston, TX 77030, USA; Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Tamar Harel
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Jill A Rosenfeld
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - John W Belmont
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - James R Lupski
- Department of Pediatrics, Baylor College of Medicine, Houston, TX 77030, USA; Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA; Human Genome Sequencing Center, Baylor College of Medicine, Houston, TX 77030, USA
| | - Yaping Yang
- Baylor Genetics, Houston, TX 77030, USA; Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA.
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Chang GW, Hsiao CC, Peng YM, Vieira Braga F, Kragten N, Remmerswaal E, van de Garde M, Straussberg R, König G, Kostenis E, Knäuper V, Meyaard L, van Lier R, van Gisbergen K, Lin HH, Hamann J. The Adhesion G Protein-Coupled Receptor GPR56/ADGRG1 Is an Inhibitory Receptor on Human NK Cells. Cell Rep 2016; 15:1757-70. [DOI: 10.1016/j.celrep.2016.04.053] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2015] [Revised: 01/22/2016] [Accepted: 04/13/2016] [Indexed: 10/21/2022] Open
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Chiang NY, Chang GW, Huang YS, Peng YM, Hsiao CC, Kuo ML, Lin HH. Heparin interacts with the adhesion GPCR GPR56, reduces receptor shedding, and promotes cell adhesion and motility. J Cell Sci 2016; 129:2156-69. [PMID: 27068534 DOI: 10.1242/jcs.174458] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2015] [Accepted: 03/31/2016] [Indexed: 12/11/2022] Open
Abstract
GPR56 is an adhesion-class G-protein-coupled receptor responsible for bilateral frontoparietal polymicrogyria (BFPP), a severe disorder of cortical formation. Additionally, GPR56 is involved in biological processes as diverse as hematopoietic stem cell generation and maintenance, myoblast fusion, muscle hypertrophy, immunoregulation and tumorigenesis. Collagen III and tissue transglutaminase 2 (TG2) have been revealed as the matricellular ligands of GPR56 involved in BFPP and melanoma development, respectively. In this study, we identify heparin as a glycosaminoglycan interacting partner of GPR56. Analyses of truncated and mutant GPR56 proteins reveal two basic-residue-rich clusters, R(26)GHREDFRFC(35) and L(190)KHPQKASRRP(200), as the major heparin-interacting motifs that overlap partially with the collagen III- and TG2-binding sites. Interestingly, the GPR56-heparin interaction is modulated by collagen III but not TG2, even though both ligands are also heparin-binding proteins. Finally, we show that the interaction with heparin reduces GPR56 receptor shedding, and enhances cell adhesion and motility. These results provide novel insights into the interaction of GPR56 with its multiple endogenous ligands and have functional implications in diseases such as BFPP and cancer.
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Affiliation(s)
- Nien-Yi Chiang
- Department of Microbiology and Immunology, Chang Gung University, Tao-Yuan 333, Taiwan
| | - Gin-Wen Chang
- Department of Microbiology and Immunology, Chang Gung University, Tao-Yuan 333, Taiwan
| | - Yi-Shu Huang
- Department of Microbiology and Immunology, Chang Gung University, Tao-Yuan 333, Taiwan
| | - Yen-Ming Peng
- Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Tao-Yuan 333, Taiwan
| | - Cheng-Chih Hsiao
- Department of Microbiology and Immunology, Chang Gung University, Tao-Yuan 333, Taiwan
| | - Ming-Ling Kuo
- Department of Microbiology and Immunology, Chang Gung University, Tao-Yuan 333, Taiwan Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Tao-Yuan 333, Taiwan Chang Gung Immunology Consortium, Chang Gung Memorial Hospital and Chang Gung University, Tao-Yuan 333, Taiwan Division of Allergy, Asthma, and Rheumatology, Department of Pediatrics, Chang Gung Memorial Hospital-Linkou, Tao-Yuan 333, Taiwan
| | - Hsi-Hsien Lin
- Department of Microbiology and Immunology, Chang Gung University, Tao-Yuan 333, Taiwan Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Tao-Yuan 333, Taiwan Chang Gung Immunology Consortium, Chang Gung Memorial Hospital and Chang Gung University, Tao-Yuan 333, Taiwan Department of Anatomic Pathology, Chang Gung Memorial Hospital-Linkou, Tao-Yuan 333, Taiwan
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Kishore A, Purcell RH, Nassiri-Toosi Z, Hall RA. Stalk-dependent and Stalk-independent Signaling by the Adhesion G Protein-coupled Receptors GPR56 (ADGRG1) and BAI1 (ADGRB1). J Biol Chem 2016; 291:3385-94. [PMID: 26710850 PMCID: PMC4751382 DOI: 10.1074/jbc.m115.689349] [Citation(s) in RCA: 84] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2015] [Revised: 12/23/2015] [Indexed: 11/06/2022] Open
Abstract
The adhesion G protein-coupled receptors (aGPCRs) are a large yet poorly understood family of seven-transmembrane proteins. A defining characteristic of the aGPCR family is the conserved GAIN domain, which has autoproteolytic activity and can cleave the receptors near the first transmembrane domain. Several aGPCRs, including ADGRB1 (BAI1 or B1) and ADGRG1 (GPR56 or G1), have been found to exhibit significantly increased constitutive activity when truncated to mimic GAIN domain cleavage (ΔNT). Recent reports have suggested that the new N-terminal stalk, which is revealed by GAIN domain cleavage, can directly activate aGPCRs as a tethered agonist. We tested this hypothesis in studies on two distinct aGPCRs, B1 and G1, by engineering mutant receptors lacking the entire NT including the stalk (B1- and G1-SL, with "SL" indicating "stalkless"). These receptors were evaluated in a battery of signaling assays and compared with full-length wild-type and cleavage-mimicking (ΔNT) forms of the two receptors. We found that B1-SL, in multiple assays, exhibited robust signaling activity, suggesting that the membrane-proximal stalk region is not necessary for its activation. For G1, however, the results were mixed, with the SL mutant exhibiting robust activity in several signaling assays (including TGFα shedding, activation of NFAT luciferase, and β-arrestin recruitment) but reduced activity relative to ΔNT in a distinct assay (activation of SRF luciferase). These data support a model in which the activation of certain pathways downstream of aGPCRs is stalk-dependent, whereas signaling to other pathways is stalk-independent.
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Affiliation(s)
- Ayush Kishore
- From the Department of Pharmacology, Emory University School of Medicine, Atlanta, Georgia 30322
| | - Ryan H Purcell
- From the Department of Pharmacology, Emory University School of Medicine, Atlanta, Georgia 30322
| | - Zahra Nassiri-Toosi
- From the Department of Pharmacology, Emory University School of Medicine, Atlanta, Georgia 30322
| | - Randy A Hall
- From the Department of Pharmacology, Emory University School of Medicine, Atlanta, Georgia 30322
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Abstract
The adhesion G protein-coupled receptors (aGPCRs) are a family of 33 receptors in humans that are widely expressed in various tissues and involved in many diverse biological processes. These receptors possess extremely large N-termini (NT) containing a variety of adhesion domains. A distinguishing feature of these receptors is the presence within the NT of a highly conserved GPCR autoproteolysis-inducing (GAIN) domain, which mediates autoproteolysis of the receptors into N-terminal and C-terminal fragments that stay non-covalently associated. The downstream signaling pathways and G protein-coupling preferences of many aGPCRs have recently been elucidated, and putative endogenous ligands for some aGPCRs have also been discovered and characterized in recent years. A pivotal observation for aGPCRs has been that deletion or removal of the NT up the point of GAIN cleavage results in constitutive receptor activation. For at least some aGPCRs, this activation is dependent on the unmasking of specific agonistic peptide sequences within the N-terminal stalk region (i.e., the region between the site of GAIN domain cleavage and the first transmembrane domain). However, the specific peptide sequences involved and the overall importance of the stalk region for activation can vary greatly from receptor to receptor. An emerging theme of work in this area is that aGPCRs are capable of versatile signaling activity that may be fine-tuned to suit the specific physiological roles played by the various members of this family.
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Affiliation(s)
- Ayush Kishore
- Department of Pharmacology, Emory University School of Medicine, 1510 Clifton Road NE, Atlanta, GA, 30322, USA
| | - Randy A Hall
- Department of Pharmacology, Emory University School of Medicine, 1510 Clifton Road NE, Atlanta, GA, 30322, USA.
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Adhesion GPCRs as Novel Actors in Neural and Glial Cell Functions: From Synaptogenesis to Myelination. Handb Exp Pharmacol 2016; 234:275-298. [PMID: 27832492 DOI: 10.1007/978-3-319-41523-9_12] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Adhesion G-protein-coupled receptors (aGPCRs) are emerging as key regulators of nervous system development and health. aGPCRs can regulate many aspects of neural development, including cell signaling, cell-cell and cell-matrix interactions, and, potentially, mechanosensation. Here, we specifically focus on the roles of several aGPCRs in synapse biology, dendritogenesis, and myelinating glial cell development. The lessons learned from these examples may be extrapolated to other contexts in the nervous system and beyond.
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Yang TY, Chiang NY, Tseng WY, Pan HL, Peng YM, Shen JJ, Wu KA, Kuo ML, Chang GW, Lin HH. Expression and immunoaffinity purification of recombinant soluble human GPR56 protein for the analysis of GPR56 receptor shedding by ELISA. Protein Expr Purif 2015; 109:85-92. [DOI: 10.1016/j.pep.2014.11.013] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2014] [Revised: 11/17/2014] [Accepted: 11/19/2014] [Indexed: 12/22/2022]
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Adhesion G protein-coupled receptors are activated by exposure of a cryptic tethered agonist. Proc Natl Acad Sci U S A 2015; 112:6194-9. [PMID: 25918380 DOI: 10.1073/pnas.1421785112] [Citation(s) in RCA: 188] [Impact Index Per Article: 20.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The large class of adhesion G protein-coupled receptors (aGPCRs) bind extracellular matrix or neighboring cell-surface ligands to regulate organ and tissue development through an unknown activation mechanism. We examined aGPCR activation using two prototypical aGPCRs, GPR56 and GPR110. Active dissociation of the noncovalently bound GPR56 or GPR110 extracellular domains (ECDs) from the respective seven-transmembrane (7TM) domains relieved an inhibitory influence and permitted both receptors to activate defined G protein subtypes. After ECD displacement, the newly revealed short N-terminal stalk regions of the 7TM domains were found to be essential for G protein activation. Synthetic peptides comprising these stalks potently activated GPR56 or GPR110 in vitro or in cells, demonstrating that the stalks comprise a tethered agonist that was encrypted within the ECD. Establishment of an aGPCR activation mechanism provides a rational platform for the development of aGPCR synthetic modulators that could find clinical utility toward aGPCR-directed disease.
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Giera S, Deng Y, Luo R, Ackerman SD, Mogha A, Monk KR, Ying Y, Jeong SJ, Makinodan M, Bialas AR, Chang BS, Stevens B, Corfas G, Piao X. The adhesion G protein-coupled receptor GPR56 is a cell-autonomous regulator of oligodendrocyte development. Nat Commun 2015; 6:6121. [PMID: 25607655 PMCID: PMC4302951 DOI: 10.1038/ncomms7121] [Citation(s) in RCA: 102] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2014] [Accepted: 12/14/2014] [Indexed: 01/17/2023] Open
Abstract
Mutations in GPR56, a member of the adhesion G protein-coupled receptor family, cause a human brain malformation called bilateral frontoparietal polymicrogyria (BFPP). Magnetic resonance imaging (MRI) of BFPP brains reveals myelination defects in addition to brain malformation. However, the cellular role of GPR56 in oligodendrocyte development remains unknown. Here, we demonstrate that loss of Gpr56 leads to hypomyelination of the central nervous system in mice. GPR56 levels are abundant throughout early stages of oligodendrocyte development, but are downregulated in myelinating oligodendrocytes. Gpr56-knockout mice manifest with decreased oligodendrocyte precursor cell (OPC) proliferation and diminished levels of active RhoA, leading to fewer mature oligodendrocytes and a reduced number of myelinated axons in the corpus callosum and optic nerves. Conditional ablation of Gpr56 in OPCs leads to a reduced number of mature oligodendrocytes as seen in constitutive knockout of Gpr56. Together, our data define GPR56 as a cell-autonomous regulator of oligodendrocyte development.
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Affiliation(s)
- Stefanie Giera
- Division of Newborn Medicine, Department of Medicine, Boston Children's Hospital and Harvard Medical School, Boston, Massachusetts 02115, USA
| | - Yiyu Deng
- Division of Newborn Medicine, Department of Medicine, Boston Children's Hospital and Harvard Medical School, Boston, Massachusetts 02115, USA
| | - Rong Luo
- Division of Newborn Medicine, Department of Medicine, Boston Children's Hospital and Harvard Medical School, Boston, Massachusetts 02115, USA
| | - Sarah D Ackerman
- Department of Developmental Biology, Washington University School of Medicine, St Louis, Missouri 63110, USA
| | - Amit Mogha
- Department of Developmental Biology, Washington University School of Medicine, St Louis, Missouri 63110, USA
| | - Kelly R Monk
- 1] Department of Developmental Biology, Washington University School of Medicine, St Louis, Missouri 63110, USA [2] Hope Center for Neurological Disorders, Washington University School of Medicine, St Louis, Missouri 63110, USA
| | - Yanqin Ying
- Division of Newborn Medicine, Department of Medicine, Boston Children's Hospital and Harvard Medical School, Boston, Massachusetts 02115, USA
| | - Sung-Jin Jeong
- Division of Newborn Medicine, Department of Medicine, Boston Children's Hospital and Harvard Medical School, Boston, Massachusetts 02115, USA
| | - Manabu Makinodan
- 1] F.M. Kirby Neurobiology Center, Children's Hospital, Harvard Medical School, Boston, Massachusetts 02115, USA [2] Department of Neurology, Harvard Medical School, Boston, Massachusetts 02115, USA
| | - Allison R Bialas
- 1] F.M. Kirby Neurobiology Center, Children's Hospital, Harvard Medical School, Boston, Massachusetts 02115, USA [2] Department of Neurology, Harvard Medical School, Boston, Massachusetts 02115, USA
| | - Bernard S Chang
- Comprehensive Epilepsy Center, Department of Neurology, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts 02115, USA
| | - Beth Stevens
- 1] F.M. Kirby Neurobiology Center, Children's Hospital, Harvard Medical School, Boston, Massachusetts 02115, USA [2] Department of Neurology, Harvard Medical School, Boston, Massachusetts 02115, USA
| | - Gabriel Corfas
- 1] F.M. Kirby Neurobiology Center, Children's Hospital, Harvard Medical School, Boston, Massachusetts 02115, USA [2] Department of Neurology, Harvard Medical School, Boston, Massachusetts 02115, USA
| | - Xianhua Piao
- Division of Newborn Medicine, Department of Medicine, Boston Children's Hospital and Harvard Medical School, Boston, Massachusetts 02115, USA
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41
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Wang XJ, Zhang DL, Xu ZG, Ma ML, Wang WB, Li LL, Han XL, Huo Y, Yu X, Sun JP. Understanding cadherin EGF LAG seven-pass G-type receptors. J Neurochem 2014; 131:699-711. [PMID: 25280249 DOI: 10.1111/jnc.12955] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2014] [Revised: 09/05/2014] [Accepted: 09/22/2014] [Indexed: 12/21/2022]
Abstract
The cadherin epidermal growth factor (EGF) laminin G (LAG) seven-pass G-type receptors (CELSRs) are a special subgroup of adhesion G protein-coupled receptors, which are pivotal regulators of many biologic processes such as neuronal/endocrine cell differentiation, vessel valve formation, and the control of planar cell polarity during embryonic development. All three members of the CELSR family (CELSR1-3) have large ecto-domains that form homophilic interactions and encompass more than 2000 amino acids. Mutations in the ecto-domain or other gene locations of CELSRs are associated with neural tube defects and other diseases in humans. Celsr knockout (KO) animals have many developmental defects. Therefore, specific agonists or antagonists of CELSR members may have therapeutic potential. Although significant progress has been made regarding the functions and biochemical properties of CELSRs, our knowledge of these receptors is still lacking, especially considering that they are broadly distributed but have few characterized functions in a limited number of tissues. The dynamic activation and inactivation of CELSRs and the presence of endogenous ligands beyond homophilic interactions remain elusive, as do the regulatory mechanisms and downstream signaling of these receptors. Given this motivation, future studies with more advanced cell biology or biochemical tools, such as conditional KO mice, may provide further insights into the mechanisms underlying CELSR function, laying the foundation for the design of new CELSR-targeted therapeutic reagents. The cadherin EGF LAG seven-pass G-type receptors (CELSRs) are a special subgroup of adhesion G protein-coupled receptors (GPCRs), which have large ecto-domains that form homophilic interactions and encompass more than 2000 amino acids. Recent studies have revealed that CELSRs are pivotal regulators of many biological processes, such as neuronal/endocrine cell differentiation, vessel valve formation and the control of planar cell polarity during embryonic development.
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Affiliation(s)
- Xiao-Jing Wang
- Key Laboratory Experimental Teratology of the Ministry of Education and Department of Biochemistry and Molecular Biology, Shandong University School of Medicine, Jinan, Shandong, China; Department of Cell Biology, Shandong University School of Medicine, Jinan, Shandong, China; Shandong Provincial School Key laboratory for Protein Science of Chronic Degenerative Diseases, Jinan, Shandong, China
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42
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Tao YX, Conn PM. Chaperoning G protein-coupled receptors: from cell biology to therapeutics. Endocr Rev 2014; 35:602-47. [PMID: 24661201 PMCID: PMC4105357 DOI: 10.1210/er.2013-1121] [Citation(s) in RCA: 96] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/21/2013] [Accepted: 03/14/2014] [Indexed: 12/13/2022]
Abstract
G protein-coupled receptors (GPCRs) are membrane proteins that traverse the plasma membrane seven times (hence, are also called 7TM receptors). The polytopic structure of GPCRs makes the folding of GPCRs difficult and complex. Indeed, many wild-type GPCRs are not folded optimally, and defects in folding are the most common cause of genetic diseases due to GPCR mutations. Both general and receptor-specific molecular chaperones aid the folding of GPCRs. Chemical chaperones have been shown to be able to correct the misfolding in mutant GPCRs, proving to be important tools for studying the structure-function relationship of GPCRs. However, their potential therapeutic value is very limited. Pharmacological chaperones (pharmacoperones) are potentially important novel therapeutics for treating genetic diseases caused by mutations in GPCR genes that resulted in misfolded mutant proteins. Pharmacoperones also increase cell surface expression of wild-type GPCRs; therefore, they could be used to treat diseases that do not harbor mutations in GPCRs. Recent studies have shown that indeed pharmacoperones work in both experimental animals and patients. High-throughput assays have been developed to identify new pharmacoperones that could be used as therapeutics for a number of endocrine and other genetic diseases.
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Affiliation(s)
- Ya-Xiong Tao
- Department of Anatomy, Physiology, and Pharmacology (Y.-X.T.), College of Veterinary Medicine, Auburn University, Auburn, Alabama 36849-5519; and Departments of Internal Medicine and Cell Biology (P.M.C.), Texas Tech University Health Science Center, Lubbock, Texas 79430-6252
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Fallet-Bianco C, Laquerrière A, Poirier K, Razavi F, Guimiot F, Dias P, Loeuillet L, Lascelles K, Beldjord C, Carion N, Toussaint A, Revencu N, Addor MC, Lhermitte B, Gonzales M, Martinovich J, Bessieres B, Marcy-Bonnière M, Jossic F, Marcorelles P, Loget P, Chelly J, Bahi-Buisson N. Mutations in tubulin genes are frequent causes of various foetal malformations of cortical development including microlissencephaly. Acta Neuropathol Commun 2014; 2:69. [PMID: 25059107 PMCID: PMC4222268 DOI: 10.1186/2051-5960-2-69] [Citation(s) in RCA: 84] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2014] [Accepted: 06/04/2014] [Indexed: 01/18/2023] Open
Abstract
Complex cortical malformations associated with mutations in tubulin genes are commonly referred to as “Tubulinopathies”. To further characterize the mutation frequency and phenotypes associated with tubulin mutations, we studied a cohort of 60 foetal cases. Twenty-six tubulin mutations were identified, of which TUBA1A mutations were the most prevalent (19 cases), followed by TUBB2B (6 cases) and TUBB3 (one case). Three subtypes clearly emerged. The most frequent (n = 13) was microlissencephaly with corpus callosum agenesis, severely hypoplastic brainstem and cerebellum. The cortical plate was either absent (6/13), with a 2–3 layered pattern (5/13) or less frequently thickened (2/13), often associated with neuroglial overmigration (4/13). All cases had voluminous germinal zones and ganglionic eminences. The second subtype was lissencephaly (n = 7), either classical (4/7) or associated with cerebellar hypoplasia (3/7) with corpus callosum agenesis (6/7). All foetuses with lissencephaly and cerebellar hypoplasia carried distinct TUBA1A mutations, while those with classical lissencephaly harbored recurrent mutations in TUBA1A (3 cases) or TUBB2B (1 case). The third group was polymicrogyria-like cortical dysplasia (n = 6), consisting of asymmetric multifocal or generalized polymicrogyria with inconstant corpus callosum agenesis (4/6) and hypoplastic brainstem and cerebellum (3/6). Polymicrogyria was either unlayered or 4-layered with neuronal heterotopias (5/6) and occasional focal neuroglial overmigration (2/6). Three had TUBA1A mutations and 3 TUBB2B mutations. Foetal TUBA1A tubulinopathies most often consist in microlissencephaly or classical lissencephaly with corpus callosum agenesis, but polymicrogyria may also occur. Conversely, TUBB2B mutations are responsible for either polymicrogyria (4/6) or microlissencephaly (2/6).
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44
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Novel functional complexity of polycystin-1 by GPS cleavage in vivo: role in polycystic kidney disease. Mol Cell Biol 2014; 34:3341-53. [PMID: 24958103 DOI: 10.1128/mcb.00687-14] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Polycystin-1 (Pc1) cleavage at the G protein-coupled receptor (GPCR) proteolytic site (GPS) is required for normal kidney morphology in humans and mice. We found a complex pattern of endogenous Pc1 forms by GPS cleavage. GPS cleavage generates not only the heterodimeric cleaved full-length Pc1 (Pc1(cFL)) in which the N-terminal fragment (NTF) remains noncovalently associated with the C-terminal fragment (CTF) but also a novel (Pc1) form (Pc1(deN)) in which NTF becomes detached from CTF. Uncleaved Pc1 (Pc1(U)) resides primarily in the endoplasmic reticulum (ER), whereas both Pc1(cFL) and Pc1(deN) traffic through the secretory pathway in vivo. GPS cleavage is not a prerequisite, however, for Pc1 trafficking in vivo. Importantly, Pc1(deN) is predominantly found at the plasma membrane of renal epithelial cells. By functional genetic complementation with five Pkd1 mouse models, we discovered that CTF plays a crucial role in Pc1(deN) trafficking. Our studies support GPS cleavage as a critical regulatory mechanism of Pc1 biogenesis and trafficking for proper kidney development and homeostasis.
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45
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Luo R, Jeong SJ, Yang A, Wen M, Saslowsky DE, Lencer WI, Araç D, Piao X. Mechanism for adhesion G protein-coupled receptor GPR56-mediated RhoA activation induced by collagen III stimulation. PLoS One 2014; 9:e100043. [PMID: 24949629 PMCID: PMC4065004 DOI: 10.1371/journal.pone.0100043] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2014] [Accepted: 05/20/2014] [Indexed: 12/12/2022] Open
Abstract
GPR56 is a member of the adhesion G protein-coupled receptor (GPCR) family. Despite the importance of GPR56 in brain development, where mutations cause a devastating human brain malformation called bilateral frontoparietal polymicrogyria (BFPP), the signaling mechanism(s) remain largely unknown. Like many other adhesion GPCRs, GPR56 is cleaved via a GPCR autoproteolysis-inducing (GAIN) domain into N- and C-terminal fragments (GPR56N and GPR56C); however, the biological significance of this cleavage is elusive. Taking advantage of the recent identification of a GPR56 ligand and the presence of BFPP-associated mutations, we investigated the molecular mechanism of GPR56 signaling. We demonstrate that ligand binding releases GPR56N from the membrane-bound GPR56C and triggers the association of GPR56C with lipid rafts and RhoA activation. Furthermore, one of the BFPP-associated mutations, L640R, does not affect collagen III-induced lipid raft association of GPR56. Instead, it specifically abolishes collagen III-mediated RhoA activation. Together, these findings reveal a novel signaling mechanism that may apply to other members of the adhesion GPCR family.
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Affiliation(s)
- Rong Luo
- Division of Newborn Medicine, Boston Children’s Hospital and Harvard Medical School, Boston, Massachusetts, United States of America
| | - Sung-Jin Jeong
- Division of Newborn Medicine, Boston Children’s Hospital and Harvard Medical School, Boston, Massachusetts, United States of America
| | - Annie Yang
- Division of Newborn Medicine, Boston Children’s Hospital and Harvard Medical School, Boston, Massachusetts, United States of America
| | - Miaoyun Wen
- Division of Newborn Medicine, Boston Children’s Hospital and Harvard Medical School, Boston, Massachusetts, United States of America
| | - David E. Saslowsky
- Division of Gastroenterology, Boston Children's Hospital, Boston, Massachusetts, United States of America
| | - Wayne I. Lencer
- Division of Gastroenterology, Boston Children's Hospital, Boston, Massachusetts, United States of America
| | - Demet Araç
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, Illinois, United States of America
| | - Xianhua Piao
- Division of Newborn Medicine, Boston Children’s Hospital and Harvard Medical School, Boston, Massachusetts, United States of America
- * E-mail: .
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46
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Fujii Y, Ishikawa N, Kobayashi Y, Kobayashi M, Kato M. Compound heterozygosity in GPR56 with bilateral frontoparietal polymicrogyria. Brain Dev 2014; 36:528-31. [PMID: 23981349 DOI: 10.1016/j.braindev.2013.07.015] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/24/2013] [Revised: 07/28/2013] [Accepted: 07/31/2013] [Indexed: 12/17/2022]
Abstract
Polymicrogyria is caused by a diverse etiology, one of which is gene mutation. At present, only one gene (GPR56) is known to cause polymicrogyria, which leads to a distinctive phenotype termed bilateral frontoparietal polymicrogyria (BFPP). BFPP is an autosomal recessive inherited human brain malformation with abnormal cortical lamination. Here, we identified compound heterozygous GPR56 mutations in a patient with BFPP. The proband was a Japanese female born from non-consanguineous parents. She presented with mental retardation, developmental motor delay, epilepsy exhibiting the feature of Lennox-Gastaut syndrome, exotropia, bilateral polymicrogyria with a relatively spared perisylvian region, bilateral patchy-white-matter MRI signal changes, and hypoplastic pontine basis. GPR56 sequence analysis revealed a c.107G>A substitution leading to a p.S36N, and a c.113G>A leading to a p.R38Q. Although affected individuals with compound heterozygosity in GPR56 have not been previously described, we presume that compound heterozygosity of these two mutations in a ligand binding domain within the extracellular N-terminus of protein could result in BFPP. In addition, we observed unusually less involvement of perisylvian cortex for polymicrogyria, and Lennox-Gastaut syndrome for epilepsy, which are likely common features in patients with BFPP caused by GPR56 mutations.
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Affiliation(s)
- Yuji Fujii
- Department of Pediatrics, Hiroshima University Hospital, Hiroshima, Japan.
| | - Nobutsune Ishikawa
- Department of Pediatrics, Hiroshima University Hospital, Hiroshima, Japan
| | | | - Masao Kobayashi
- Department of Pediatrics, Hiroshima University Hospital, Hiroshima, Japan
| | - Mitsuhiro Kato
- Department of Pediatrics, Yamagata University, Faculty of Medicine, Yamagata, Japan
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47
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Stephenson JR, Purcell RH, Hall RA. The BAI subfamily of adhesion GPCRs: synaptic regulation and beyond. Trends Pharmacol Sci 2014; 35:208-15. [PMID: 24642458 DOI: 10.1016/j.tips.2014.02.002] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2013] [Revised: 01/30/2014] [Accepted: 02/02/2014] [Indexed: 01/19/2023]
Abstract
The brain-specific angiogenesis inhibitors 1-3 (BAI1-3) comprise a subfamily of adhesion G-protein-coupled receptors (GPCRs). These receptors are highly expressed in the brain and were first studied for their ability to inhibit angiogenesis and tumor formation. Subsequently, BAI1 was found to play roles in apoptotic cell phagocytosis and myoblast fusion. Until recently, however, little was known about the physiological importance of the BAI subfamily in the context of normal brain function. Recent work has provided evidence for key roles of BAI1-3 in the regulation of synaptogenesis and dendritic spine formation. In this review, we summarize the current understanding of the BAI subfamily with regard to downstream signaling pathways, physiological actions, and potential importance as novel drug targets in the treatment of psychiatric and neurological diseases.
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Affiliation(s)
- Jason R Stephenson
- Department of Pharmacology, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Ryan H Purcell
- Department of Pharmacology, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Randy A Hall
- Department of Pharmacology, Emory University School of Medicine, Atlanta, GA 30322, USA.
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48
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Liebscher I, Schöneberg T, Prömel S. Progress in demystification of adhesion G protein-coupled receptors. Biol Chem 2014; 394:937-50. [PMID: 23518449 DOI: 10.1515/hsz-2013-0109] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2013] [Accepted: 03/19/2013] [Indexed: 02/03/2023]
Abstract
Adhesion G protein-coupled receptors (aGPCR) form the second largest class of GPCR. They are phylogenetically old and have been highly conserved during evolution. Mutations in representatives of this class are associated with severe diseases such as Usher Syndrome, a combined congenital deaf-blindness, or bifrontal parietal polymicrogyria. The main characteristics of aGPCR are their enormous size and the complexity of their N termini. They contain a highly conserved GPCR proteolytic site (GPS) and several functional domains that have been implicated in cell-cell and cell-matrix interactions. Adhesion GPCR have been proposed to serve a dual function as adhesion molecules and as classical receptors. However, until recently there was no proof that aGPCR indeed couple to G proteins or even function as classical receptors. In this review, we have summarized and discussed recent evidence that aGPCR present many functional features of classical GPCR, including multiple G protein-coupling abilities, G protein-independent signaling and oligomerization, but also specific signaling properties only found in aGPCR.
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Affiliation(s)
- Ines Liebscher
- Molecular Biochemistry, Institute of Biochemistry, Medical Faculty, University of Leipzig, Johannisallee 30, D-04103 Leipzig, Germany
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49
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Wu MP, Doyle JR, Barry B, Beauvais A, Rozkalne A, Piao X, Lawlor MW, Kopin AS, Walsh CA, Gussoni E. G-protein coupled receptor 56 promotes myoblast fusion through serum response factor- and nuclear factor of activated T-cell-mediated signalling but is not essential for muscle development in vivo. FEBS J 2013; 280:6097-113. [PMID: 24102982 PMCID: PMC3877849 DOI: 10.1111/febs.12529] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2013] [Revised: 08/24/2013] [Accepted: 09/04/2013] [Indexed: 12/28/2022]
Abstract
Mammalian muscle cell differentiation is a complex process of multiple steps for which many of the factors involved have not yet been defined. In a screen to identify the regulators of myogenic cell fusion, we found that the gene for G-protein coupled receptor 56 (GPR56) was transiently up-regulated during the early fusion of human myoblasts. Human mutations in the gene for GPR56 cause the disease bilateral frontoparietal polymicrogyria; however, the consequences of receptor dysfunction on muscle development have not been explored. Using knockout mice, we defined the role of GPR56 in skeletal muscle. GPR56(-/-) myoblasts have decreased fusion and smaller myotube sizes in culture. In addition, a loss of GPR56 expression in muscle cells results in decreases or delays in the expression of myogenic differentiation 1, myogenin and nuclear factor of activated T-cell (NFAT)c2. Our data suggest that these abnormalities result from decreased GPR56-mediated serum response element and NFAT signalling. Despite these changes, no overt differences in phenotype were identified in the muscle of GPR56 knockout mice, which presented only a mild but statistically significant elevation of serum creatine kinase compared to wild-type. In agreement with these findings, clinical data from 13 bilateral frontoparietal polymicrogyria patients revealed mild serum creatine kinase increase in only two patients. In summary, targeted disruption of GPR56 in mice results in myoblast abnormalities. The absence of a severe muscle phenotype in GPR56 knockout mice and human patients suggests that other factors may compensate for the lack of this G-protein coupled receptor during muscle development and that the motor delay observed in these patients is likely not a result of primary muscle abnormalities.
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Affiliation(s)
- Melissa P. Wu
- Biological and Biomedical Sciences, Harvard Medical School, Boston MA 02115, USA
- Division of Genetics, Boston Children’s Hospital, Boston MA 02115, USA
| | - Jamie R. Doyle
- Molecular Cardiology Research Institute, Tufts Medical Center, Boston, MA 02111, USA
| | - Brenda Barry
- Division of Genetics, Boston Children’s Hospital, Boston MA 02115, USA
- Howard Hughes Medical Institute, Boston Children’s Hospital, Boston MA 02115, USA
| | - Ariane Beauvais
- Division of Genetics, Boston Children’s Hospital, Boston MA 02115, USA
| | - Anete Rozkalne
- Division of Genetics, Boston Children’s Hospital, Boston MA 02115, USA
| | - Xianhua Piao
- Division of Newborn Medicine, Boston Children’s Hospital, Boston MA 02115, USA
| | - Michael W. Lawlor
- Department of Pathology and Laboratory Medicine, Children’s Hospital of Wisconsin and Medical College of Wisconsin, Milwaukee WI 53226, USA
| | - Alan S. Kopin
- Molecular Cardiology Research Institute, Tufts Medical Center, Boston, MA 02111, USA
| | - Christopher A. Walsh
- Division of Genetics, Boston Children’s Hospital, Boston MA 02115, USA
- Howard Hughes Medical Institute, Boston Children’s Hospital, Boston MA 02115, USA
| | - Emanuela Gussoni
- Division of Genetics, Boston Children’s Hospital, Boston MA 02115, USA
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50
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Extrasynaptic muscarinic acetylcholine receptors on neuronal cell bodies regulate presynaptic function in Caenorhabditis elegans. J Neurosci 2013; 33:14146-59. [PMID: 23986249 DOI: 10.1523/jneurosci.1359-13.2013] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Acetylcholine (ACh) is a potent neuromodulator in the brain, and its effects on cognition and memory formation are largely performed through muscarinic acetylcholine receptors (mAChRs). mAChRs are often preferentially distributed on specialized membrane regions in neurons, but the significance of mAChR localization in modulating neuronal function is not known. Here we show that the Caenorhabditis elegans homolog of the M1/M3/M5 family of mAChRs, gar-3, is expressed in cholinergic motor neurons, and GAR-3-GFP fusion proteins localize to cell bodies where they are enriched at extrasynaptic regions that are in contact with the basal lamina. The GAR-3 N-terminal extracellular domain is necessary and sufficient for this asymmetric distribution, and mutation of a predicted N-linked glycosylation site within the N-terminus disrupts GAR-3-GFP localization. In transgenic animals expressing GAR-3 variants that are no longer asymmetrically localized, synaptic transmission at neuromuscular junctions is impaired and there is a reduction in the abundance of the presynaptic protein sphingosine kinase at release sites. Finally, GAR-3 can be activated by endogenously produced ACh released from neurons that do not directly contact cholinergic motor neurons. Together, our results suggest that humoral activation of asymmetrically localized mAChRs by ACh is an evolutionarily conserved mechanism by which ACh modulates neuronal function.
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