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Rees TA, Labastida-Ramírez A, Rubio-Beltrán E. Calcitonin/PAC 1 receptor splice variants: a blind spot in migraine research. Trends Pharmacol Sci 2023; 44:651-663. [PMID: 37543479 PMCID: PMC10529278 DOI: 10.1016/j.tips.2023.07.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Revised: 07/08/2023] [Accepted: 07/08/2023] [Indexed: 08/07/2023]
Abstract
The neuropeptides calcitonin gene-related peptide (CGRP) and pituitary adenylate cyclase-activating polypeptide (PACAP) and their receptors are linked to migraine neurobiology. Recent antimigraine therapeutics targeting the signaling of these neuropeptides are effective; however, some patients respond suboptimally, indicating an incomplete understanding of migraine pathophysiology. The CGRP- and PACAP-responsive receptors can be differentially spliced. It is known that receptor splice variants can have different pathophysiological effects in other receptor-mediated pain pathways. Despite considerable knowledge on the structural and pharmacological differences of the CGRP- and PACAP-responsive receptor splice variants and their expression in migraine-relevant tissues, their role in migraine is rarely considered. Here we shine a spotlight on the calcitonin and PACAP (PAC1) receptor splice variants and examine what implications they may have for drug activity and design.
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Affiliation(s)
- Tayla A Rees
- School of Biological Sciences, University of Auckland, Auckland, New Zealand; Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland, Auckland, New Zealand.
| | - Alejandro Labastida-Ramírez
- Headache Group, Wolfson Center for Age Related Diseases, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Eloisa Rubio-Beltrán
- Headache Group, Wolfson Center for Age Related Diseases, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
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Russo AF, Hay DL. CGRP physiology, pharmacology, and therapeutic targets: migraine and beyond. Physiol Rev 2023; 103:1565-1644. [PMID: 36454715 PMCID: PMC9988538 DOI: 10.1152/physrev.00059.2021] [Citation(s) in RCA: 54] [Impact Index Per Article: 54.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Revised: 11/23/2022] [Accepted: 11/27/2022] [Indexed: 12/03/2022] Open
Abstract
Calcitonin gene-related peptide (CGRP) is a neuropeptide with diverse physiological functions. Its two isoforms (α and β) are widely expressed throughout the body in sensory neurons as well as in other cell types, such as motor neurons and neuroendocrine cells. CGRP acts via at least two G protein-coupled receptors that form unusual complexes with receptor activity-modifying proteins. These are the CGRP receptor and the AMY1 receptor; in rodents, additional receptors come into play. Although CGRP is known to produce many effects, the precise molecular identity of the receptor(s) that mediates CGRP effects is seldom clear. Despite the many enigmas still in CGRP biology, therapeutics that target the CGRP axis to treat or prevent migraine are a bench-to-bedside success story. This review provides a contextual background on the regulation and sites of CGRP expression and CGRP receptor pharmacology. The physiological actions of CGRP in the nervous system are discussed, along with updates on CGRP actions in the cardiovascular, pulmonary, gastrointestinal, immune, hematopoietic, and reproductive systems and metabolic effects of CGRP in muscle and adipose tissues. We cover how CGRP in these systems is associated with disease states, most notably migraine. In this context, we discuss how CGRP actions in both the peripheral and central nervous systems provide a basis for therapeutic targeting of CGRP in migraine. Finally, we highlight potentially fertile ground for the development of additional therapeutics and combinatorial strategies that could be designed to modulate CGRP signaling for migraine and other diseases.
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Affiliation(s)
- Andrew F Russo
- Department of Molecular Physiology and Biophysics, University of Iowa, Iowa City, Iowa
- Department of Neurology, University of Iowa, Iowa City, Iowa
- Center for the Prevention and Treatment of Visual Loss, Department of Veterans Affairs Health Center, Iowa City, Iowa
| | - Debbie L Hay
- Department of Pharmacology and Toxicology, University of Otago, Dunedin, New Zealand
- Maurice Wilkins Centre for Molecular Biodiscovery, School of Biological Sciences, The University of Auckland, Auckland, New Zealand
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Kotliar IB, Lorenzen E, Schwenk JM, Hay DL, Sakmar TP. Elucidating the Interactome of G Protein-Coupled Receptors and Receptor Activity-Modifying Proteins. Pharmacol Rev 2023; 75:1-34. [PMID: 36757898 PMCID: PMC9832379 DOI: 10.1124/pharmrev.120.000180] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2020] [Accepted: 09/27/2022] [Indexed: 12/13/2022] Open
Abstract
G protein-coupled receptors (GPCRs) are known to interact with several other classes of integral membrane proteins that modulate their biology and pharmacology. However, the extent of these interactions and the mechanisms of their effects are not well understood. For example, one class of GPCR-interacting proteins, receptor activity-modifying proteins (RAMPs), comprise three related and ubiquitously expressed single-transmembrane span proteins. The RAMP family was discovered more than two decades ago, and since then GPCR-RAMP interactions and their functional consequences on receptor trafficking and ligand selectivity have been documented for several secretin (class B) GPCRs, most notably the calcitonin receptor-like receptor. Recent bioinformatics and multiplexed experimental studies suggest that GPCR-RAMP interactions might be much more widespread than previously anticipated. Recently, cryo-electron microscopy has provided high-resolution structures of GPCR-RAMP-ligand complexes, and drugs have been developed that target GPCR-RAMP complexes. In this review, we provide a summary of recent advances in techniques that allow the discovery of GPCR-RAMP interactions and their functional consequences and highlight prospects for future advances. We also provide an up-to-date list of reported GPCR-RAMP interactions based on a review of the current literature. SIGNIFICANCE STATEMENT: Receptor activity-modifying proteins (RAMPs) have emerged as modulators of many aspects of G protein-coupled receptor (GPCR)biology and pharmacology. The application of new methodologies to study membrane protein-protein interactions suggests that RAMPs interact with many more GPCRs than had been previously known. These findings, especially when combined with structural studies of membrane protein complexes, have significant implications for advancing GPCR-targeted drug discovery and the understanding of GPCR pharmacology, biology, and regulation.
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Affiliation(s)
- Ilana B Kotliar
- Laboratory of Chemical Biology and Signal Transduction, The Rockefeller University, New York, New York (I.B.K., E.L., T.P.S.); Tri-Institutional PhD Program in Chemical Biology, New York, New York (I.B.K.); Science for Life Laboratory, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH-Royal Institute of Technology, Solna, Sweden (J.M.S.); Department of Pharmacology and Toxicology, School of Biomedical Sciences, Division of Health Sciences, University of Otago, Dunedin, New Zealand (D.L.H.); and Department of Neurobiology, Care Sciences and Society (NVS), Division for Neurogeriatrics, Center for Alzheimer Research, Karolinska Institutet, Solna, Sweden (T.P.S.)
| | - Emily Lorenzen
- Laboratory of Chemical Biology and Signal Transduction, The Rockefeller University, New York, New York (I.B.K., E.L., T.P.S.); Tri-Institutional PhD Program in Chemical Biology, New York, New York (I.B.K.); Science for Life Laboratory, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH-Royal Institute of Technology, Solna, Sweden (J.M.S.); Department of Pharmacology and Toxicology, School of Biomedical Sciences, Division of Health Sciences, University of Otago, Dunedin, New Zealand (D.L.H.); and Department of Neurobiology, Care Sciences and Society (NVS), Division for Neurogeriatrics, Center for Alzheimer Research, Karolinska Institutet, Solna, Sweden (T.P.S.)
| | - Jochen M Schwenk
- Laboratory of Chemical Biology and Signal Transduction, The Rockefeller University, New York, New York (I.B.K., E.L., T.P.S.); Tri-Institutional PhD Program in Chemical Biology, New York, New York (I.B.K.); Science for Life Laboratory, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH-Royal Institute of Technology, Solna, Sweden (J.M.S.); Department of Pharmacology and Toxicology, School of Biomedical Sciences, Division of Health Sciences, University of Otago, Dunedin, New Zealand (D.L.H.); and Department of Neurobiology, Care Sciences and Society (NVS), Division for Neurogeriatrics, Center for Alzheimer Research, Karolinska Institutet, Solna, Sweden (T.P.S.)
| | - Debbie L Hay
- Laboratory of Chemical Biology and Signal Transduction, The Rockefeller University, New York, New York (I.B.K., E.L., T.P.S.); Tri-Institutional PhD Program in Chemical Biology, New York, New York (I.B.K.); Science for Life Laboratory, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH-Royal Institute of Technology, Solna, Sweden (J.M.S.); Department of Pharmacology and Toxicology, School of Biomedical Sciences, Division of Health Sciences, University of Otago, Dunedin, New Zealand (D.L.H.); and Department of Neurobiology, Care Sciences and Society (NVS), Division for Neurogeriatrics, Center for Alzheimer Research, Karolinska Institutet, Solna, Sweden (T.P.S.)
| | - Thomas P Sakmar
- Laboratory of Chemical Biology and Signal Transduction, The Rockefeller University, New York, New York (I.B.K., E.L., T.P.S.); Tri-Institutional PhD Program in Chemical Biology, New York, New York (I.B.K.); Science for Life Laboratory, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH-Royal Institute of Technology, Solna, Sweden (J.M.S.); Department of Pharmacology and Toxicology, School of Biomedical Sciences, Division of Health Sciences, University of Otago, Dunedin, New Zealand (D.L.H.); and Department of Neurobiology, Care Sciences and Society (NVS), Division for Neurogeriatrics, Center for Alzheimer Research, Karolinska Institutet, Solna, Sweden (T.P.S.)
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Serafin DS, Harris NR, Nielsen NR, Mackie DI, Caron KM. Dawn of a New RAMPage. Trends Pharmacol Sci 2020; 41:249-265. [PMID: 32115276 PMCID: PMC7236817 DOI: 10.1016/j.tips.2020.01.009] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2019] [Revised: 01/24/2020] [Accepted: 01/27/2020] [Indexed: 01/08/2023]
Abstract
Receptor activity-modifying proteins (RAMPs) interact with G-protein-coupled receptors (GPCRs) to modify their functions, imparting significant implications upon their physiological and therapeutic potentials. Resurging interest in identifying RAMP-GPCR interactions has recently been fueled by coevolution studies and orthogonal technological screening platforms. These new studies reveal previously unrecognized RAMP-interacting GPCRs, many of which expand beyond Class B GPCRs. The consequences of these interactions on GPCR function and physiology lays the foundation for new molecular therapeutic targets, as evidenced by the recent success of erenumab. Here, we highlight recent papers that uncovered novel RAMP-GPCR interactions, human RAMP-GPCR disease-causing mutations, and RAMP-related human pathologies, paving the way for a new era of RAMP-targeted drug development.
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Affiliation(s)
- D Stephen Serafin
- Department of Cell Biology and Physiology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Natalie R Harris
- Department of Cell Biology and Physiology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Natalie R Nielsen
- Department of Cell Biology and Physiology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Duncan I Mackie
- Department of Cell Biology and Physiology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Kathleen M Caron
- Department of Cell Biology and Physiology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.
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Abstract
The canonical CGRP receptor is a complex between calcitonin receptor-like receptor (CLR), a family B G-protein-coupled receptor (GPCR) and receptor activity-modifying protein 1 (RAMP1). A third protein, receptor component protein (RCP) is needed for coupling to Gs. CGRP can interact with other RAMP-receptor complexes, particularly the AMY1 receptor formed between the calcitonin receptor (CTR) and RAMP1. Crystal structures are available for the binding of CGRP27-37 [D31,P34,F35] to the extracellular domain (ECD) of CLR and RAMP1; these show that extreme C-terminal amide of CGRP interacts with W84 of RAMP1 but the rest of the analogue interacts with CLR. Comparison with the crystal structure of a fragment of the allied peptide adrenomedullin bound to the ECD of CLR/RAMP2 confirms the importance of the interaction of the ligand C-terminus and the RAMP in determining pharmacology specificity, although the RAMPs probably also have allosteric actions. A cryo-electron microscope structure of calcitonin bound to the full-length CTR associated with Gs gives important clues as to the structure of the complete receptor and suggests that the N-terminus of CGRP makes contact with His5.40b, high on TM5 of CLR. However, it is currently not known how the RAMPs interact with the TM bundle of any GPCR. Major challenges remain in understanding how the ECD and TM domains work together to determine ligand specificity, and how G-proteins influence this and the role of RCP. It seems likely that allosteric mechanisms are particularly important as are the dynamics of the receptors.
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Affiliation(s)
- John Simms
- School of Life and Health Science, Aston University, Birmingham, UK
- Coventry University, Coventry, UK
| | - Sarah Routledge
- School of Life and Health Science, Aston University, Birmingham, UK
| | - Romez Uddin
- School of Life and Health Science, Aston University, Birmingham, UK
| | - David Poyner
- School of Life and Health Science, Aston University, Birmingham, UK.
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Hay DL, Garelja ML, Poyner DR, Walker CS. Update on the pharmacology of calcitonin/CGRP family of peptides: IUPHAR Review 25. Br J Pharmacol 2017; 175:3-17. [PMID: 29059473 DOI: 10.1111/bph.14075] [Citation(s) in RCA: 238] [Impact Index Per Article: 34.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2017] [Revised: 09/27/2017] [Accepted: 09/28/2017] [Indexed: 12/19/2022] Open
Abstract
The calcitonin/CGRP family of peptides includes calcitonin, α and β CGRP, amylin, adrenomedullin (AM) and adrenomedullin 2/intermedin (AM2/IMD). Their receptors consist of one of two GPCRs, the calcitonin receptor (CTR) or the calcitonin receptor-like receptor (CLR). Further diversity arises from heterodimerization of these GPCRs with one of three receptor activity-modifying proteins (RAMPs). This gives the CGRP receptor (CLR/RAMP1), the AM1 and AM2 receptors (CLR/RAMP2 or RAMP3) and the AMY1, AMY2 and AMY3 receptors (CTR/RAMPs1-3 complexes, respectively). Apart from the CGRP receptor, there are only peptide antagonists widely available for these receptors, and these have limited selectivity, thus defining the function of each receptor in vivo remains challenging. Further challenges arise from the probable co-expression of CTR with the CTR/RAMP complexes and species-dependent splice variants of the CTR (CT(a) and CT(b) ). Furthermore, the AMY1(a) receptor is activated equally well by both amylin and CGRP, and the preferred receptor for AM2/IMD has been unclear. However, there are clear therapeutic rationales for developing agents against the various receptors for these peptides. For example, many agents targeting the CGRP system are in clinical trials, and pramlintide, an amylin analogue, is an approved therapy for insulin-requiring diabetes. This review provides an update on the pharmacology of the calcitonin family of peptides by members of the corresponding subcommittee of the International Union of Basic and Clinical Pharmacology and colleagues.
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Affiliation(s)
- Debbie L Hay
- School of Biological Sciences, University of Auckland, Auckland, New Zealand
| | - Michael L Garelja
- School of Biological Sciences, University of Auckland, Auckland, New Zealand
| | - David R Poyner
- School of Life and Health Sciences, Aston University, Birmingham, UK
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Receptor activity-modifying proteins; multifunctional G protein-coupled receptor accessory proteins. Biochem Soc Trans 2016; 44:568-73. [PMID: 27068971 DOI: 10.1042/bst20150237] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2015] [Indexed: 12/22/2022]
Abstract
Receptor activity-modifying proteins (RAMPs) are single pass membrane proteins initially identified by their ability to determine the pharmacology of the calcitonin receptor-like receptor (CLR), a family B G protein-coupled receptor (GPCR). It is now known that RAMPs can interact with a much wider range of GPCRs. This review considers recent developments on the structure of the complexes formed between the extracellular domains (ECDs) of CLR and RAMP1 or RAMP2 as these provide insights as to how the RAMPs direct ligand binding. The range of RAMP interactions is also considered; RAMPs can interact with numerous family B GPCRs as well as examples of family A and family C GPCRs. They influence receptor expression at the cell surface, trafficking, ligand binding and G protein coupling. The GPCR-RAMP interface offers opportunities for drug targeting, illustrated by examples of drugs developed for migraine.
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8
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Bower RL, Hay DL. Amylin structure-function relationships and receptor pharmacology: implications for amylin mimetic drug development. Br J Pharmacol 2016; 173:1883-98. [PMID: 27061187 DOI: 10.1111/bph.13496] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Revised: 03/15/2016] [Accepted: 03/15/2016] [Indexed: 01/19/2023] Open
Abstract
Amylin is an important, but poorly understood, 37 amino acid glucoregulatory hormone with great potential to target metabolic diseases. A working example that the amylin system is one worth developing is the FDA-approved drug used in insulin-requiring diabetic patients, pramlintide. However, certain characteristics of pramlintide pharmacokinetics and formulation leave considerable room for further development of amylin-mimetic compounds. Given that amylin-mimetic drug design and development is an active area of research, surprisingly little is known about the structure/function relationships of amylin. This is largely due to the unfavourable aggregative and solubility properties of the native peptide sequence, which are further complicated by the composition of amylin receptors. These are complexes of the calcitonin receptor with receptor activity-modifying proteins. This review explores what is known of the structure-function relationships of amylin and provides insights that can be drawn from the closely related peptide, CGRP. We also describe how this information is aiding the development of more potent and stable amylin mimetics, including peptide hybrids.
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Affiliation(s)
- Rebekah L Bower
- School of Biological Sciences and Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland, Auckland, New Zealand
| | - Debbie L Hay
- School of Biological Sciences and Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland, Auckland, New Zealand
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Hay DL, Chen S, Lutz TA, Parkes DG, Roth JD. Amylin: Pharmacology, Physiology, and Clinical Potential. Pharmacol Rev 2016; 67:564-600. [PMID: 26071095 DOI: 10.1124/pr.115.010629] [Citation(s) in RCA: 231] [Impact Index Per Article: 28.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Amylin is a pancreatic β-cell hormone that produces effects in several different organ systems. Here, we review the literature in rodents and in humans on amylin research since its discovery as a hormone about 25 years ago. Amylin is a 37-amino-acid peptide that activates its specific receptors, which are multisubunit G protein-coupled receptors resulting from the coexpression of a core receptor protein with receptor activity-modifying proteins, resulting in multiple receptor subtypes. Amylin's major role is as a glucoregulatory hormone, and it is an important regulator of energy metabolism in health and disease. Other amylin actions have also been reported, such as on the cardiovascular system or on bone. Amylin acts principally in the circumventricular organs of the central nervous system and functionally interacts with other metabolically active hormones such as cholecystokinin, leptin, and estradiol. The amylin-based peptide, pramlintide, is used clinically to treat type 1 and type 2 diabetes. Clinical studies in obesity have shown that amylin agonists could also be useful for weight loss, especially in combination with other agents.
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Affiliation(s)
- Debbie L Hay
- School of Biological Sciences, Maurice Wilkins Centre for Molecular Biodiscovery and Centre for Brain Research, University of Auckland, Auckland, New Zealand (D.L.H.); Amylin Pharmaceuticals LLC, San Diego, California (S.C., D.G.P.); Institute of Veterinary Physiology, Institute of Laboratory Animal Sciences and Centre for Integrative Human Physiology, University of Zurich, Zurich, Switzerland (T.A.L.); and Intercept Pharmaceuticals, Inc., San Diego, California (J.D.R.)
| | - Steve Chen
- School of Biological Sciences, Maurice Wilkins Centre for Molecular Biodiscovery and Centre for Brain Research, University of Auckland, Auckland, New Zealand (D.L.H.); Amylin Pharmaceuticals LLC, San Diego, California (S.C., D.G.P.); Institute of Veterinary Physiology, Institute of Laboratory Animal Sciences and Centre for Integrative Human Physiology, University of Zurich, Zurich, Switzerland (T.A.L.); and Intercept Pharmaceuticals, Inc., San Diego, California (J.D.R.)
| | - Thomas A Lutz
- School of Biological Sciences, Maurice Wilkins Centre for Molecular Biodiscovery and Centre for Brain Research, University of Auckland, Auckland, New Zealand (D.L.H.); Amylin Pharmaceuticals LLC, San Diego, California (S.C., D.G.P.); Institute of Veterinary Physiology, Institute of Laboratory Animal Sciences and Centre for Integrative Human Physiology, University of Zurich, Zurich, Switzerland (T.A.L.); and Intercept Pharmaceuticals, Inc., San Diego, California (J.D.R.)
| | - David G Parkes
- School of Biological Sciences, Maurice Wilkins Centre for Molecular Biodiscovery and Centre for Brain Research, University of Auckland, Auckland, New Zealand (D.L.H.); Amylin Pharmaceuticals LLC, San Diego, California (S.C., D.G.P.); Institute of Veterinary Physiology, Institute of Laboratory Animal Sciences and Centre for Integrative Human Physiology, University of Zurich, Zurich, Switzerland (T.A.L.); and Intercept Pharmaceuticals, Inc., San Diego, California (J.D.R.)
| | - Jonathan D Roth
- School of Biological Sciences, Maurice Wilkins Centre for Molecular Biodiscovery and Centre for Brain Research, University of Auckland, Auckland, New Zealand (D.L.H.); Amylin Pharmaceuticals LLC, San Diego, California (S.C., D.G.P.); Institute of Veterinary Physiology, Institute of Laboratory Animal Sciences and Centre for Integrative Human Physiology, University of Zurich, Zurich, Switzerland (T.A.L.); and Intercept Pharmaceuticals, Inc., San Diego, California (J.D.R.)
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Abstract
It is now recognized that G protein-coupled receptors (GPCRs), once considered largely independent functional units, have a far more diverse molecular architecture. Receptor activity-modifying proteins (RAMPs) provide an important example of proteins that interact with GPCRs to modify their function. RAMPs are able to act as pharmacological switches and chaperones, and they can regulate signaling and/or trafficking in a receptor-dependent manner. This review covers recent discoveries in the RAMP field and summarizes the known GPCR partners and functions of RAMPs. We also discuss the first peptide-bound structures of RAMP-GPCR complexes, which give insight into the molecular mechanisms that enable RAMPs to alter the pharmacology and signaling of GPCRs.
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Affiliation(s)
- Debbie L Hay
- School of Biological Sciences and Maurice Wilkins Center, University of Auckland, Auckland 1142, New Zealand;
| | - Augen A Pioszak
- Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73104;
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Walker CS, Hay DL. CGRP in the trigeminovascular system: a role for CGRP, adrenomedullin and amylin receptors? Br J Pharmacol 2013; 170:1293-307. [PMID: 23425327 PMCID: PMC3838677 DOI: 10.1111/bph.12129] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2012] [Revised: 01/21/2013] [Accepted: 01/30/2013] [Indexed: 01/15/2023] Open
Abstract
UNLABELLED The neuropeptide calcitonin gene-related peptide (CGRP) is reported to play an important role in migraine. It is expressed throughout the trigeminovascular system. Antagonists targeting the CGRP receptor have been developed and have shown efficacy in clinical trials for migraine. However, no CGRP antagonist is yet approved for treating this condition. The molecular composition of the CGRP receptor is unusual because it comprises two subunits; one is a GPCR, the calcitonin receptor-like receptor (CLR). This associates with receptor activity-modifying protein (RAMP) 1 to yield a functional receptor for CGRP. However, RAMP1 also associates with the calcitonin receptor, creating a receptor for the related peptide amylin but this also has high affinity for CGRP. Other combinations of CLR or the calcitonin receptor with RAMPs can also generate receptors that are responsive to CGRP. CGRP potentially modulates an array of signal transduction pathways downstream of activation of these receptors, in a cell type-dependent manner. The physiological significance of these signalling processes remains unclear but may be a potential avenue for refining drug design. This complexity has prompted us to review the signalling and expression of CGRP and related receptors in the trigeminovascular system. This reveals that more than one CGRP responsive receptor may be expressed in key parts of this system and that further work is required to determine their contribution to CGRP physiology and pathophysiology. LINKED ARTICLES This article is part of a themed section on Neuropeptides. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2013.170.issue-7.
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Affiliation(s)
- C S Walker
- School of Biological Sciences, University of Auckland, New Zealand; Centre for Brain Research, University of Auckland, Auckland, New Zealand
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