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Wang J, Cui ZJ. Photodynamic Activation of Cholecystokinin 1 Receptor Is Conserved in Mammalian and Avian Pancreatic Acini. Biomedicines 2023. [DOI: https:/doi.org/10.3390/biomedicines11030885] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/19/2023] Open
Abstract
Cholecystokinin 1 receptor (CCK1R) is the only G protein coupled receptor that is activated in type II photodynamic action, but whether this is a property common to both mammalian and avian species is not known. In this work, pancreatic acini were isolated from the rat, mouse, and Peking duck, and photodynamic CCK1R activation was examined. Isolated pancreatic acini were exposed to photosensitizer sulphonated aluminum phthalocyanine (SALPC) and photodynamic action elicited by a brief light-emitting diode (LED 675 nm) pulse (1.5 min); photodynamic CCK1R activation was assessed by Fura-2 fluorescent calcium imaging. Photodynamic action was found to induce persistent calcium oscillations in rat, mouse, and Peking duck pancreatic acini, with the sensitivity order of mouse > rat > Peking duck. Photodynamically-activated CCK1R could be inhibited reversibly by CCK1R antagonist devazepide (1 μM); photodynamic CCK1R activation was blocked by pre-incubation with 1O2 quencher Trolox C (300 µM). The sensitivity of photodynamic CCK1R activation was correlated with the increasing size of the disordered region in intracellular loop 3. These data suggest that photodynamic CCK1R activation is conserved in both mammalian and avian species, as evidenced by the presence of the photodynamic activation motif “YFM” in transmembrane domain 3.
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Affiliation(s)
- Jie Wang
- Institute of Cell Biology, Beijing Normal University, Beijing 100875, China
| | - Zong Jie Cui
- Institute of Cell Biology, Beijing Normal University, Beijing 100875, China
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Wang J, Cui ZJ. Photodynamic Activation of Cholecystokinin 1 Receptor Is Conserved in Mammalian and Avian Pancreatic Acini. Biomedicines 2023; 11:biomedicines11030885. [PMID: 36979864 PMCID: PMC10046250 DOI: 10.3390/biomedicines11030885] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Revised: 03/08/2023] [Accepted: 03/08/2023] [Indexed: 03/18/2023] Open
Abstract
Cholecystokinin 1 receptor (CCK1R) is the only G protein coupled receptor that is activated in type II photodynamic action, but whether this is a property common to both mammalian and avian species is not known. In this work, pancreatic acini were isolated from the rat, mouse, and Peking duck, and photodynamic CCK1R activation was examined. Isolated pancreatic acini were exposed to photosensitizer sulphonated aluminum phthalocyanine (SALPC) and photodynamic action elicited by a brief light-emitting diode (LED 675 nm) pulse (1.5 min); photodynamic CCK1R activation was assessed by Fura-2 fluorescent calcium imaging. Photodynamic action was found to induce persistent calcium oscillations in rat, mouse, and Peking duck pancreatic acini, with the sensitivity order of mouse > rat > Peking duck. Photodynamically-activated CCK1R could be inhibited reversibly by CCK1R antagonist devazepide (1 μM); photodynamic CCK1R activation was blocked by pre-incubation with 1O2 quencher Trolox C (300 µM). The sensitivity of photodynamic CCK1R activation was correlated with the increasing size of the disordered region in intracellular loop 3. These data suggest that photodynamic CCK1R activation is conserved in both mammalian and avian species, as evidenced by the presence of the photodynamic activation motif “YFM” in transmembrane domain 3.
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Chen Y, Wu X, Lai J, Liu Y, Song M, Li F, Gong Q. Molecular characterization and tissue distribution of cholecystokinin and its receptor in Yangtze sturgeon (Acipenser dabryanus) and their response to different feeding conditions. Comp Biochem Physiol A Mol Integr Physiol 2021; 265:111129. [PMID: 34942371 DOI: 10.1016/j.cbpa.2021.111129] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Revised: 12/15/2021] [Accepted: 12/16/2021] [Indexed: 12/22/2022]
Abstract
Yangtze sturgeon (Acipenser dabryanus) is a species endemic to Yangtze River drainage in China and is listed as a critically endangered species on the IUCN Red List. In the present study, cholecystokinin (CCK), one of the most important neuroregulatory digestive genes, and its receptor (CCKr) were identified from the full-length transcriptome analysis of A. dabryanus. The deduced amino acid sequences of CCK and CCKr from A. dabryanus showed structural features common to those in other vertebrates. Gene expression profile analysis showed that CCK and CCKr were universally expressed in different tissues, and both had the highest expression in the brain. Starvation and refeeding significantly regulated the expression levels of CCK and CCKr in the brain, suggesting that CCK and CCKr were involved in feed intake regulation in A. dabryanus as in mammals. In addition, the expression levels of CCK and CCKr under different feeding frequencies were studied. Compared with the control group (fed two times a day), the expression levels of CCK and CCKr in the intestine and brain did not change significantly in the other groups after 8 weeks of rearing, indicating that the feeding frequency might not influence the appetite of A. dabryanus. The present work provides a basis for further investigation into the regulation of feeding in A. dabryanus.
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Affiliation(s)
- Yeyu Chen
- The Fishery Institute of the Sichuan Academy of Agricultural Sciences, Chengdu 611730, China
| | - Xiaoyun Wu
- The Fishery Institute of the Sichuan Academy of Agricultural Sciences, Chengdu 611730, China
| | - Jiansheng Lai
- The Fishery Institute of the Sichuan Academy of Agricultural Sciences, Chengdu 611730, China
| | - Ya Liu
- The Fishery Institute of the Sichuan Academy of Agricultural Sciences, Chengdu 611730, China
| | - Mingjiang Song
- The Fishery Institute of the Sichuan Academy of Agricultural Sciences, Chengdu 611730, China
| | - Feiyang Li
- The Fishery Institute of the Sichuan Academy of Agricultural Sciences, Chengdu 611730, China
| | - Quan Gong
- The Fishery Institute of the Sichuan Academy of Agricultural Sciences, Chengdu 611730, China.
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Mobbs JI, Belousoff MJ, Harikumar KG, Piper SJ, Xu X, Furness SGB, Venugopal H, Christopoulos A, Danev R, Wootten D, Thal DM, Miller LJ, Sexton PM. Structures of the human cholecystokinin 1 (CCK1) receptor bound to Gs and Gq mimetic proteins provide insight into mechanisms of G protein selectivity. PLoS Biol 2021; 19:e3001295. [PMID: 34086670 DOI: 10.1371/journal.pbio.3001295] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2021] [Revised: 06/16/2021] [Accepted: 05/19/2021] [Indexed: 01/08/2023] Open
Abstract
G protein–coupled receptors (GPCRs) are critical regulators of cellular function acting via heterotrimeric G proteins as their primary transducers with individual GPCRs capable of pleiotropic coupling to multiple G proteins. Structural features governing G protein selectivity and promiscuity are currently unclear. Here, we used cryo-electron microscopy (cryo-EM) to determine structures of the cholecystokinin (CCK) type 1 receptor (CCK1R) bound to the CCK peptide agonist, CCK-8 and 2 distinct transducer proteins, its primary transducer Gq, and the more weakly coupled Gs. As seen with other Gq/11–GPCR complexes, the Gq–α5 helix (αH5) bound to a relatively narrow pocket in the CCK1R core. Surprisingly, the backbone of the CCK1R and volume of the G protein binding pocket were essentially equivalent when Gs was bound, with the Gs αH5 displaying a conformation that arises from “unwinding” of the far carboxyl-terminal residues, compared to canonically Gs coupled receptors. Thus, integrated changes in the conformations of both the receptor and G protein are likely to play critical roles in the promiscuous coupling of individual GPCRs. Cryo-EM structures of the G protein-coupled receptor CCK1R bound to the CCK peptide agonist CCK-8 and two distinct transducer proteins – its primary transducer Gq, and the more weakly coupled Gs – reveal unexpected modes of G protein interaction.
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Liu Q, Yang D, Zhuang Y, Croll TI, Cai X, Dai A, He X, Duan J, Yin W, Ye C, Zhou F, Wu B, Zhao Q, Xu HE, Wang MW, Jiang Y. Ligand recognition and G-protein coupling selectivity of cholecystokinin A receptor. Nat Chem Biol 2021; 17:1238-1244. [PMID: 34556862 PMCID: PMC8604728 DOI: 10.1038/s41589-021-00841-3] [Citation(s) in RCA: 43] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2021] [Accepted: 06/24/2021] [Indexed: 02/08/2023]
Abstract
Cholecystokinin A receptor (CCKAR) belongs to family A G-protein-coupled receptors and regulates nutrient homeostasis upon stimulation by cholecystokinin (CCK). It is an attractive drug target for gastrointestinal and metabolic diseases. One distinguishing feature of CCKAR is its ability to interact with a sulfated ligand and to couple with divergent G-protein subtypes, including Gs, Gi and Gq. However, the basis for G-protein coupling promiscuity and ligand recognition by CCKAR remains unknown. Here, we present three cryo-electron microscopy structures of sulfated CCK-8-activated CCKAR in complex with Gs, Gi and Gq heterotrimers, respectively. CCKAR presents a similar conformation in the three structures, whereas conformational differences in the 'wavy hook' of the Gα subunits and ICL3 of the receptor serve as determinants in G-protein coupling selectivity. Our findings provide a framework for understanding G-protein coupling promiscuity by CCKAR and uncover the mechanism of receptor recognition by sulfated CCK-8.
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Affiliation(s)
- Qiufeng Liu
- grid.9227.e0000000119573309The CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
| | - Dehua Yang
- grid.9227.e0000000119573309The CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China ,grid.410726.60000 0004 1797 8419University of Chinese Academy of Sciences, Beijing, China ,grid.9227.e0000000119573309The National Center for Drug Screening, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
| | - Youwen Zhuang
- grid.9227.e0000000119573309The CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
| | - Tristan I. Croll
- grid.5335.00000000121885934Department of Haematology, Cambridge Institute for Medical Research, University of Cambridge, Cambridge, UK
| | - Xiaoqing Cai
- grid.9227.e0000000119573309The National Center for Drug Screening, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
| | - Antao Dai
- grid.9227.e0000000119573309The National Center for Drug Screening, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
| | - Xinheng He
- grid.9227.e0000000119573309The CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China ,grid.410726.60000 0004 1797 8419University of Chinese Academy of Sciences, Beijing, China
| | - Jia Duan
- grid.9227.e0000000119573309The CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China ,grid.410726.60000 0004 1797 8419University of Chinese Academy of Sciences, Beijing, China
| | - Wanchao Yin
- grid.9227.e0000000119573309The CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
| | - Chenyu Ye
- grid.8547.e0000 0001 0125 2443School of Pharmacy, Fudan University, Shanghai, China
| | - Fulai Zhou
- grid.9227.e0000000119573309The CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
| | - Beili Wu
- grid.9227.e0000000119573309The CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China ,grid.410726.60000 0004 1797 8419University of Chinese Academy of Sciences, Beijing, China ,grid.440637.20000 0004 4657 8879School of Life Science and Technology, ShanghaiTech University, Shanghai, China ,grid.9227.e0000000119573309CAS Center for Excellence in Biomacromolecules, Chinese Academy of Sciences, Beijing, China
| | - Qiang Zhao
- grid.410726.60000 0004 1797 8419University of Chinese Academy of Sciences, Beijing, China ,grid.9227.e0000000119573309CAS Center for Excellence in Biomacromolecules, Chinese Academy of Sciences, Beijing, China ,grid.9227.e0000000119573309State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
| | - H. Eric Xu
- grid.9227.e0000000119573309The CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China ,grid.410726.60000 0004 1797 8419University of Chinese Academy of Sciences, Beijing, China ,grid.440637.20000 0004 4657 8879School of Life Science and Technology, ShanghaiTech University, Shanghai, China
| | - Ming-Wei Wang
- grid.9227.e0000000119573309The CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China ,grid.410726.60000 0004 1797 8419University of Chinese Academy of Sciences, Beijing, China ,grid.9227.e0000000119573309The National Center for Drug Screening, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China ,grid.8547.e0000 0001 0125 2443School of Pharmacy, Fudan University, Shanghai, China ,grid.440637.20000 0004 4657 8879School of Life Science and Technology, ShanghaiTech University, Shanghai, China ,grid.8547.e0000 0001 0125 2443School of Basic Medical Sciences, Fudan University, Shanghai, China
| | - Yi Jiang
- grid.9227.e0000000119573309The CAS Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China ,grid.410726.60000 0004 1797 8419University of Chinese Academy of Sciences, Beijing, China
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Abstract
The cholecystokinin 2 receptor (CCK2R) is expressed in the central nervous system and peripheral tissues, playing an important role in higher nervous and gastrointestinal functions, pain sensation, and cancer growth. CCK2R is reversibly activated by cholecystokinin or gastrin, but whether it can be activated permanently is not known. In this work, we found that CCK2R expressed ectopically in CHO-K1 cells was permanently activated in the dark by sulfonated aluminum phthalocyanine (SALPC / AlPcS4, 10-1,000 nM), as monitored by Fura-2 fluorescent calcium imaging. Permanent CCK2R activation was also observed with AlPcS2, but not PcS4. CCK2R previously exposed to SALPC (3 and 10 nM) was sensitized by subsequent light irradiation (> 580 nm, 31.5 mW·cm-2). After the genetically encoded protein photosensitizer mini singlet oxygen generator (miniSOG) was fused to the N-terminus of CCK2R and expressed in CHO-K1 cells, light irradiation (450 nm, 85 mW·cm-2) activated in-frame CCK2R (miniSOG-CCK2R), permanently triggering persistent calcium oscillations blocked by the CCK2R antagonist YM 022 (30 nM). From these data, it is concluded that SALPC is a long-lasting CCK2R agonist in the dark, and CCK2R is photogenetically activated permanently with miniSOG as photosensitizer. These properties of SALPC and CCK2R could be used to study CCK2R physiology and possibly for pain and cancer therapies.
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Tikhonova IG, Gigoux V, Fourmy D. Understanding Peptide Binding in Class A G Protein-Coupled Receptors. Mol Pharmacol 2019; 96:550-561. [PMID: 31436539 DOI: 10.1124/mol.119.115915] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2019] [Accepted: 06/13/2019] [Indexed: 12/13/2022] Open
Abstract
Many physiologic processes are controlled through the activation of G protein-coupled receptors (GPCRs) by regulatory peptides, making peptide GPCRs particularly useful targets for major human diseases such as diabetes and cancer. Peptide GPCRs are also being evaluated as next-generation targets for the development of novel antiparasite agents and insecticides in veterinary medicine and agriculture. Resolution of crystal structures for several peptide GPCRs has advanced our understanding of peptide-receptor interactions and fueled interest in correlating peptide heterogeneity with receptor-binding properties. In this review, the knowledge of recently crystalized peptide-GPCR complexes, previously accumulated peptide structure-activity relationship studies, receptor mutagenesis, and sequence alignment are integrated to better understand peptide binding to the transmembrane cavity of class A GPCRs. Using SAR data, we show that peptide class A GPCRs can be divided into groups with distinct hydrophilic residues. These characteristic residues help explain the preference of a receptor to bind the C-terminal free carboxyl group, the C-terminal amidated group, or the N-terminal ammonium group of peptides.
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Affiliation(s)
- Irina G Tikhonova
- School of Pharmacy, Medical Biology Centre, Queen's University Belfast, Belfast, Northern Ireland, United Kingdom, (I.G.T.) and INSERM ERL1226-Receptology and Therapeutic Targeting of Cancers, Laboratoire de Physique et Chimie des Nano-Objets, CNRS UMR5215-INSA, Université de Toulouse III, Toulouse, France (V.G., D.F.)
| | - Veronique Gigoux
- School of Pharmacy, Medical Biology Centre, Queen's University Belfast, Belfast, Northern Ireland, United Kingdom, (I.G.T.) and INSERM ERL1226-Receptology and Therapeutic Targeting of Cancers, Laboratoire de Physique et Chimie des Nano-Objets, CNRS UMR5215-INSA, Université de Toulouse III, Toulouse, France (V.G., D.F.)
| | - Daniel Fourmy
- School of Pharmacy, Medical Biology Centre, Queen's University Belfast, Belfast, Northern Ireland, United Kingdom, (I.G.T.) and INSERM ERL1226-Receptology and Therapeutic Targeting of Cancers, Laboratoire de Physique et Chimie des Nano-Objets, CNRS UMR5215-INSA, Université de Toulouse III, Toulouse, France (V.G., D.F.)
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Sensfuss U, Kruse T, Skyggebjerg RB, Uldam HK, Vestergaard B, Huus K, Vinther TN, Reinau ME, Schéele S, Clausen TR. Structure–Activity Relationships and Characterization of Highly Selective, Long-Acting, Peptide-Based Cholecystokinin 1 Receptor Agonists. J Med Chem 2019; 62:1407-1419. [DOI: 10.1021/acs.jmedchem.8b01558] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Desai AJ, Dong M, Harikumar KG, Miller LJ. Cholecystokinin-induced satiety, a key gut servomechanism that is affected by the membrane microenvironment of this receptor. Int J Obes Suppl 2016; 6:S22-S27. [PMID: 28685026 DOI: 10.1038/ijosup.2016.5] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The gastrointestinal (GI) tract has a central role in nutritional homeostasis, as location for food ingestion, digestion and absorption, with the gut endocrine system responding to and regulating these events, as well as influencing appetite. One key GI hormone with the full spectrum of these activities is cholecystokinin (CCK), a peptide released from neuroendocrine I cells scattered through the proximal intestine in response to fat and protein, with effects to stimulate gall bladder contraction and pancreatic exocrine secretion, to regulate gastric emptying and intestinal transit, and to induce satiety. There has been interest in targeting the type 1 CCK receptor (CCK1R) for drug development to provide non-caloric satiation as an aid to dieting and weight loss; however, there have been concerns about CCK1R agonists related to side effects and potential trophic impact on the pancreas. A positive allosteric modulator (PAM) of CCK action at this receptor without intrinsic agonist activity could provide a safer and more effective approach to long-term administration. In addition, CCK1R stimulus-activity coupling has been shown to be negatively affected by excess membrane cholesterol, a condition described in the metabolic syndrome, thereby potentially interfering with an important servomechanism regulating appetite. A PAM targeting this receptor could also potentially correct the negative impact of cholesterol on CCK1R function. We will review the molecular basis for binding natural peptide agonist, binding and action of small molecules within the allosteric pocket, and the impact of cholesterol. Novel strategies for taking advantage of this receptor for the prevention and management of obesity will be reviewed.
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Affiliation(s)
- A J Desai
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Scottsdale, AZ, USA
| | - M Dong
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Scottsdale, AZ, USA
| | - K G Harikumar
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Scottsdale, AZ, USA
| | - L J Miller
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Scottsdale, AZ, USA
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Chipot C. Milestones in the Activation of a G Protein-Coupled Receptor. Insights from Molecular-Dynamics Simulations into the Human Cholecystokinin Receptor-1. J Chem Theory Comput 2015; 4:2150-9. [PMID: 26620486 DOI: 10.1021/ct800313k] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Activation of G protein-coupled receptors (GPCRs) obeys an allosteric mechanism triggered by ligand binding. To understand how the signal is transduced in the cell, identification of the milestones paving the pathway between the active and the inactive states of the receptor is necessary. A model of the human cholecystokinin receptor-1 (CCK1R) has been proposed recently. The complex formed by CCK1R and an agonist ligand will serve as a paradigm of an active conformation to capture milestones in GPCR activation. To reach this goal, assuming microreversibility, the initial step toward the inactivation of CCK1R was modeled using free energy calculations, whereby the ligand is removed from the binding pocket. However accurate the reproduction of the experimental affinity constant, this simulation only represents an embryonic stage of the inactivation process. Starting from the apo receptor, an unprecedented 0.1-μs molecular dynamics trajectory was generated, bereft of experimental biases, bringing into the light key events in the inactivation of CCK1R, chief among which the hydration of its internal cavity, concomitant with the spatial rearrangement of the transmembrane helical segments. Hydration is intimately related to the isomerization of the highly conserved residue W326 of helix VI, acting as a two-state toggle switch, and of residue M121 of helix III. In the active state, the former residue obstructs the crevice, thereby preventing water leakage, which would otherwise trigger the disruption of an ionic lock between helices II and III involving the signature E/DRY motif ubiquitous to GPCRs.
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Affiliation(s)
- Christophe Chipot
- Equipe de dynamique des assemblages membranaires, UMR No 7565, Nancy Université BP 239, 54506 Vandœuvre-lès-Nancy cedex, France
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Tinoco A, Valenciano A, Gómez-Boronat M, Blanco A, Nisembaum L, De Pedro N, Delgado M. Two cholecystokinin receptor subtypes are identified in goldfish, being the CCKAR involved in the regulation of intestinal motility. Comp Biochem Physiol A Mol Integr Physiol 2015; 187:193-201. [DOI: 10.1016/j.cbpa.2015.05.027] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2015] [Revised: 05/28/2015] [Accepted: 05/31/2015] [Indexed: 12/17/2022]
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Abstract
Transmembrane helical segments (TMs) can be classified into two groups of so-called ‘simple’ and ‘complex’ TMs. Whereas the first group represents mere hydrophobic anchors with an overrepresentation of aliphatic hydrophobic residues that are likely attributed to convergent evolution in many cases, the complex ones embody ancestral information and tend to have structural and functional roles beyond just membrane immersion. Hence, the sequence homology concept is not applicable on simple TMs. In practice, these simple TMs can attract statistically significant but evolutionarily unrelated hits during similarity searches (whether through BLAST- or HMM-based approaches). This is especially problematic for membrane proteins that contain both globular segments and TMs. As such, we have developed the transmembrane helix: simple or complex (TMSOC) webserver for the identification of simple and complex TMs. By masking simple TM segments in seed sequences prior to sequence similarity searches, the false-discovery rate decreases without sacrificing sensitivity. Therefore, TMSOC is a novel and necessary sequence analytic tool for both the experimentalists and the computational biology community working on membrane proteins. It is freely accessible at http://tmsoc.bii.a-star.edu.sg or available for download.
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Affiliation(s)
- Wing-Cheong Wong
- Bioinformatics Institute (BII), Agency for Science, Technology and Research (A*STAR), 30 Biopolis Street, #07-01, Matrix, Singapore 138671, School of Biological Sciences (SBS), Nanyang Technological University (NTU), 60 Nanyang Drive, Singapore 637551, Department of Biological Sciences (DBS), National University of Singapore (NUS), 8 Medical Drive, Singapore 117597 and School of Computer Engineering (SCE), Nanyang Technological University (NTU), 50 Nanyang Drive, Singapore 637553
- *To whom correspondence should be addressed. Tel: +65 64788305; Fax: +65 64789047;
| | - Sebastian Maurer-Stroh
- Bioinformatics Institute (BII), Agency for Science, Technology and Research (A*STAR), 30 Biopolis Street, #07-01, Matrix, Singapore 138671, School of Biological Sciences (SBS), Nanyang Technological University (NTU), 60 Nanyang Drive, Singapore 637551, Department of Biological Sciences (DBS), National University of Singapore (NUS), 8 Medical Drive, Singapore 117597 and School of Computer Engineering (SCE), Nanyang Technological University (NTU), 50 Nanyang Drive, Singapore 637553
| | - Georg Schneider
- Bioinformatics Institute (BII), Agency for Science, Technology and Research (A*STAR), 30 Biopolis Street, #07-01, Matrix, Singapore 138671, School of Biological Sciences (SBS), Nanyang Technological University (NTU), 60 Nanyang Drive, Singapore 637551, Department of Biological Sciences (DBS), National University of Singapore (NUS), 8 Medical Drive, Singapore 117597 and School of Computer Engineering (SCE), Nanyang Technological University (NTU), 50 Nanyang Drive, Singapore 637553
| | - Frank Eisenhaber
- Bioinformatics Institute (BII), Agency for Science, Technology and Research (A*STAR), 30 Biopolis Street, #07-01, Matrix, Singapore 138671, School of Biological Sciences (SBS), Nanyang Technological University (NTU), 60 Nanyang Drive, Singapore 637551, Department of Biological Sciences (DBS), National University of Singapore (NUS), 8 Medical Drive, Singapore 117597 and School of Computer Engineering (SCE), Nanyang Technological University (NTU), 50 Nanyang Drive, Singapore 637553
- *To whom correspondence should be addressed. Tel: +65 64788305; Fax: +65 64789047;
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Cawston EE, Lam PCH, Harikumar KG, Dong M, Ball AM, Augustine ML, Akgün E, Portoghese PS, Orry A, Abagyan R, Sexton PM, Miller LJ. Molecular basis for binding and subtype selectivity of 1,4-benzodiazepine antagonist ligands of the cholecystokinin receptor. J Biol Chem 2012; 287:18618-35. [PMID: 22467877 DOI: 10.1074/jbc.m111.335646] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Allosteric binding pockets in peptide-binding G protein-coupled receptors create opportunities for the development of small molecule drugs with substantial benefits over orthosteric ligands. To gain insights into molecular determinants for this pocket within type 1 and 2 cholecystokinin receptors (CCK1R and CCK2R), we prepared a series of receptor constructs in which six distinct residues in TM2, -3, -6, and -7 were reversed. Two novel iodinated CCK1R- and CCK2R-selective 1,4-benzodiazepine antagonists, differing only in stereochemistry at C3, were used. When all six residues within CCK1R were mutated to corresponding CCK2R residues, benzodiazepine selectivity was reversed, yet peptide binding selectivity was unaffected. Detailed analysis, including observations of gain of function, demonstrated that residues 6.51, 6.52, and 7.39 were most important for binding the CCK1R-selective ligand, whereas residues 2.61 and 7.39 were most important for binding CCK2R-selective ligand, although the effect of substitution of residue 2.61 was likely indirect. Ligand-guided homology modeling was applied to wild type receptors and those reversing benzodiazepine binding selectivity. The models had high predictive power in enriching known receptor-selective ligands from related decoys, indicating a high degree of precision in pocket definition. The benzodiazepines docked in similar poses in both receptors, with C3 urea substituents pointing upward, whereas different stereochemistry at C3 directed the C5 phenyl rings and N1 methyl groups into opposite orientations. The geometry of the binding pockets and specific interactions predicted for ligand docking in these models provide a molecular framework for understanding ligand selectivity at these receptor subtypes. Furthermore, the strong predictive power of these models suggests their usefulness in the discovery of lead compounds and in drug development programs.
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Affiliation(s)
- Erin E Cawston
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Scottsdale, Arizona 85259, USA
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14
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Fanelli F, De Benedetti PG. Update 1 of: computational modeling approaches to structure-function analysis of G protein-coupled receptors. Chem Rev 2011; 111:PR438-535. [PMID: 22165845 DOI: 10.1021/cr100437t] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Francesca Fanelli
- Dulbecco Telethon Institute, University of Modena and Reggio Emilia, via Campi 183, 41125 Modena, Italy.
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15
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Pavan MV, Lassiani L, Berti F, Stefancich G, Ciogli A, Gasparrini F, Mennuni L, Ferrari F, Escrieut C, Marco E, Makovec F, Fourmy D, Varnavas A. New Anthranilic Acid Based Antagonists with High Affinity and Selectivity for the Human Cholecystokinin Receptor 1 (hCCK1-R). J Med Chem 2011; 54:5769-85. [DOI: 10.1021/jm200438b] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Michela V. Pavan
- Department of Chemical and Pharmaceutical Sciences, University of Trieste, P.le Europa 1, 34127 Trieste, Italy
| | - Lucia Lassiani
- Department of Chemical and Pharmaceutical Sciences, University of Trieste, P.le Europa 1, 34127 Trieste, Italy
| | - Federico Berti
- Department of Chemical and Pharmaceutical Sciences, University of Trieste, Via Giorgieri 1, 34127 Trieste, Italy
| | - Giorgio Stefancich
- Department of Chemical and Pharmaceutical Sciences, University of Trieste, P.le Europa 1, 34127 Trieste, Italy
| | - Alessia Ciogli
- Department of Chemistry and Technology of Biologically Active Substances, University “La Sapienza”, P.le Aldo Moro 5, 00185 Rome, Italy
| | - Francesco Gasparrini
- Department of Chemistry and Technology of Biologically Active Substances, University “La Sapienza”, P.le Aldo Moro 5, 00185 Rome, Italy
| | - Laura Mennuni
- Rottapharm—Madaus SpA, Via Valosa di Sopra 7, 20052 Monza, Italy
| | - Flora Ferrari
- Rottapharm—Madaus SpA, Via Valosa di Sopra 7, 20052 Monza, Italy
| | - Chantal Escrieut
- Université de Toulouse 3, EA 4552, I2MC, 1 Avenue Jean Poulhès, 31432 Toulouse, France
| | - Esther Marco
- Université de Toulouse 3, EA 4552, I2MC, 1 Avenue Jean Poulhès, 31432 Toulouse, France
| | | | - Daniel Fourmy
- Université de Toulouse 3, EA 4552, I2MC, 1 Avenue Jean Poulhès, 31432 Toulouse, France
| | - Antonio Varnavas
- Department of Chemical and Pharmaceutical Sciences, University of Trieste, P.le Europa 1, 34127 Trieste, Italy
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16
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Staljanssens D, Azari EK, Christiaens O, Beaufays J, Lins L, Van Camp J, Smagghe G. The CCK(-like) receptor in the animal kingdom: functions, evolution and structures. Peptides 2011; 32:607-19. [PMID: 21167241 DOI: 10.1016/j.peptides.2010.11.025] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/15/2010] [Revised: 11/27/2010] [Accepted: 11/30/2010] [Indexed: 01/09/2023]
Abstract
In this review, the cholecystokinin (CCK)(-like) receptors throughout the animal kingdom are compared on the level of physiological functions, evolutionary basis and molecular structure. In vertebrates, the CCK receptor is an important member of the G-protein coupled receptors as it is involved in the regulation of many physiological functions like satiety, gastrointestinal motility, gastric acid secretion, gall bladder contraction, pancreatic secretion, panic, anxiety and memory and learning processes. A homolog for this receptor is also found in nematodes and arthropods, called CK receptor and sulfakinin (SK) receptor, respectively. These receptors seem to have evolved from a common ancestor which is probably still closely related to the nematode CK receptor. The SK receptor is more closely related to the CCK receptor and seems to have similar functions. A molecular 3D-model for the CCK receptor type 1 has been built together with the docking of the natural ligands for the CCK and SK receptors in the CCK receptor type 1. These molecular models can help to study ligand-receptor interactions, that can in turn be useful in the development of new CCK(-like) receptor agonists and antagonists with beneficial health effects in humans or potential for pest control.
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Affiliation(s)
- Dorien Staljanssens
- Department of Crop Protection, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium
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17
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Peeters MC, Westen GJP, Guo D, Wisse LE, Muller CE, Beukers MW, IJzerman AP. GPCR structure and activation: an essential role for the first extracellular loop in activating the adenosine A
2B
receptor. FASEB J 2010; 25:632-43. [DOI: 10.1096/fj.10-164319] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Miriam C. Peeters
- Division of Medicinal ChemistryLeiden/Amsterdam Centre for Drug ResearchLeiden UniversityLeidenThe Netherlands
| | - Gerard J. P. Westen
- Division of Medicinal ChemistryLeiden/Amsterdam Centre for Drug ResearchLeiden UniversityLeidenThe Netherlands
| | - Dong Guo
- Division of Medicinal ChemistryLeiden/Amsterdam Centre for Drug ResearchLeiden UniversityLeidenThe Netherlands
| | - Lisanne E. Wisse
- Division of Medicinal ChemistryLeiden/Amsterdam Centre for Drug ResearchLeiden UniversityLeidenThe Netherlands
| | - Christa E. Muller
- PharmaCenter BonnPharmaceutical InstitutePharmaceutical Chemistry IPharmaceutical Sciences Bonn (PSB)University of BonnBonnGermany
| | - Margot W. Beukers
- Division of Medicinal ChemistryLeiden/Amsterdam Centre for Drug ResearchLeiden UniversityLeidenThe Netherlands
| | - Adriaan P. IJzerman
- Division of Medicinal ChemistryLeiden/Amsterdam Centre for Drug ResearchLeiden UniversityLeidenThe Netherlands
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18
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Iturrioz X, Gerbier R, Leroux V, Alvear-Perez R, Maigret B, Llorens-Cortes C. By interacting with the C-terminal Phe of apelin, Phe255 and Trp259 in helix VI of the apelin receptor are critical for internalization. J Biol Chem 2010; 285:32627-37. [PMID: 20675385 DOI: 10.1074/jbc.m110.127167] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Apelin is the endogenous ligand of the orphan seven-transmembrane domain (TM) G protein-coupled receptor APJ. Apelin is involved in the regulation of body fluid homeostasis and cardiovascular functions. We previously showed the importance of the C-terminal Phe of apelin 17 (K17F) in the hypotensive activity of this peptide. Here, we show either by deleting the Phe residue (K16P) or by substituting it by an Ala (K17A), that it plays a crucial role in apelin receptor internalization but not in apelin binding or in Gα(i)-protein coupling. Then we built a homology three-dimensional model of the human apelin receptor using the cholecystokinin receptor-1 model as a template, and we subsequently docked K17F into the binding site. We visualized a hydrophobic cavity at the bottom of the binding pocket in which the C-terminal Phe of K17F was embedded by Trp(152) in TMIV and Trp(259) and Phe(255) in TMVI. Using molecular modeling and site-directed mutagenesis studies, we further showed that Phe(255) and Trp(259) are key residues in triggering receptor internalization without playing a role in apelin binding or in Gα(i)-protein coupling. These findings bring new insights into apelin receptor activation and show that Phe(255) and Trp(259), by interacting with the C-terminal Phe of the pyroglutamyl form of apelin 13 (pE13F) or K17F, are crucial for apelin receptor internalization.
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Affiliation(s)
- Xavier Iturrioz
- INSERM, U691, Collège de France, Université Pierre et Marie-Curie Paris 6, Paris FR-75005, France
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19
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Abstract
The G protein coupled receptors belong to the largest group of membrane proteins that regulates many essential physiological properties and represents an important class of drug targets. In this chapter, we show how the synergy between a laboratory experiment and computational modeling leads to structural delineation of the ligand binding pocket and how the knowledge of ligand-protein interactions is used for rational local and global drug design in which the structural knowledge of a particular receptor and its ligands is used for drug design of this particular GPCR and others.
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Affiliation(s)
- Irina G Tikhonova
- INSERM, Institut National de la Santé et de la Recherche Médicale, Université de Toulouse 3, Toulouse, France.
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20
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Dong M, Lam PCH, Pinon DI, Abagyan R, Miller LJ. Elucidation of the molecular basis of cholecystokinin Peptide docking to its receptor using site-specific intrinsic photoaffinity labeling and molecular modeling. Biochemistry 2009; 48:5303-12. [PMID: 19441839 DOI: 10.1021/bi9004705] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
G protein-coupled receptors represent the largest family of receptors and the major target of current drug development efforts. Understanding of the mechanisms of ligand binding and activation of these receptors remains limited, despite recent advances in structural determination of family members. This work focuses on the use of photoaffinity labeling and molecular modeling to elucidate the structural basis of binding a natural peptide ligand to a family A G protein-coupled receptor, the type 1 cholecystokinin receptor. Two photolabile cholecystokinin analogues were developed and characterized as representing high-affinity, fully biologically active probes with sites of covalent attachment at positions 28 and 31. The sites of receptor labeling were identified by purification, proteolytic peptide mapping, and radiochemical sequencing of labeled wild-type and mutant cholecystokinin receptors. The position 28 probe labeled second extracellular loop residue Leu(199), while the position 31 probe labeled first extracellular loop residue Phe(107). Along with five additional spatial approximation constraints coming from previous photoaffinity labeling studies and 12 distance restraints from fluorescence resonance energy transfer studies, these were built into two homology models of the cholecystokinin receptor, based on the recent crystal structures of the beta2-adrenergic receptor and A2a-adenosine receptor. The resultant agonist ligand-occupied receptor models fully accommodate all existing experimental data and represent the best refined models of a peptide hormone receptor in this important family.
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Affiliation(s)
- Maoqing Dong
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Scottsdale, Arizona 85259, USA
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21
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Kumar M, Reeve JR, Hu W, Miller LJ, Keire DA. The micelle-associated 3D structures of Boc-Y(SO3)-Nle-G-W-Nle-D-2-phenylethylester (JMV-180) and CCK-8(s) share conformational elements of a calculated CCK1 receptor-bound model. J Med Chem 2008; 51:3742-54. [PMID: 18540665 DOI: 10.1021/jm701401j] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
JMV-180 ( 1) and CCK-8(s) are high affinity ligands at the CCK 1 receptor that have similar and different actions via this receptor. Here we calculate the tertiary structure of 1 or CCK-8(s) in the presence of dodecylphosphocholine micelles at pH 5.0 and 35 degrees C from 2D (1)H NMR data recorded at 600 MHz. The NMR derived 3D structures of 1 and CCK-8(s) share a common type I beta-turn around residues Nle3/M3 and G4 and diverge from each other structurally at the N- and C-termini. The fluorescence and circular dichroism spectral properties of these peptides are consistent with their NMR derived structures. The structures determined in the presence of DPC micelles are compared to available models of 1 or CCK-8(s) bound to the CCK 1 receptor. For CCK and 1, these comparisons show that DPC micelle associated structures duplicate some important aspects of the models calculated from cross-linking derived constraints at the CCK 1 receptor.
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Affiliation(s)
- Mohanraja Kumar
- CURE: Digestive Diseases Research Center, VA Greater Los Angeles Healthcare System, Los Angeles, California 90073, USA
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22
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de Graaf C, Foata N, Engkvist O, Rognan D. Molecular modeling of the second extracellular loop of G-protein coupled receptors and its implication on structure-based virtual screening. Proteins 2008; 71:599-620. [PMID: 17972285 DOI: 10.1002/prot.21724] [Citation(s) in RCA: 80] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The current study describes the validation of high-throughput modeling procedures for the construction of the second extracellular loop (ecl2) of all nonolfactory human G Protein-coupled receptors. Our modeling flowchart is based on the alignment of essential residues determining the particular ecl2 fold observed in the bovine rhodopsin (bRho) crystal structure. For a set of GPCR targets, the dopamine D2 receptor (DRD2), adenosine A3 receptor (AA3R), and the thromboxane A2 receptor (TA2R), the implications of including ecl2 atomic coordinates is evaluated in terms of structure-based virtual screening accuracy: the suitability of the 3D models to distinguish between known antagonists and randomly chosen decoys using automated docking approaches. The virtual screening results of different models describing increasingly exhaustive receptor representations (seven helices only, seven helices and ecl2 loop, full model) have been compared. Explicit modeling of the ecl2 loop was found to be important in only one of three test cases whereas a loopless model was shown to be accurate enough in the two other receptors. An exhaustive comparison of ecl2 loops of 365 receptors to that of bRho suggests that explicit ecl2 loop modeling should be reserved to receptors where loop building can be guided by experimental restraints.
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Affiliation(s)
- Chris de Graaf
- Bioinformatics of the Drug, CNRS UMR 7175-LC1, Université Louis Pasteur Strasbourg I, Illkirch F-67401, France
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23
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Bu L, Michino M, Wolf RM, Brooks CL. Improved model building and assessment of the Calcium-sensing receptor transmembrane domain. Proteins 2008; 71:215-26. [DOI: 10.1002/prot.21685] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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24
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Toumi-Maouche A, Maouche B, Taïri-Kellou S, El-Aoufi S, Martín-Martínez M, González-Muñiz R, Fourmy D, Maigret B. Exploring the binding pocket for pyridopyrimidine ligands at the CCK1 receptor by molecular docking. J Mol Model 2008; 14:303-14. [PMID: 18286312 DOI: 10.1007/s00894-008-0271-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2007] [Accepted: 01/11/2008] [Indexed: 10/22/2022]
Abstract
Pyridopyrimidine-based analogues are among the most highly potent and selective antagonists of cholecystokinin receptor subtype-1 (CCK1R) described to date. To better understand the structural and chemical features responsible for the recognition mechanism, and to explore the binding pocket of these compounds, we performed automated molecular docking using GOLD2.2 software on some derivatives with structural diversity, and propose a putative binding conformation for each compound. The docking protocol was guided by the key role of the Asn333 residue, as revealed by site directed mutagenesis studies. The results suggest two putative binding modes located in the same pocket. Both are characterized by interaction with the main residues revealed by experiment, Asn333 and Arg336, and differ in the spatial position of the Boc-Trp moiety of these compounds. Hydrophobic contacts with residues Thr117, Phe107, Ile352 and Ile329 are also in agreement with experimental data. Despite the poor correlation obtained between the estimated binding energies and the experimental activity, the proposed models allow us to suggest a plausible explanation of the observed binding data in accordance with chemical characteristics of the compounds, and also to explain the observed diastereoselectivity of this family of antagonists towards CCK1R. The most reasonable selected binding conformations could be the starting point for future studies. Figure Superimposition of the two putative binding conformations revealed by molecular docking for pyridopyrimidine-based CCK1 antagonists.
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25
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Foucaud M, Archer-Lahlou E, Marco E, Tikhonova IG, Maigret B, Escrieut C, Langer I, Fourmy D. Insights into the binding and activation sites of the receptors for cholecystokinin and gastrin. ACTA ACUST UNITED AC 2008; 145:17-23. [DOI: 10.1016/j.regpep.2007.09.024] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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26
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De Luca S, De Capua A, Saviano M, Della Moglie R, Aloj L, Tarallo L, Pedone C, Morelli G. Synthesis and biological evaluation of cyclic and branched peptide analogues as ligands for cholecystokinin type 1 receptor. Bioorg Med Chem 2007; 15:5845-53. [PMID: 17562367 DOI: 10.1016/j.bmc.2007.05.067] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2007] [Revised: 05/22/2007] [Accepted: 05/30/2007] [Indexed: 11/28/2022]
Abstract
A library of cyclic CCK8 analogues, containing unnatural amino acids in the peptide sequence, is prepared using solid-phase synthesis. The structure of these cyclic peptides is based on a previously synthesised compound, cyclo-CCK8, selective for CCK(1) receptor. Structure-activity investigations are performed by evaluating the binding properties of the new analogues. In particular, the binding ability of the cyclic CCK8 analogues is tested by nuclear medicine studies on cell line transfected with CCK(1) receptor. Compounds named cyclo-A4-cyclo-A7 show binding constant in the range 6.0-8.0 microM, with an improved affinity over the previous described cyclo-CCK8, but almost comparable IC(50) values among new analogues towards CCK(1) were obtained.
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Affiliation(s)
- Stefania De Luca
- Istituto di Biostrutture e Bioimmagini CNR, & Centro Interuniversitario per la Ricerca sui Peptidi Bioattivi (CIRPeB), via Mezzocannone, Napoli, Italy
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27
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Tikhonova IG, Sum CS, Neumann S, Thomas CJ, Raaka BM, Costanzi S, Gershengorn MC. Bidirectional, iterative approach to the structural delineation of the functional "chemoprint" in GPR40 for agonist recognition. J Med Chem 2007; 50:2981-9. [PMID: 17552505 PMCID: PMC3592210 DOI: 10.1021/jm0614782] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
GPR40, free fatty acid receptor 1 (FFAR1), is a member of the GPCR superfamily and a possible target for the treatment of type 2 diabetes. In this work, we conducted a bidirectional iterative investigation, including computational modeling and site-directed mutagenesis, aimed at delineating amino acid residues forming the functional "chemoprint" of GPR40 for agonist recognition. The computational and experimental studies revolved around the recognition of the potent synthetic agonist GW9508. Our experimentally supported model suggested that H137(4.56), R183(5.39), N244(6.55), and R258(7.35) are directly involved in interactions with the ligand. We have proposed a polarized NH-pi interaction between H137(4.56) and GW9508 as one of the contributing forces leading to the high potency of GW9508. The modeling approach presented in this work provides a general strategy for the exploration of receptor-ligand interactions in G-protein coupled receptors beginning prior to acquisition of experimental data.
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Affiliation(s)
- Irina G. Tikhonova
- Laboratory of Biological Modeling, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA
| | - Chi Shing Sum
- Clinical Endocrinology Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA
| | - Susanne Neumann
- Clinical Endocrinology Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA
| | - Craig J. Thomas
- Chemical Biology Core Facility, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA
| | - Bruce M. Raaka
- Clinical Endocrinology Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA
| | - Stefano Costanzi
- Laboratory of Biological Modeling, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA
- Corresponding authors. (S.C.) . Phone: 301-451-7353. Fax: 301-443-8000. (M.C.G.) . Phone and Fax: 301-496-4128
| | - Marvin C. Gershengorn
- Clinical Endocrinology Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA
- Corresponding authors. (S.C.) . Phone: 301-451-7353. Fax: 301-443-8000. (M.C.G.) . Phone and Fax: 301-496-4128
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Abstract
The field of cholecystokinin (CCK) stimulation of exocrine pancreatic secretion has experienced major changes in the recent past. This review attempts to summarize the present status of the field. CCK production in the intestinal I cells, the molecular forms of CCK produced and subsequently circulated in the blood, the presence or absence of CCK receptors on the isolated pancreatic acinar cells and the associated signaling for acinar cell secretion, and the actual circuits and sites of action for CCK regulation of exocrine pancreatic secretion in vivo are reviewed in different animal species with an emphasis on birds, rodents, and humans. Clear differences in the relative importance of neural and direct modes of CCK action on pancreatic acinar cells were identified. Rodents seem to be endowed with both modes of action, whereas in humans the neural mode may predominate. In birds, such as duck, the direct mode needs further assistance from pituitary adenylate cyclase-activating peptide/VIP receptors. However, much further work needs to be directed to the neural mode to map out all sites of CCK action and details of the full circuits, and we foresee a major revival for this field of research in the near future.
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Affiliation(s)
- Bi Jue Wang
- Institute of Cell Biology, Beijing Normal University, Beijing 100875, China
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29
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Chipot C, Mark AE, Pande VS, Simonson T. Applications of Free Energy Calculations to Chemistry and Biology. In: Chipot C, Pohorille A, editors. Free Energy Calculations. Berlin: Springer Berlin Heidelberg; 2007. pp. 463-501. [DOI: 10.1007/978-3-540-38448-9_13] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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30
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De Luca S, Saviano M, Della Moglie R, Digilio G, Bracco C, Aloj L, Tarallo L, Pedone C, Morelli G. Conformationally constrained CCK8 analogues obtained from a rationally designed peptide library as ligands for cholecystokinin type B receptor. ChemMedChem 2006; 1:997-1006. [PMID: 16915602 DOI: 10.1002/cmdc.200600054] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
A library of 14 cyclic peptide analogues derived from the octapeptide C-terminal sequence of the human cholecystokinin hormone (CCK(26-33), or CCK8) was designed, synthesized, and characterized. The 14 peptide analogues were rationally designed to specifically interact with the CCK type B receptor (CCK(B)-R) on the basis of the structure of the bimolecular complex between CCK8 and the third extracellular loop of CCK(B)-R, namely CCK(B)-R(352-379). The rational design of new ligands for CCK(B)-R has relied on stabilization by cyclic constraints of the structural motifs that bring the key residues of the ligand (especially Trp 30, Met 31, and Phe 33) in the proper spatial orientation for optimal interaction with the receptor. The binding affinity of the new ligands for CCK(B)-R was assessed by displacement experiments of (111)In-radiolabeled CCK8 in cells that overexpress the CCK(B) receptor. The new ligands generally showed binding affinities lower than that of parent CCK8, with the best compounds having IC50 values around 10 microM. Structure-activity relationship data show that preservation of the Trp 30-Met 31 motif is essential and that the Phe 33 side chain must be present. NMR conformational studies of the compound with maximal binding affinity (cyclo-B11, IC50=11 microM) in DPC micelles shows that this compound presents a turn-like conformation centered at the Trp 30-Met 31 segment, as planned by rational design. Such a conformation is stabilized by its interaction with the micelle rather than by the cyclic constraint.
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Affiliation(s)
- Stefania De Luca
- Istituto di Biostrutture e Bioimmagini-CNR & Centro Interuniversitario per la Ricerca sui Peptidi Bioattivi (CIRPeB) Via Mezzocannone 16, 80134 Napoli, Italy
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31
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Abstract
Cholecystokinin and gastrin receptors (CCK1R and CCK2R) are G protein-coupled receptors that have been the subject of intensive research in the last 10 years with corresponding advances in the understanding of their functioning and physiology. In this review, we first describe general properties of the receptors, such as the different signaling pathways used to exert short- and long-term effects and the structural data that explain their binding properties, activation, and regulation. We then focus on peripheral cholecystokinin receptors by describing their tissue distribution and physiological actions. Finally, pathophysiological peripheral actions of cholecystokinin receptors and their relevance in clinical disorders are reviewed.
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Affiliation(s)
- Marlène Dufresne
- Institut National de la Santé et de la Recherche Médicale U. 531, Institut Louis Bugnard, Centre Hospitalier Universitaire Rangueil, France
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De Luca S, Saviano M, Lassiani L, Yannakopoulou K, Stefanidou P, Aloj L, Morelli G, Varnavas A. Anthranilic Acid Based CCK1 Receptor Antagonists and CCK-8 Have a Common Step in Their “Receptor Desmodynamic Processes”. J Med Chem 2006; 49:2456-62. [PMID: 16610788 DOI: 10.1021/jm051050n] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The interaction between the 1-47 N-terminus of the CCK(1)-R and the anthranilic acid based antagonists has been investigated by fluorescence spectroscopy. These antagonists interact with W39 of the N-terminal domain of the CCK(1)-R like that of the endogenous ligand CCK-8. This specific interaction was not found in other nonpeptide ligands of the CCK(1)-R. Conformational studies, using NMR and energy minimization procedures, have allowed formulation of a new hypothesis on the CCK(1)-R binding mode of the anthranilic antagonists.
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Affiliation(s)
- Stefania De Luca
- Interuniversity Research Center on Bioactive Peptides (CIRPeB), University of Naples Federico II, and Institute of Biostructures and Bioimaging of CNR, Via Mezzocannone, 16 I-80134 Naples, Italy
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Hénin J, Maigret B, Tarek M, Escrieut C, Fourmy D, Chipot C. Probing a model of a GPCR/ligand complex in an explicit membrane environment: the human cholecystokinin-1 receptor. Biophys J 2005; 90:1232-40. [PMID: 16326901 PMCID: PMC1367274 DOI: 10.1529/biophysj.105.070599] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
A three-dimensional model structure of a complex formed by a G-protein-coupled receptor (GPCR) and an agonist ligand is probed and refined using molecular-dynamics simulations and free energy calculations in a realistic environment. The model of the human receptor of cholecystokinin associated to agonist ligand CCK9 was obtained from a synergistic procedure combining site-directed mutagenesis experiments and in silico modeling. The 31-ns molecular-dynamics simulation in an explicit membrane environment indicates that both the structure of the receptor and its interactions with the ligand are robust. Whereas the secondary structure of the alpha-helix bundle is well preserved, the region of the intracellular loops exhibits a significant flexibility likely to be ascribed to the absence of G-protein subunits in the model. New insight into the structural features of the binding pocket is gained, in particular, the interplay of the ligand with both the receptor and internal water molecules. Water-mediated interactions are shown to participate in the binding, hence, suggesting additional site-directed mutagenesis experiments. Accurate free energy calculations on mutated ligands provide differences in the receptor-ligand binding affinity, thus offering a direct, quantitative comparison to experiment. We propose that this detailed consistency-checking procedure be used as a routine refinement step of in vacuo GPCR models, before further investigation and application to structure-based drug design.
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Affiliation(s)
- Jérôme Hénin
- Equipe de Dynamique des Assemblages Membranaires, UMR CNRS/UHP 7565, Institut Nancéien de Chimie Moléculaire, Université Henri Poincaré, Vandoeuvre-lès-Nancy, France
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McClure K, Hack M, Huang L, Sehon C, Morton M, Li L, Barrett TD, Shankley N, Breitenbucher JG. Pyrazole CCK(1) receptor antagonists. Part 1: Solution-phase library synthesis and determination of Free-Wilson additivity. Bioorg Med Chem Lett 2005; 16:72-6. [PMID: 16236513 DOI: 10.1016/j.bmcl.2005.09.048] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2005] [Revised: 09/09/2005] [Accepted: 09/20/2005] [Indexed: 11/21/2022]
Abstract
High throughput screening revealed compound 1 as a potent antagonist of the CCK(1) receptor. Evaluation of the CCK(1) SAR in a series of these diarylpyrazole antagonists was conducted in a matrix synthesis format revealing additive (Free-Wilson) and non-additive SAR. This use of additive QSAR modeling in conjunction with combinatorial libraries represents a unique approach to the evaluation of SAR interactions between the variables of any combinatorial matrix.
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Affiliation(s)
- Kelly McClure
- Johnson and Johnson Pharmaceutical Research and Development L.L.C., 3210 Merryfield Row, San Diego, CA 92121, USA
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Affiliation(s)
- Francesca Fanelli
- Dulbecco Telethon Institute and Department of Chemistry, University of Modena and Reggio Emilia, via Campi 183, 41100 Modena, Italy.
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Martín-Martínez M, Marty A, Jourdan M, Escrieut C, Archer E, González-Muñiz R, García-López MT, Maigret B, Herranz R, Fourmy D. Combination of molecular modeling, site-directed mutagenesis, and SAR studies to delineate the binding site of pyridopyrimidine antagonists on the human CCK1 receptor. J Med Chem 2005; 48:4842-50. [PMID: 16033264 DOI: 10.1021/jm0501127] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A rational combination of site-directed mutagenesis studies, structure-activity relationships, and dynamic-based docking of pyridopyrimidine-derived CCK1R antagonists into a refined three-dimensional model of the CCK1R allowed us to identify the receptor residues and the ligand functional groups implicated in the molecular recognition process. Our results provided unambiguous evidence that the binding site of these antagonists is overlapping that of the C-terminal tetrapeptide of CCK. In particular, Asn333 and Arg336 residues of the CCK1R are essential for high-affinity binding of these ligands. Moreover, the 2-aryl group in the pyridopyrimidine derivatives shares the same binding pocket as the C-terminal Phe side chain of CCK. Our [pyridopyrimidine.CCK1R] complex model is consistent with previous suggestions concerning the molecular basis that governs functional activity and provides useful considerations about the high CCK1 versus CCK2 selectivity of our derivatives and could contribute to fine-tune the rational design of new molecules with optimized properties.
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Archer-Lahlou E, Escrieut C, Clerc P, Martinez J, Moroder L, Logsdon C, Kopin A, Seva C, Dufresne M, Pradayrol L, Maigret B, Fourmy D. Molecular mechanism underlying partial and full agonism mediated by the human cholecystokinin-1 receptor. J Biol Chem 2005; 280:10664-74. [PMID: 15632187 DOI: 10.1074/jbc.m409451200] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The cholecystokinin-1 receptor (CCK1R) is a G protein-coupled receptor (GPCR) that regulates important physiological functions. As for other GPCRs, the molecular basis of full and partial agonism is still far from clearly understood. In the present report, using both laboratory experiments and molecular modeling approaches, we have investigated the partial agonism mechanism of JMV 180, on the human CCK1R. We first showed that efficacy of the CCK1R to activate phospholipase C is dependent on the correct orientation of the C-terminal end of peptidic ligands toward residue Phe(330) of helix VI. We have previously reported that a single mutation of Met(121) (helix III) markedly reduced the receptor-mediated inositol phosphate production upon stimulation by CCK. Computational simulations predicted that residue 121 affected orientation of the C-terminal end of CCK, thus suggesting that the molecular complex with a reduced inositol phosphate production observed with the mutated CCK1R resembles that resulting from binding of JMV 180 to the WT-CCK1R. Pharmacological, biochemical, and functional characterizations of the two receptor.ligand complexes with decreased abilities to signal were carried out in different cell types. We found that they presented the same features, such as total dependence of inositol phosphate production to Galpha(q) expression, single affinity of binding sites, insensitivity of binding to non-hydrolyzable GTP, absence of GTPgamma[S(35)] binding following agonist stimulation, similarity of dose-response curves for amylase secretion, and incapacity to induce acute pancreatitis in pancreatic acini. We concluded that helices VI and III of the CCK1R are functionally linked through the CCK1R agonist binding site and that positioning of the C-terminal ends of peptidic agonists toward Phe(330) of helix VI is responsible for extent of phospholipase C activation through Galpha(q) coupling. Given the potential therapeutic interest of partial agonists such as JMV 180, our structural data will serve for target structure-based design of new CCK1R ligands.
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Affiliation(s)
- Elodie Archer-Lahlou
- INSERM U 531, Centre Hospitalier Universitaire Rangueil, Bat. L3, TSA 50032, 31059 Toulouse cedex 9, France
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