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Richard T, Petit E, Pouységu L, Monti JP, Bondon A, Sylla T, Mérillon JM, Quideau S, Da Costa G. Impact of polyphenols on receptor-ligand interactions by NMR: the case of neurotensin (NT)-neurotensin receptor fragment (NTS1) complex. J Biomol Struct Dyn 2019; 38:1467-1478. [PMID: 31046599 DOI: 10.1080/07391102.2019.1608863] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Ligand-receptor interactions can be implicated in many pathological events such as chronic neurodegenerative diseases. Thus, the discovery of molecules disrupting this type of interactions could be an interesting therapeutic approach. Polyphenols are well known for their affinity for proteins and several studies have characterized these direct interactions. But studying the direct influence of multi-therapeutic drugs on a ligand-receptor complex relevant to a neurodegenerative disorder is a challenging issue. Solution NMR, molecular modeling and iterative calculations were used to obtain information about the interaction between a phenolic compound, α-glucogallin (α-2) and a ligand/fragment receptor complex neurotensin (NT) and its receptor NTS1. The α-2 was shown to bind to NT and a peptidic fragment of its NTS1 receptor, independently. Although the formation of the corresponding ligand-receptor complex did not seem to be affected, this experimental modeling protocol will enable the evaluation of other anti-amyloidogenic compounds such as blockers of NT-NTS1 binding. These types of studies help in understanding the specificity and influence in binding and can provide information to develop new molecules with a putative pharmacological interest.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Tristan Richard
- Université de Bordeaux, ISVV, EA 4577, USC 1366 INRA, Unité de Recherche OEnologie, Villenave d'Ornon, France
| | - Eva Petit
- Université de Toulouse, Institut National Polytechnique de Toulouse, Ecole d'Ingénieurs de Purpan, Unité Propre Physiologie, Pathologie et Génétique Végétales (PPGV), Toulouse, France
| | | | - Jean-Pierre Monti
- Université de Bordeaux, Laboratoire de Physique et Biophysique, Bordeaux, France
| | - Arnaud Bondon
- Université de Rennes, CNRS, ISCR - UMR 6226, Rennes, France
| | - Tahiri Sylla
- Université de Bordeaux, ISM (CNRS-UMR 5255), Talence, France
| | - Jean-Michel Mérillon
- Université de Bordeaux, ISVV, EA 4577, USC 1366 INRA, Unité de Recherche OEnologie, Villenave d'Ornon, France
| | | | - Grégory Da Costa
- Université de Bordeaux, ISVV, EA 4577, USC 1366 INRA, Unité de Recherche OEnologie, Villenave d'Ornon, France
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2
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Yang Y, Harmon CM. Molecular signatures of human melanocortin receptors for ligand binding and signaling. Biochim Biophys Acta Mol Basis Dis 2017; 1863:2436-2447. [PMID: 28478228 DOI: 10.1016/j.bbadis.2017.04.025] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2016] [Revised: 04/10/2017] [Accepted: 04/29/2017] [Indexed: 12/29/2022]
Abstract
Human melanocortin receptors (hMCRs) belong to the seven-transmembrane (TM) domain proteins. There are five hMCR subtypes and each of these receptor subtypes has different patterns of tissue expression and physiological function. The endogenous agonists for hMCRs are α-, β-, and γ-MSH and ACTH and endogenous antagonists are Agouti and AGRP which are the only known naturally occurring antagonists for the receptors. These peptides have their own profiles regarding the relative potency for specific hMCR subtype. Extensive studies have been performed to examine the molecular basis of the hMCRs for different ligand binding affinity and potency. Studies indicate that natural ligand α-MSH utilizes conserved amino acid residues for MCR specific binding (orthosteric binding) while synthetic ligands utilize non-conserved amino acid residues for receptor subtype specific binding (allosteric binding). ACTH is the only endogenous agonist for hMC2R and more amino acid residues at hMC2R are required for ACTH binding and signaling. HMCR computer modeling provides the detailed information of ligand and MCR interaction. This review provides the latest understanding of the molecular basis of the hMCRs for ligand binding and signaling. This article is part of a Special Issue entitled: Melanocortin Receptors - edited by Ya-Xiong Tao.
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Affiliation(s)
- Yingkui Yang
- Department of Surgery, State University of New York at Buffalo, Buffalo, NY 14203, United States.
| | - Carroll M Harmon
- Department of Surgery, State University of New York at Buffalo, Buffalo, NY 14203, United States
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3
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Ganjiwale A, Cowsik SM. Membrane-induced structure of novel human tachykinin hemokinin-1 (hHK1). Biopolymers 2015; 103:702-10. [DOI: 10.1002/bip.22734] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2015] [Revised: 08/06/2015] [Accepted: 08/19/2015] [Indexed: 01/25/2023]
Affiliation(s)
- Anjali Ganjiwale
- Institute of Bioinformatics and Applied Biotechnology, Electronic City-Phase I; Bangalore Karanataka India
| | - Sudha M. Cowsik
- School of Life Sciences; Jawaharlal Nehru Univeristy; New Delhi, India
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Da Costa G, Bondon A, Coutant J, Curmi P, Monti JP. Intermolecular interactions between the neurotensin and the third extracellular loop of human neurotensin 1 receptor. J Biomol Struct Dyn 2013; 31:1381-92. [DOI: 10.1080/07391102.2012.736776] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Parrill AL. Computational Design and Experimental Characterization of GPCR Segment Models. Methods Enzymol 2013; 522:81-95. [DOI: 10.1016/b978-0-12-407865-9.00005-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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6
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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] [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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7
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Ganjiwale AD, Rao GS, Cowsik SM. Molecular Modeling of Neurokinin B and Tachykinin NK3 Receptor Complex. J Chem Inf Model 2011; 51:2932-8. [DOI: 10.1021/ci2000264] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Affiliation(s)
- Anjali D. Ganjiwale
- School of Life Sciences, Jawaharlal Nehru University, New Delhi − 110 067, India
| | - Gita Subba Rao
- Department of Biophysics, All India Institute of Medical Sciences, New Delhi, India
| | - Sudha M. Cowsik
- School of Life Sciences, Jawaharlal Nehru University, New Delhi − 110 067, India
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8
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Langelaan DN, Ngweniform P, Rainey JK. Biophysical characterization of G-protein coupled receptor-peptide ligand binding. Biochem Cell Biol 2011; 89:98-105. [PMID: 21455262 DOI: 10.1139/o10-142] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
G-protein coupled receptors (GPCRs) are ubiquitous membrane proteins allowing intracellular responses to extracellular factors that range from photons of light to small molecules to proteins. Despite extensive exploitation of GPCRs as therapeutic targets, biophysical characterization of GPCR-ligand interactions remains challenging. In this minireview, we focus on techniques that have been successfully used for structural and biophysical characterization of peptide ligands binding to their cognate GPCRs. The techniques reviewed include solution-state nuclear magnetic resonance (NMR) spectroscopy, solid-state NMR, X-ray diffraction, fluorescence spectroscopy and single-molecule fluorescence methods, flow cytometry, surface plasmon resonance, isothermal titration calorimetry, and atomic force microscopy. The goal herein is to provide a cohesive starting point to allow selection of techniques appropriate to the elucidation of a given GPCR-peptide interaction.
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Affiliation(s)
- David N Langelaan
- Department of Biochemistry & Molecular Biology, Dalhousie University, 5850 College Street, Halifax, Nova Scotia, Canada
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9
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Grace CRR, Cowsik SM. Solution conformation of non-mammalian tachykinin physalaemin in lipid micelles by nuclear magnetic resonance. Biopolymers 2011; 96:252-9. [DOI: 10.1002/bip.21519] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Abstract
G protein-coupled receptors (GPCRs) comprise a large class of transmembrane proteins that play critical roles in both normal physiology and pathophysiology. These critical roles offer targets for therapeutic intervention, as exemplified by the substantial fraction of current pharmaceutical agents that target members of this family. Tremendous contributions to our understanding of GPCR structure and dynamics have come from both indirect and direct structural characterization techniques. Key features of GPCR conformations derived from both types of characterization techniques are reviewed.
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Affiliation(s)
- Abby L. Parrill
- Department of Chemistry, The University of Memphis, Memphis, TN 38152, USA
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +1-901-678-2638; Fax: +1-901-678-3447
| | - Debra L. Bautista
- Christian Brothers High School, 5900 Walnut Grove Road, Memphis, TN 38120, USA; E-Mail: (D.L.B.)
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11
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Fornelli L, Schmid AW, Grasso L, Vogel H, Tsybin YO. Deamidation and transamidation of substance P by tissue transglutaminase revealed by electron-capture dissociation fourier transform mass spectrometry. Chemistry 2010; 17:486-97. [PMID: 21207565 DOI: 10.1002/chem.201002483] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2010] [Indexed: 11/07/2022]
Abstract
Tissue transglutaminase (tTGase) catalyzes both deamidation and transamidation of peptides and proteins by using a peptidyl glutamine as primary substrate. A precise consensus sequence for the enzyme is unknown and the ratio between deamidated and transamidated (or cross-linked) reaction products is highly substrate-dependent. Due to its overlapping body distribution with tTGase and ease of manipulation with tandem mass spectrometry, we used the neuropeptide substance P as a model to investigate the associated enzymatic kinetics and reaction products. Online liquid-chromatography Fourier-transform ion-cyclotron-resonance mass spectrometry (FT-ICR MS) combined with electron-capture dissociation (ECD) was employed to study the tTGase-induced modifications of substance P. A particular strength of ECD for peptide-enzyme reaction product monitoring is its ability to distinguish isomeric amino acids, for example, Glu and iso-Glu, by signature product ions. Our studies show that the primary reaction observed is deamidation, with the two consecutive glutamine residues converted sequentially into glutamate: first Gln(5) , and subsequently Gln(6) . We then applied ECD FT-ICR MS to identify the transamidation site on an enzymatically cross-linked peptide, which turned out to correspond to Gln(5) . Three populations of substance-P dimers were detected that differed by the number of deamidated Gln residues. The higher reactivity of Gln(5) over Gln(6) was further confirmed by cross-linking SP with monodansylcadaverine (MDC). Overall, our approach described herein is of a general importance for mapping both enzymatically induced post-translational protein modifications and cross-linking. Finally, in vitro Ca-signaling assays revealed that the main tTGase reaction product, the singly deamidated SP (RPKPEQFFGLM-NH(2) ), has increased agonist potency towards its natural receptor, thus confirming the biologically relevant role of deamidation.
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Affiliation(s)
- Luca Fornelli
- Biomolecular Mass Spectrometry Laboratory, Ecole Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland
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12
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Tikhonova IG, Costanzi S. Unraveling the structure and function of G protein-coupled receptors through NMR spectroscopy. Curr Pharm Des 2010; 15:4003-16. [PMID: 20028318 DOI: 10.2174/138161209789824803] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
G protein-coupled receptors (GPCRs) are a large superfamily of signaling proteins expressed on the plasma membrane. They are involved in a wide range of physiological processes and, therefore, are exploited as drug targets in a multitude of therapeutic areas. In this extent, knowledge of structural and functional properties of GPCRs may greatly facilitate rational design of modulator compounds. Solution and solid-state nuclear magnetic resonance (NMR) spectroscopy represents a powerful method to gather atomistic insights into protein structure and dynamics. In spite of the difficulties inherent the solution of the structure of membrane proteins through NMR, these methods have been successfully applied, sometimes in combination with molecular modeling, to the determination of the structure of GPCR fragments, the mapping of receptor-ligand interactions, and the study of the conformational changes associated with the activation of the receptors. In this review, we provide a summary of the NMR contributions to the study of the structure and function of GPCRs, also in light of the published crystal structures.
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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, DHHS, Bethesda, MD 20892, USA
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13
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Yeagle PL, Albert AD. Membrane protein fragments reveal both secondary and tertiary structure of membrane proteins. Methods Mol Biol 2010; 654:283-301. [PMID: 20665272 DOI: 10.1007/978-1-60761-762-4_15] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Structural data on membrane proteins, while crucial to understanding cellular function, are scarce due to difficulties in applying to membrane proteins the common techniques of structural biology. Fragments of membrane proteins have been shown to reflect, in many cases, the secondary structure of the parent protein with fidelity and are more amenable to study. This chapter provides many examples of how the study of membrane protein fragments has provided new insight into the structure of the parent membrane protein.
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Affiliation(s)
- Philip L Yeagle
- Office of the Dean of Arts & Sciences, Rutgers University, Newark, NJ, USA.
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14
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Chandrashekaran IR, Rao GS, Cowsik SM. Molecular modeling of the peptide agonist-binding site in a neurokinin-2 receptor. J Chem Inf Model 2009; 49:1734-40. [PMID: 19534508 DOI: 10.1021/ci900055x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The neurokinin-2 receptor is a member of the rhodopsin family of G-protein coupled receptors, which represents one of the most relevant target families in small-molecule drug design. NK-2 receptors have been implicated in playing a pathophysiological role in asthma. Activation of the NK-2 receptor by its endogenous peptide agonist, tachykinins, is associated with diverse biological responses like bronchoconstriction, vasodepression, and regulation of endocrine functions. Agonist binding to the receptor is a crucial event in initiating signaling, and therefore characterization of the structural features of the agonists can reveal the molecular basis of receptor activation and help in rational design of novel therapeutics. In this study a molecular model for the interaction of the primary ligand NKA with its G-protein coupled receptor neurokinin-2 receptor has been developed. A three-dimensional model for the NK-2 receptor has been generated by homology modeling using rhodopsin as a template. A knowledge based docking of the NMR derived bioactive conformation of NKA to the receptor has been performed utilizing the ligand binding data obtained from the photoaffinity labeling and site-directed mutagenesis studies. The molecular model for the NKA/NK-2 receptor complex thus obtained sheds light on the topographical features of the binding pocket of the receptor and provides atomic insight into the biochemical data currently available for the receptor. The results of the receptor modeling studies have been used to discuss the molecular determinants for NK-2 receptor selectivity.
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15
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Zou C, Kumaran S, Markovic S, Walser R, Zerbe O. Studies of the structure of the N-terminal domain from the Y4 receptor - a G protein-coupled receptor - and its interaction with hormones from the NPY family. Chembiochem 2009; 9:2276-84. [PMID: 18767100 DOI: 10.1002/cbic.200800221] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Binding of peptide hormones to G protein-coupled receptors is believed to be mediated through formation of contacts of the ligands with residues of the extracellular loops of family 1 GPCRs. Here we have investigated whether additional binding sites exist within the N-terminal domain, as studied in the form of binding of peptides from the neuropeptide Y (NPY) family to the N terminus of the Y4 receptor (N-Y4). The N-terminal domain of the Y4 receptor has been expressed in isotopically enriched form and studied by solution NMR spectroscopy. The peptide is unstructured in solution, whereas a micelle-associated helical segment is formed in the presence of dodecylphosphocholine (DPC) or sodium dodecylsulfate (SDS). As measured by surface plasmon resonance (SPR) spectroscopy, N-Y4 binds with approximately 50 microM affinity to the pancreatic polypeptide (PP), a high-affinity ligand to the Y4 receptor, whereas binding to neuropeptide Y (NPY) and peptide YY (PYY) is much weaker. Residues critical for binding in PP and in N-Y4 have been identified by site-directed mutagenesis. The data indicate that electrostatic interactions dominate and that this interaction is mediated by acidic ligand and basic receptor residues. Residues of N-Y4 are likely to contribute to the binding of PP, and in addition might possibly also help to transfer the hormone from the membrane-bound state into the receptor binding pocket.
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Affiliation(s)
- Chao Zou
- Institute of Organic Chemistry, University of Zürich, Switzerland
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16
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Vincent B, Mouledous L, Bes B, Mazarguil H, Meunier JC, Milon A, Demange P. Description of the low-affinity interaction between nociceptin and the second extracellular loop of its receptor by fluorescence and NMR spectroscopies. J Pept Sci 2008; 14:1183-94. [PMID: 18683278 DOI: 10.1002/psc.1057] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2008] [Accepted: 05/26/2008] [Indexed: 12/16/2023]
Abstract
The second extracellular loop (ECL2) of the Noc receptor has been proposed to be involved in ligand binding and selectivity. The interaction of Noc with a constrained cyclic synthetic peptide, mimicking the ECL2, has been studied using fluorescence and NMR spectroscopies. Selective binding was shown with a dissociation constant of approximately 10 microM (observed with the constrained cyclic loop and not with the open chain), and residues involved in ligand binding and selectivity have been identified. This bimolecular complex is stabilized by (i) ionic interactions between the two Noc basic motives and the ECL2 acidic residues; (ii) hydrophobic contacts involving Noc FGGF N-terminal sequence and an ECL2 tryptophane residue. Our data confirm that Noc receptor's ECL2 contributes actively to ligand binding and selectivity by providing the peptidic ligand with a low affinity-binding site.
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Affiliation(s)
- Bruno Vincent
- Université de Toulouse, Institute of Pharmacology and Structural Biology, IPBS, UPS, 31077, Toulouse, France
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17
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The role of the N-terminal and mid-region residues of substance P in regulating functional selectivity at the tachykinin NK1 receptor. Eur J Pharmacol 2008; 592:1-6. [DOI: 10.1016/j.ejphar.2008.06.097] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2008] [Revised: 06/18/2008] [Accepted: 06/22/2008] [Indexed: 11/17/2022]
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18
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Boivin S, Ségalas-Milazzo I, Guilhaudis L, Oulyadi H, Fournier A, Davoust D. Solution structure of urotensin-II receptor extracellular loop III and characterization of its interaction with urotensin-II. Peptides 2008; 29:700-10. [PMID: 18423797 DOI: 10.1016/j.peptides.2008.02.024] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/29/2007] [Revised: 02/28/2008] [Accepted: 02/29/2008] [Indexed: 11/15/2022]
Abstract
Urotensin-II (U-II) is a vasoactive hormone that acts through a G-protein-coupled receptor named UT. Recently, we have shown, using the surface plasmon resonance technology that human U-II (hU-II) interacts with the hUT(281-300) fragment, a segment containing the extracellular loop III (EC-III) and short extensions of the transmembrane domains VI and VII (TM-VI and TM-VII). To further investigate the interaction of UT receptor with U-II, we have determined the solution structure of hUT(281-300) by high-resolution NMR and molecular modeling and we have examined, also using NMR, the binding with hU-II at residue level. In the presence of dodecylphosphocholine micelles, hUT(281-300) exhibited a type III beta-turn (Q285-L288), followed by an -helical structure (A289-L299), the latter including a stretch of transmembrane helix VII. Upon addition of hU-II, significant chemical shift perturbations were observed for residues located just on the N-terminal side of the beta-turn (end of TM-VI/beginning of EC-III) and on one face of the -helix (end of EC-III/beginning of TM-VII). These data, in conjunction with intermolecular NOEs, suggest that the initiation site of EC-III, as well as the upstream portion of helix VII, would be involved in agonist binding and allow to propose points of interaction in the ligand-receptor complex.
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Affiliation(s)
- Stéphane Boivin
- Equipe de Chimie Organique et de Biologie Structurale, Université de Rouen, 1 rue Thomas Becket, 76821 Mont-Saint-Aignan, France
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Mierke DF, Mao L, Pellegrini M, Piserchio A, Plati J, Tsomaia N. Structural characterization of the parathyroid hormone receptor domains determinant for ligand binding. Biochem Soc Trans 2007; 35:721-3. [PMID: 17635133 DOI: 10.1042/bst0350721] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Over the years, the association of peptide ligands to Family B GPCRs (G-protein coupled receptors) has been characterized by a number of experimental and theoretical techniques. For the PTH (parathyroid hormone) ligand-receptor system, important insight has been provided by photoaffinity labelling experiments and the elucidation of direct contact points between ligand and receptor. Our research has focused on the structural elucidation of the receptor domains shown to be involved in the binding of PTH. Employing a combination of carefully designed receptor domains, solution-state NMR carried out in the presence of membrane mimetics and extensive computer simulations, we have obtained a well-resolved model of the ligand-receptor complex for PTH. Here, we review the development of this model and highlight some inherent limitations of the methods employed and their consequences on interpretation of the ligand-receptor model.
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Affiliation(s)
- D F Mierke
- Department of Molecular Pharmacology, Division of Biology and Medicine, Brown University, Providence, RI 02912, USA.
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Yeagle PL, Albert AD. G-protein coupled receptor structure. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2006; 1768:808-24. [PMID: 17097603 DOI: 10.1016/j.bbamem.2006.10.002] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2006] [Revised: 10/02/2006] [Accepted: 10/05/2006] [Indexed: 11/18/2022]
Abstract
Because of their central role in regulation of cellular function, structure/function relationships for G-protein coupled receptors (GPCR) are of vital importance, yet only recently have sufficient data been obtained to begin mapping those relationships. GPCRs regulate a wide range of cellular processes, including the senses of taste, smell, and vision, and control a myriad of intracellular signaling systems in response to external stimuli. Many diseases are linked to GPCRs. A critical need exists for structural information to inform studies on mechanism of receptor action and regulation. X-ray crystal structures of only one GPCR, in an inactive state, have been obtained to date. However considerable structural information for a variety of GPCRs has been obtained using non-crystallographic approaches. This review begins with a review of the very earliest GPCR structural information, mostly derived from rhodopsin. Because of the difficulty in crystallizing GPCRs for X-ray crystallography, the extensive published work utilizing alternative approaches to GPCR structure is reviewed, including determination of three-dimensional structure from sparse constraints. The available X-ray crystallographic analyses on bovine rhodopsin are reviewed as the only available high-resolution structures for any GPCR. Structural information available on ligand binding to several receptors is included. The limited information on excited states of receptors is also reviewed. It is concluded that while considerable basic structural information has been obtained, more data are needed to describe the molecular mechanism of activation of a GPCR.
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Affiliation(s)
- Philip L Yeagle
- Department of Molecular and Cell Biology, University of Connecticut, Storrs, CT 06269, USA.
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21
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Fanelli F, De Benedetti PG. Computational Modeling Approaches to Structure−Function Analysis of G Protein-Coupled Receptors. Chem Rev 2005; 105:3297-351. [PMID: 16159154 DOI: 10.1021/cr000095n] [Citation(s) in RCA: 129] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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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