1
|
Phạm TTT, Murza A, Marsault É, Frampton JP, Rainey JK. Localized apelin-17 analogue-bicelle interactions as a facilitator of membrane-catalyzed receptor recognition and binding. BIOCHIMICA ET BIOPHYSICA ACTA. BIOMEMBRANES 2024; 1866:184289. [PMID: 38278504 DOI: 10.1016/j.bbamem.2024.184289] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2023] [Revised: 01/17/2024] [Accepted: 01/18/2024] [Indexed: 01/28/2024]
Abstract
The apelinergic system encompasses two peptide ligand families, apelin and apela, along with the apelin receptor (AR or APJ), a class A G-protein-coupled receptor. This system has diverse physiological effects, including modulating heart contraction, vasodilation/constriction, glucose regulation, and vascular development, with involvement in a variety of pathological conditions. Apelin peptides have been previously shown to interact with and become structured upon binding to anionic micelles, consistent with a membrane-catalyzed mechanism of ligand-receptor binding. To overcome the challenges of observing nuclear magnetic resonance (NMR) spectroscopy signals of a dilute peptide in biological environments, 19F NMR spectroscopy, including diffusion ordered spectroscopy (DOSY) and saturation transfer difference (STD) experiments, was used herein to explore the membrane-interactive behaviour of apelin. NMR-optimized apelin-17 analogues with 4-trifluoromethyl-phenylalanine at various positions were designed and tested for bioactivity through ERK activation in stably-AR transfected HEK 293 T cells. Far-UV circular dichroism (CD) spectropolarimetry and 19F NMR spectroscopy were used to compare the membrane interactions of these analogues with unlabelled apelin-17 in both zwitterionic/neutral and net-negative bicelle conditions. Each analogue binds to bicelles with relatively weak affinity (i.e., in fast exchange on the NMR timescale), with preferential interactions observed at the cationic residue-rich N-terminal and mid-length regions of the peptide leaving the C-terminal end unencumbered for receptor recognition, enabling a membrane-anchored fly-casting mechanism of peptide search for the receptor. In all, this study provides further insight into the membrane-interactive behaviour of an important bioactive peptide, demonstrating interactions and biophysical behaviour that cannot be neglected in therapeutic design.
Collapse
Affiliation(s)
- Trần Thanh Tâm Phạm
- Department of Biochemistry & Molecular Biology, Dalhousie University, Halifax, NS B3H 4R2, Canada
| | - Alexandre Murza
- Department of Pharmacology and Physiology, Faculty of Medicine and Health Sciences, Institut de Pharmacologie de Sherbrooke, Université de Sherbrooke, Sherbrooke, QC J1H 5N4, Canada
| | - Éric Marsault
- Department of Pharmacology and Physiology, Faculty of Medicine and Health Sciences, Institut de Pharmacologie de Sherbrooke, Université de Sherbrooke, Sherbrooke, QC J1H 5N4, Canada
| | - John P Frampton
- Department of Biochemistry & Molecular Biology, Dalhousie University, Halifax, NS B3H 4R2, Canada; School of Biomedical Engineering, Dalhousie University, Halifax, NS B3H 4R2, Canada
| | - Jan K Rainey
- Department of Biochemistry & Molecular Biology, Dalhousie University, Halifax, NS B3H 4R2, Canada; School of Biomedical Engineering, Dalhousie University, Halifax, NS B3H 4R2, Canada; Department of Chemistry, Dalhousie University, Halifax, NS B3H 4R2, Canada.
| |
Collapse
|
2
|
Desai D, Shende P. Dual-action of colloidal ISCOMs: an optimized approach using Box-Behnken design for the management of breast cancer. Biomed Microdevices 2022; 24:28. [DOI: 10.1007/s10544-022-00625-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/16/2022] [Indexed: 12/09/2022]
|
3
|
Greene ES, Abdelli N, Dridi JS, Dridi S. Avian Neuropeptide Y: Beyond Feed Intake Regulation. Vet Sci 2022; 9:171. [PMID: 35448669 PMCID: PMC9028514 DOI: 10.3390/vetsci9040171] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2022] [Revised: 03/28/2022] [Accepted: 03/29/2022] [Indexed: 11/16/2022] Open
Abstract
Neuropeptide Y (NPY) is one of the most abundant and ubiquitously expressed neuropeptides in both the central and peripheral nervous systems, and its regulatory effects on feed intake and appetite- have been extensively studied in a wide variety of animals, including mammalian and non-mammalian species. Indeed, NPY has been shown to be involved in the regulation of feed intake and energy homeostasis by exerting stimulatory effects on appetite and feeding behavior in several species including chickens, rabbits, rats and mouse. More recent studies have shown that this neuropeptide and its receptors are expressed in various peripheral tissues, including the thyroid, heart, spleen, adrenal glands, white adipose tissue, muscle and bone. Although well researched centrally, studies investigating the distribution and function of peripherally expressed NPY in avian (non-mammalian vertebrates) species are very limited. Thus, peripherally expressed NPY merits more consideration and further in-depth exploration to fully elucidate its functions, especially in non-mammalian species. The aim of the current review is to provide an integrated synopsis of both centrally and peripherally expressed NPY, with a special focus on the distribution and function of the latter.
Collapse
Affiliation(s)
- Elizabeth S. Greene
- Department of Poultry Science, University of Arkansas, Fayetteville, AR 72701, USA; (E.S.G.); (N.A.)
| | - Nedra Abdelli
- Department of Poultry Science, University of Arkansas, Fayetteville, AR 72701, USA; (E.S.G.); (N.A.)
- Animal Nutrition and Welfare Service, Department of Animal and Food Sciences, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain
| | - Jalila S. Dridi
- École Universitaire de Kinésithérapie, Université d’Orléans, Rue de Chartres, 45100 Orleans, France;
| | - Sami Dridi
- Department of Poultry Science, University of Arkansas, Fayetteville, AR 72701, USA; (E.S.G.); (N.A.)
| |
Collapse
|
4
|
Mintah Churcher NK, Upasham S, Rice P, Bhadsavle S, Prasad S. Development of a flexible, sweat-based neuropeptide Y detection platform. RSC Adv 2020; 10:23173-23186. [PMID: 35520310 PMCID: PMC9054693 DOI: 10.1039/d0ra03729j] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2020] [Accepted: 06/05/2020] [Indexed: 12/14/2022] Open
Abstract
Neuropeptide Y (NPY) biomarker levels have a close association with the diagnosis of Major Depression Disorder (MDD) and anxiety disorders. Quantifying NPY in correlation to self-reported symptoms will be an important measure to ensure a relatively uniform diagnosis and help with disease prognosis of these disorders. The work presented is a novel, passive eccrine sweat based, electrochemical detection platform for quantification of NPY biomarker levels. The paper offers a comparison between non-porous and porous sensor platforms using various electrochemical detection techniques. This work uses a novel strategy towards designing an optimal nanobioelectronic interface to measure NPY. The portability aspect of this detection platform is discussed by the demonstration a novel, portable EmStat Pico based electronic platform. The detection limit of the sensor is 10 pg mL−1 and its range is 20–500 pg mL−1. The NPY detection platform is envisioned to be a wearable point-of need monitoring system for management of chronic anxiety disorders and MDD. Novel wearable NPY biomarker tracking system, envisioned to be a chronic anxiety and MDD management platform via self-monitoring.![]()
Collapse
Affiliation(s)
| | - Sayali Upasham
- Department of Bioengineering
- University of Texas at Dallas
- Richardson
- USA
| | - Paul Rice
- Department of Bioengineering
- University of Texas at Dallas
- Richardson
- USA
| | - Serena Bhadsavle
- Department of Bioengineering
- University of Texas at Dallas
- Richardson
- USA
| | - Shalini Prasad
- Department of Bioengineering
- University of Texas at Dallas
- Richardson
- USA
| |
Collapse
|
5
|
Hall L, Donovan E, Araya M, Idowa E, Jiminez-Segovia I, Folck A, Wells CD, Kimble-Hill AC. Identification of Specific Lysines and Arginines That Mediate Angiomotin Membrane Association. ACS OMEGA 2019; 4:6726-6736. [PMID: 31179409 PMCID: PMC6547806 DOI: 10.1021/acsomega.9b00165] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2019] [Accepted: 03/28/2019] [Indexed: 05/17/2023]
Abstract
The family of Angiomotin (Amot) proteins regulate several biological pathways associated with cellular differentiation, proliferation, and migration. These adaptor proteins target proteins to the apical membrane, actin fibers, or the nucleus. A major function of the Amot coiled-coil homology (ACCH) domain is to initiate protein interactions with the cellular membrane, particularly those containing phosphatidylinositol lipids. The work presented in this article uses several ACCH domain lysine/arginine mutants to probe the relative importance of individual residues for lipid binding. This identified four lysine and three arginine residues that mediate full lipid binding. Based on these findings, three of these residues were mutated to glutamates in the Angiomotin 80 kDa splice form and were incorporated into human mammary cell lines. Results show that mutating three of these residues in the context of full-length Angiomotin reduced the residence of the protein at the apical membrane. These findings provide new insight into how the ACCH domain mediates lipid binding to enable Amot proteins to control epithelial cell growth.
Collapse
Affiliation(s)
- Le’Celia Hall
- Department of Biochemistry
and Molecular Biology, Indiana University
School of Medicine, Room MS 4053, 635 Barnhill Drive, Indianapolis, Indiana 46202, United
States
| | - Emily Donovan
- Department of Biochemistry
and Molecular Biology, Indiana University
School of Medicine, Room MS 4053, 635 Barnhill Drive, Indianapolis, Indiana 46202, United
States
| | - Michael Araya
- Department of Biochemistry
and Molecular Biology, Indiana University
School of Medicine, Room MS 4053, 635 Barnhill Drive, Indianapolis, Indiana 46202, United
States
| | - Eniola Idowa
- Department of Biochemistry
and Molecular Biology, Indiana University
School of Medicine, Room MS 4053, 635 Barnhill Drive, Indianapolis, Indiana 46202, United
States
| | - Ilse Jiminez-Segovia
- Department of Biochemistry
and Molecular Biology, Indiana University
School of Medicine, Room MS 4053, 635 Barnhill Drive, Indianapolis, Indiana 46202, United
States
| | - Anthony Folck
- Department of Biochemistry
and Molecular Biology, Indiana University
School of Medicine, Room MS 4053, 635 Barnhill Drive, Indianapolis, Indiana 46202, United
States
| | - Clark D. Wells
- Department of Biochemistry
and Molecular Biology, Indiana University
School of Medicine, Room MS 4053, 635 Barnhill Drive, Indianapolis, Indiana 46202, United
States
| | - Ann C. Kimble-Hill
- Department of Biochemistry
and Molecular Biology, Indiana University
School of Medicine, Room MS 4053, 635 Barnhill Drive, Indianapolis, Indiana 46202, United
States
| |
Collapse
|
6
|
Kögler LM, Stichel J, Kaiser A, Beck-Sickinger AG. Cell-Free Expression and Photo-Crosslinking of the Human Neuropeptide Y 2 Receptor. Front Pharmacol 2019; 10:176. [PMID: 30881304 PMCID: PMC6405639 DOI: 10.3389/fphar.2019.00176] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2018] [Accepted: 02/11/2019] [Indexed: 12/15/2022] Open
Abstract
G protein-coupled receptors (GPCRs) represent a large family of different proteins, which are involved in physiological processes throughout the entire body. Furthermore, they represent important drug targets. For rational drug design, it is important to get further insights into the binding mode of endogenous ligands as well as of therapeutic agents at the respective target receptors. However, structural investigations usually require homogenous, solubilized and functional receptors, which is still challenging. Cell-free expression methods have emerged in the last years and many different proteins are successfully expressed, including hydrophobic membrane proteins like GPCRs. In this work, an Escherichia coli based cell-free expression system was used to express the neuropeptide Y2 receptor (Y2R) for structural investigations. This GPCR was expressed in two different variants, a C-terminal enhanced green fluorescent fusion protein and a cysteine deficient variant. In order to obtain soluble receptors, the expression was performed in the presence of mild detergents, either Brij-35 or Brij-58, which led to high amounts of soluble receptor. Furthermore, the influence of temperature, pH value and additives on protein expression and solubilization was tested. For functional and structural investigations, the receptors were expressed at 37°C, pH 7.4 in the presence of 1 mM oxidized and 5 mM reduced glutathione. The expressed receptors were purified by ligand affinity chromatography and functionality of Y2R_cysteine_deficient was verified by a homogenous binding assay. Finally, photo-crosslinking studies were performed between cell-free expressed Y2R_cysteine_deficient and a neuropeptide Y (NPY) analog bearing the photoactive, unnatural amino acid p-benzoyl-phenylalanine at position 27 and biotin at position 22 for purification. After enzymatic digestion, fragments of crosslinked receptor were identified by mass spectrometry. Our findings demonstrate that, in contrast to Y1R, NPY position 27 remains flexible when bound to Y2R. These results are in agreement with the suggested binding mode of NPY at Y2R.
Collapse
Affiliation(s)
- Lisa Maria Kögler
- Institute of Biochemistry, Faculty of Life Sciences, Leipzig University, Leipzig, Germany
| | - Jan Stichel
- Institute of Biochemistry, Faculty of Life Sciences, Leipzig University, Leipzig, Germany
| | - Anette Kaiser
- Institute of Biochemistry, Faculty of Life Sciences, Leipzig University, Leipzig, Germany
| | | |
Collapse
|
7
|
Shen C, Xue M, Qiu H, Guo W. Insertion of Neurotransmitters into a Lipid Bilayer Membrane and Its Implication on Membrane Stability: A Molecular Dynamics Study. Chemphyschem 2017; 18:626-633. [PMID: 28054433 DOI: 10.1002/cphc.201601184] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2016] [Revised: 12/13/2016] [Indexed: 12/29/2022]
Abstract
The signaling molecules in neurons, called neurotransmitters, play an essential role in the transportation of neural signals, during which the neurotransmitters interact with not only specific receptors, but also cytomembranes, such as synaptic vesicle membranes and postsynaptic membranes. Through extensive molecular dynamics simulations, the atomic-scale insertion dynamics of typical neurotransmitters, including methionine enkephalin (ME), leucine enkephalin (LE), dopamine (DA), acetylcholine (ACh), and aspartic acid (ASP), into lipid bilayers is investigated. The results show that the first three neurotransmitters (ME, LE, and DA) are able to diffuse freely into both 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) and 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphoethanolamine (POPE) membranes, and are guided by the aromatic residues Tyr and Phe. Only a limited number of these neurotransmitters are allowed to penetrate into the membrane, which suggests an intrinsic mechanism by which the membrane is protected from being destroyed by excessive inserted neurotransmitters. After spontaneous insertion, the neurotransmitters disturb the surrounding phospholipids in the membrane, as indicated by the altered distribution of components in lipid leaflets and the disordered lipid tails. In contrast, the last two neurotransmitters (ACh and ASP) cannot enter the membrane, but instead always diffuse freely in solution. These findings provide an understanding at the atomic level of how neurotransmitters interact with the surrounding cytomembrane, as well as their impact on membrane behavior.
Collapse
Affiliation(s)
- Chun Shen
- State Key Laboratory of Mechanics and Control of Mechanical Structure and Key Laboratory for Intelligent Nano Materials and Devices of the, Ministry of Education, and Institute of Nanoscience, Nanjing University of Aeronautics and Astronautics, 29 Yudao Street, Nanjing, P.R. China
| | - Minmin Xue
- State Key Laboratory of Mechanics and Control of Mechanical Structure and Key Laboratory for Intelligent Nano Materials and Devices of the, Ministry of Education, and Institute of Nanoscience, Nanjing University of Aeronautics and Astronautics, 29 Yudao Street, Nanjing, P.R. China
| | - Hu Qiu
- State Key Laboratory of Mechanics and Control of Mechanical Structure and Key Laboratory for Intelligent Nano Materials and Devices of the, Ministry of Education, and Institute of Nanoscience, Nanjing University of Aeronautics and Astronautics, 29 Yudao Street, Nanjing, P.R. China
| | - Wanlin Guo
- State Key Laboratory of Mechanics and Control of Mechanical Structure and Key Laboratory for Intelligent Nano Materials and Devices of the, Ministry of Education, and Institute of Nanoscience, Nanjing University of Aeronautics and Astronautics, 29 Yudao Street, Nanjing, P.R. China
| |
Collapse
|
8
|
Huster D. Solid-state NMR spectroscopy to study protein-lipid interactions. Biochim Biophys Acta Mol Cell Biol Lipids 2013; 1841:1146-60. [PMID: 24333800 DOI: 10.1016/j.bbalip.2013.12.002] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2013] [Accepted: 12/04/2013] [Indexed: 12/22/2022]
Abstract
The appropriate lipid environment is crucial for the proper function of membrane proteins. There is a tremendous variety of lipid molecules in the membrane and so far it is often unclear which component of the lipid matrix is essential for the function of a respective protein. Lipid molecules and proteins mutually influence each other; parameters such as acyl chain order, membrane thickness, membrane elasticity, permeability, lipid-domain and annulus formation are strongly modulated by proteins. More recent data also indicates that the influence of proteins goes beyond a single annulus of next-neighbor boundary lipids. Therefore, a mesoscopic approach to membrane lipid-protein interactions in terms of elastic membrane deformations has been developed. Solid-state NMR has greatly contributed to the understanding of lipid-protein interactions and the modern view of biological membranes. Methods that detect the influence of proteins on the membrane as well as direct lipid-protein interactions have been developed and are reviewed here. Examples for solid-state NMR studies on the interaction of Ras proteins, the antimicrobial peptide protegrin-1, the G protein-coupled receptor rhodopsin, and the K(+) channel KcsA are discussed. This article is part of a Special Issue entitled Tools to study lipid functions.
Collapse
Affiliation(s)
- Daniel Huster
- Institute of Medical Physics and Biophysics, University of Leipzig, Härtelstr. 16-18, D-04107 Leipzig, Germany.
| |
Collapse
|
9
|
The spin label amino acid TOAC and its uses in studies of peptides: chemical, physicochemical, spectroscopic, and conformational aspects. Biophys Rev 2012; 4:45-66. [PMID: 22347893 PMCID: PMC3271205 DOI: 10.1007/s12551-011-0064-5] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2011] [Accepted: 12/20/2011] [Indexed: 01/21/2023] Open
Abstract
We review work on the paramagnetic amino acid 2,2,6,6-tetramethyl-N-oxyl-4-amino-4-carboxylic acid, TOAC, and its applications in studies of peptides and peptide synthesis. TOAC was the first spin label probe incorporated in peptides by means of a peptide bond. In view of the rigid character of this cyclic molecule and its attachment to the peptide backbone via a peptide bond, TOAC incorporation has been very useful to analyze backbone dynamics and peptide secondary structure. Many of these studies were performed making use of EPR spectroscopy, but other physical techniques, such as X-ray crystallography, CD, fluorescence, NMR, and FT-IR, have been employed. The use of double-labeled synthetic peptides has allowed the investigation of their secondary structure. A large number of studies have focused on the interaction of peptides, both synthetic and biologically active, with membranes. In the latter case, work has been reported on ligands and fragments of GPCR, host defense peptides, phospholamban, and β-amyloid. EPR studies of macroscopically aligned samples have provided information on the orientation of peptides in membranes. More recent studies have focused on peptide–protein and peptide–nucleic acid interactions. Moreover, TOAC has been shown to be a valuable probe for paramagnetic relaxation enhancement NMR studies of the interaction of labeled peptides with proteins. The growth of the number of TOAC-related publications suggests that this unnatural amino acid will find increasing applications in the future.
Collapse
|
10
|
Chu S, Maltsev S, Emwas AH, Lorigan GA. Solid-state NMR paramagnetic relaxation enhancement immersion depth studies in phospholipid bilayers. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2010; 207:89-94. [PMID: 20851650 PMCID: PMC2978330 DOI: 10.1016/j.jmr.2010.08.012] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2010] [Revised: 08/11/2010] [Accepted: 08/18/2010] [Indexed: 05/20/2023]
Abstract
A new approach for determining the membrane immersion depth of a spin-labeled probe has been developed using paramagnetic relaxation enhancement (PRE) in solid-state NMR spectroscopy. A DOXYL spin label was placed at different sites of 1-palmitoyl-2-stearoyl-sn-glycero-3-phosphocholine (PSPC) phospholipid bilayers as paramagnetic moieties and the resulting enhancements of the longitudinal relaxation (T₁) times of ³¹P nuclei on the surface of the bilayers were measured by a standard inversion recovery pulse sequence. The ³¹P NMR spin-lattice relaxation times decrease steadily as the DOXYL spin label moves closer to the surface as well as the concentration of the spin-labeled lipids increase. The enhanced relaxation vs. the position and concentration of spin-labels indicate that PRE induced by the DOXYL spin label are significant to determine longer distances over the whole range of the membrane depths. When these data were combined with estimated correlation times τ(c), the r⁻⁶-weighted, time-averaged distances between the spin-labels and the ³¹P nuclei on the membrane surface were estimated. The application of using this solid-state NMR PRE approach coupled with site-directed spin labeling (SDSL) may be a powerful method for measuring membrane protein immersion depth.
Collapse
Affiliation(s)
- Shidong Chu
- Department of Chemistry and Biochemistry, Miami University, Oxford, OH, USA 45056
| | - Sergey Maltsev
- Department of Chemistry and Biochemistry, Miami University, Oxford, OH, USA 45056
| | - A-H Emwas
- Department of Chemistry and Biochemistry, Miami University, Oxford, OH, USA 45056
| | - Gary A. Lorigan
- Department of Chemistry and Biochemistry, Miami University, Oxford, OH, USA 45056
| |
Collapse
|
11
|
Endl E, Beck-Sickinger A, Wilhelm C, Schlegel M, Müller S. The Wealth of Cytomics. Résumé of the 19th Annual Meeting of the German Society for Cytometry (Deutsche Gesellschaft Für Zytometrie, DGfZ). CYTOMETRY PART B-CLINICAL CYTOMETRY 2010; 78:361-3. [PMID: 20533394 DOI: 10.1002/cyto.b.20521] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Elmar Endl
- Institute for Molecular Medicine and Experimental Immunology, Bonn University, 53105 Bonn, Germany
| | | | | | | | | |
Collapse
|
12
|
Schmidt P, Lindner D, Montag C, Berndt S, Beck-Sickinger AG, Rudolph R, Huster D. Prokaryotic expression, in vitro folding, and molecular pharmacological characterization of the neuropeptide Y receptor type 2. Biotechnol Prog 2010; 25:1732-9. [PMID: 19725122 DOI: 10.1002/btpr.266] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
G protein-coupled receptors (GPCRs) are a class of membrane proteins that represent a major target for pharmacological developments. However, there is still little knowledge about GPCR structure and dynamics since high-level expression and characterization of active GPCRs in vitro is extremely complicated. Here, we describe the recombinant expression and functional folding of the human Y(2) receptor from inclusion bodies of E. coli cultures. Milligram protein quantities were produced using high density fermentation and isolated in a single step purification with a yield of over 20 mg/L culture. Extensive studies were carried out on in vitro refolding and stabilization of the isolated receptor in detergent solution. The specific binding of the ligand, the 36 residue neuropeptide Y (NPY), to the recombinant Y(2) receptors in micellar form was shown by several radioligand affinity assays. In competition experiments, an IC(50) value in low nanomolar range could be determined. Further, a K(D) value of 1.9 nM was determined from a saturation assay, where NPY was titrated to the recombinant Y(2) receptors.
Collapse
Affiliation(s)
- Peter Schmidt
- Institute of Medical Physics and Biophysics, University of Leipzig, Härtelstrasse 16-18, D-04107 Leipzig, Germany
| | | | | | | | | | | | | |
Collapse
|