1
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Sánchez-Hernández R, Benítez-Angeles M, Hernández-Vega AM, Rosenbaum T. Recent advances on the structure and the function relationships of the TRPV4 ion channel. Channels (Austin) 2024; 18:2313323. [PMID: 38354101 PMCID: PMC10868539 DOI: 10.1080/19336950.2024.2313323] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2023] [Accepted: 01/18/2024] [Indexed: 02/16/2024] Open
Abstract
The members of the superfamily of Transient Receptor Potential (TRP) ion channels are physiologically important molecules that have been studied for many years and are still being intensively researched. Among the vanilloid TRP subfamily, the TRPV4 ion channel is an interesting protein due to its involvement in several essential physiological processes and in the development of various diseases. As in other proteins, changes in its function that lead to the development of pathological states, have been closely associated with modification of its regulation by different molecules, but also by the appearance of mutations which affect the structure and gating of the channel. In the last few years, some structures for the TRPV4 channel have been solved. Due to the importance of this protein in physiology, here we discuss the recent progress in determining the structure of the TRPV4 channel, which has been achieved in three species of animals (Xenopus tropicalis, Mus musculus, and Homo sapiens), highlighting conserved features as well as key differences among them and emphasizing the binding sites for some ligands that play crucial roles in its regulation.
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Affiliation(s)
- Raúl Sánchez-Hernández
- Departamento de Neurociencia Cognitiva, División Neurociencias, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Mexico, Mexico
| | - Miguel Benítez-Angeles
- Departamento de Neurociencia Cognitiva, División Neurociencias, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Mexico, Mexico
| | - Ana M. Hernández-Vega
- Departamento de Neurociencia Cognitiva, División Neurociencias, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Mexico, Mexico
| | - Tamara Rosenbaum
- Departamento de Neurociencia Cognitiva, División Neurociencias, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Mexico, Mexico
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2
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Chaigne S, Barbeau S, Ducret T, Guinamard R, Benoist D. Pathophysiological Roles of the TRPV4 Channel in the Heart. Cells 2023; 12:1654. [PMID: 37371124 DOI: 10.3390/cells12121654] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Revised: 06/10/2023] [Accepted: 06/14/2023] [Indexed: 06/29/2023] Open
Abstract
The transient receptor potential vanilloid 4 (TRPV4) channel is a non-selective cation channel that is mostly permeable to calcium (Ca2+), which participates in intracellular Ca2+ handling in cardiac cells. It is widely expressed through the body and is activated by a large spectrum of physicochemical stimuli, conferring it a role in a variety of sensorial and physiological functions. Within the cardiovascular system, TRPV4 expression is reported in cardiomyocytes, endothelial cells (ECs) and smooth muscle cells (SMCs), where it modulates mitochondrial activity, Ca2+ homeostasis, cardiomyocytes electrical activity and contractility, cardiac embryonic development and fibroblast proliferation, as well as vascular permeability, dilatation and constriction. On the other hand, TRPV4 channels participate in several cardiac pathological processes such as the development of cardiac fibrosis, hypertrophy, ischemia-reperfusion injuries, heart failure, myocardial infarction and arrhythmia. In this manuscript, we provide an overview of TRPV4 channel implications in cardiac physiology and discuss the potential of the TRPV4 channel as a therapeutic target against cardiovascular diseases.
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Affiliation(s)
- Sébastien Chaigne
- IHU LIRYC Electrophysiology and Heart Modeling Institute, Fondation Bordeaux Université, 33600 Bordeaux, France
- Centre de Recherche Cardio-Thoracique de Bordeaux, INSERM U1045, University of Bordeaux, 33600 Pessac, France
- Electrophysiology and Ablation Unit, Bordeaux University Hospital, 33604 Pessac, France
| | - Solène Barbeau
- Centre de Recherche Cardio-Thoracique de Bordeaux, INSERM U1045, University of Bordeaux, 33600 Pessac, France
| | - Thomas Ducret
- Centre de Recherche Cardio-Thoracique de Bordeaux, INSERM U1045, University of Bordeaux, 33600 Pessac, France
| | - Romain Guinamard
- UR4650, Physiopathologie et Stratégies d'Imagerie du Remodelage Cardiovasculaire, GIP Cyceron, Université de Caen Normandie, 14032 Caen, France
| | - David Benoist
- IHU LIRYC Electrophysiology and Heart Modeling Institute, Fondation Bordeaux Université, 33600 Bordeaux, France
- Centre de Recherche Cardio-Thoracique de Bordeaux, INSERM U1045, University of Bordeaux, 33600 Pessac, France
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3
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Zeng ML, Kong S, Chen TX, Peng BW. Transient Receptor Potential Vanilloid 4: a Double-Edged Sword in the Central Nervous System. Mol Neurobiol 2023; 60:1232-1249. [PMID: 36434370 DOI: 10.1007/s12035-022-03141-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Accepted: 11/17/2022] [Indexed: 11/26/2022]
Abstract
Transient receptor potential vanilloid 4 (TRPV4) is a nonselective cation channel that can be activated by diverse stimuli, such as heat, mechanical force, hypo-osmolarity, and arachidonic acid metabolites. TRPV4 is widely expressed in the central nervous system (CNS) and participates in many significant physiological processes. However, accumulative evidence has suggested that deficiency, abnormal expression or distribution, and overactivation of TRPV4 are involved in pathological processes of multiple neurological diseases. Here, we review the latest studies concerning the known features of this channel, including its expression, structure, and its physiological and pathological roles in the CNS, proposing an emerging therapeutic strategy for CNS diseases.
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Affiliation(s)
- Meng-Liu Zeng
- Department of Physiology, Hubei Provincial Key Laboratory of Developmentally Originated Disease, Taikang Medical School (School of Basic Medical Sciences), Wuhan University, Donghu Rd185#, Wuhan, 430071, Hubei, China.,Medical Science Research Center, Zhongnan Hospital of Wuhan University, Wuhan, 430071, China
| | - Shuo Kong
- Department of Physiology, Hubei Provincial Key Laboratory of Developmentally Originated Disease, Taikang Medical School (School of Basic Medical Sciences), Wuhan University, Donghu Rd185#, Wuhan, 430071, Hubei, China
| | - Tao-Xiang Chen
- Department of Physiology, Hubei Provincial Key Laboratory of Developmentally Originated Disease, Taikang Medical School (School of Basic Medical Sciences), Wuhan University, Donghu Rd185#, Wuhan, 430071, Hubei, China
| | - Bi-Wen Peng
- Department of Physiology, Hubei Provincial Key Laboratory of Developmentally Originated Disease, Taikang Medical School (School of Basic Medical Sciences), Wuhan University, Donghu Rd185#, Wuhan, 430071, Hubei, China.
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4
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Moretti M, Limongi T, Testi C, Milanetti E, De Angelis MT, Parrotta EI, Scalise S, Santamaria G, Allione M, Lopatin S, Torre B, Zhang P, Marini M, Perozziello G, Candeloro P, Pirri CF, Ruocco G, Cuda G, Di Fabrizio E. Direct Visualization and Identification of Membrane Voltage-Gated Sodium Channels from Human iPSC-Derived Neurons by Multiple Imaging and Light Enhanced Spectroscopy. SMALL METHODS 2022; 6:e2200402. [PMID: 35595684 DOI: 10.1002/smtd.202200402] [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: 03/30/2022] [Revised: 04/22/2022] [Indexed: 06/15/2023]
Abstract
In this study, transmission electron microscopy atomic force microscopy, and surface enhanced Raman spectroscopy are combined through a direct imaging approach, to gather structural and chemical information of complex molecular systems such as ion channels in their original plasma membrane. Customized microfabricated sample holder allows to characterize Nav channels embedded in the original plasma membrane extracted from neuronal cells that are derived from healthy human induced pluripotent stem cells. The identification of the channels is accomplished by using two different approaches, one of them widely used in cryo-EM (the particle analysis method) and the other based on a novel Zernike Polynomial expansion of the images bitmap. This approach allows to carry out a whole series of investigations, one complementary to the other, on the same sample, preserving its state as close as possible to the original membrane configuration.
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Affiliation(s)
- Manola Moretti
- King Abdullah University of Science and Technology, SMILEs lab, PSE Division, Thuwal, 23955-6900, Kingdom of Saudi Arabia
| | - Tania Limongi
- Dipartimento di Scienza Applicata e Tecnologia, Politecnico di Torino, Corso Duca Degli Abruzzi 24, 10129, Torino, Italy
| | - Claudia Testi
- Center for Life Nanoscience, Istituto Italiano di Tecnologia, Viale Regina Elena 291, 00161, Rome, Italy
| | - Edoardo Milanetti
- Center for Life Nanoscience, Istituto Italiano di Tecnologia, Viale Regina Elena 291, 00161, Rome, Italy
- Department of Physics, Sapienza University, Piazzale Aldo Moro 5, Rome, 00185, Italy
| | - Maria Teresa De Angelis
- Laboratory of Stem Cell Biology, Department of Experimental and Clinical Medicine, University Magna Graecia, Campus S. Venuta, Viale Europa, Catanzaro, 88100, Italy
| | - Elvira I Parrotta
- Laboratory of Stem Cell Biology, Department of Experimental and Clinical Medicine, University Magna Graecia, Campus S. Venuta, Viale Europa, Catanzaro, 88100, Italy
| | - Stefania Scalise
- Laboratory of Stem Cell Biology, Department of Experimental and Clinical Medicine, University Magna Graecia, Campus S. Venuta, Viale Europa, Catanzaro, 88100, Italy
| | - Gianluca Santamaria
- Laboratory of Stem Cell Biology, Department of Experimental and Clinical Medicine, University Magna Graecia, Campus S. Venuta, Viale Europa, Catanzaro, 88100, Italy
| | - Marco Allione
- King Abdullah University of Science and Technology, SMILEs lab, PSE Division, Thuwal, 23955-6900, Kingdom of Saudi Arabia
| | - Sergei Lopatin
- King Abdullah University of Science and Technology, Imaging and Characterization Core lab, Thuwal, 23955-6900, Kingdom of Saudi Arabia
| | - Bruno Torre
- King Abdullah University of Science and Technology, SMILEs lab, PSE Division, Thuwal, 23955-6900, Kingdom of Saudi Arabia
| | - Peng Zhang
- King Abdullah University of Science and Technology, SMILEs lab, PSE Division, Thuwal, 23955-6900, Kingdom of Saudi Arabia
| | - Monica Marini
- Dipartimento di Scienza Applicata e Tecnologia, Politecnico di Torino, Corso Duca Degli Abruzzi 24, 10129, Torino, Italy
| | - Gerardo Perozziello
- BionNEM lab and Nanotechnology Research Center, Department of Experimental and Clinical Medicine, University Magna Graecia, Campus S. Venuta, Viale Europa, Catanzaro, 88100, Italy
| | - Patrizio Candeloro
- BionNEM lab and Nanotechnology Research Center, Department of Experimental and Clinical Medicine, University Magna Graecia, Campus S. Venuta, Viale Europa, Catanzaro, 88100, Italy
| | - Candido Fabrizio Pirri
- Dipartimento di Scienza Applicata e Tecnologia, Politecnico di Torino, Corso Duca Degli Abruzzi 24, 10129, Torino, Italy
| | - Giancarlo Ruocco
- Department of Physics, Sapienza University, Piazzale Aldo Moro 5, Rome, 00185, Italy
| | - Giovanni Cuda
- Laboratory of Stem Cell Biology, Department of Experimental and Clinical Medicine, University Magna Graecia, Campus S. Venuta, Viale Europa, Catanzaro, 88100, Italy
| | - Enzo Di Fabrizio
- Dipartimento di Scienza Applicata e Tecnologia, Politecnico di Torino, Corso Duca Degli Abruzzi 24, 10129, Torino, Italy
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5
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Wan H, Chen XY, Zhang F, Chen J, Chu F, Sellers ZM, Xu F, Dong H. Capsaicin inhibits intestinal Cl - secretion and promotes Na + absorption by blocking TRPV4 channels in healthy and colitic mice. J Biol Chem 2022; 298:101847. [PMID: 35314195 PMCID: PMC9035713 DOI: 10.1016/j.jbc.2022.101847] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Revised: 03/14/2022] [Accepted: 03/15/2022] [Indexed: 01/06/2023] Open
Abstract
Although capsaicin has been studied extensively as an activator of the transient receptor potential vanilloid cation channel subtype 1 (TRPV1) channels in sensory neurons, little is known about its TRPV1-independent actions in gastrointestinal health and disease. Here, we aimed to investigate the pharmacological actions of capsaicin as a food additive and medication on intestinal ion transporters in mouse models of ulcerative colitis (UC). The short-circuit current (Isc) of the intestine from WT, TRPV1-, and TRPV4-KO mice were measured in Ussing chambers, and Ca2+ imaging was performed on small intestinal epithelial cells. We also performed Western blots, immunohistochemistry, and immunofluorescence on intestinal epithelial cells and on intestinal tissues following UC induction with dextran sodium sulfate. We found that capsaicin did not affect basal intestinal Isc but significantly inhibited carbachol- and caffeine-induced intestinal Isc in WT mice. Capsaicin similarly inhibited the intestinal Isc in TRPV1 KO mice, but this inhibition was absent in TRPV4 KO mice. We also determined that Ca2+ influx via TRPV4 was required for cholinergic signaling–mediated intestinal anion secretion, which was inhibited by capsaicin. Moreover, the glucose-induced jejunal Iscvia Na+/glucose cotransporter was suppressed by TRPV4 activation, which could be relieved by capsaicin. Capsaicin also stimulated ouabain- and amiloride-sensitive colonic Isc. Finally, we found that dietary capsaicin ameliorated the UC phenotype, suppressed hyperaction of TRPV4 channels, and rescued the reduced ouabain- and amiloride-sensitive Isc. We therefore conclude that capsaicin inhibits intestinal Cl- secretion and promotes Na+ absorption predominantly by blocking TRPV4 channels to exert its beneficial anti-colitic action.
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Affiliation(s)
- Hanxing Wan
- Department of Pediatric Intensive Care Unit, Children's Hospital of Chongqing Medical University; National Clinical Research Center for Child Health and Disorders; Ministry of Education Key Laboratory of Child Development and Disorders; Chongqing Key Laboratory of Pediatrics, Chongqing, 400014, China
| | - Xiong Ying Chen
- Department of Pediatric Intensive Care Unit, Children's Hospital of Chongqing Medical University; National Clinical Research Center for Child Health and Disorders; Ministry of Education Key Laboratory of Child Development and Disorders; Chongqing Key Laboratory of Pediatrics, Chongqing, 400014, China
| | - Fenglian Zhang
- Department of Gastroenterology, Xinqiao Hospital, Army Medical University, Chongqing, 400037, China
| | - Jun Chen
- Department of Gastroenterology, Xinqiao Hospital, Army Medical University, Chongqing, 400037, China
| | - Fenglan Chu
- Department of Gastroenterology, Xinqiao Hospital, Army Medical University, Chongqing, 400037, China
| | - Zachary M Sellers
- Pediatric Gastroenterology Hepatology & Nutrition, Stanford University School of Medicine, Palo Alto, CA 94304, USA
| | - Feng Xu
- Department of Pediatric Intensive Care Unit, Children's Hospital of Chongqing Medical University; National Clinical Research Center for Child Health and Disorders; Ministry of Education Key Laboratory of Child Development and Disorders; Chongqing Key Laboratory of Pediatrics, Chongqing, 400014, China.
| | - Hui Dong
- Department of Pediatric Intensive Care Unit, Children's Hospital of Chongqing Medical University; National Clinical Research Center for Child Health and Disorders; Ministry of Education Key Laboratory of Child Development and Disorders; Chongqing Key Laboratory of Pediatrics, Chongqing, 400014, China; Department of Gastroenterology, Xinqiao Hospital, Army Medical University, Chongqing, 400037, China; Department of Medicine, School of Medicine, University of California, San Diego, CA 92093, USA.
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6
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Zhang X, Lee MD, Buckley C, Wilson C, McCarron JG. Mitochondria regulate TRPV4-mediated release of ATP. Br J Pharmacol 2022; 179:1017-1032. [PMID: 34605007 DOI: 10.1111/bph.15687] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Revised: 08/10/2021] [Accepted: 09/02/2021] [Indexed: 11/28/2022] Open
Abstract
BACKGROUND AND PURPOSE Ca2+ influx via TRPV4 channels triggers Ca2+ release from the IP3 -sensitive internal store to generate repetitive oscillations. Although mitochondria are acknowledged regulators of IP3 -mediated Ca2+ release, how TRPV4-mediated Ca2+ signals are regulated by mitochondria is unknown. We show that depolarised mitochondria switch TRPV4 signalling from relying on Ca2+ -induced Ca2+ release at IP3 receptors to being independent of Ca2+ influx and instead mediated by ATP release via pannexins. EXPERIMENTAL APPROACH TRPV4-evoked Ca2+ signals were individually examined in hundreds of cells in the endothelium of rat mesenteric resistance arteries using the indicator Cal520. KEY RESULTS TRPV4 activation with GSK1016790A (GSK) generated repetitive Ca2+ oscillations that required Ca2+ influx. However, when the mitochondrial membrane potential was depolarised, by the uncoupler CCCP or complex I inhibitor rotenone, TRPV4 activation generated large propagating, multicellular, Ca2+ waves in the absence of external Ca2+ . The ATP synthase inhibitor oligomycin did not potentiate TRPV4-mediated Ca2+ signals. GSK-evoked Ca2+ waves, when mitochondria were depolarised, were blocked by the TRPV4 channel blocker HC067047, the SERCA inhibitor cyclopiazonic acid, the PLC blocker U73122 and the inositol trisphosphate receptor blocker caffeine. The Ca2+ waves were also inhibited by the extracellular ATP blockers suramin and apyrase and the pannexin blocker probenecid. CONCLUSION AND IMPLICATIONS These results highlight a previously unknown role of mitochondria in shaping TRPV4-mediated Ca2+ signalling by facilitating ATP release. When mitochondria are depolarised, TRPV4-mediated release of ATP via pannexin channels activates plasma membrane purinergic receptors to trigger IP3 -evoked Ca2+ release.
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Affiliation(s)
- Xun Zhang
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, UK
| | - Matthew D Lee
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, UK
| | - Charlotte Buckley
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, UK
| | - Calum Wilson
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, UK
| | - John G McCarron
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, UK
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7
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Acharya TK, Sahu RP, Kumar S, Kumar S, Rokade TP, Chakraborty R, Dubey NK, Shikha D, Chawla S, Goswami C. Function and regulation of thermosensitive ion channel TRPV4 in the immune system. CURRENT TOPICS IN MEMBRANES 2022; 89:155-188. [DOI: 10.1016/bs.ctm.2022.07.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
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8
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Miller M, Koch SE, Veteto A, Domeier T, Rubinstein J. Role of Known Transient Receptor Potential Vanilloid Channels in Modulating Cardiac Mechanobiology. Front Physiol 2021; 12:734113. [PMID: 34867442 PMCID: PMC8637880 DOI: 10.3389/fphys.2021.734113] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Accepted: 08/27/2021] [Indexed: 12/17/2022] Open
Abstract
The transient receptor potential (TRP) channels have been described in almost every mammalian cell type. Several members of the Vanilloid (TRPV) subtype have been found to play important roles in modulating cardiac structure and function through Ca2+ handling in response to systemic and local mechanobiological cues. In this review, we will consider the most studied TRPV channels in the cardiovascular field; transient receptor potential vanilloid 1 as a modulator of cardiac hypertrophy; transient receptor potential vanilloid 2 as a structural and functional protein; transient receptor potential vanilloid 3 in the development of hypertrophy and myocardial fibrosis; and transient receptor potential vanilloid 4 in its roles modulating the fibrotic and functional responses of the heart to pressure overload. Lastly, we will also review the potential overlapping roles of these channels with other TRP proteins as well as the advances in translational and clinical arenas associated with TRPV channels.
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Affiliation(s)
- Michael Miller
- Department of Medical Pharmacology and Physiology, University of Missouri School of Medicine, Columbia, KY, United States
| | - Sheryl E Koch
- Department of Internal Medicine, Division of Cardiovascular Health and Disease, College of Medicine, University of Cincinnati Medical Center, Cincinnati, OH, United States
| | - Adam Veteto
- Department of Medical Pharmacology and Physiology, University of Missouri School of Medicine, Columbia, KY, United States.,IonOptix, LLC, Westwood, MA, United States
| | - Timothy Domeier
- Department of Medical Pharmacology and Physiology, University of Missouri School of Medicine, Columbia, KY, United States
| | - Jack Rubinstein
- Department of Internal Medicine, Division of Cardiovascular Health and Disease, College of Medicine, University of Cincinnati Medical Center, Cincinnati, OH, United States.,Division of Cardiovascular Medicine, Cincinnati Veterans Affairs Medical Center, Cincinnati, OH, United States
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9
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Chen M, Li X. Role of TRPV4 channel in vasodilation and neovascularization. Microcirculation 2021; 28:e12703. [PMID: 33971061 DOI: 10.1111/micc.12703] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Accepted: 05/02/2021] [Indexed: 12/12/2022]
Abstract
The transient receptor potential vanilloid type 4 (TRPV4) channel, a Ca2+ -permeable nonselective cation channel, is widely distributed in the circulatory system, particularly in vascular endothelial cells (ECs) and smooth muscle cells (SMCs). The TRPV4 channel is activated by various endogenous and exogenous stimuli, including shear stress, low intravascular pressure, and arachidonic acid. TRPV4 has a role in mediating vascular tone and arterial blood pressure. The activation of the TRPV4 channel induces Ca2+ influx, thereby resulting in endothelium-dependent hyperpolarization and SMC relaxation through SKCa and IKCa activation on ECs or through BKCa activation on SMCs. Ca2+ binds to calmodulin, which leads to the production of nitric oxide, causing vasodilation. Furthermore, the TRPV4 channel plays an important role in angiogenesis and arteriogenesis and is critical for tumor angiogenesis and growth, since it promotes or inhibits the development of various types of cancer. The TRPV4 channel is involved in the active growth of collateral arteries induced by flow shear stress, which makes it a promising therapeutic target in the occlusion or stenosis of the main arteries. In this review, we explore the role and the potential mechanism of action of the TRPV4 channel in the regulation of vascular tone and in the induction of neovascularization to provide a reference for future research.
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Affiliation(s)
- Miao Chen
- Department of Hand and Foot Surgery, The First Hospital of Jilin University, Changchun, China
| | - Xiucun Li
- Department of Hand and Foot Surgery, The Second Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China.,Department of Anatomy and Histoembryology, School of Basic Medical Science, Cheeloo College of Medicine, Shandong University, Jinan, China
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10
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Goretzki B, Guhl C, Tebbe F, Harder JM, Hellmich UA. Unstructural Biology of TRP Ion Channels: The Role of Intrinsically Disordered Regions in Channel Function and Regulation. J Mol Biol 2021; 433:166931. [PMID: 33741410 DOI: 10.1016/j.jmb.2021.166931] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2021] [Revised: 03/02/2021] [Accepted: 03/06/2021] [Indexed: 12/13/2022]
Abstract
The first genuine high-resolution single particle cryo-electron microscopy structure of a membrane protein determined was a transient receptor potential (TRP) ion channel, TRPV1, in 2013. This methodical breakthrough opened up a whole new world for structural biology and ion channel aficionados alike. TRP channels capture the imagination due to the sheer endless number of tasks they carry out in all aspects of animal physiology. To date, structures of at least one representative member of each of the six mammalian TRP channel subfamilies as well as of a few non-mammalian families have been determined. These structures were instrumental for a better understanding of TRP channel function and regulation. However, all of the TRP channel structures solved so far are incomplete since they miss important information about highly flexible regions found mostly in the channel N- and C-termini. These intrinsically disordered regions (IDRs) can represent between a quarter to almost half of the entire protein sequence and act as important recruitment hubs for lipids and regulatory proteins. Here, we analyze the currently available TRP channel structures with regard to the extent of these "missing" regions and compare these findings to disorder predictions. We discuss select examples of intra- and intermolecular crosstalk of TRP channel IDRs with proteins and lipids as well as the effect of splicing and post-translational modifications, to illuminate their importance for channel function and to complement the prevalently discussed structural biology of these versatile and fascinating proteins with their equally relevant 'unstructural' biology.
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Affiliation(s)
- Benedikt Goretzki
- Faculty of Chemistry and Earth Sciences, Institute of Organic Chemistry and Macromolecular Chemistry, Friedrich-Schiller-University, Humboldtstrasse 10, 07743 Jena, Germany; Centre for Biomolecular Magnetic Resonance (BMRZ), Goethe-University, Max-von-Laue-Strasse 9, 60438 Frankfurt, Germany
| | - Charlotte Guhl
- Faculty of Chemistry and Earth Sciences, Institute of Organic Chemistry and Macromolecular Chemistry, Friedrich-Schiller-University, Humboldtstrasse 10, 07743 Jena, Germany; Centre for Biomolecular Magnetic Resonance (BMRZ), Goethe-University, Max-von-Laue-Strasse 9, 60438 Frankfurt, Germany; TransMED - Mainz Research School of Translational Medicine, Johannes Gutenberg-University, University Medical Center, Langenbeckstr. 1, 55131 Mainz, Germany
| | - Frederike Tebbe
- Faculty of Chemistry and Earth Sciences, Institute of Organic Chemistry and Macromolecular Chemistry, Friedrich-Schiller-University, Humboldtstrasse 10, 07743 Jena, Germany; Centre for Biomolecular Magnetic Resonance (BMRZ), Goethe-University, Max-von-Laue-Strasse 9, 60438 Frankfurt, Germany
| | - Jean-Martin Harder
- Faculty of Chemistry and Earth Sciences, Institute of Organic Chemistry and Macromolecular Chemistry, Friedrich-Schiller-University, Humboldtstrasse 10, 07743 Jena, Germany
| | - Ute A Hellmich
- Faculty of Chemistry and Earth Sciences, Institute of Organic Chemistry and Macromolecular Chemistry, Friedrich-Schiller-University, Humboldtstrasse 10, 07743 Jena, Germany; Centre for Biomolecular Magnetic Resonance (BMRZ), Goethe-University, Max-von-Laue-Strasse 9, 60438 Frankfurt, Germany; TransMED - Mainz Research School of Translational Medicine, Johannes Gutenberg-University, University Medical Center, Langenbeckstr. 1, 55131 Mainz, Germany; Cluster of Excellence Balance of the Microverse, Friedrich-Schiller-University, 07743 Jena, Germany.
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11
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Molecular modeling of three-dimensional structure of hTRPV4 protein and experimental verification of its antagonist binding sites. J Mol Struct 2021. [DOI: 10.1016/j.molstruc.2020.129421] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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12
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TRPing to the Point of Clarity: Understanding the Function of the Complex TRPV4 Ion Channel. Cells 2021; 10:cells10010165. [PMID: 33467654 PMCID: PMC7830798 DOI: 10.3390/cells10010165] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Revised: 01/12/2021] [Accepted: 01/13/2021] [Indexed: 02/07/2023] Open
Abstract
The transient receptor potential vanilloid 4 channel (TRPV4) belongs to the mammalian TRP superfamily of cation channels. TRPV4 is ubiquitously expressed, activated by a disparate array of stimuli, interacts with a multitude of proteins, and is modulated by a range of post-translational modifications, the majority of which we are only just beginning to understand. Not surprisingly, a great number of physiological roles have emerged for TRPV4, as have various disease states that are attributable to the absence, or abnormal functioning, of this ion channel. This review will highlight structural features of TRPV4, endogenous and exogenous activators of the channel, and discuss the reported roles of TRPV4 in health and disease.
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13
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Malac M, Hettler S, Hayashida M, Kano E, Egerton RF, Beleggia M. Phase plates in the transmission electron microscope: operating principles and applications. Microscopy (Oxf) 2020; 70:75-115. [DOI: 10.1093/jmicro/dfaa070] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Revised: 10/30/2020] [Accepted: 12/11/2020] [Indexed: 01/19/2023] Open
Abstract
Abstract
In this paper, we review the current state of phase plate imaging in a transmission electron microscope. We focus especially on the hole-free phase plate design, also referred to as the Volta phase plate. We discuss the implementation, operating principles and applications of phase plate imaging. We provide an imaging theory that accounts for inelastic scattering in both the sample and in the hole-free phase plate.
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Affiliation(s)
- Marek Malac
- NRC-NANO, National Research Council, 11421 Saskatchewan Drive, Edmonton, Alberta T6G 2M9, Canada
- Department of Physics, University of Alberta, Edmonton, Alberta T6G 2E1, Canada
| | - Simon Hettler
- Laboratorio de Microscopías Avanzadas (LMA), Instituto de Nanociencia y Materiales de Aragon (INMA), Universidad de Zaragoza, Campus Río Ebro, 50018 Zaragoza, España
| | - Misa Hayashida
- NRC-NANO, National Research Council, 11421 Saskatchewan Drive, Edmonton, Alberta T6G 2M9, Canada
| | - Emi Kano
- Institute of Materials and Systems for Sustainability, Nagoya University, Nagoya, Aichi 464-8601, Japan
| | - Ray F Egerton
- Department of Physics, University of Alberta, Edmonton, Alberta T6G 2E1, Canada
| | - Marco Beleggia
- DTU Nanolab, Technical University of Denmark, 2800 Kgs. Lyngby, Denmark
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14
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Achanta S, Jordt SE. Transient receptor potential channels in pulmonary chemical injuries and as countermeasure targets. Ann N Y Acad Sci 2020; 1480:73-103. [PMID: 32892378 PMCID: PMC7933981 DOI: 10.1111/nyas.14472] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Revised: 07/22/2020] [Accepted: 07/29/2020] [Indexed: 12/17/2022]
Abstract
The lung is highly sensitive to chemical injuries caused by exposure to threat agents in industrial or transportation accidents, occupational exposures, or deliberate use as weapons of mass destruction (WMD). There are no antidotes for the majority of the chemical threat agents and toxic inhalation hazards despite their use as WMDs for more than a century. Among several putative targets, evidence for transient receptor potential (TRP) ion channels as mediators of injury by various inhalational chemical threat agents is emerging. TRP channels are expressed in the respiratory system and are essential for homeostasis. Among TRP channels, the body of literature supporting essential roles for TRPA1, TRPV1, and TRPV4 in pulmonary chemical injuries is abundant. TRP channels mediate their function through sensory neuronal and nonneuronal pathways. TRP channels play a crucial role in complex pulmonary pathophysiologic events including, but not limited to, increased intracellular calcium levels, signal transduction, recruitment of proinflammatory cells, neurogenic inflammatory pathways, cough reflex, hampered mucus clearance, disruption of the integrity of the epithelia, pulmonary edema, and fibrosis. In this review, we summarize the role of TRP channels in chemical threat agents-induced pulmonary injuries and how these channels may serve as medical countermeasure targets for broader indications.
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Affiliation(s)
- Satyanarayana Achanta
- Department of Anesthesiology, Duke University School of Medicine, Durham, North Carolina
| | - Sven-Eric Jordt
- Department of Anesthesiology, Duke University School of Medicine, Durham, North Carolina
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, North Carolina
- Department of Psychiatry, Yale University School of Medicine, New Haven, Connecticut
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15
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Silverman HA, Chen A, Kravatz NL, Chavan SS, Chang EH. Involvement of Neural Transient Receptor Potential Channels in Peripheral Inflammation. Front Immunol 2020; 11:590261. [PMID: 33193423 PMCID: PMC7645044 DOI: 10.3389/fimmu.2020.590261] [Citation(s) in RCA: 77] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Accepted: 09/30/2020] [Indexed: 12/11/2022] Open
Abstract
Transient receptor potential (TRP) channels are a superfamily of non-selective cation channels that act as polymodal sensors in many tissues throughout mammalian organisms. In the context of ion channels, they are unique for their broad diversity of activation mechanisms and their cation selectivity. TRP channels are involved in a diverse range of physiological processes including chemical sensing, nociception, and mediating cytokine release. They also play an important role in the regulation of inflammation through sensory function and the release of neuropeptides. In this review, we discuss the functional contribution of a subset of TRP channels (TRPV1, TRPV4, TRPM3, TRPM8, and TRPA1) that are involved in the body’s immune responses, particularly in relation to inflammation. We focus on these five TRP channels because, in addition to being expressed in many somatic cell types, these channels are also expressed on peripheral ganglia and nerves that innervate visceral organs and tissues throughout the body. Activation of these neural TRP channels enables crosstalk between neurons, immune cells, and epithelial cells to regulate a wide range of inflammatory actions. TRP channels act either through direct effects on cation levels or through indirect modulation of intracellular pathways to trigger pro- or anti-inflammatory mechanisms, depending on the inflammatory disease context. The expression of TRP channels on both neural and immune cells has made them an attractive drug target in diseases involving inflammation. Future work in this domain will likely yield important new pathways and therapies for the treatment of a broad range of disorders including colitis, dermatitis, sepsis, asthma, and pain.
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Affiliation(s)
- Harold A Silverman
- Laboratory of Biomedical Science, Feinstein Institutes for Medical Research, Northwell Health, Manhasset, NY, United States.,Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Northwell Health, Manhasset, NY, United States
| | - Adrian Chen
- Laboratory of Biomedical Science, Feinstein Institutes for Medical Research, Northwell Health, Manhasset, NY, United States.,Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Northwell Health, Manhasset, NY, United States
| | - Nigel L Kravatz
- Laboratory of Biomedical Science, Feinstein Institutes for Medical Research, Northwell Health, Manhasset, NY, United States.,Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Northwell Health, Manhasset, NY, United States
| | - Sangeeta S Chavan
- Laboratory of Biomedical Science, Feinstein Institutes for Medical Research, Northwell Health, Manhasset, NY, United States.,Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Northwell Health, Manhasset, NY, United States.,Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Hofstra University, Hempstead, NY, United States
| | - Eric H Chang
- Laboratory of Biomedical Science, Feinstein Institutes for Medical Research, Northwell Health, Manhasset, NY, United States.,Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Northwell Health, Manhasset, NY, United States.,Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Hofstra University, Hempstead, NY, United States
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16
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Sato D, Hernández-Hernández G, Matsumoto C, Tajada S, Moreno CM, Dixon RE, O'Dwyer S, Navedo MF, Trimmer JS, Clancy CE, Binder MD, Santana LF. A stochastic model of ion channel cluster formation in the plasma membrane. J Gen Physiol 2019; 151:1116-1134. [PMID: 31371391 PMCID: PMC6719406 DOI: 10.1085/jgp.201912327] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2019] [Revised: 07/05/2019] [Accepted: 07/08/2019] [Indexed: 12/24/2022] Open
Abstract
Ion channels are often found arranged into dense clusters in the plasma membranes of excitable cells, but the mechanisms underlying the formation and maintenance of these functional aggregates are unknown. Here, we tested the hypothesis that channel clustering is the consequence of a stochastic self-assembly process and propose a model by which channel clusters are formed and regulated in size. Our hypothesis is based on statistical analyses of the size distributions of the channel clusters we measured in neurons, ventricular myocytes, arterial smooth muscle, and heterologous cells, which in all cases were described by exponential functions, indicative of a Poisson process (i.e., clusters form in a continuous, independent, and memory-less fashion). We were able to reproduce the observed cluster distributions of five different types of channels in the membrane of excitable and tsA-201 cells in simulations using a computer model in which channels are "delivered" to the membrane at randomly assigned locations. The model's three parameters represent channel cluster nucleation, growth, and removal probabilities, the values of which were estimated based on our experimental measurements. We also determined the time course of cluster formation and membrane dwell time for CaV1.2 and TRPV4 channels expressed in tsA-201 cells to constrain our model. In addition, we elaborated a more complex version of our model that incorporated a self-regulating feedback mechanism to shape channel cluster formation. The strong inference we make from our results is that CaV1.2, CaV1.3, BK, and TRPV4 proteins are all randomly inserted into the plasma membranes of excitable cells and that they form homogeneous clusters that increase in size until they reach a steady state. Further, it appears likely that cluster size for a diverse set of membrane-bound proteins and a wide range of cell types is regulated by a common feedback mechanism.
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Affiliation(s)
- Daisuke Sato
- Department of Pharmacology, University of California School of Medicine, Davis, CA
| | | | - Collin Matsumoto
- Department of Physiology and Membrane Biology, University of California School of Medicine, Davis, CA
| | - Sendoa Tajada
- Department of Physiology and Membrane Biology, University of California School of Medicine, Davis, CA
| | - Claudia M Moreno
- Department of Physiology and Membrane Biology, University of California School of Medicine, Davis, CA
- Department of Physiology and Biophysics, University of Washington School of Medicine, Seattle, WA
| | - Rose E Dixon
- Department of Physiology and Membrane Biology, University of California School of Medicine, Davis, CA
| | - Samantha O'Dwyer
- Department of Physiology and Membrane Biology, University of California School of Medicine, Davis, CA
| | - Manuel F Navedo
- Department of Pharmacology, University of California School of Medicine, Davis, CA
| | - James S Trimmer
- Department of Physiology and Membrane Biology, University of California School of Medicine, Davis, CA
| | - Colleen E Clancy
- Department of Physiology and Membrane Biology, University of California School of Medicine, Davis, CA
| | - Marc D Binder
- Department of Physiology and Biophysics, University of Washington School of Medicine, Seattle, WA
| | - L Fernando Santana
- Department of Physiology and Membrane Biology, University of California School of Medicine, Davis, CA
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17
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Wang HW, Fan X. Challenges and opportunities in cryo-EM with phase plate. Curr Opin Struct Biol 2019; 58:175-182. [PMID: 31374473 DOI: 10.1016/j.sbi.2019.06.013] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Revised: 06/24/2019] [Accepted: 06/26/2019] [Indexed: 12/15/2022]
Abstract
Not long after the invention of transmission electron microscope (TEM), phase plate was proposed as a novel electron-optical apparatus at the back-focal plane of the objective lens to modulate the magnified specimen images with enhanced contrast, especially in cryo-electron microscopy (cryo-EM) application of biological specimens. In the past two decades, novel phase plates of different kinds were designed and fabricated for cryo-EM application. Some of them such as the Volta phase plate have already been proved very useful in single particle cryo-EM and cryo-electron tomography (cryo-ET) analysis. In this review, we discuss the current progress, challenges and opportunities of cryo-EM with phase plate.
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Affiliation(s)
- Hong-Wei Wang
- Ministry of Education Key Laboratory of Protein Sciences, Beijing Advanced Innovation Center for Structural Biology, Beijing Frontier Research Center of Biological Structures, School of Life Sciences, Tsinghua University, Beijing 100084, China; Tsinghua-Peking Joint Center for Life Sciences, Tsinghua University, Beijing 100084, China.
| | - Xiao Fan
- Ministry of Education Key Laboratory of Protein Sciences, Beijing Advanced Innovation Center for Structural Biology, Beijing Frontier Research Center of Biological Structures, School of Life Sciences, Tsinghua University, Beijing 100084, China; Tsinghua-Peking Joint Center for Life Sciences, Tsinghua University, Beijing 100084, China
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18
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Wen H, Zheng W. Decrypting the Heat Activation Mechanism of TRPV1 Channel by Molecular Dynamics Simulation. Biophys J 2019; 114:40-52. [PMID: 29320695 DOI: 10.1016/j.bpj.2017.10.034] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Revised: 10/11/2017] [Accepted: 10/23/2017] [Indexed: 11/29/2022] Open
Abstract
As a prototype cellular sensor, the TRPV1 cation channel undergoes a closed-to-open gating transition in response to various physical and chemical stimuli including noxious heat. Despite recent progress, the molecular mechanism of heat activation of TRPV1 gating remains enigmatic. Toward decrypting the structural basis of TRPV1 heat activation, we performed extensive molecular dynamics simulations (with cumulative simulation time of ∼11 μs) for the wild-type channel and a constitutively active double mutant at different temperatures (30, 60, and 72°C), starting from a high-resolution closed-channel structure of TRPV1 solved by cryo-electron microscopy. In the wild-type simulations, we observed heat-activated conformational changes (e.g., expansion or contraction) in various key domains of TRPV1 (e.g., the S2-S3 and S4-S5 linkers) to prime the channel for gating. These conformational changes involve a number of dynamic hydrogen-bond interactions that were validated with previous mutational studies. Next, our mutant simulations observed channel opening after a series of conformational changes that propagate from the channel periphery to the channel pore via key intermediate domains (including the S2-S3 and S4-S5 linkers). The gating transition is accompanied by a large increase in the protein-water electrostatic interaction energy, which supports the contribution of desolvation of polar/charged residues to the temperature-sensitive TRPV1 gating. Taken together, our molecular dynamics simulations and analyses offered, to our knowledge, new structural, dynamic, and energetic information to guide future mutagenesis and functional studies of the TRPV1 channels and development of TRPV1-targeting drugs.
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Affiliation(s)
- Han Wen
- Department of Physics, State University of New York at Buffalo, Buffalo, New York
| | - Wenjun Zheng
- Department of Physics, State University of New York at Buffalo, Buffalo, New York.
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19
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Zheng W, Wen H. Heat activation mechanism of TRPV1: New insights from molecular dynamics simulation. Temperature (Austin) 2019; 6:120-131. [PMID: 31286023 DOI: 10.1080/23328940.2019.1578634] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Revised: 12/30/2018] [Accepted: 01/30/2019] [Indexed: 02/07/2023] Open
Abstract
As a member of the transient receptor potential (TRP) channels superfamily, the TRPV1 channel undergoes a closed-to-open gating transition in response to various physical and chemical stimuli including heat. Thanks to recent progress in cryo-electron microscopy, high-resolution structures are becoming available for various TRP channels including TRPV1. This has enabled us to study the molecular mechanism of TRPV1 channel gating by using molecular simulation. Here we review recent progress in molecular simulations of TRPV1 channel by us and others, with focus on our molecular dynamics (MD) simulations of TRPV1 at different temperatures. While no consensus has been reached on the heat activation mechanism of TRPV1, the simulations have offered specific predictions and models for future experimental studies to test.
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Affiliation(s)
- Wenjun Zheng
- Department of Physics, State University of New York at Buffalo, Buffalo, NY, USA
| | - Han Wen
- Department of Physics, State University of New York at Buffalo, Buffalo, NY, USA
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20
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Membrane protein structural biology in the era of single particle cryo-EM. Curr Opin Struct Biol 2018; 52:58-63. [PMID: 30219656 DOI: 10.1016/j.sbi.2018.08.008] [Citation(s) in RCA: 98] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2018] [Revised: 05/15/2018] [Accepted: 08/29/2018] [Indexed: 11/22/2022]
Abstract
In the past few years, significant technological breakthroughs in single particle cryo-electron microscopy enabled a 'resolution revolution' of this technique. It also changed structural biology in an unprecedented way. For many biological macromolecules, obtaining well-ordered crystals of suitable size is no longer a prerequisite for determining their atomic structures. One of the most impacted areas is the structural biology of integral membrane proteins. New structures are now determined at a rapid pace. Despite these advances, further technological developments are still required to overcome new technical challenges that face membrane protein structural biology. In this review, I attempt to discuss some of these challenges.
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21
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Lal S, Scarinci N, Perez PL, Cantero MDR, Cantiello HF. Lipid bilayer-atomic force microscopy combined platform records simultaneous electrical and topological changes of the TRP channel polycystin-2 (TRPP2). PLoS One 2018; 13:e0202029. [PMID: 30133487 PMCID: PMC6104948 DOI: 10.1371/journal.pone.0202029] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2018] [Accepted: 07/26/2018] [Indexed: 11/30/2022] Open
Abstract
Ion channels are transmembrane proteins that mediate ion transport across biological membranes. Ion channel function is traditionally characterized by electrical parameters acquired with techniques such as patch-clamping and reconstitution in lipid bilayer membranes (BLM) that provide relevant information such as ionic conductance, selectivity, and gating properties. High resolution structural information of ion channels however, requires independent technologies, of which atomic force microscopy (AFM) is the only one that provides topological features of single functional channel proteins in their native environments. To date practically no data exist on direct correlations between electrical features and topological parameters from functional single channel complexes. Here, we report the design and construction of a BLM reconstitution microchamber that supports the simultaneous recording of electrical currents and AFM imaging from single channel complexes. As proof-of-principle, we tested the technique on polycystin-2 (PC2, TRPP2), a TRP channel family member from which we had previously elucidated its tetrameric topology by AFM imaging, and single channel currents by the BLM technique. The experimental setup provided direct structural-functional correlates from PC2 single channel complexes that disclosed novel topological changes between the closed and open sub-conductance states of the functional channel, namely, an inverse correlation between conductance and height of the channel. Unexpectedly, we also disclosed intrinsic PC2 mechanosensitivity in response to external forces. The platform provides a suitable means of accessing topological information to correlate with ion channel electrical parameters essential to understand the physiology of these transmembrane proteins.
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Affiliation(s)
- Sumit Lal
- Nephrology Division and Electrophysiology Core, Massachusetts General Hospital, Charlestown, Massachusetts, United States of America
| | - Noelia Scarinci
- Laboratorio de Canales Iónicos, Instituto Multidisciplinario de Salud, Tecnología y Desarrollo, IMSaTeD (UNSE-CONICET), Santiago del Estero, Argentina
| | - Paula L. Perez
- Laboratorio de Canales Iónicos, Instituto Multidisciplinario de Salud, Tecnología y Desarrollo, IMSaTeD (UNSE-CONICET), Santiago del Estero, Argentina
| | - María del Rocío Cantero
- Laboratorio de Canales Iónicos, Instituto Multidisciplinario de Salud, Tecnología y Desarrollo, IMSaTeD (UNSE-CONICET), Santiago del Estero, Argentina
| | - Horacio F. Cantiello
- Nephrology Division and Electrophysiology Core, Massachusetts General Hospital, Charlestown, Massachusetts, United States of America
- Laboratorio de Canales Iónicos, Instituto Multidisciplinario de Salud, Tecnología y Desarrollo, IMSaTeD (UNSE-CONICET), Santiago del Estero, Argentina
- Harvard Medical School, Boston, Massachusetts, United States of America
- * E-mail:
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22
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Deng Z, Paknejad N, Maksaev G, Sala-Rabanal M, Nichols CG, Hite RK, Yuan P. Cryo-EM and X-ray structures of TRPV4 reveal insight into ion permeation and gating mechanisms. Nat Struct Mol Biol 2018; 25:252-260. [PMID: 29483651 DOI: 10.1038/s41594-018-0037-5] [Citation(s) in RCA: 148] [Impact Index Per Article: 24.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2017] [Accepted: 01/26/2018] [Indexed: 12/15/2022]
Abstract
The transient receptor potential (TRP) channel TRPV4 participates in multiple biological processes, and numerous TRPV4 mutations underlie several distinct and devastating diseases. Here we present the cryo-EM structure of Xenopus tropicalis TRPV4 at 3.8-Å resolution. The ion-conduction pore contains an intracellular gate formed by the inner helices, but lacks any extracellular gate in the selectivity filter, as observed in other TRPV channels. Anomalous X-ray diffraction analyses identify a single ion-binding site in the selectivity filter, thus explaining TRPV4 nonselectivity. Structural comparisons with other TRP channels and distantly related voltage-gated cation channels reveal an unprecedented, unique packing interface between the voltage-sensor-like domain and the pore domain, suggesting distinct gating mechanisms. Moreover, our structure begins to provide mechanistic insights to the large set of pathogenic mutations, offering potential opportunities for drug development.
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Affiliation(s)
- Zengqin Deng
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO, USA.,Center for the Investigation of Membrane Excitability Diseases, Washington University School of Medicine, St. Louis, MO, USA
| | - Navid Paknejad
- Structural Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Grigory Maksaev
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO, USA.,Center for the Investigation of Membrane Excitability Diseases, Washington University School of Medicine, St. Louis, MO, USA
| | - Monica Sala-Rabanal
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO, USA.,Center for the Investigation of Membrane Excitability Diseases, Washington University School of Medicine, St. Louis, MO, USA
| | - Colin G Nichols
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO, USA.,Center for the Investigation of Membrane Excitability Diseases, Washington University School of Medicine, St. Louis, MO, USA
| | - Richard K Hite
- Structural Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY, USA.
| | - Peng Yuan
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO, USA. .,Center for the Investigation of Membrane Excitability Diseases, Washington University School of Medicine, St. Louis, MO, USA.
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23
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Martinac B, Poole K. Mechanically activated ion channels. Int J Biochem Cell Biol 2018; 97:104-107. [PMID: 29471041 DOI: 10.1016/j.biocel.2018.02.011] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2017] [Revised: 01/31/2018] [Accepted: 02/14/2018] [Indexed: 12/24/2022]
Abstract
The ability of cells to sense and respond to their physical environment is fundamental to a broad spectrum of biological processes. Cells express an array of force sensors that can transduce mechanical inputs into biochemical signals, including the mechanically activated ion channels PIEZO1, PIEZO2 and TRPV4. The identification and characterisation of mechanically activated ion channels has proven challenging, as has identifying their mode of activation and regulation in vivo. However, the diverse channelopathies associated with the known channels highlights their physiological importance.
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Affiliation(s)
- Boris Martinac
- Victor Chang Cardiac Research Institute, Darlinghurst, NSW, Australia; St Vincent's Clinical School, UNSW Darlinghurst, NSW 2010, Australia
| | - Kate Poole
- EMBL Australia Node in Single Molecule Science, School of Medical Sciences, UNSW Sydney, Sydney, NSW, 2052, Australia.
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24
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Jiang M, Karasawa T, Steyger PS. Aminoglycoside-Induced Cochleotoxicity: A Review. Front Cell Neurosci 2017; 11:308. [PMID: 29062271 PMCID: PMC5640705 DOI: 10.3389/fncel.2017.00308] [Citation(s) in RCA: 171] [Impact Index Per Article: 24.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2017] [Accepted: 09/15/2017] [Indexed: 12/20/2022] Open
Abstract
Aminoglycoside antibiotics are used as prophylaxis, or urgent treatment, for many life-threatening bacterial infections, including tuberculosis, sepsis, respiratory infections in cystic fibrosis, complex urinary tract infections and endocarditis. Although aminoglycosides are clinically-essential antibiotics, the mechanisms underlying their selective toxicity to the kidney and inner ear continue to be unraveled despite more than 70 years of investigation. The following mechanisms each contribute to aminoglycoside-induced toxicity after systemic administration: (1) drug trafficking across endothelial and epithelial barrier layers; (2) sensory cell uptake of these drugs; and (3) disruption of intracellular physiological pathways. Specific factors can increase the risk of drug-induced toxicity, including sustained exposure to higher levels of ambient sound, and selected therapeutic agents such as loop diuretics and glycopeptides. Serious bacterial infections (requiring life-saving aminoglycoside treatment) induce systemic inflammatory responses that also potentiate the degree of ototoxicity and permanent hearing loss. We discuss prospective clinical strategies to protect auditory and vestibular function from aminoglycoside ototoxicity, including reduced cochlear or sensory cell uptake of aminoglycosides, and otoprotection by ameliorating intracellular cytotoxicity.
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Affiliation(s)
- Meiyan Jiang
- Oregon Hearing Research Center, Oregon Health & Science University, Portland, OR, United States
| | - Takatoshi Karasawa
- Oregon Hearing Research Center, Oregon Health & Science University, Portland, OR, United States
| | - Peter S Steyger
- Oregon Hearing Research Center, Oregon Health & Science University, Portland, OR, United States.,National Center for Rehabilitative Auditory Research, Portland VA Medical Center (VHA), Portland, OR, United States
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25
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Toft-Bertelsen TL, Križaj D, MacAulay N. When size matters: transient receptor potential vanilloid 4 channel as a volume-sensor rather than an osmo-sensor. J Physiol 2017; 595:3287-3302. [PMID: 28295351 DOI: 10.1113/jp274135] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2017] [Accepted: 03/07/2017] [Indexed: 12/11/2022] Open
Abstract
KEY POINTS Mammalian cells are frequently exposed to stressors causing volume changes. The transient receptor potential vanilloid 4 (TRPV4) channel translates osmotic stress into ion flux. The molecular mechanism coupling osmolarity to TRPV4 activation remains elusive. TRPV4 responds to isosmolar cell swelling and osmolarity translated via different aquaporins. TRPV4 functions as a volume-sensing ion channel irrespective of the origin of the cell swelling. ABSTRACT Transient receptor potential channel 4 of the vanilloid subfamily (TRPV4) is activated by a diverse range of molecular cues, such as heat, lipid metabolites and synthetic agonists, in addition to hyposmotic challenges. As a non-selective cation channel permeable to Ca2+ , it transduces physical stress in the form of osmotic cell swelling into intracellular Ca2+ -dependent signalling events. Its contribution to cell volume regulation might include interactions with aquaporin (AQP) water channel isoforms, although the proposed requirement for a TRPV4-AQP4 macromolecular complex remains to be resolved. To characterize the elusive mechanics of TRPV4 volume-sensing, we expressed the channel in Xenopus laevis oocytes together with AQP4. Co-expression with AQP4 facilitated the cell swelling induced by osmotic challenges and thereby activated TRPV4-mediated transmembrane currents. Similar TRPV4 activation was induced by co-expression of a cognate channel, AQP1. The level of osmotically-induced TRPV4 activation, although proportional to the degree of cell swelling, was dependent on the rate of volume changes. Importantly, isosmotic cell swelling obtained by parallel activation of the co-expressed water-translocating Na+ /K+ /2Cl- cotransporter promoted TRPV4 activation despite the absence of the substantial osmotic gradients frequently employed for activation. Upon simultaneous application of an osmotic gradient and the selective TRPV4 agonist GSK1016790A, enhanced TRPV4 activation was observed only with subsaturating stimuli, indicating that the agonist promotes channel opening similar to that of volume-dependent activation. We propose that, contrary to the established paradigm, TRPV4 is activated by increased cell volume irrespective of the molecular mechanism underlying cell swelling. Thus, the channel functions as a volume-sensor, rather than as an osmo-sensor.
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Affiliation(s)
- Trine L Toft-Bertelsen
- Department of Neuroscience and Pharmacology, University of Copenhagen, Copenhagen, Denmark
| | - David Križaj
- Department of Ophthalmology & Visual Sciences, Moran Eye Institute, University of Utah School of Medicine, Salt Lake City, UT, USA
| | - Nanna MacAulay
- Department of Neuroscience and Pharmacology, University of Copenhagen, Copenhagen, Denmark
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26
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White JPM, Cibelli M, Urban L, Nilius B, McGeown JG, Nagy I. TRPV4: Molecular Conductor of a Diverse Orchestra. Physiol Rev 2017; 96:911-73. [PMID: 27252279 DOI: 10.1152/physrev.00016.2015] [Citation(s) in RCA: 261] [Impact Index Per Article: 37.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Transient receptor potential vanilloid type 4 (TRPV4) is a calcium-permeable nonselective cation channel, originally described in 2000 by research teams led by Schultz (Nat Cell Biol 2: 695-702, 2000) and Liedtke (Cell 103: 525-535, 2000). TRPV4 is now recognized as being a polymodal ionotropic receptor that is activated by a disparate array of stimuli, ranging from hypotonicity to heat and acidic pH. Importantly, this ion channel is constitutively expressed and capable of spontaneous activity in the absence of agonist stimulation, which suggests that it serves important physiological functions, as does its widespread dissemination throughout the body and its capacity to interact with other proteins. Not surprisingly, therefore, it has emerged more recently that TRPV4 fulfills a great number of important physiological roles and that various disease states are attributable to the absence, or abnormal functioning, of this ion channel. Here, we review the known characteristics of this ion channel's structure, localization and function, including its activators, and examine its functional importance in health and disease.
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Affiliation(s)
- John P M White
- Anaesthetics, Pain Medicine and Intensive Care Section, Department of Surgery and Cancer, Imperial College London, London, United Kingdom; Department of Anaesthetics, The Queen Elizabeth Hospital, Birmingham, United Kingdom; Academic Department of Anaesthesia and Intensive Care Medicine, School of Clinical and Experimental Medicine, University of Birmingham, Birmingham, United Kingdom; Preclinical Secondary Pharmacology, Preclinical Safety, Novartis Institute for Biomedical Research, Cambridge, Massachusetts; Laboratory of Ion Channel Research, Department of Cellular and Molecular Medicine, KU Leuven, Campus Gasthuisberg, Leuven, Belgium; and School of Medicine, Dentistry and Biomedical Science, Queen's University Belfast, Belfast, United Kingdom
| | - Mario Cibelli
- Anaesthetics, Pain Medicine and Intensive Care Section, Department of Surgery and Cancer, Imperial College London, London, United Kingdom; Department of Anaesthetics, The Queen Elizabeth Hospital, Birmingham, United Kingdom; Academic Department of Anaesthesia and Intensive Care Medicine, School of Clinical and Experimental Medicine, University of Birmingham, Birmingham, United Kingdom; Preclinical Secondary Pharmacology, Preclinical Safety, Novartis Institute for Biomedical Research, Cambridge, Massachusetts; Laboratory of Ion Channel Research, Department of Cellular and Molecular Medicine, KU Leuven, Campus Gasthuisberg, Leuven, Belgium; and School of Medicine, Dentistry and Biomedical Science, Queen's University Belfast, Belfast, United Kingdom
| | - Laszlo Urban
- Anaesthetics, Pain Medicine and Intensive Care Section, Department of Surgery and Cancer, Imperial College London, London, United Kingdom; Department of Anaesthetics, The Queen Elizabeth Hospital, Birmingham, United Kingdom; Academic Department of Anaesthesia and Intensive Care Medicine, School of Clinical and Experimental Medicine, University of Birmingham, Birmingham, United Kingdom; Preclinical Secondary Pharmacology, Preclinical Safety, Novartis Institute for Biomedical Research, Cambridge, Massachusetts; Laboratory of Ion Channel Research, Department of Cellular and Molecular Medicine, KU Leuven, Campus Gasthuisberg, Leuven, Belgium; and School of Medicine, Dentistry and Biomedical Science, Queen's University Belfast, Belfast, United Kingdom
| | - Bernd Nilius
- Anaesthetics, Pain Medicine and Intensive Care Section, Department of Surgery and Cancer, Imperial College London, London, United Kingdom; Department of Anaesthetics, The Queen Elizabeth Hospital, Birmingham, United Kingdom; Academic Department of Anaesthesia and Intensive Care Medicine, School of Clinical and Experimental Medicine, University of Birmingham, Birmingham, United Kingdom; Preclinical Secondary Pharmacology, Preclinical Safety, Novartis Institute for Biomedical Research, Cambridge, Massachusetts; Laboratory of Ion Channel Research, Department of Cellular and Molecular Medicine, KU Leuven, Campus Gasthuisberg, Leuven, Belgium; and School of Medicine, Dentistry and Biomedical Science, Queen's University Belfast, Belfast, United Kingdom
| | - J Graham McGeown
- Anaesthetics, Pain Medicine and Intensive Care Section, Department of Surgery and Cancer, Imperial College London, London, United Kingdom; Department of Anaesthetics, The Queen Elizabeth Hospital, Birmingham, United Kingdom; Academic Department of Anaesthesia and Intensive Care Medicine, School of Clinical and Experimental Medicine, University of Birmingham, Birmingham, United Kingdom; Preclinical Secondary Pharmacology, Preclinical Safety, Novartis Institute for Biomedical Research, Cambridge, Massachusetts; Laboratory of Ion Channel Research, Department of Cellular and Molecular Medicine, KU Leuven, Campus Gasthuisberg, Leuven, Belgium; and School of Medicine, Dentistry and Biomedical Science, Queen's University Belfast, Belfast, United Kingdom
| | - Istvan Nagy
- Anaesthetics, Pain Medicine and Intensive Care Section, Department of Surgery and Cancer, Imperial College London, London, United Kingdom; Department of Anaesthetics, The Queen Elizabeth Hospital, Birmingham, United Kingdom; Academic Department of Anaesthesia and Intensive Care Medicine, School of Clinical and Experimental Medicine, University of Birmingham, Birmingham, United Kingdom; Preclinical Secondary Pharmacology, Preclinical Safety, Novartis Institute for Biomedical Research, Cambridge, Massachusetts; Laboratory of Ion Channel Research, Department of Cellular and Molecular Medicine, KU Leuven, Campus Gasthuisberg, Leuven, Belgium; and School of Medicine, Dentistry and Biomedical Science, Queen's University Belfast, Belfast, United Kingdom
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27
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Understand spiciness: mechanism of TRPV1 channel activation by capsaicin. Protein Cell 2017; 8:169-177. [PMID: 28044278 PMCID: PMC5326624 DOI: 10.1007/s13238-016-0353-7] [Citation(s) in RCA: 181] [Impact Index Per Article: 25.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2016] [Accepted: 11/22/2016] [Indexed: 11/06/2022] Open
Abstract
Capsaicin in chili peppers bestows the sensation of spiciness. Since the discovery of its receptor, transient receptor potential vanilloid 1 (TRPV1) ion channel, how capsaicin activates this channel has been under extensive investigation using a variety of experimental techniques including mutagenesis, patch-clamp recording, crystallography, cryo-electron microscopy, computational docking and molecular dynamic simulation. A framework of how capsaicin binds and activates TRPV1 has started to merge: capsaicin binds to a pocket formed by the channel’s transmembrane segments, where it takes a “tail-up, head-down” configuration. Binding is mediated by both hydrogen bonds and van der Waals interactions. Upon binding, capsaicin stabilizes the open state of TRPV1 by “pull-and-contact” with the S4-S5 linker. Understanding the ligand-host interaction will greatly facilitate pharmaceutical efforts to develop novel analgesics targeting TRPV1.
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Wen H, Qin F, Zheng W. Toward elucidating the heat activation mechanism of the TRPV1 channel gating by molecular dynamics simulation. Proteins 2016; 84:1938-1949. [PMID: 27699868 DOI: 10.1002/prot.25177] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Revised: 09/03/2016] [Accepted: 09/24/2016] [Indexed: 01/01/2023]
Abstract
As a key cellular sensor, the TRPV1 cation channel undergoes a gating transition from a closed state to an open state in response to various physical and chemical stimuli including noxious heat. Despite years of study, the heat activation mechanism of TRPV1 gating remains enigmatic at the molecular level. Toward elucidating the structural and energetic basis of TRPV1 gating, we have performed molecular dynamics (MD) simulations (with cumulative simulation time of 3 μs), starting from the high-resolution closed and open structures of TRPV1 solved by cryo-electron microscopy. In the closed-state simulations at 30°C, we observed a stably closed channel constricted at the lower gate (near residue I679), while the upper gate (near residues G643 and M644) is dynamic and undergoes flickery opening/closing. In the open-state simulations at 60°C, we found higher conformational variation consistent with a large entropy increase required for the heat activation, and both the lower and upper gates are dynamic with transient opening/closing. Through ensemble-based structural analyses of the closed state versus the open state, we revealed pronounced closed-to-open conformational changes involving the membrane proximal domain (MPD) linker, the outer pore, and the TRP helix, which are accompanied by breaking/forming of a network of closed/open-state specific hydrogen bonds. By comparing the closed-state simulations at 30°C and 60°C, we observed heat-activated conformational changes in the MPD linker, the outer pore, and the TRP helix that resemble the closed-to-open conformational changes, along with partial formation of the open-state specific hydrogen bonds. Some of the residues involved in the above key hydrogen bonds were validated by previous mutational studies. Taken together, our MD simulations have offered rich structural and dynamic details beyond the static structures of TRPV1, and promising targets for future mutagenesis and functional studies of the TRPV1 channel. Proteins 2016; 84:1938-1949. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Han Wen
- Department of Physics, State University of New York at Buffalo, Buffalo, New York, 14260
| | - Feng Qin
- Department of Physiology and Biophysical Sciences, State University of New York at Buffalo, Buffalo, New York, 14260
| | - Wenjun Zheng
- Department of Physics, State University of New York at Buffalo, Buffalo, New York, 14260
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29
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Hollow Cone Electron Imaging for Single Particle 3D Reconstruction of Proteins. Sci Rep 2016; 6:27701. [PMID: 27292544 PMCID: PMC4904375 DOI: 10.1038/srep27701] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2016] [Accepted: 05/19/2016] [Indexed: 11/08/2022] Open
Abstract
The main bottlenecks for high-resolution biological imaging in electron microscopy are radiation sensitivity and low contrast. The phase contrast at low spatial frequencies can be enhanced by using a large defocus but this strongly reduces the resolution. Recently, phase plates have been developed to enhance the contrast at small defocus but electrical charging remains a problem. Single particle cryo-electron microscopy is mostly used to minimize the radiation damage and to enhance the resolution of the 3D reconstructions but it requires averaging images of a massive number of individual particles. Here we present a new route to achieve the same goals by hollow cone dark field imaging using thermal diffuse scattered electrons giving about a 4 times contrast increase as compared to bright field imaging. We demonstrate the 3D reconstruction of a stained GroEL particle can yield about 13.5 Å resolution but using a strongly reduced number of images.
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30
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Constantine M, Liew CK, Lo V, Macmillan A, Cranfield CG, Sunde M, Whan R, Graham RM, Martinac B. Heterologously-expressed and Liposome-reconstituted Human Transient Receptor Potential Melastatin 4 Channel (TRPM4) is a Functional Tetramer. Sci Rep 2016; 6:19352. [PMID: 26785754 PMCID: PMC4726259 DOI: 10.1038/srep19352] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2015] [Accepted: 12/11/2015] [Indexed: 11/24/2022] Open
Abstract
Mutation, irregular expression and sustained activation of the Transient Receptor Potential Channel, type Melastatin 4 (TRPM4), have been linked to various cardiovascular diseases. However, much remains unknown about the structure of this important ion channel. Here, we have purified a heterologously expressed TRPM4-eGFP fusion protein and investigated the oligomeric state of TRPM4-eGFP in detergent micelles using crosslinking, native gel electrophoresis, multi-angle laser light scattering and electron microscopy. Our data indicate that TRPM4 is tetrameric, like other TRP channels studied to date. Furthermore, the functionality of liposome reconstituted TRPM4-eGFP was examined using electrophysiology. Single-channel recordings from TRPM4-eGFP proteoliposomes showed inhibition of the channel using Flufenamic acid, a well-established inhibitor of TRPM4, suggesting that the channels are functional upon reconstitution. Our characterisation of the oligomeric structure of TRPM4 and the ability to reconstitute functional channels in liposomes should facilitate future studies into the structure, function and pharmacology of this therapeutically relevant channel.
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Affiliation(s)
- Maryrose Constantine
- Victor Chang Cardiac Research Institute, Lowy Packer Building, NSW 2010
- St Vincent’s Clinical School, University of New South Wales, Sydney, NSW 2010, Australia
| | - Chu Kong Liew
- Victor Chang Cardiac Research Institute, Lowy Packer Building, NSW 2010
| | - Victor Lo
- School of Medical Sciences, The Bosch Institute, The University of Sydney, NSW 2006
| | - Alex Macmillan
- Biomedical Imaging Facility, Lowy Cancer Research Centre, The University of New South Wales, Kensington, NSW 2052, Australia
| | | | - Margaret Sunde
- School of Medical Sciences, The Bosch Institute, The University of Sydney, NSW 2006
| | - Renee Whan
- Biomedical Imaging Facility, Lowy Cancer Research Centre, The University of New South Wales, Kensington, NSW 2052, Australia
| | - Robert M. Graham
- Victor Chang Cardiac Research Institute, Lowy Packer Building, NSW 2010
- St Vincent’s Clinical School, University of New South Wales, Sydney, NSW 2010, Australia
| | - Boris Martinac
- Victor Chang Cardiac Research Institute, Lowy Packer Building, NSW 2010
- St Vincent’s Clinical School, University of New South Wales, Sydney, NSW 2010, Australia
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31
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Zheng W, Qin F. A combined coarse-grained and all-atom simulation of TRPV1 channel gating and heat activation. ACTA ACUST UNITED AC 2016; 145:443-56. [PMID: 25918362 PMCID: PMC4411258 DOI: 10.1085/jgp.201411335] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
Coarse-grained modeling and all-atom molecular dynamics simulation provide insight into the mechanism for heat activation of TRPV1 gating. The transient receptor potential (TRP) channels act as key sensors of various chemical and physical stimuli in eukaryotic cells. Despite years of study, the molecular mechanisms of TRP channel activation remain unclear. To elucidate the structural, dynamic, and energetic basis of gating in TRPV1 (a founding member of the TRPV subfamily), we performed coarse-grained modeling and all-atom molecular dynamics (MD) simulation based on the recently solved high resolution structures of the open and closed form of TRPV1. Our coarse-grained normal mode analysis captures two key modes of collective motions involved in the TRPV1 gating transition, featuring a quaternary twist motion of the transmembrane domains (TMDs) relative to the intracellular domains (ICDs). Our transition pathway modeling predicts a sequence of structural movements that propagate from the ICDs to the TMDs via key interface domains (including the membrane proximal domain and the C-terminal domain), leading to sequential opening of the selectivity filter followed by the lower gate in the channel pore (confirmed by modeling conformational changes induced by the activation of ICDs). The above findings of coarse-grained modeling are robust to perturbation by lipids. Finally, our MD simulation of the ICD identifies key residues that contribute differently to the nonpolar energy of the open and closed state, and these residues are predicted to control the temperature sensitivity of TRPV1 gating. These computational predictions offer new insights to the mechanism for heat activation of TRPV1 gating, and will guide our future electrophysiology and mutagenesis studies.
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Affiliation(s)
- Wenjun Zheng
- Department of Physics and Department of Physiology and Biophysical Sciences, State University of New York at Buffalo, Buffalo, NY 14260
| | - Feng Qin
- Department of Physics and Department of Physiology and Biophysical Sciences, State University of New York at Buffalo, Buffalo, NY 14260
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32
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Kishchenko GP, Danev R, Fisher R, He J, Hsieh C, Marko M, Sui H. Effect of fringe-artifact correction on sub-tomogram averaging from Zernike phase-plate cryo-TEM. J Struct Biol 2015. [PMID: 26210582 DOI: 10.1016/j.jsb.2015.07.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Zernike phase-plate (ZPP) imaging greatly increases contrast in cryo-electron microscopy, however fringe artifacts appear in the images. A computational de-fringing method has been proposed, but it has not been widely employed, perhaps because the importance of de-fringing has not been clearly demonstrated. For testing purposes, we employed Zernike phase-plate imaging in a cryo-electron tomographic study of radial-spoke complexes attached to microtubule doublets. We found that the contrast enhancement by ZPP imaging made nonlinear denoising insensitive to the filtering parameters, such that simple low-frequency band-pass filtering made the same improvement in map quality. We employed sub-tomogram averaging, which compensates for the effect of the "missing wedge" and considerably improves map quality. We found that fringes (caused by the abrupt cut-on of the central hole in the phase plate) can lead to incorrect representation of a structure that is well-known from the literature. The expected structure was restored by amplitude scaling, as proposed in the literature. Our results show that de-fringing is an important part of image-processing for cryo-electron tomography of macromolecular complexes with ZPP imaging.
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Affiliation(s)
- Gregory P Kishchenko
- Wadsworth Center, New York State Department of Health, Albany, NY 12201, United States
| | - Radostin Danev
- Max Planck Institute of Biochemistry, Department of Molecular Structural Biology, Am Klopferspitz 18, 82152 Martinsried, Germany
| | - Rebecca Fisher
- Wadsworth Center, New York State Department of Health, Albany, NY 12201, United States
| | - Jie He
- Wadsworth Center, New York State Department of Health, Albany, NY 12201, United States
| | - Chyongere Hsieh
- Wadsworth Center, New York State Department of Health, Albany, NY 12201, United States
| | - Michael Marko
- Wadsworth Center, New York State Department of Health, Albany, NY 12201, United States
| | - Haixin Sui
- Wadsworth Center, New York State Department of Health, Albany, NY 12201, United States; Department of Biomedical Sciences, School of Public Health, University at Albany, Albany, NY 12201, United States.
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33
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Garcia-Elias A, Berna-Erro A, Rubio-Moscardo F, Pardo-Pastor C, Mrkonjić S, Sepúlveda RV, Vicente R, González-Nilo F, Valverde MA. Interaction between the Linker, Pre-S1, and TRP Domains Determines Folding, Assembly, and Trafficking of TRPV Channels. Structure 2015; 23:1404-1413. [PMID: 26146187 DOI: 10.1016/j.str.2015.05.018] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2015] [Revised: 05/14/2015] [Accepted: 05/25/2015] [Indexed: 11/26/2022]
Abstract
Functional transient receptor potential (TRP) channels result from the assembly of four subunits. Here, we show an interaction between the pre-S1, TRP, and the ankyrin repeat domain (ARD)-S1 linker domains of TRPV1 and TRPV4 that is essential for proper channel assembly. Neutralization of TRPV4 pre-S1 K462 resulted in protein retention in the ER, defective glycosylation and trafficking, and unresponsiveness to TRPV4-activating stimuli. Similar results were obtained with the equivalent mutation in TRPV1 pre-S1. Molecular dynamics simulations revealed that TRPV4-K462 generated an alternating hydrogen network with E745 (TRP box) and D425 (pre-S1 linker), and that K462Q mutation affected subunit folding. Consistently, single TRPV4-E745A or TRPV4-D425A mutations moderately affected TRPV4 biogenesis while double TRPV4-D425A/E745A mutation resumed the TRPV4-K462Q phenotype. Thus, the interaction between pre-S1, TRP, and linker domains is mandatory to generate a structural conformation that allows the contacts between adjacent subunits to promote correct assembly and trafficking to the plasma membrane.
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Affiliation(s)
- Anna Garcia-Elias
- Laboratory of Molecular Physiology and Channelopathies, Department of Experimental and Health Sciences, Universitat Pompeu Fabra, C/ Dr. Aiguader 88, Barcelona 08003, Spain
| | - Alejandro Berna-Erro
- Laboratory of Molecular Physiology and Channelopathies, Department of Experimental and Health Sciences, Universitat Pompeu Fabra, C/ Dr. Aiguader 88, Barcelona 08003, Spain
| | - Fanny Rubio-Moscardo
- Laboratory of Molecular Physiology and Channelopathies, Department of Experimental and Health Sciences, Universitat Pompeu Fabra, C/ Dr. Aiguader 88, Barcelona 08003, Spain
| | - Carlos Pardo-Pastor
- Laboratory of Molecular Physiology and Channelopathies, Department of Experimental and Health Sciences, Universitat Pompeu Fabra, C/ Dr. Aiguader 88, Barcelona 08003, Spain
| | - Sanela Mrkonjić
- Laboratory of Molecular Physiology and Channelopathies, Department of Experimental and Health Sciences, Universitat Pompeu Fabra, C/ Dr. Aiguader 88, Barcelona 08003, Spain
| | - Romina V Sepúlveda
- Universidad Andrés Bello, Center for Bioinformatics and Integrative Biology, Facultad de Ciencias Biológicas, Av. República 239, Santiago 8320000, Chile; Centro Interdisciplinario de Neurociencia de Valparaíso, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso 2366103, Chile
| | - Rubén Vicente
- Laboratory of Molecular Physiology and Channelopathies, Department of Experimental and Health Sciences, Universitat Pompeu Fabra, C/ Dr. Aiguader 88, Barcelona 08003, Spain
| | - Fernando González-Nilo
- Universidad Andrés Bello, Center for Bioinformatics and Integrative Biology, Facultad de Ciencias Biológicas, Av. República 239, Santiago 8320000, Chile; Centro Interdisciplinario de Neurociencia de Valparaíso, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso 2366103, Chile
| | - Miguel A Valverde
- Laboratory of Molecular Physiology and Channelopathies, Department of Experimental and Health Sciences, Universitat Pompeu Fabra, C/ Dr. Aiguader 88, Barcelona 08003, Spain.
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34
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Earley S, Brayden JE. Transient receptor potential channels in the vasculature. Physiol Rev 2015; 95:645-90. [PMID: 25834234 DOI: 10.1152/physrev.00026.2014] [Citation(s) in RCA: 295] [Impact Index Per Article: 32.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
The mammalian genome encodes 28 distinct members of the transient receptor potential (TRP) superfamily of cation channels, which exhibit varying degrees of selectivity for different ionic species. Multiple TRP channels are present in all cells and are involved in diverse aspects of cellular function, including sensory perception and signal transduction. Notably, TRP channels are involved in regulating vascular function and pathophysiology, the focus of this review. TRP channels in vascular smooth muscle cells participate in regulating contractility and proliferation, whereas endothelial TRP channel activity is an important contributor to endothelium-dependent vasodilation, vascular wall permeability, and angiogenesis. TRP channels are also present in perivascular sensory neurons and astrocytic endfeet proximal to cerebral arterioles, where they participate in the regulation of vascular tone. Almost all of these functions are mediated by changes in global intracellular Ca(2+) levels or subcellular Ca(2+) signaling events. In addition to directly mediating Ca(2+) entry, TRP channels influence intracellular Ca(2+) dynamics through membrane depolarization associated with the influx of cations or through receptor- or store-operated mechanisms. Dysregulation of TRP channels is associated with vascular-related pathologies, including hypertension, neointimal injury, ischemia-reperfusion injury, pulmonary edema, and neurogenic inflammation. In this review, we briefly consider general aspects of TRP channel biology and provide an in-depth discussion of the functions of TRP channels in vascular smooth muscle cells, endothelial cells, and perivascular cells under normal and pathophysiological conditions.
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Affiliation(s)
- Scott Earley
- Department of Pharmacology, University of Nevada School of Medicine, Reno, Nevada; and Department of Pharmacology, University of Vermont College of Medicine, Burlington, Vermont
| | - Joseph E Brayden
- Department of Pharmacology, University of Nevada School of Medicine, Reno, Nevada; and Department of Pharmacology, University of Vermont College of Medicine, Burlington, Vermont
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35
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Hilton JK, Rath P, Helsell CVM, Beckstein O, Van Horn WD. Understanding Thermosensitive Transient Receptor Potential Channels as Versatile Polymodal Cellular Sensors. Biochemistry 2015; 54:2401-13. [DOI: 10.1021/acs.biochem.5b00071] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- Jacob K. Hilton
- Center
for Personalized Diagnostics, Magnetic Resonance Research Center,
and Department of Chemistry and Biochemistry, Arizona State University, 551 East University Drive, PSG-106, Tempe, Arizona 85287, United States
| | - Parthasarathi Rath
- Center
for Personalized Diagnostics, Magnetic Resonance Research Center,
and Department of Chemistry and Biochemistry, Arizona State University, 551 East University Drive, PSG-106, Tempe, Arizona 85287, United States
| | - Cole V. M. Helsell
- Center
for Personalized Diagnostics, Magnetic Resonance Research Center,
and Department of Chemistry and Biochemistry, Arizona State University, 551 East University Drive, PSG-106, Tempe, Arizona 85287, United States
| | - Oliver Beckstein
- Center
for Biological Physics and Department of Physics, Arizona State University, 550 East Tyler Mall, Tempe, Arizona 85287, United States
| | - Wade D. Van Horn
- Center
for Personalized Diagnostics, Magnetic Resonance Research Center,
and Department of Chemistry and Biochemistry, Arizona State University, 551 East University Drive, PSG-106, Tempe, Arizona 85287, United States
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36
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Billen B, Brams M, Debaveye S, Remeeva A, Alpizar YA, Waelkens E, Kreir M, Brüggemann A, Talavera K, Nilius B, Voets T, Ulens C. Different ligands of the TRPV3 cation channel cause distinct conformational changes as revealed by intrinsic tryptophan fluorescence quenching. J Biol Chem 2015; 290:12964-74. [PMID: 25829496 PMCID: PMC4432310 DOI: 10.1074/jbc.m114.628925] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2014] [Indexed: 11/26/2022] Open
Abstract
TRPV3 is a thermosensitive ion channel primarily expressed in epithelial tissues of the skin, nose, and tongue. The channel has been implicated in environmental thermosensation, hyperalgesia in inflamed tissues, skin sensitization, and hair growth. Although transient receptor potential (TRP) channel research has vastly increased our understanding of the physiological mechanisms of nociception and thermosensation, the molecular mechanics of these ion channels are still largely elusive. In order to better comprehend the functional properties and the mechanism of action in TRP channels, high-resolution three-dimensional structures are indispensable, because they will yield the necessary insights into architectural intimacies at the atomic level. However, structural studies of membrane proteins are currently hampered by difficulties in protein purification and in establishing suitable crystallization conditions. In this report, we present a novel protocol for the purification of membrane proteins, which takes advantage of a C-terminal GFP fusion. Using this protocol, we purified human TRPV3. We show that the purified protein is a fully functional ion channel with properties akin to the native channel using planar patch clamp on reconstituted channels and intrinsic tryptophan fluorescence spectroscopy. Using intrinsic tryptophan fluorescence spectroscopy, we reveal clear distinctions in the molecular interaction of different ligands with the channel. Altogether, this study provides powerful tools to broaden our understanding of ligand interaction with TRPV channels, and the availability of purified human TRPV3 opens up perspectives for further structural and functional studies.
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Affiliation(s)
- Bert Billen
- From the Laboratory of Structural Neurobiology and TRP Research Platform Leuven (TRPLe), Department of Cellular and Molecular Medicine, University of Leuven, Herestraat 49 Box 601, 3000 Leuven, Belgium,
| | - Marijke Brams
- From the Laboratory of Structural Neurobiology and TRP Research Platform Leuven (TRPLe), Department of Cellular and Molecular Medicine, University of Leuven, Herestraat 49 Box 601, 3000 Leuven, Belgium
| | - Sarah Debaveye
- From the Laboratory of Structural Neurobiology and TRP Research Platform Leuven (TRPLe), Department of Cellular and Molecular Medicine, University of Leuven, Herestraat 49 Box 601, 3000 Leuven, Belgium
| | - Alina Remeeva
- From the Laboratory of Structural Neurobiology and TRP Research Platform Leuven (TRPLe), Department of Cellular and Molecular Medicine, University of Leuven, Herestraat 49 Box 601, 3000 Leuven, Belgium
| | - Yeranddy A Alpizar
- the Laboratory of Ion Channel Research and TRP Research Platform Leuven (TRPLe), Department of Cellular and Molecular Medicine, University of Leuven, Herestraat 49 Box 802, 3000 Leuven, Belgium
| | - Etienne Waelkens
- the Laboratory of Protein Phosphorylation and Proteomics, Department of Cellular and Molecular Medicine, University of Leuven, Herestraat 49 Box 901, 3000 Leuven, Belgium, and
| | - Mohamed Kreir
- Nanion Technologies GmbH, Gabrielenstrasse 9, D-80636 Munich, Germany
| | - Andrea Brüggemann
- Nanion Technologies GmbH, Gabrielenstrasse 9, D-80636 Munich, Germany
| | - Karel Talavera
- the Laboratory of Ion Channel Research and TRP Research Platform Leuven (TRPLe), Department of Cellular and Molecular Medicine, University of Leuven, Herestraat 49 Box 802, 3000 Leuven, Belgium
| | - Bernd Nilius
- the Laboratory of Ion Channel Research and TRP Research Platform Leuven (TRPLe), Department of Cellular and Molecular Medicine, University of Leuven, Herestraat 49 Box 802, 3000 Leuven, Belgium
| | - Thomas Voets
- the Laboratory of Ion Channel Research and TRP Research Platform Leuven (TRPLe), Department of Cellular and Molecular Medicine, University of Leuven, Herestraat 49 Box 802, 3000 Leuven, Belgium
| | - Chris Ulens
- From the Laboratory of Structural Neurobiology and TRP Research Platform Leuven (TRPLe), Department of Cellular and Molecular Medicine, University of Leuven, Herestraat 49 Box 601, 3000 Leuven, Belgium
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Taberner FJ, Fernández-Ballester G, Fernández-Carvajal A, Ferrer-Montiel A. TRP channels interaction with lipids and its implications in disease. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2015; 1848:1818-27. [PMID: 25838124 DOI: 10.1016/j.bbamem.2015.03.022] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2014] [Revised: 03/21/2015] [Accepted: 03/23/2015] [Indexed: 01/21/2023]
Abstract
Transient receptor potential (TRP) proteins are a family of ion channels central for sensory signaling. These receptors and, in particular, those involved in thermal sensing are also involved in pain signaling. Noteworthy, thermosensory receptors are polymodal ion channels that respond to both physical and chemical stimuli, thus integrating different environmental clues. In addition, their activity is modulated by algesic agents and lipidergic substances that are primarily released in pathological states. Lipids and lipid-like molecules have been found that can directly activate some thermosensory channels or modulate their activity by either potentiating or inhibiting it. To date, more than 50 endogenous lipids that can regulate TRP channel activity in sensory neurons have been described, thus representing the majority of known endogenous TRP channel modulators. Lipid modulators of TRP channels comprise lipids from a variety of metabolic pathways, including metabolites of the cyclooxygenase, lipoxygenase and cytochrome-P450 pathways, phospholipids and lysophospholipids. Therefore, TRP-channels are able to integrate and interpret incoming signals from the different metabolic lipid pathways. Taken together, the large number of lipids that can activate, sensitize or inhibit neuronal TRP-channels highlights the pivotal role of these molecules in sensory biology as well as in pain transduction and perception. This article is part of a Special Issue entitled: Lipid-protein interactions. Guest Editors: Amitabha Chattopadhyay and Jean-Marie Ruysschaert.
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Affiliation(s)
- Francisco J Taberner
- Instituto de Biología Molecular y Celular, Universidad Miguel Hernández, Alicante, Spain
| | | | | | - Antonio Ferrer-Montiel
- Instituto de Biología Molecular y Celular, Universidad Miguel Hernández, Alicante, Spain.
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Baker MR, Fan G, Serysheva II. Single-Particle Cryo-EM of the Ryanodine Receptor Channel in an Aqueous Environment. Eur J Transl Myol 2015; 25:4803. [PMID: 26913144 PMCID: PMC4748972 DOI: 10.4081/ejtm.2015.4803] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Revised: 12/22/2014] [Accepted: 12/31/2014] [Indexed: 12/31/2022] Open
Abstract
Ryanodine receptors (RyRs) are tetrameric ligand-gated Ca2+ release channels that are responsible for the increase of cytosolic Ca2+ concentration leading to muscle contraction. Our current understanding of RyR channel gating and regulation is greatly limited due to the lack of a high-resolution structure of the channel protein. The enormous size and unwieldy shape of Ca2+ release channels make X-ray or NMR methods difficult to apply for high-resolution structural analysis of the full-length functional channel. Single-particle electron cryo-microscopy (cryo-EM) is one of the only effective techniques for the study of such a large integral membrane protein and its molecular interactions. Despite recent developments in cryo-EM technologies and break-through single-particle cryo-EM studies of ion channels, cryospecimen preparation, particularly the presence of detergent in the buffer, remains the main impediment to obtaining atomic-resolution structures of ion channels and a multitude of other integral membrane protein complexes. In this review we will discuss properties of several detergents that have been successfully utilized in cryo-EM studies of ion channels and the emergence of the detergent alternative amphipol to stabilize ion channels for structure-function characterization. Future structural studies of challenging specimen like ion channels are likely to be facilitated by cryo-EM amenable detergents or alternative surfactants.
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Affiliation(s)
- Mariah R Baker
- Department of Biochemistry and Molecular Biology, The University of Texas Medical School at Houston, 6431 Fannin Street, Houston, TX 77030, USA
| | - Guizhen Fan
- Department of Biochemistry and Molecular Biology, The University of Texas Medical School at Houston, 6431 Fannin Street, Houston, TX 77030, USA
| | - Irina I Serysheva
- Department of Biochemistry and Molecular Biology, The University of Texas Medical School at Houston, 6431 Fannin Street, Houston, TX 77030, USA
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Veldhuis NA, Poole DP, Grace M, McIntyre P, Bunnett NW. The G Protein–Coupled Receptor–Transient Receptor Potential Channel Axis: Molecular Insights for Targeting Disorders of Sensation and Inflammation. Pharmacol Rev 2014; 67:36-73. [DOI: 10.1124/pr.114.009555] [Citation(s) in RCA: 114] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
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Goldenberg NM, Ravindran K, Kuebler WM. TRPV4: physiological role and therapeutic potential in respiratory diseases. Naunyn Schmiedebergs Arch Pharmacol 2014; 388:421-36. [PMID: 25342095 DOI: 10.1007/s00210-014-1058-1] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2014] [Accepted: 10/10/2014] [Indexed: 01/11/2023]
Abstract
Members of the family of transient receptor potential (TRP) channels have been implicated in the pathophysiology of a host of lung diseases. The role of these multimodal cation channels in lung homeostasis is thought to stem from their ability to respond to changes in mechanical stimuli (i.e., shear and stretch), as well as to various protein and lipid mediators. The vanilloid subfamily member, TRPV4, which is highly expressed in the majority of lung cell types, is well positioned for critical involvement in several pulmonary conditions, including edema formation, control of pulmonary vascular tone, and the lung response to local or systemic inflammatory insults. In recent years, several pharmacological inhibitors of TRPV4 have been developed, and the current generation of compounds possess high affinity and specificity for TRPV4. As such, we have now entered a time where the therapeutic potential of TRPV4 inhibitors can be systematically examined in a variety of lung diseases. Due to this fact, this review seeks to describe the current state of the art with respect to the role of TRPV4 in pulmonary homeostasis and disease, and to highlight the current and future roles of TRPV4 inhibitors in disease treatment. We will first focus on genera aspects of TRPV4 structure and function, and then will discuss known roles for TRPV4 in pulmonary diseases, including pulmonary edema formation, pulmonary hypertension, and acute lung injury. Finally, both promising aspects and potential pitfalls of the clinical use of TRPV4 inhibitors will be examined.
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Affiliation(s)
- Neil M Goldenberg
- Department of Anesthesia, University of Toronto, Toronto, ON, Canada
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Agosto MA, Zhang Z, He F, Anastassov IA, Wright SJ, McGehee J, Wensel TG. Oligomeric state of purified transient receptor potential melastatin-1 (TRPM1), a protein essential for dim light vision. J Biol Chem 2014; 289:27019-27033. [PMID: 25112866 PMCID: PMC4175340 DOI: 10.1074/jbc.m114.593780] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2014] [Revised: 08/03/2014] [Indexed: 11/06/2022] Open
Abstract
Transient receptor potential melastatin-1 (TRPM1) is essential for the light-induced depolarization of retinal ON bipolar cells. TRPM1 likely forms a multimeric channel complex, although almost nothing is known about the structure or subunit composition of channels formed by TRPM1 or any of its close relatives. Recombinant TRPM1 was robustly expressed in insect cells, but only a small fraction was localized to the plasma membrane. Similar intracellular localization was observed when TRPM1 was heterologously expressed in mammalian cells. TRPM1 was affinity-purified from Sf9 cells and complexed with amphipol, followed by detergent removal. In blue native gels and size exclusion chromatography, TRPM1 migrated with a mobility consistent with detergent- or amphipol-bound dimers. Cross-linking experiments were also consistent with a dimeric subunit stoichiometry, and cryoelectron microscopy and single particle analysis without symmetry imposition yielded a model with approximate 2-fold symmetrical features. Finally, electron microscopy of TRPM1-antibody complexes revealed a large particle that can accommodate TRPM1 and two antibody molecules. Taken together, these data indicate that purified TRPM1 is mostly dimeric. The three-dimensional structure of TRPM1 dimers is characterized by a small putative transmembrane domain and a larger domain with a hollow cavity. Blue native gels of solubilized mouse retina indicate that TRPM1 is present in two distinct complexes: one similar in size to the recombinant protein and one much larger. Because dimers are likely not functional ion channels, these results suggest that additional partner subunits participate in forming the transduction channel required for dim light vision and the ON pathway.
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Affiliation(s)
- Melina A Agosto
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, Texas 77030
| | - Zhixian Zhang
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, Texas 77030
| | - Feng He
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, Texas 77030
| | - Ivan A Anastassov
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, Texas 77030
| | - Sara J Wright
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, Texas 77030
| | - Jennifer McGehee
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, Texas 77030
| | - Theodore G Wensel
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, Texas 77030.
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TRPV4 channel activity is modulated by direct interaction of the ankyrin domain to PI(4,5)P₂. Nat Commun 2014; 5:4994. [PMID: 25256292 DOI: 10.1038/ncomms5994] [Citation(s) in RCA: 89] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2014] [Accepted: 08/15/2014] [Indexed: 11/09/2022] Open
Abstract
Mutations in the ankyrin repeat domain (ARD) of TRPV4 are responsible for several channelopathies, including Charcot-Marie-Tooth disease type 2C and congenital distal and scapuloperoneal spinal muscular atrophy. However, the molecular pathogenesis mediated by these mutations remains elusive, mainly due to limited understanding of the TRPV4 ARD function. Here we show that phosphoinositide binding to the TRPV4 ARD leads to suppression of the channel activity. Among the phosphoinositides, phosphatidylinositol-4,5-bisphosphate (PI(4,5)P2) most potently binds to the TRPV4 ARD. The crystal structure of the TRPV4 ARD in complex with inositol-1,4,5-trisphosphate, the head-group of PI(4,5)P2, and the molecular-dynamics simulations revealed the PI(4,5)P2-binding amino-acid residues. The TRPV4 channel activities were increased by titration or hydrolysis of membrane PI(4,5)P2. Notably, disease-associated TRPV4 mutations that cause a gain-of-function phenotype abolished PI(4,5)P2 binding and PI(4,5)P2 sensitivity. These findings identify TRPV4 ARD as a lipid-binding domain in which interactions with PI(4,5)P2 normalize the channel activity in TRPV4.
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Shigematsu H, Iida K, Nakano M, Chaudhuri P, Iida H, Nagayama K. Structural characterization of the mechanosensitive channel candidate MCA2 from Arabidopsis thaliana. PLoS One 2014; 9:e87724. [PMID: 24475319 PMCID: PMC3903776 DOI: 10.1371/journal.pone.0087724] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2013] [Accepted: 12/30/2013] [Indexed: 11/19/2022] Open
Abstract
Mechanosensing in plants is thought to be governed by sensory complexes containing a Ca²⁺-permeable, mechanosensitive channel. The plasma membrane protein MCA1 and its paralog MCA2 from Arabidopsis thaliana are involved in mechanical stress-induced Ca²⁺ influx and are thus considered as candidates for such channels or their regulators. Both MCA1 and MCA2 were functionally expressed in Sf9 cells using a baculovirus system in order to elucidate their molecular natures. Because of the abundance of protein in these cells, MCA2 was chosen for purification. Purified MCA2 in a detergent-solubilized state formed a tetramer, which was confirmed by chemical cross-linking. Single-particle analysis of cryo-electron microscope images was performed to depict the overall shape of the purified protein. The three-dimensional structure of MCA2 was reconstructed at a resolution of 26 Å from 5,500 particles and appears to comprise a small transmembrane region and large cytoplasmic region.
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Affiliation(s)
- Hideki Shigematsu
- Okazaki Institute for Integrative Bioscience, National Institutes of Natural Sciences, Okazaki, Aichi, Japan
| | - Kazuko Iida
- Biomembrane Laboratory, Tokyo Metropolitan Institute of Medical Science, Setagaya-ku, Tokyo, Japan
| | - Masataka Nakano
- Department of Biology, Tokyo Gakugei University, Koganei, Tokyo, Japan
| | - Pratima Chaudhuri
- Okazaki Institute for Integrative Bioscience, National Institutes of Natural Sciences, Okazaki, Aichi, Japan
| | - Hidetoshi Iida
- Okazaki Institute for Integrative Bioscience, National Institutes of Natural Sciences, Okazaki, Aichi, Japan
- Department of Biology, Tokyo Gakugei University, Koganei, Tokyo, Japan
| | - Kuniaki Nagayama
- Okazaki Institute for Integrative Bioscience, National Institutes of Natural Sciences, Okazaki, Aichi, Japan
- National Institute for Physiological Sciences, National Institutes of Natural Sciences, Okazaki, Aichi, Japan
- Department of Physiological Sciences, Graduate University for Advanced Studies, Okazaki, Aichi, Japan
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Abstract
Membrane proteins remain challenging targets for structural biologists, despite recent technical developments regarding sample preparation and structure determination. We review recent progress towards a structural understanding of TRP channels and the techniques used to that end. We discuss available low-resolution structures from electron microscopy (EM), X-ray crystallography, and nuclear magnetic resonance (NMR) and review the resulting insights into TRP channel function for various subfamily members. The recent high-resolution structure of TRPV1 is discussed in more detail in Chapter 11. We also consider the opportunities and challenges of using the accumulating structural information on TRPs and homologous proteins for deducing full-length structures of different TRP channel subfamilies, such as building homology models. Finally, we close by summarizing the outlook of the "holy grail" of understanding in atomic detail the diverse functions of TRP channels.
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45
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Cohen MR, Moiseenkova-Bell VY. Structure of thermally activated TRP channels. CURRENT TOPICS IN MEMBRANES 2014; 74:181-211. [PMID: 25366237 DOI: 10.1016/b978-0-12-800181-3.00007-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Temperature sensation is important for adaptation and survival of organisms. While temperature has the potential to affect all biological macromolecules, organisms have evolved specific thermosensitive molecular detectors that are able to transduce temperature changes into physiologically relevant signals. Among these thermosensors are ion channels from the transient receptor potential (TRP) family. Prime candidates include TRPV1-4, TRPA1, and TRPM8 (the so-called "thermoTRP" channels), which are expressed in sensory neurons and gated at specific temperatures. Electrophysiological and thermodynamic approaches have been employed to determine the nature by which thermoTRPs detect temperature and couple temperature changes to channel gating. To further understand how thermoTRPs sense temperature, high-resolution structures of full-length thermoTRPs channels will be required. Here, we will discuss current progress in unraveling the structures of thermoTRP channels.
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Affiliation(s)
- Matthew R Cohen
- Department of Pharmacology, Case Western Reserve University School of Medicine, Cleveland, OH, USA; Department of Physiology & Biophysics, Case Western Reserve University School of Medicine, Cleveland, OH, USA
| | - Vera Y Moiseenkova-Bell
- Department of Pharmacology, Case Western Reserve University School of Medicine, Cleveland, OH, USA; Department of Physiology & Biophysics, Case Western Reserve University School of Medicine, Cleveland, OH, USA
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46
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Baez D, Raddatz N, Ferreira G, Gonzalez C, Latorre R. Gating of thermally activated channels. CURRENT TOPICS IN MEMBRANES 2014; 74:51-87. [PMID: 25366233 DOI: 10.1016/b978-0-12-800181-3.00003-8] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
A class of ion channels that belongs to the transient receptor potential (TRP) superfamily and is present in specialized neurons that project to the skin has evolved as temperature detectors. These channels are classified into subfamilies, namely canonical (TRPC), melastatin (TRPM), ankyrin (TRPA), and vanilloid (TRPV). Some of these channels are activated by heat (TRPM2/4/5, TRPV1-4), while others by cold (TRPA1, TRPC5, and TRPM8). The general structure of these channels is closely related to that of the voltage-dependent K(+) channels, with their subunits containing six transmembrane segments that form tetramers. Thermal TRP channels are polymodal receptors. That is, they can be activated by temperature, voltage, pH, lipids, and agonists. The high temperature sensitivity in these thermal TRP channels is due to a large enthalpy change (∼100 kcal/mol), which is about five times the enthalpy change in voltage-dependent gating. The characterization of the macroscopic currents and single-channel analysis demonstrated that gating by temperature is complex and best described by branched or allosteric models containing several closed and open states. The identification of molecular determinants of temperature sensitivity in TRPV1, TRPA1, and TRPV3 strongly suggest that thermal sensitivity arises from a specific protein domain.
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Affiliation(s)
- David Baez
- Centro Interdisciplinario de Neurociencia de Valparaíso, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
| | - Natalia Raddatz
- Centro Interdisciplinario de Neurociencia de Valparaíso, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile; Centre for Plant Biotechnology and Genomics, Universidad Politécnica de Madrid, Pozuelo de Alarcón (Madrid), Spain
| | - Gonzalo Ferreira
- Laboratorio de Canales Iónicos, Departamento de Biofísica, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay
| | - Carlos Gonzalez
- Centro Interdisciplinario de Neurociencia de Valparaíso, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
| | - Ramon Latorre
- Centro Interdisciplinario de Neurociencia de Valparaíso, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
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Liao M, Cao E, Julius D, Cheng Y. Structure of the TRPV1 ion channel determined by electron cryo-microscopy. Nature 2013; 504:107-12. [PMID: 24305160 PMCID: PMC4078027 DOI: 10.1038/nature12822] [Citation(s) in RCA: 1205] [Impact Index Per Article: 109.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2013] [Accepted: 10/30/2013] [Indexed: 02/07/2023]
Abstract
Transient receptor potential (TRP) channels are sensors for a wide range of cellular and environmental signals, but elucidating how these channels respond to physical and chemical stimuli has been hampered by a lack of detailed structural information. Here we exploit advances in electron cryo-microscopy to determine the structure of a mammalian TRP channel, TRPV1, at 3.4 Å resolution, breaking the side-chain resolution barrier for membrane proteins without crystallization. Like voltage-gated channels, TRPV1 exhibits four-fold symmetry around a central ion pathway formed by transmembrane segments 5-6 (S5-S6) and the intervening pore loop, which is flanked by S1-S4 voltage-sensor-like domains. TRPV1 has a wide extracellular 'mouth' with a short selectivity filter. The conserved 'TRP domain' interacts with the S4-S5 linker, consistent with its contribution to allosteric modulation. Subunit organization is facilitated by interactions among cytoplasmic domains, including amino-terminal ankyrin repeats. These observations provide a structural blueprint for understanding unique aspects of TRP channel function.
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Affiliation(s)
- Maofu Liao
- 1] Keck Advanced Microscopy Laboratory, Department of Biochemistry and Biophysics, University of California, San Francisco, California 94158-2517, USA [2]
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Huynh KW, Cohen MR, Chakrapani S, Holdaway HA, Stewart PL, Moiseenkova-Bell VY. Structural insight into the assembly of TRPV channels. Structure 2013; 22:260-8. [PMID: 24373766 DOI: 10.1016/j.str.2013.11.008] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2013] [Revised: 11/01/2013] [Accepted: 11/21/2013] [Indexed: 11/25/2022]
Abstract
Transient receptor potential (TRP) proteins are a large family of polymodal nonselective cation channels. The TRP vanilloid (TRPV) subfamily consists of six homologous members with diverse functions. TRPV1-TRPV4 are nonselective cation channels proposed to play a role in nociception, while TRPV5 and TRPV6 are involved in epithelial Ca²⁺ homeostasis. Here we present the cryo-electron microscopy (cryo-EM) structure of functional, full-length TRPV2 at 13.6 Å resolution. The map reveals that the TRPV2 cytoplasmic domain displays a 4-fold petal-like shape in which high-resolution N-terminal ankyrin repeat domain (ARD) structures can be unambiguously fitted. Fitting of the available ARD structures for other TRPV subfamily members into the TRPV2 EM map suggests that TRPV subfamily members have highly homologous structural topologies. These results allowed us to postulate a structural explanation for the functional diversity among TRPV channels and their differential regulation by proteins and ligands.
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Affiliation(s)
- Kevin W Huynh
- Department of Pharmacology, Case Western Reserve University School of Medicine, 10900 Euclid Avenue, Cleveland, OH 44106, USA; Cleveland Center for Membrane and Structural Biology, Case Western Reserve University School of Medicine, 10900 Euclid Avenue, Cleveland, OH 44106, USA
| | - Matthew R Cohen
- Deparment of Physiology and Biophysics, Case Western Reserve University School of Medicine, 10900 Euclid Avenue, Cleveland, OH 44106, USA; Cleveland Center for Membrane and Structural Biology, Case Western Reserve University School of Medicine, 10900 Euclid Avenue, Cleveland, OH 44106, USA
| | - Sudha Chakrapani
- Deparment of Physiology and Biophysics, Case Western Reserve University School of Medicine, 10900 Euclid Avenue, Cleveland, OH 44106, USA; Cleveland Center for Membrane and Structural Biology, Case Western Reserve University School of Medicine, 10900 Euclid Avenue, Cleveland, OH 44106, USA
| | - Heather A Holdaway
- Department of Pharmacology, Case Western Reserve University School of Medicine, 10900 Euclid Avenue, Cleveland, OH 44106, USA; Cleveland Center for Membrane and Structural Biology, Case Western Reserve University School of Medicine, 10900 Euclid Avenue, Cleveland, OH 44106, USA
| | - Phoebe L Stewart
- Department of Pharmacology, Case Western Reserve University School of Medicine, 10900 Euclid Avenue, Cleveland, OH 44106, USA; Cleveland Center for Membrane and Structural Biology, Case Western Reserve University School of Medicine, 10900 Euclid Avenue, Cleveland, OH 44106, USA
| | - Vera Y Moiseenkova-Bell
- Department of Pharmacology, Case Western Reserve University School of Medicine, 10900 Euclid Avenue, Cleveland, OH 44106, USA; Deparment of Physiology and Biophysics, Case Western Reserve University School of Medicine, 10900 Euclid Avenue, Cleveland, OH 44106, USA; Cleveland Center for Membrane and Structural Biology, Case Western Reserve University School of Medicine, 10900 Euclid Avenue, Cleveland, OH 44106, USA.
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49
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Expression, purification, and projection structure by single particle electron microscopy of functional human TRPM4 heterologously expressed in Xenopus laevis oocytes. Protein Expr Purif 2013; 95:169-76. [PMID: 24333049 DOI: 10.1016/j.pep.2013.11.017] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2013] [Revised: 11/28/2013] [Accepted: 11/30/2013] [Indexed: 01/23/2023]
Abstract
Despite efforts implicating the cationic channel transient receptor potential melastatin member 4 (TRPM4) to cardiac, nervous, and immunological pathologies, little is known about its structure and function. In this study, we optimized the requirements for purification and extraction of functional human TRPM4 protein and investigated its supra-molecular assembly. We selected the Xenopus laevis oocyte expression system because it lacks endogenous TRPM4 expression, it is known to overexpress functional human membrane channels, can be used for structure-function analysis within the same system, and is easily scaled to improve yield and develop moderate throughput capabilities through the use of robotics. Negative-stain electron microscopy (EM) revealed various sized low-resolution particles. Single particle analysis identified the majority of the projections represented the monomeric form with additional oligomeric structures potentially characterized as tetramers. Two-electrode voltage clamp electrophysiology demonstrated that human TRPM4 is functionally expressed at the oocyte plasma membrane. This study opens the door for medium-throughput screening and structure-function determination of this important therapeutically relevant target.
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50
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Abstract
Transient receptor potential (TRP) channels are cellular sensors for a wide spectrum of physical and chemical stimuli. They are involved in the formation of sight, hearing, touch, smell, taste, temperature, and pain sensation. TRP channels also play fundamental roles in cell signaling and allow the host cell to respond to benign or harmful environmental changes. As TRP channel activation is controlled by very diverse processes and, in many cases, exhibits complex polymodal properties, understanding how each TRP channel responds to its unique forms of activation energy is both crucial and challenging. The past two decades witnessed significant advances in understanding the molecular mechanisms that underlie TRP channels activation. This review focuses on our current understanding of the molecular determinants for TRP channel activation.
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Affiliation(s)
- Jie Zheng
- Department of Physiology and Membrane Biology, University of California School of Medicine, Davis, California, USA.
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