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Eliav T, Benoliel R, Korczeniewska OA. Post-Traumatic Trigeminal Neuropathy: Neurobiology and Pathophysiology. BIOLOGY 2024; 13:167. [PMID: 38534437 DOI: 10.3390/biology13030167] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2023] [Revised: 02/23/2024] [Accepted: 02/26/2024] [Indexed: 03/28/2024]
Abstract
Painful traumatic trigeminal neuropathy (PTTN) is a chronic neuropathic pain that may develop following injury to the trigeminal nerve. Etiologies include cranio-orofacial trauma that may result from dental, surgical, or anesthetic procedures or physical trauma, such as a motor vehicle accident. Following nerve injury, there are various mechanisms, including peripheral and central, as well as phenotypic changes and genetic predispositions that may contribute to the development of neuropathic pain. In this article, we review current literature pertaining to the cellular processes that occur following traumatic damage to the trigeminal nerve, also called cranial nerve V, that results in chronic neuropathic pain. We examine the neurobiology and pathophysiology based mostly on pre-clinical animal models of neuropathic/trigeminal pain.
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Affiliation(s)
- Tal Eliav
- Medical School for International Health, Faculty of Health Sciences, Ben Gurion University of the Negev, Beer Sheva 8410501, Israel
| | - Rafael Benoliel
- Center for Orofacial Pain and Temporomandibular Disorders, Department of Diagnostic Sciences, Rutgers School of Dental Medicine, Rutgers, The State University of New Jersey, Room D-837, 110 Bergen Street, Newark, NJ 07101, USA
| | - Olga A Korczeniewska
- Center for Orofacial Pain and Temporomandibular Disorders, Department of Diagnostic Sciences, Rutgers School of Dental Medicine, Rutgers, The State University of New Jersey, Room D-837, 110 Bergen Street, Newark, NJ 07101, USA
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2
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Yang B, Yu N. Traditional Chinese medicine alleviating neuropathic pain targeting purinergic receptor P2 in purinergic signaling: A review. Brain Res Bull 2023; 204:110800. [PMID: 37913850 DOI: 10.1016/j.brainresbull.2023.110800] [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: 09/18/2023] [Revised: 10/25/2023] [Accepted: 10/27/2023] [Indexed: 11/03/2023]
Abstract
Past studies have suggested that Chinese herbal may alleviate neuropathic pain, and the mechanism might target the inhibition of purinergic receptor P2. This review discusses whether traditional Chinese medicine target P2 receptors in neuropathic pain and its mechanism in order to provide references for future clinical drug development. The related literatures were searched from Pubmed, Embase, Sinomed, and CNKI databases before June 2023. The search terms included"neuropathic pain", "purinergic receptor P2", "P2", "traditional Chinese medicine", "Chinese herbal medicine", and "herb". We described the traditional Chinese medicine alleviating neuropathic pain via purinergic receptor P2 signaling pathway including P2X2/3 R, P2X3R, P2X4R, P2X7R, P2Y1R. Inhibition of activating glial cells, changing synaptic transmission, increasing painful postsynaptic potential, and activating inflammatory signaling pathways maybe the mechanism. Purine receptor P2 can mediate the occurrence of neuropathic pain. And many of traditional Chinese medicines can target P2 receptors to relieve neuropathic pain, which provides reasonable evidences for the future development of drugs. Also, the safety and efficacy and mechanism need more in-depth experimental research.
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Affiliation(s)
- Bo Yang
- Department of Center for Psychosomatic Medicine,Sichuan Provincial Center for Mental Health,Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu 611135, China
| | - Nengwei Yu
- Department of Neurology, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu 610072, China.
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3
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P2X 4 deficiency reduces atherosclerosis and plaque inflammation in mice. Sci Rep 2022; 12:2801. [PMID: 35181718 PMCID: PMC8857235 DOI: 10.1038/s41598-022-06706-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Accepted: 01/19/2022] [Indexed: 12/25/2022] Open
Abstract
Extracellular adenosine-5′-triphosphate (ATP) acts as an import signaling molecule mediating inflammation via purinergic P2 receptors. ATP binds to the purinergic receptor P2X4 and promotes inflammation via increased expression of pro-inflammatory cytokines. Because of the central role of inflammation, we assumed a functional contribution of the ATP-P2X4-axis in atherosclerosis. Expression of P2X4 was increased in atherosclerotic aortic arches from low-density lipoprotein receptor-deficient mice being fed a high cholesterol diet as assessed by real-time polymerase chain reaction and immunohistochemistry. To investigate the functional role of P2X4 in atherosclerosis, P2X4-deficient mice were crossed with low-density lipoprotein receptor-deficient mice and fed high cholesterol diet. After 16 weeks, P2X4-deficient mice developed smaller atherosclerotic lesions compared to P2X4-competent mice. Furthermore, intravital microscopy showed reduced ATP-induced leukocyte rolling at the vessel wall in P2X4-deficient mice. Mechanistically, we found a reduced RNA expression of CC chemokine ligand 2 (CCL-2), C-X-C motif chemokine-1 (CXCL-1), C-X-C motif chemokine-2 (CXCL-2), Interleukin-6 (IL-6) and tumor necrosis factor α (TNFα) as well as a decreased nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3)-inflammasome priming in atherosclerotic plaques from P2X4-deficient mice. Moreover, bone marrow derived macrophages isolated from P2X4-deficient mice revealed a reduced ATP-mediated release of CCL-2, CC chemokine ligand 5 (CCL-5), Interleukin-1β (IL-1β) and IL-6. Additionally, P2X4-deficient mice shared a lower proportion of pro-inflammatory Ly6Chigh monocytes and a higher proportion of anti-inflammatory Ly6Clow monocytes, and expressend less endothelial VCAM-1. Finally, increased P2X4 expression in human atherosclerotic lesions from carotid endarterectomy was found, indicating the importance of potential implementations of this study’s findings for human atherosclerosis. Collectively, P2X4 deficiency reduced experimental atherosclerosis, plaque inflammation and inflammasome priming, pointing to P2X4 as a potential therapeutic target in the fight against atherosclerosis.
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4
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Folding RNA-Protein Complex into Designed Nanostructures. Methods Mol Biol 2021. [PMID: 34086284 DOI: 10.1007/978-1-0716-1499-0_16] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
Abstract
RNA-protein (RNP) complexes are promising biomaterials for the fields of nanotechnology and synthetic biology. Protein-responsive RNA sequences (RNP motifs) can be integrated into various RNAs, such as messenger RNA, short-hairpin RNA, and synthetic RNA nanoobjects for a variety of purposes. Direct observation of RNP interaction in solution at high resolution is important in the design and construction of RNP-mediated nanostructures. Here we describe a method to construct and visualize RNP nanostructures that precisely arrange a target protein on the RNA scaffold with nanometer scale. High-speed AFM (HS-AFM) images of RNP nanostructures show that the folding of RNP complexes of defined sizes can be directly visualized at single RNP resolution in solution.
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Heath GR, Lin YC, Matin TR, Scheuring S. Structural dynamics of channels and transporters by high-speed atomic force microscopy. Methods Enzymol 2021; 652:127-159. [PMID: 34059280 DOI: 10.1016/bs.mie.2021.03.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Channels and transporters are vital for transmembrane transport of ions and solutes, and also of larger compounds such as lipids and macromolecules. Therefore, they are crucial in many biological processes such as sensing, signal transduction, and the regulation of the distribution of molecules. Dysfunctions of these membrane proteins are associated to numerous diseases, and their interaction with drugs is critical in medicine. Understanding the behavior of channels and transporters requires structural and dynamic information to decipher the molecular mechanisms underlying their function. High-Speed Atomic Force Microscopy (HS-AFM) now allows the study of single transmembrane channels and transporters in action under physiological conditions, i.e., at ambient temperature and pressure, in physiological buffer and in a membrane, and in a most direct, label-free manner. In this chapter, we discuss the HS-AFM sample preparation, application, and data analysis protocols to study the structural and conformational dynamics of membrane-embedded channels and transporters.
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Affiliation(s)
- George R Heath
- School of Physics and Astronomy, University of Leeds, Leeds, United Kingdom
| | - Yi-Chih Lin
- Weill Cornell Medicine, Department of Anesthesiology, New York, NY, United States
| | - Tina R Matin
- Weill Cornell Medicine, Department of Anesthesiology, New York, NY, United States
| | - Simon Scheuring
- Weill Cornell Medicine, Department of Anesthesiology, New York, NY, United States; Weill Cornell Medicine, Department of Physiology and Biophysics, New York, NY, United States.
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Cui Y, Zhao Y, Lu Y, Su X, Chen Y, Shen Y, Lin J, Li X. In vivo single-particle tracking of the aquaporin AtPIP2;1 in stomata reveals cell type-specific dynamics. PLANT PHYSIOLOGY 2021; 185:1666-1681. [PMID: 33569600 PMCID: PMC8133650 DOI: 10.1093/plphys/kiab007] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Accepted: 12/23/2020] [Indexed: 05/20/2023]
Abstract
Aquaporins such as the plasma membrane intrinsic proteins (PIPs) allow water to move through cell membranes and are vital for stomatal movement in plants. Despite their importance, the dynamic changes in aquaporins during water efflux and influx have not been directly observed in real time in vivo. Here, to determine which factors regulate these changes during the bidirectional translocation of water, we examined aquaporin dynamics during the stomatal immune response to the bacterial flagellin-derived peptide flg22. The Arabidopsis (Arabidopsis thaliana) aquaporin mutant pip2;1 showed defects in the flg22-induced stomatal response. Variable-angle total internal reflection fluorescence microscopy revealed that the movement dynamics and dwell times of AQ6]GFP-AtPIP2;1 in guard cells and subsidiary cells exhibited cell type-specific dependencies on flg22. The cytoskeleton, rather than the cell wall, was the major factor regulating AtPIP2;1 dynamics, although both the cytoskeleton and cell wall might form bounded domains that restrict the diffusion of AtPIP2;1 in guard cells and subsidiary cells. Finally, our analysis revealed the different roles of cortical actin and microtubules in regulating AtPIP2;1 dynamics in guard cells, as well as subsidiary cells, under various conditions. Our observations shed light on the heterogeneous mechanisms that regulate membrane protein dynamics in plants in response to pathogens.
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Affiliation(s)
- Yaning Cui
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, College of Biological Sciences & Technology, Beijing Forestry University, Beijing 100083, China
| | - Yanxia Zhao
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, College of Biological Sciences & Technology, Beijing Forestry University, Beijing 100083, China
| | - Yuqing Lu
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, College of Biological Sciences & Technology, Beijing Forestry University, Beijing 100083, China
| | - Xiao Su
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, College of Biological Sciences & Technology, Beijing Forestry University, Beijing 100083, China
| | - Yingying Chen
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, College of Biological Sciences & Technology, Beijing Forestry University, Beijing 100083, China
| | - Yingbai Shen
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, College of Biological Sciences & Technology, Beijing Forestry University, Beijing 100083, China
| | - Jinxing Lin
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, College of Biological Sciences & Technology, Beijing Forestry University, Beijing 100083, China
- Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
| | - Xiaojuan Li
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, College of Biological Sciences & Technology, Beijing Forestry University, Beijing 100083, China
- Author for communication:
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Gil-Redondo JC, Iturri J, Ortega F, Pérez-Sen R, Weber A, Miras-Portugal MT, Toca-Herrera JL, Delicado EG. Nucleotides-Induced Changes in the Mechanical Properties of Living Endothelial Cells and Astrocytes, Analyzed by Atomic Force Microscopy. Int J Mol Sci 2021; 22:ijms22020624. [PMID: 33435130 PMCID: PMC7827192 DOI: 10.3390/ijms22020624] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 01/06/2021] [Accepted: 01/07/2021] [Indexed: 12/18/2022] Open
Abstract
Endothelial cells and astrocytes preferentially express metabotropic P2Y nucleotide receptors, which are involved in the maintenance of vascular and neural function. Among these, P2Y1 and P2Y2 receptors appear as main actors, since their stimulation induces intracellular calcium mobilization and activates signaling cascades linked to cytoskeletal reorganization. In the present work, we have analyzed, by means of atomic force microscopy (AFM) in force spectroscopy mode, the mechanical response of human umbilical vein endothelial cells (HUVEC) and astrocytes upon 2MeSADP and UTP stimulation. This approach allows for simultaneous measurement of variations in factors such as Young’s modulus, maximum adhesion force and rupture event formation, which reflect the potential changes in both the stiffness and adhesiveness of the plasma membrane. The largest effect was observed in both endothelial cells and astrocytes after P2Y2 receptor stimulation with UTP. Such exposure to UTP doubled the Young’s modulus and reduced both the adhesion force and the number of rupture events. In astrocytes, 2MeSADP stimulation also had a remarkable effect on AFM parameters. Additional studies performed with the selective P2Y1 and P2Y13 receptor antagonists revealed that the 2MeSADP-induced mechanical changes were mediated by the P2Y13 receptor, although they were negatively modulated by P2Y1 receptor stimulation. Hence, our results demonstrate that AFM can be a very useful tool to evaluate functional native nucleotide receptors in living cells.
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Affiliation(s)
- Juan Carlos Gil-Redondo
- Departamento de Bioquímica y Biología Molecular, Facultad de Veterinaria, Instituto Universitario de Investigación en Neuroquímica (IUIN), Instituto de Investigación Sanitaria del Hospital Clínico San Carlos (IdiSSC), Universidad Complutense Madrid, 28040 Madrid, Spain; (J.C.G.-R.); (R.P.-S.); (M.T.M.-P.)
- Department of Nanobiotechnology (DNBT), Institute for Biophysics, BOKU University for Natural Resources and Life Sciences, Muthgasse 11 (Simon Zeisel Haus), A-1190 Vienna, Austria; (A.W.); (J.L.T.-H.)
| | - Jagoba Iturri
- Department of Nanobiotechnology (DNBT), Institute for Biophysics, BOKU University for Natural Resources and Life Sciences, Muthgasse 11 (Simon Zeisel Haus), A-1190 Vienna, Austria; (A.W.); (J.L.T.-H.)
- Correspondence: (J.I.); (F.O.); (E.G.D.); Tel.: +43-1-47654-80354 (J.I.); +34-91-394-3892 (E.G.D.)
| | - Felipe Ortega
- Departamento de Bioquímica y Biología Molecular, Facultad de Veterinaria, Instituto Universitario de Investigación en Neuroquímica (IUIN), Instituto de Investigación Sanitaria del Hospital Clínico San Carlos (IdiSSC), Universidad Complutense Madrid, 28040 Madrid, Spain; (J.C.G.-R.); (R.P.-S.); (M.T.M.-P.)
- Correspondence: (J.I.); (F.O.); (E.G.D.); Tel.: +43-1-47654-80354 (J.I.); +34-91-394-3892 (E.G.D.)
| | - Raquel Pérez-Sen
- Departamento de Bioquímica y Biología Molecular, Facultad de Veterinaria, Instituto Universitario de Investigación en Neuroquímica (IUIN), Instituto de Investigación Sanitaria del Hospital Clínico San Carlos (IdiSSC), Universidad Complutense Madrid, 28040 Madrid, Spain; (J.C.G.-R.); (R.P.-S.); (M.T.M.-P.)
| | - Andreas Weber
- Department of Nanobiotechnology (DNBT), Institute for Biophysics, BOKU University for Natural Resources and Life Sciences, Muthgasse 11 (Simon Zeisel Haus), A-1190 Vienna, Austria; (A.W.); (J.L.T.-H.)
| | - María Teresa Miras-Portugal
- Departamento de Bioquímica y Biología Molecular, Facultad de Veterinaria, Instituto Universitario de Investigación en Neuroquímica (IUIN), Instituto de Investigación Sanitaria del Hospital Clínico San Carlos (IdiSSC), Universidad Complutense Madrid, 28040 Madrid, Spain; (J.C.G.-R.); (R.P.-S.); (M.T.M.-P.)
| | - José Luis Toca-Herrera
- Department of Nanobiotechnology (DNBT), Institute for Biophysics, BOKU University for Natural Resources and Life Sciences, Muthgasse 11 (Simon Zeisel Haus), A-1190 Vienna, Austria; (A.W.); (J.L.T.-H.)
| | - Esmerilda G. Delicado
- Departamento de Bioquímica y Biología Molecular, Facultad de Veterinaria, Instituto Universitario de Investigación en Neuroquímica (IUIN), Instituto de Investigación Sanitaria del Hospital Clínico San Carlos (IdiSSC), Universidad Complutense Madrid, 28040 Madrid, Spain; (J.C.G.-R.); (R.P.-S.); (M.T.M.-P.)
- Correspondence: (J.I.); (F.O.); (E.G.D.); Tel.: +43-1-47654-80354 (J.I.); +34-91-394-3892 (E.G.D.)
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8
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Cicconi A, Micheli E, Raffa GD, Cacchione S. Atomic Force Microscopy Reveals that the Drosophila Telomere-Capping Protein Verrocchio Is a Single-Stranded DNA-Binding Protein. Methods Mol Biol 2021; 2281:241-263. [PMID: 33847963 DOI: 10.1007/978-1-0716-1290-3_15] [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] [Indexed: 06/12/2023]
Abstract
Atomic force microscopy (AFM) is a scanning probe technique that allows visualization of biological samples with a nanometric resolution. Determination of the physical properties of biological molecules at a single-molecule level is achieved through topographic analysis of the sample adsorbed on a flat and smooth surface. AFM has been widely used for the structural analysis of nucleic acid-protein interactions, providing insights on binding specificity and stoichiometry of proteins forming complexes with DNA substrates. Analysis of single-stranded DNA-binding proteins by AFM requires specific single-stranded/double-stranded hybrid DNA molecules as substrates for protein binding. In this chapter we describe the protocol for AFM characterization of binding properties of Drosophila telomeric protein Ver using DNA constructs that mimic the structure of chromosome ends. We provide details on the methodology used, including the procedures for the generation of DNA substrates, the preparation of samples for AFM visualization, and the data analysis of AFM images. The presented procedure can be adapted for the structural studies of any single-stranded DNA-binding protein.
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Affiliation(s)
- Alessandro Cicconi
- Dipartimento di Biologia e Biotecnologie 'C. Darwin', Sapienza, Università di Roma, Rome, Italy.
- Department of Laboratory Medicine, Yale University School of Medicine, New Haven, CT, USA.
| | - Emanuela Micheli
- Dipartimento di Biologia e Biotecnologie 'C. Darwin', Sapienza, Università di Roma, Rome, Italy
| | - Grazia Daniela Raffa
- Dipartimento di Biologia e Biotecnologie 'C. Darwin', Sapienza, Università di Roma, Rome, Italy
| | - Stefano Cacchione
- Dipartimento di Biologia e Biotecnologie 'C. Darwin', Sapienza, Università di Roma, Rome, Italy.
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9
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Bergler F, Fuentes C, Kadir MF, Navarrete C, Supple J, Barrera NP, Edwardson JM. Activation of P2X4 receptors induces an increase in the area of the extracellular region and a decrease in receptor mobility. FEBS Lett 2020; 594:4381-4389. [PMID: 32979222 DOI: 10.1002/1873-3468.13942] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Accepted: 09/15/2020] [Indexed: 11/09/2022]
Abstract
The P2X4 receptor (P2X4R) is an ATP-gated cation channel. Here, we used fast-scan atomic force microscopy (AFM) to visualize changes in the structure and mobility of individual P2X4Rs in response to activation. P2X4Rs were purified from detergent extracts of transfected cells and integrated into lipid bilayers. Activation resulted in a rapid (2 s) and substantial (10-20 nm2 ) increase in the cross-sectional area of the extracellular region of the receptor and a corresponding decrease in receptor mobility. Both effects were blocked by the P2X4R antagonist 5-BDBD. Addition of cholesterol to the bilayer reduced receptor mobility, although the ATP-induced reduction in mobility was still observed. We suggest that the observed responses to activation may have functional consequences for purinergic signalling.
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Affiliation(s)
- Frederik Bergler
- Department of Pharmacology, University of Cambridge, Cambridge, UK
| | - Christian Fuentes
- Department of Pharmacology, University of Cambridge, Cambridge, UK.,Department of Physiology, Faculty of Biological Sciences, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Md Fahim Kadir
- Department of Pharmacology, University of Cambridge, Cambridge, UK
| | - Camilo Navarrete
- Department of Pharmacology, University of Cambridge, Cambridge, UK.,Department of Physiology, Faculty of Biological Sciences, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Jack Supple
- Department of Pharmacology, University of Cambridge, Cambridge, UK
| | - Nelson P Barrera
- Department of Physiology, Faculty of Biological Sciences, Pontificia Universidad Católica de Chile, Santiago, Chile
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10
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Resolving the Ionotropic P2X4 Receptor Mystery Points Towards a New Therapeutic Target for Cardiovascular Diseases. Int J Mol Sci 2020; 21:ijms21145005. [PMID: 32679900 PMCID: PMC7404342 DOI: 10.3390/ijms21145005] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 07/09/2020] [Accepted: 07/13/2020] [Indexed: 12/18/2022] Open
Abstract
Adenosine triphosphate (ATP) is a primordial versatile autacoid that changes its role from an intracellular energy saver to a signaling molecule once released to the extracellular milieu. Extracellular ATP and its adenosine metabolite are the main activators of the P2 and P1 purinoceptor families, respectively. Mounting evidence suggests that the ionotropic P2X4 receptor (P2X4R) plays pivotal roles in the regulation of the cardiovascular system, yet further therapeutic advances have been hampered by the lack of selective P2X4R agonists. In this review, we provide the state of the art of the P2X4R activity in the cardiovascular system. We also discuss the role of P2X4R activation in kidney and lungs vis a vis their interplay to control cardiovascular functions and dysfunctions, including putative adverse effects emerging from P2X4R activation. Gathering this information may prompt further development of selective P2X4R agonists and its translation to the clinical practice.
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11
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Tsuda M. Microglia-Mediated Regulation of Neuropathic Pain: Molecular and Cellular Mechanisms. Biol Pharm Bull 2020; 42:1959-1968. [PMID: 31787711 DOI: 10.1248/bpb.b19-00715] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Pain is a defense system that responds rapidly to harmful internal and external stimuli through the somatosensory neuronal pathway. However, damage to the nervous system through cancer, diabetes, infection, autoimmune disease, chemotherapy or trauma often leads to neuropathic pain, a debilitating chronic pain condition. Neuropathic pain is not simply a temporal continuum of acute nociceptive signals from the periphery, but rather due to pathologically altered functions in the nervous system, which shift the net neuronal excitatory balance toward excitation. Although alterations were long thought to be a result of changes in neurons, but an increasing body of evidence over the past decades indicates the necessity and sufficiency of microglia, the tissue-resident macrophages of the spinal cord and brain, for nerve injury-induced malfunction of the nervous system. In this review article, I describe our current understanding of the molecular and cellular mechanisms underlying the role of microglia in the pathogenesis of neuropathic pain and discuss the therapeutic potential of microglia from recent advances in the development of new drugs targeting microglia.
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Affiliation(s)
- Makoto Tsuda
- Department of Life Innovation, Graduate School of Pharmaceutical Sciences, Kyushu University
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12
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Ruiz-Rodríguez VM, Cortes-García JD, de Jesús Briones-Espinoza M, Rodríguez-Varela E, Vega-Cárdenas M, Gómez-Otero A, García-Hernández MH, Portales-Pérez DP. P2X4 receptor as a modulator in the function of P2X receptor in CD4+ T cells from peripheral blood and adipose tissue. Mol Immunol 2019; 112:369-377. [PMID: 31279218 DOI: 10.1016/j.molimm.2019.06.009] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Revised: 03/25/2019] [Accepted: 06/16/2019] [Indexed: 10/26/2022]
Abstract
Obesity is characterized by immune cell infiltration and inflammation. Purinergic receptors such as P2X1, 4 and 7 are expressed on immune cells and their activation contributes with an inflammatory response. However, the simultaneous expression of P2X1, 4 and 7 during overweight or obesity have not been described. Therefore, the aim of this study was to determine single and simultaneously expression and function of the P2X1, 4 and 7 receptors in lymphocytes and CD4 + T cells from peripheral blood (PB) and adipose tissue (AT). Our results showed a higher expression of the P2X4 receptor on CD4 + T cells from PB regarding P2X7 and P2X1 receptor expression. In addition, P2X4 receptor expression on CD4 + T cells from PB and AT was increased in individuals with BMI ≥ 25 Kg/m2. Moreover, a higher simultaneous expression of the P2X4 and P2X7 receptors on CD4 + T cells from AT compared to CD4 + T cells expressing P2X1 and P2X7 receptors simultaneously. Besides, CD4 + T cells expressing P2X4 and P2X7 receptors from PB and AT were augmented in individuals with BMI ≥ 25 Kg/m2. In addition, the percentage of lymphocytes and also CD4 + T cells expressing P2X4 receptor were elevated both in PB and AT compared to cells expressing P2X7 or P2X1. However, CD4 + T cells expressing P2X4 and P2X7 were augmented in AT compared to PB. The function of the receptors showed a lower shedding of CD62 L in adipose tissue mononuclear cells (ATMC) compared with peripheral blood mononuclear cells (PBMC) and a greater participation of P2X4 in the mobilization of intracellular calcium. We concluded that it was possible to determine for the first time the simultaneous expression of purinergic receptors in ATMC, where the P2X4 receptor has a greater participation in the activation of CD4 + T cells possibly modulating the function of the other two receptors.
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Affiliation(s)
- Victor Manuel Ruiz-Rodríguez
- Laboratory of Immunology and Cellular and Molecular Biology, Faculty of Chemical Sciences, UASLP, San Luis Potosí, S.L.P., Mexico
| | - Juan Diego Cortes-García
- Laboratory of Immunology and Cellular and Molecular Biology, Faculty of Chemical Sciences, UASLP, San Luis Potosí, S.L.P., Mexico
| | | | - Eduardo Rodríguez-Varela
- Laboratory of Immunology and Cellular and Molecular Biology, Faculty of Chemical Sciences, UASLP, San Luis Potosí, S.L.P., Mexico
| | - Mariela Vega-Cárdenas
- Laboratory of Immunology and Cellular and Molecular Biology, Faculty of Chemical Sciences, UASLP, San Luis Potosí, S.L.P., Mexico
| | - Arturo Gómez-Otero
- Aesthetic and Corrective Plastic Surgery Clinic, San Luis Potosí, S.L.P., Mexico
| | | | - Diana Patricia Portales-Pérez
- Laboratory of Immunology and Cellular and Molecular Biology, Faculty of Chemical Sciences, UASLP, San Luis Potosí, S.L.P., Mexico; Translational and Molecular Medicine Department, Research Center for Health Sciences and Biomedicine, Autonomous University of San Luis Potosí, Mexico.
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13
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Heath GR, Scheuring S. Advances in high-speed atomic force microscopy (HS-AFM) reveal dynamics of transmembrane channels and transporters. Curr Opin Struct Biol 2019; 57:93-102. [PMID: 30878714 DOI: 10.1016/j.sbi.2019.02.008] [Citation(s) in RCA: 57] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2019] [Revised: 02/12/2019] [Accepted: 02/13/2019] [Indexed: 02/07/2023]
Abstract
Recent advances in high-speed atomic force microscopy (HS-AFM) have made it possible to study the conformational dynamics of single unlabeled transmembrane channels and transporters. Improving environmental control with the integration of a non-disturbing buffer exchange system, which in turn allows the gradual change of conditions during HS-AFM operation, has provided a breakthrough toward the performance of structural titration experiments. Further advancements in temporal resolution with the use of line scanning and height spectroscopy techniques show how high-speed atomic force microscopy can measure millisecond to microsecond dynamics, pushing this method beyond current spatial and temporal limits offered by less direct techniques.
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Affiliation(s)
- George R Heath
- Weill Cornell Medicine, Department of Anesthesiology, 1300 York Avenue, New York, NY 10065, USA; Weill Cornell Medicine, Department of Physiology and Biophysics, 1300 York Avenue, New York, NY 10065, USA
| | - Simon Scheuring
- Weill Cornell Medicine, Department of Anesthesiology, 1300 York Avenue, New York, NY 10065, USA; Weill Cornell Medicine, Department of Physiology and Biophysics, 1300 York Avenue, New York, NY 10065, USA.
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14
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OSHIMA A, SUMITOMO K. Vesicle Fusion with Artificial Bilayer Lipid Membrane Induced by Electrostatic Interaction. BUNSEKI KAGAKU 2019. [DOI: 10.2116/bunsekikagaku.68.23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
- Azusa OSHIMA
- NTT Basic Research Laboratories, NTT Corporation
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15
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刘 林, 魏 余, 刘 文, 孙 彤, 王 凯, 汪 颖, 李 宾. [Progress in the applications of high-speed atomic force microscopy in cell biology]. NAN FANG YI KE DA XUE XUE BAO = JOURNAL OF SOUTHERN MEDICAL UNIVERSITY 2018; 38:931-937. [PMID: 30187879 PMCID: PMC6744042 DOI: 10.3969/j.issn.1673-4254.2018.08.05] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 03/10/2018] [Indexed: 12/24/2022]
Abstract
Without losing its high resolution, high-speed atomic force microscope (HS-AFM) represents a perfect combinationof scanning speed and precision and allows real-time and in situ observation of the dynamic processes in a biological system atboth the cellular and molecular levels. By combining the extremely high temporal resolution with the spatial resolution andcoupling with other advanced technologies, HS-AFM shows promising prospects for applications in life sciences such as cellbiology. In this review, we summarize the latest progress of HS-AFM in the field of cell biology, and discuss the impact ofenvironmental factors on conformation dynamics of DNA, the binding processes between DNA and protein, the domainchanges of membrane proteins, motility of myosin, and surface structure changes of living cells.
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Affiliation(s)
- 林 刘
- 中国科学院上海应用物理研究所物理生物研究室,上海 201800Laboratory of Physical Biology, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China
- 中国科学院大学,北京 100049University of Chinese Academy of Sciences, Beijing 100049, China
| | - 余辉 魏
- 中国科学院上海应用物理研究所物理生物研究室,上海 201800Laboratory of Physical Biology, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China
| | - 文静 刘
- 中国科学院上海应用物理研究所物理生物研究室,上海 201800Laboratory of Physical Biology, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China
- 中国科学院大学,北京 100049University of Chinese Academy of Sciences, Beijing 100049, China
| | - 彤 孙
- 中国科学院上海应用物理研究所物理生物研究室,上海 201800Laboratory of Physical Biology, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China
- 中国科学院大学,北京 100049University of Chinese Academy of Sciences, Beijing 100049, China
| | - 凯喆 王
- 中国科学院上海应用物理研究所物理生物研究室,上海 201800Laboratory of Physical Biology, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China
- 中国科学院大学,北京 100049University of Chinese Academy of Sciences, Beijing 100049, China
| | - 颖 汪
- 中国科学院上海应用物理研究所物理生物研究室,上海 201800Laboratory of Physical Biology, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China
| | - 宾 李
- 中国科学院上海应用物理研究所物理生物研究室,上海 201800Laboratory of Physical Biology, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China
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16
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Uchihashi T, Scheuring S. Applications of high-speed atomic force microscopy to real-time visualization of dynamic biomolecular processes. Biochim Biophys Acta Gen Subj 2018; 1862:229-240. [DOI: 10.1016/j.bbagen.2017.07.010] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2017] [Accepted: 07/13/2017] [Indexed: 12/12/2022]
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17
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Mohan Bangalore D, Tessmer I. Unique insight into protein-DNA interactions from single molecule atomic force microscopy. AIMS BIOPHYSICS 2018. [DOI: 10.3934/biophy.2018.3.194] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
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18
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Suurväli J, Boudinot P, Kanellopoulos J, Rüütel Boudinot S. P2X4: A fast and sensitive purinergic receptor. Biomed J 2017; 40:245-256. [PMID: 29179879 PMCID: PMC6138603 DOI: 10.1016/j.bj.2017.06.010] [Citation(s) in RCA: 108] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2017] [Revised: 06/28/2017] [Accepted: 06/30/2017] [Indexed: 01/31/2023] Open
Abstract
Extracellular nucleotides have been recognized as important mediators of activation, triggering multiple responses via plasma membrane receptors known as P2 receptors. P2 receptors comprise P2X ionotropic receptors and G protein-coupled P2Y receptors. P2X receptors are expressed in many tissues, where they are involved in a number of functions including synaptic transmission, muscle contraction, platelet aggregation, inflammation, macrophage activation, differentiation and proliferation, neuropathic and inflammatory pain. P2X4 is one of the most sensitive purinergic receptors (at nanomolar ATP concentrations), about one thousand times more than the archetypal P2X7. P2X4 is widely expressed in central and peripheral neurons, in microglia, and also found in various epithelial tissues and endothelial cells. It localizes on the plasma membrane, but also in intracellular compartments. P2X4 is preferentially localized in lysosomes, where it is protected from proteolysis by its glycosylation. High ATP concentration in the lysosomes does not activate P2X4 at low pH; P2X4 gets activated by intra-lysosomal ATP only in its fully dissociated tetra-anionic form, when the pH increases to 7.4. Thus, P2X4 is functioning as a Ca2+-channel after the fusion of late endosomes and lysosomes. P2X4 modulates major neurotransmitter systems and regulates alcohol-induced responses in microglia. P2X4 is one of the key receptors mediating neuropathic pain. However, injury-induced upregulation of P2X4 expression is gender dependent and plays a key role in pain difference between males and females. P2X4 is also involved in inflammation. Extracellular ATP being a pro-inflammatory molecule, P2X4 can trigger inflammation in response to high ATP release. It is therefore involved in multiple pathologies, like post-ischemic inflammation, rheumatoid arthritis, airways inflammation in asthma, neurodegenerative diseases and even metabolic syndrome. Although P2X4 remains poorly characterized, more studies are needed as it is likely to be a potential therapeutic target in these multiple pathologies.
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Affiliation(s)
- Jaanus Suurväli
- Department of Chemistry and Biotechnology, Tallinn University of Technology, Tallinn, Estonia
| | - Pierre Boudinot
- Virologie et Immunologie Moléculaires, INRA, Université Paris-Saclay, Jouy-en-Josas, France
| | - Jean Kanellopoulos
- Institute for Integrative Biology of the Cell (I2BC) CEA, CNRS, Univ. Paris-Sud, Université Paris-Saclay, Gif-sur-Yvette cedex, France
| | - Sirje Rüütel Boudinot
- Department of Chemistry and Biotechnology, Tallinn University of Technology, Tallinn, Estonia.
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19
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Yu M, Liu H, Dong Z, Xiao J, Su B, Fan L, Komis G, Šamaj J, Lin J, Li R. The dynamics and endocytosis of Flot1 protein in response to flg22 in Arabidopsis. JOURNAL OF PLANT PHYSIOLOGY 2017; 215:73-84. [PMID: 28582732 DOI: 10.1016/j.jplph.2017.05.010] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2017] [Revised: 05/16/2017] [Accepted: 05/16/2017] [Indexed: 05/14/2023]
Abstract
Membrane microdomains play vital roles in the process of bacterial infection. The membrane microdomain-associated protein Flot1 acts in an endocytic pathway and is required for seedling development, however, whether Flot1 is a part of host defense mechanisms remains unknown. During an analysis of callose deposition, we found that Flot1 amiRNAi mutants exhibited defects in response to flg22. Using variable-angle total internal reflection fluorescence microscopy (VA-TIRFM), structured illumination microscopy (SIM) and fluorescence cross spectroscopy (FCS), we determined that the dynamic behavior of GFP-Flot1 in Arabidopsis thaliana cotyledon epidermal cells changed significantly in plants treated with the elicitor flg22. Moreover, we found that Flot1 was constitutively recycled via an endocytic pathway and that flg22 could promote endocytosis. Importantly, targeting of Flot1 to the late endosome/vacuole for degradation increased in response to flg22 treatment; immunoblot analysis showed that when triggered by flg22, GFP-Flot1 was gradually degraded in a time-dependent manner. Taken together, these findings support the hypothesis that the changing of dynamics and oligomeric states can promote the endocytosis and degradation of Flot1 under flg22 treatment in plant cells.
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Affiliation(s)
- Meng Yu
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, Beijing Forestry University, Beijing 100083, China; College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, China
| | - Haijiao Liu
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, Beijing Forestry University, Beijing 100083, China; College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, China
| | - Ziyi Dong
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, Beijing Forestry University, Beijing 100083, China; College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, China
| | - Jianwei Xiao
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, Beijing Forestry University, Beijing 100083, China; College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, China
| | - Bodan Su
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, Beijing Forestry University, Beijing 100083, China; College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, China
| | - Lusheng Fan
- Department of Botany and Plant Sciences, University of California, Riverside, CA 92521, USA
| | - George Komis
- Centre of the Region Hana for Biotechnological and Agricultural Research, Faculty of Science, Palacky University, 78301, Olomouc, Czech Republic
| | - Jozef Šamaj
- Centre of the Region Hana for Biotechnological and Agricultural Research, Faculty of Science, Palacky University, 78301, Olomouc, Czech Republic
| | - Jinxing Lin
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, Beijing Forestry University, Beijing 100083, China; College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, China
| | - Ruili Li
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, Beijing Forestry University, Beijing 100083, China; College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, China.
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20
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Stokes L, Layhadi JA, Bibic L, Dhuna K, Fountain SJ. P2X4 Receptor Function in the Nervous System and Current Breakthroughs in Pharmacology. Front Pharmacol 2017; 8:291. [PMID: 28588493 PMCID: PMC5441391 DOI: 10.3389/fphar.2017.00291] [Citation(s) in RCA: 100] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2017] [Accepted: 05/05/2017] [Indexed: 12/18/2022] Open
Abstract
Adenosine 5′-triphosphate is a well-known extracellular signaling molecule and neurotransmitter known to activate purinergic P2X receptors. Information has been elucidated about the structure and gating of P2X channels following the determination of the crystal structure of P2X4 (zebrafish), however, there is still much to discover regarding the role of this receptor in the central nervous system (CNS). In this review we provide an overview of what is known about P2X4 expression in the CNS and discuss evidence for pathophysiological roles in neuroinflammation and neuropathic pain. Recent advances in the development of pharmacological tools including selective antagonists (5-BDBD, PSB-12062, BX430) and positive modulators (ivermectin, avermectins, divalent cations) of P2X4 will be discussed.
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Affiliation(s)
- Leanne Stokes
- School of Pharmacy, University of East Anglia, Norwich Research ParkNorwich, United Kingdom.,School of Biomedical and Health Sciences, RMIT University, BundooraVIC, Australia
| | - Janice A Layhadi
- Biomedical Research Centre, School of Biological Sciences, University of East AngliaNorwich, United Kingdom
| | - Lucka Bibic
- School of Pharmacy, University of East Anglia, Norwich Research ParkNorwich, United Kingdom
| | - Kshitija Dhuna
- School of Biomedical and Health Sciences, RMIT University, BundooraVIC, Australia
| | - Samuel J Fountain
- Biomedical Research Centre, School of Biological Sciences, University of East AngliaNorwich, United Kingdom
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21
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On the permeation of large organic cations through the pore of ATP-gated P2X receptors. Proc Natl Acad Sci U S A 2017; 114:E3786-E3795. [PMID: 28442564 DOI: 10.1073/pnas.1701379114] [Citation(s) in RCA: 72] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Pore dilation is thought to be a hallmark of purinergic P2X receptors. The most commonly held view of this unusual process posits that under prolonged ATP exposure the ion pore expands in a striking manner from an initial small-cation conductive state to a dilated state, which allows the passage of larger synthetic cations, such as N-methyl-d-glucamine (NMDG+). However, this mechanism is controversial, and the identity of the natural large permeating cations remains elusive. Here, we provide evidence that, contrary to the time-dependent pore dilation model, ATP binding opens an NMDG+-permeable channel within milliseconds, with a conductance that remains stable over time. We show that the time course of NMDG+ permeability superimposes that of Na+ and demonstrate that the molecular motions leading to the permeation of NMDG+ are very similar to those that drive Na+ flow. We found, however, that NMDG+ "percolates" 10 times slower than Na+ in the open state, likely due to a conformational and orientational selection of permeating molecules. We further uncover that several P2X receptors, including those able to desensitize, are permeable not only to NMDG+ but also to spermidine, a large natural cation involved in ion channel modulation, revealing a previously unrecognized P2X-mediated signaling. Altogether, our data do not support a time-dependent dilation of the pore on its own but rather reveal that the open pore of P2X receptors is wide enough to allow the permeation of large organic cations, including natural ones. This permeation mechanism has considerable physiological significance.
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22
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Modulation of Pain and Itch by Spinal Glia. Neurosci Bull 2017; 34:178-185. [PMID: 28389872 DOI: 10.1007/s12264-017-0129-y] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Accepted: 03/01/2017] [Indexed: 12/30/2022] Open
Abstract
Chronic pain and itch are a pathological operation of the somatosensory system at the levels of primary sensory neurons, spinal cord and brain. Pain and itch are clearly distinct sensations, and recent studies have revealed the separate neuronal pathways that are involved in each sensation. However, the mechanisms by which these sensations turn into a pathological chronic state are poorly understood. A proposed mechanism underlying chronic pain and itch involves abnormal excitability in dorsal horn neurons in the spinal cord. Furthermore, an increasing body of evidence from models of chronic pain and itch has indicated that synaptic hyperexcitability in the spinal dorsal horn might not be a consequence simply of changes in neurons, but rather of multiple alterations in glial cells. Thus, understanding the key roles of glial cells may provide us with exciting insights into the mechanisms of chronicity of pain and itch, and lead to new targets for treating chronic pain and itch.
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23
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Tsuda M, Koga K, Chen T, Zhuo M. Neuronal and microglial mechanisms for neuropathic pain in the spinal dorsal horn and anterior cingulate cortex. J Neurochem 2017; 141:486-498. [DOI: 10.1111/jnc.14001] [Citation(s) in RCA: 86] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Revised: 02/02/2017] [Accepted: 02/08/2017] [Indexed: 01/02/2023]
Affiliation(s)
- Makoto Tsuda
- Department of Life Innovation; Graduate School of Pharmaceutical Sciences; Kyushu University; Fukuoka Japan
| | - Kohei Koga
- Department of Neurophysiology; Hirosaki University Graduate School of Medicine; Hirosaki Japan
- Department of Physiology; University of Toronto; Toronto Canada
| | - Tao Chen
- Department of Physiology; University of Toronto; Toronto Canada
- Department of Anatomy, Histology and Embryology; Fourth Military Medical University; Xi'an Shaanxi China
- Center for Neuron and Disease; Frontier Institutes of Science and Technology; Xi'an Jiaotong University; Xi'an Shanxi China
| | - Min Zhuo
- Department of Physiology; University of Toronto; Toronto Canada
- Center for Neuron and Disease; Frontier Institutes of Science and Technology; Xi'an Jiaotong University; Xi'an Shanxi China
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24
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Wang J, Sun LF, Cui WW, Zhao WS, Ma XF, Li B, Liu Y, Yang Y, Hu YM, Huang LD, Cheng XY, Li L, Lu XY, Tian Y, Yu Y. Intersubunit physical couplings fostered by the left flipper domain facilitate channel opening of P2X4 receptors. J Biol Chem 2017; 292:7619-7635. [PMID: 28302727 DOI: 10.1074/jbc.m116.771121] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2016] [Revised: 03/03/2017] [Indexed: 12/14/2022] Open
Abstract
P2X receptors are ATP-gated trimeric channels with important roles in diverse pathophysiological functions. A detailed understanding of the mechanism underlying the gating process of these receptors is thus fundamentally important and may open new therapeutic avenues. The left flipper (LF) domain of the P2X receptors is a flexible loop structure, and its coordinated motions together with the dorsal fin (DF) domain are crucial for the channel gating of the P2X receptors. However, the mechanism underlying the crucial role of the LF domain in the channel gating remains obscure. Here, we propose that the ATP-induced allosteric changes of the LF domain enable it to foster intersubunit physical couplings among the DF and two lower body domains, which are pivotal for the channel gating of P2X4 receptors. Metadynamics analysis indicated that these newly established intersubunit couplings correlate well with the ATP-bound open state of the receptors. Moreover, weakening or strengthening these physical interactions with engineered intersubunit metal bridges remarkably decreased or increased the open probability of the receptors, respectively. Further disulfide cross-linking and covalent modification confirmed that the intersubunit physical couplings among the DF and two lower body domains fostered by the LF domain at the open state act as an integrated structural element that is stringently required for the channel gating of P2X4 receptors. Our observations provide new mechanistic insights into P2X receptor activation and will stimulate development of new allosteric modulators of P2X receptors.
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Affiliation(s)
- Jin Wang
- From the Department of Pharmacology and Chemical Biology, Institute of Medical Sciences and Hongqiao International Institute of Medicine of Shanghai Tongren Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Liang-Fei Sun
- From the Department of Pharmacology and Chemical Biology, Institute of Medical Sciences and Hongqiao International Institute of Medicine of Shanghai Tongren Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Wen-Wen Cui
- From the Department of Pharmacology and Chemical Biology, Institute of Medical Sciences and Hongqiao International Institute of Medicine of Shanghai Tongren Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Wen-Shan Zhao
- From the Department of Pharmacology and Chemical Biology, Institute of Medical Sciences and Hongqiao International Institute of Medicine of Shanghai Tongren Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Xue-Fei Ma
- From the Department of Pharmacology and Chemical Biology, Institute of Medical Sciences and Hongqiao International Institute of Medicine of Shanghai Tongren Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China.,the College of Bioscience and Biotechnology, Hunan Agricultural University, Changsha 410128, China, and
| | - Bin Li
- From the Department of Pharmacology and Chemical Biology, Institute of Medical Sciences and Hongqiao International Institute of Medicine of Shanghai Tongren Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China.,the College of Bioscience and Biotechnology, Hunan Agricultural University, Changsha 410128, China, and
| | - Yan Liu
- From the Department of Pharmacology and Chemical Biology, Institute of Medical Sciences and Hongqiao International Institute of Medicine of Shanghai Tongren Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Yang Yang
- From the Department of Pharmacology and Chemical Biology, Institute of Medical Sciences and Hongqiao International Institute of Medicine of Shanghai Tongren Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - You-Min Hu
- From the Department of Pharmacology and Chemical Biology, Institute of Medical Sciences and Hongqiao International Institute of Medicine of Shanghai Tongren Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Li-Dong Huang
- From the Department of Pharmacology and Chemical Biology, Institute of Medical Sciences and Hongqiao International Institute of Medicine of Shanghai Tongren Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Xiao-Yang Cheng
- From the Department of Pharmacology and Chemical Biology, Institute of Medical Sciences and Hongqiao International Institute of Medicine of Shanghai Tongren Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Lingyong Li
- the Department of Anesthesiology and Perioperative Medicine, University of Texas M.D. Anderson Cancer Center, Houston, Texas 77030
| | - Xiang-Yang Lu
- the College of Bioscience and Biotechnology, Hunan Agricultural University, Changsha 410128, China, and
| | - Yun Tian
- the College of Bioscience and Biotechnology, Hunan Agricultural University, Changsha 410128, China, and
| | - Ye Yu
- From the Department of Pharmacology and Chemical Biology, Institute of Medical Sciences and Hongqiao International Institute of Medicine of Shanghai Tongren Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China, .,the College of Bioscience and Biotechnology, Hunan Agricultural University, Changsha 410128, China, and
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25
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Tsuda M. P2 receptors, microglial cytokines and chemokines, and neuropathic pain. J Neurosci Res 2016; 95:1319-1329. [DOI: 10.1002/jnr.23816] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Revised: 05/19/2016] [Accepted: 06/13/2016] [Indexed: 01/12/2023]
Affiliation(s)
- Makoto Tsuda
- Department of Life Innovation, Department of Molecular and System Pharmacology, Graduate School of Pharmaceutical Sciences; Kyushu University; Fukuoka Japan
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26
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Shan Y, Wang H. The structure and function of cell membranes examined by atomic force microscopy and single-molecule force spectroscopy. Chem Soc Rev 2016; 44:3617-38. [PMID: 25893228 DOI: 10.1039/c4cs00508b] [Citation(s) in RCA: 102] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The cell membrane is one of the most complicated biological complexes, and long-term fierce debates regarding the cell membrane persist because of technical hurdles. With the rapid development of nanotechnology and single-molecule techniques, our understanding of cell membranes has substantially increased. Atomic force microscopy (AFM) has provided several unprecedented advances (e.g., high resolution, three-dimensional and in situ measurements) in the study of cell membranes and has been used to systematically dissect the membrane structure in situ from both sides of membranes; as a result, novel models of cell membranes have recently been proposed. This review summarizes the new progress regarding membrane structure using in situ AFM and single-molecule force spectroscopy (SMFS), which may shed light on the study of the structure and functions of cell membranes.
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Affiliation(s)
- Yuping Shan
- State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin 130022, P. R. China.
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27
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Insights into the channel gating of P2X receptors from structures, dynamics and small molecules. Acta Pharmacol Sin 2016; 37:44-55. [PMID: 26725734 DOI: 10.1038/aps.2015.127] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Accepted: 11/02/2015] [Indexed: 12/16/2022] Open
Abstract
P2X receptors, as ATP-gated non-selective trimeric ion channels, are permeable to Na(+), K(+) and Ca(2+). Comparing with other ligand-gated ion channel families, P2X receptors are distinct in their unique gating properties and pathophysiological roles, and have attracted attention as promising drug targets for a variety of diseases, such as neuropathic pain, multiple sclerosis, rheumatoid arthritis and thrombus. Several small molecule inhibitors for distinct P2X subtypes have entered into clinical trials. However, many questions regarding the gating mechanism of P2X remain unsolved. The structural determinations of P2X receptors at the resting and ATP-bound open states revealed that P2X receptor gating is a cooperative allosteric process involving multiple domains, which marks the beginning of the post-structure era of P2X research at atomic level. Here, we review the current knowledge on the structure-function relationship of P2X receptors, depict the whole picture of allosteric changes during the channel gating, and summarize the active sites that may contribute to new strategies for developing novel allosteric drugs targeting P2X receptors.
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28
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Habermacher C, Dunning K, Chataigneau T, Grutter T. Molecular structure and function of P2X receptors. Neuropharmacology 2015; 104:18-30. [PMID: 26231831 DOI: 10.1016/j.neuropharm.2015.07.032] [Citation(s) in RCA: 79] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Revised: 07/23/2015] [Accepted: 07/26/2015] [Indexed: 12/22/2022]
Abstract
ATP-gated P2X receptors are trimeric ion channels selective to cations. Recent progress in the molecular biophysics of these channels enables a better understanding of their function. In particular, data obtained from biochemical, electrophysiogical and molecular engineering in the light of recent X-ray structures now allow delineation of the principles of ligand binding, channel opening and allosteric modulation. However, although a picture emerges as to how ATP triggers channel opening, there are a number of intriguing questions that remain to be answered, in particular how the pore itself opens in response to ATP and how the intracellular domain, for which structural information is limited, moves during activation. In this review, we provide a summary of functional studies in the context of the post-structure era, aiming to clarify our understanding of the way in which P2X receptors function in response to ATP binding, as well as the mechanism by which allosteric modulators are able to regulate receptor function. This article is part of the Special Issue entitled 'Purines in Neurodegeneration and Neuroregeneration'.
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Affiliation(s)
- Chloé Habermacher
- Centre National de la Recherche Scientifique, Unité Mixte de Recherche 7199, Laboratoire de Conception et Application de Molécules Bioactives, Équipe de Chimie et Neurobiologie Moléculaire, F-67400, Illkirch, France; Université de Strasbourg, Faculté de Pharmacie, F-67400, Illkirch, France
| | - Kate Dunning
- Centre National de la Recherche Scientifique, Unité Mixte de Recherche 7199, Laboratoire de Conception et Application de Molécules Bioactives, Équipe de Chimie et Neurobiologie Moléculaire, F-67400, Illkirch, France; Université de Strasbourg, Faculté de Pharmacie, F-67400, Illkirch, France
| | - Thierry Chataigneau
- Centre National de la Recherche Scientifique, Unité Mixte de Recherche 7199, Laboratoire de Conception et Application de Molécules Bioactives, Équipe de Chimie et Neurobiologie Moléculaire, F-67400, Illkirch, France; Université de Strasbourg, Faculté de Pharmacie, F-67400, Illkirch, France
| | - Thomas Grutter
- Centre National de la Recherche Scientifique, Unité Mixte de Recherche 7199, Laboratoire de Conception et Application de Molécules Bioactives, Équipe de Chimie et Neurobiologie Moléculaire, F-67400, Illkirch, France; Université de Strasbourg, Faculté de Pharmacie, F-67400, Illkirch, France.
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29
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Tanaka A, Tanaka R, Kasai N, Tsukada S, Okajima T, Sumitomo K. Time-lapse imaging of morphological changes in a single neuron during the early stages of apoptosis using scanning ion conductance microscopy. J Struct Biol 2015; 191:32-8. [DOI: 10.1016/j.jsb.2015.06.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2015] [Revised: 06/01/2015] [Accepted: 06/02/2015] [Indexed: 12/30/2022]
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30
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Oiki S. Channel function reconstitution and re-animation: a single-channel strategy in the postcrystal age. J Physiol 2015; 593:2553-73. [PMID: 25833254 DOI: 10.1113/jp270025] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2014] [Accepted: 03/24/2015] [Indexed: 01/30/2023] Open
Abstract
The most essential properties of ion channels for their physiologically relevant functions are ion-selective permeation and gating. Among the channel species, the potassium channel is primordial and the most ubiquitous in the biological world, and knowledge of this channel underlies the understanding of features of other ion channels. The strategy applied to studying channels changed dramatically after the crystal structure of the potassium channel was resolved. Given the abundant structural information available, we exploited the bacterial KcsA potassium channel as a simple model channel. In the postcrystal age, there are two effective frameworks with which to decipher the functional codes present in the channel structure, namely reconstitution and re-animation. Complex channel proteins are decomposed into essential functional components, and well-examined parts are rebuilt for integrating channel function in the membrane (reconstitution). Permeation and gating are dynamic operations, and one imagines the active channel by breathing life into the 'frozen' crystal (re-animation). Capturing the motion of channels at the single-molecule level is necessary to characterize the behaviour of functioning channels. Advanced techniques, including diffracted X-ray tracking, lipid bilayer methods and high-speed atomic force microscopy, have been used. Here, I present dynamic pictures of the KcsA potassium channel from the submolecular conformational changes to the supramolecular collective behaviour of channels in the membrane. These results form an integrated picture of the active channel and offer insights into the processes underlying the physiological function of the channel in the cell membrane.
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Affiliation(s)
- Shigetoshi Oiki
- Department of Molecular Physiology and Biophysics, Faculty of Medical Sciences, University of Fukui, Fukui, 910-1193, Japan
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31
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SUMINO A, YAMAMOTO D, SUMIKAMA T, IWAMOTO M, DEWA T, OIKI S. Structure and Dynamics of Membrane-embedded KcsA Potassium Channel Revealed by Atomic Force Microscopy. ACTA ACUST UNITED AC 2015. [DOI: 10.2142/biophys.55.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Affiliation(s)
- Ayumi SUMINO
- PRESTO, Japan Science and Technology Agency (JST)
- Department of Molecular Physiology and Biophysics, Faculty of Medical Sciences, University of Fukui
| | | | - Takashi SUMIKAMA
- Department of Molecular Physiology and Biophysics, Faculty of Medical Sciences, University of Fukui
| | - Masayuki IWAMOTO
- Department of Molecular Physiology and Biophysics, Faculty of Medical Sciences, University of Fukui
| | - Takehisa DEWA
- Department of Frontier Materials, Graduate School of Engineering, Nagoya Institute of Technology
| | - Shigetoshi OIKI
- Department of Molecular Physiology and Biophysics, Faculty of Medical Sciences, University of Fukui
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32
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Shibata T, Suzuki Y, Sugiyama H, Endo M, Saito H. Folding RNA-Protein Complex into Designed Nanostructures. Methods Mol Biol 2015; 1316:169-79. [PMID: 25967061 DOI: 10.1007/978-1-4939-2730-2_14] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
RNA-protein (RNP) complexes are promising biomaterials for the fields of nanotechnology and synthetic biology. Protein-responsive RNA sequences (RNP motifs) can be integrated into various RNAs, such as messenger RNA, short-hairpin RNA, and synthetic RNA nano-objects for a variety of purposes. Direct observation of RNP interaction in solution at high resolution is important in the design and construction of RNP-mediated nanostructures. Here we describe a method to construct and visualize RNP nanostructures that precisely arrange a target protein on the RNA scaffold with nanometer scale. High-speed AFM (HS-AFM) images of RNP nanostructures show that the folding of RNP complexes of defined sizes can be directly visualized at single RNP resolution in solution.
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Affiliation(s)
- Tomonori Shibata
- Center for iPS Cell Research and Application (CiRA), Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto, 606-8507, Japan
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33
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Henderson RM. Structural dynamics of single molecules studied with high-speed atomic force microscopy. Expert Opin Drug Discov 2014; 10:221-9. [DOI: 10.1517/17460441.2015.998195] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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34
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Ando T. High-speed AFM imaging. Curr Opin Struct Biol 2014; 28:63-8. [DOI: 10.1016/j.sbi.2014.07.011] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2014] [Revised: 07/22/2014] [Accepted: 07/22/2014] [Indexed: 11/26/2022]
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35
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Osada E, Suzuki Y, Hidaka K, Ohno H, Sugiyama H, Endo M, Saito H. Engineering RNA-protein complexes with different shapes for imaging and therapeutic applications. ACS NANO 2014; 8:8130-8140. [PMID: 25058166 DOI: 10.1021/nn502253c] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Molecular machines composed of RNA–protein (RNP) complexes may expand the fields of molecular robotics, nanomedicine, and synthetic biology. However, constructing and directly visualizing a functional RNP nanostructure to detect and control living cell function remains a challenge. Here we show that RNP nanostructures with modular functions can be designed and visualized at single-RNP resolution in real time. The RNP structural images collected in solution through high-speed atomic force microscopy showed that a single RNP interaction induces a conformational change in the RNA scaffold, which supports the nanostructure formation designed. The specific RNP interaction also improved RNA nanostructure stability in a serum-containing buffer. We developed and visualized functional RNPs (e.g., to detect human cancer cells or knockdown target genes) by attaching a protein or RNA module to the same RNA scaffold of an optimal size. The synthetic RNP architecture may provide alternative materials to detect and control functions in target mammalian cells.
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36
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Jiang H, Favaro E, Goulbourne CN, Rakowska PD, Hughes GM, Ryadnov MG, Fong LG, Young SG, Ferguson DJP, Harris AL, Grovenor CRM. Stable isotope imaging of biological samples with high resolution secondary ion mass spectrometry and complementary techniques. Methods 2014; 68:317-24. [PMID: 24556558 PMCID: PMC4222523 DOI: 10.1016/j.ymeth.2014.02.012] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2013] [Revised: 01/07/2014] [Accepted: 02/06/2014] [Indexed: 02/07/2023] Open
Abstract
Stable isotopes are ideal labels for studying biological processes because they have little or no effect on the biochemical properties of target molecules. The NanoSIMS is a tool that can image the distribution of stable isotope labels with up to 50 nm spatial resolution and with good quantitation. This combination of features has enabled several groups to undertake significant experiments on biological problems in the last decade. Combining the NanoSIMS with other imaging techniques also enables us to obtain not only chemical information but also the structural information needed to understand biological processes. This article describes the methodologies that we have developed to correlate atomic force microscopy and backscattered electron imaging with NanoSIMS experiments to illustrate the imaging of stable isotopes at molecular, cellular, and tissue scales. Our studies make it possible to address 3 biological problems: (1) the interaction of antimicrobial peptides with membranes; (2) glutamine metabolism in cancer cells; and (3) lipoprotein interactions in different tissues.
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Affiliation(s)
- H Jiang
- Materials Department, Oxford University, Oxford, UK.
| | - E Favaro
- Weatherall Institute of Molecular Medicine, Oxford University, Oxford, UK
| | - C N Goulbourne
- Department of Medicine, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, USA
| | - P D Rakowska
- National Physical Laboratory, Teddington, UK; Department of Chemistry, University College London, London, UK
| | - G M Hughes
- Materials Department, Oxford University, Oxford, UK
| | - M G Ryadnov
- National Physical Laboratory, Teddington, UK; School of Physics and Astronomy, University of Edinburgh, Edinburgh, UK
| | - L G Fong
- Department of Medicine, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, USA
| | - S G Young
- Department of Medicine, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, USA; Department of Human Genetics, University of California Los Angeles, Los Angeles, USA
| | - D J P Ferguson
- Nuffield Department of Clinical Laboratory Science, University of Oxford, John Radcliffe Hospital, Oxford, UK
| | - A L Harris
- Weatherall Institute of Molecular Medicine, Oxford University, Oxford, UK
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37
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Zhao WS, Wang J, Ma XJ, Yang Y, Liu Y, Huang LD, Fan YZ, Cheng XY, Chen HZ, Wang R, Yu Y. Relative motions between left flipper and dorsal fin domains favour P2X4 receptor activation. Nat Commun 2014; 5:4189. [PMID: 24943126 DOI: 10.1038/ncomms5189] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2014] [Accepted: 05/22/2014] [Indexed: 01/09/2023] Open
Abstract
Channel gating in response to extracellular ATP is a fundamental process for the physiological functions of P2X receptors. Here we identify coordinated allosteric changes in the left flipper (LF) and dorsal fin (DF) domains that couple ATP-binding to channel gating. Engineered disulphide crosslinking or zinc bridges between the LF and DF domains that constrain their relative motions significantly influence channel gating of P2X4 receptors, confirming the essential role of these allosteric changes. ATP-binding-induced alterations in interdomain hydrophobic interactions among I208, L217, V291 and the aliphatic chain of K193 correlate well with these coordinated relative movements. Mutations on those four residues lead to impaired or fully abolished channel activations of P2X4 receptors. Our data reveal that ATP-binding-induced altered interdomain hydrophobic interactions and the concomitant coordinated motions of LF and DF domains are allosteric events essential for the channel gating of P2X4 receptors.
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Affiliation(s)
- Wen-Shan Zhao
- 1] Institute of Medical Sciences and Department of Pharmacology, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China [2] Key Laboratory of Preclinical Study for New Drugs of Gansu Province, School of Basic Medical Sciences, Lanzhou University, Lanzhou 730000, China [3]
| | - Jin Wang
- 1] Institute of Medical Sciences and Department of Pharmacology, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China [2]
| | - Xiao-Juan Ma
- 1] Institute of Medical Sciences and Department of Pharmacology, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China [2] Key Laboratory of Preclinical Study for New Drugs of Gansu Province, School of Basic Medical Sciences, Lanzhou University, Lanzhou 730000, China [3]
| | - Yang Yang
- Institute of Medical Sciences and Department of Pharmacology, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Yan Liu
- Institute of Medical Sciences and Department of Pharmacology, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Li-Dong Huang
- Institute of Medical Sciences and Department of Pharmacology, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Ying-Zhe Fan
- Putuo District Center Hospital, Shanghai University of Chinese Traditional Medicine, Shanghai 200062, China
| | - Xiao-Yang Cheng
- Institute of Medical Sciences and Department of Pharmacology, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Hong-Zhuan Chen
- Institute of Medical Sciences and Department of Pharmacology, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Rui Wang
- Key Laboratory of Preclinical Study for New Drugs of Gansu Province, School of Basic Medical Sciences, Lanzhou University, Lanzhou 730000, China
| | - Ye Yu
- 1] Institute of Medical Sciences and Department of Pharmacology, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China [2] College of Bioscience and Biotechnology, Hunan Agricultural University, Changsha 410128, China
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38
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Pfreundschuh M, Martinez-Martin D, Mulvihill E, Wegmann S, Muller DJ. Multiparametric high-resolution imaging of native proteins by force-distance curve–based AFM. Nat Protoc 2014; 9:1113-30. [DOI: 10.1038/nprot.2014.070] [Citation(s) in RCA: 84] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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39
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Ando T, Uchihashi T, Scheuring S. Filming biomolecular processes by high-speed atomic force microscopy. Chem Rev 2014; 114:3120-88. [PMID: 24476364 PMCID: PMC4076042 DOI: 10.1021/cr4003837] [Citation(s) in RCA: 234] [Impact Index Per Article: 23.4] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2013] [Indexed: 12/21/2022]
Affiliation(s)
- Toshio Ando
- Department of Physics, and Bio-AFM Frontier
Research Center, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan
- CREST,
Japan Science and Technology Agency, 4-1-8 Honcho, Kawaguchi 332-0012, Japan
| | - Takayuki Uchihashi
- Department of Physics, and Bio-AFM Frontier
Research Center, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan
- CREST,
Japan Science and Technology Agency, 4-1-8 Honcho, Kawaguchi 332-0012, Japan
| | - Simon Scheuring
- U1006
INSERM/Aix-Marseille Université, Parc Scientifique et Technologique
de Luminy Bâtiment Inserm TPR2 bloc 5, 163 avenue de Luminy, 13288 Marseille Cedex 9, France
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40
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Sumino A, Yamamoto D, Iwamoto M, Dewa T, Oiki S. Gating-Associated Clustering-Dispersion Dynamics of the KcsA Potassium Channel in a Lipid Membrane. J Phys Chem Lett 2014; 5:578-84. [PMID: 26276612 DOI: 10.1021/jz402491t] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
The KcsA potassium channel is a prototypical channel of bacterial origin, and the mechanism underlying the pH-dependent gating has been studied extensively. With the high-resolution atomic force microscopy (AFM), we have resolved functional open and closed gates of the KcsA channel under the membrane-embedded condition. Here we surprisingly found that the pH-dependent gating of the KcsA channels was associated with clustering-dispersion dynamics. At neutral pH, the resting, closed channels were coalesced, forming nanoclusters. At acidic pH, the open-gated channels were dispersed as singly isolated channels. Time-lapse AFM revealed reversible clustering-dispersion transitions upon pH changes. At acidic equilibrium, a small fraction of the channels was nanoclustered, in which the gate was apparently closed. Thus, it is suggested that opening of the gate and the dispersion are tightly linked. The interplay between the intramolecular conformational change and the supramolecular clustering-dispersion dynamics provides insights into understanding of unprecedented functional cooperativity of channels.
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Affiliation(s)
- Ayumi Sumino
- †PRESTO, Japan Science and Technology Agency (JST), 4-1-8 Honcho, Kawaguchi-shi, Saitama 332-0012, Japan
- ‡Department of Molecular Physiology and Biophysics, Faculty of Medical Sciences, University of Fukui, 23-3 Matsuokashimoaizuki, Yoshida-gun, Fukui 910-1193, Japan
| | - Daisuke Yamamoto
- §Department of Applied Physics, Fukuoka University, 8-19-1 Nanakuma, Fukuoka 814-0180, Japan
| | - Masayuki Iwamoto
- ‡Department of Molecular Physiology and Biophysics, Faculty of Medical Sciences, University of Fukui, 23-3 Matsuokashimoaizuki, Yoshida-gun, Fukui 910-1193, Japan
| | - Takehisa Dewa
- ∥Department of Frontier Materials, Graduate School of Engineering, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya 466-8555, Japan
| | - Shigetoshi Oiki
- ‡Department of Molecular Physiology and Biophysics, Faculty of Medical Sciences, University of Fukui, 23-3 Matsuokashimoaizuki, Yoshida-gun, Fukui 910-1193, Japan
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41
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Bernier LP, Ase AR, Séguéla P. Post-translational regulation of P2X receptor channels: modulation by phospholipids. Front Cell Neurosci 2013; 7:226. [PMID: 24324400 PMCID: PMC3838964 DOI: 10.3389/fncel.2013.00226] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2013] [Accepted: 11/04/2013] [Indexed: 01/14/2023] Open
Abstract
P2X receptor channels mediate fast excitatory signaling by ATP and play major roles in sensory transduction, neuro-immune communication and inflammatory response. P2X receptors constitute a gene family of calcium-permeable ATP-gated cation channels therefore the regulation of P2X signaling is critical for both membrane potential and intracellular calcium homeostasis. Phosphoinositides (PIPn) are anionic signaling phospholipids that act as functional regulators of many types of ion channels. Direct PIPn binding was demonstrated for several ligand- or voltage-gated ion channels, however no generic motif emerged to accurately predict lipid-protein binding sites. This review presents what is currently known about the modulation of the different P2X subtypes by phospholipids and about critical determinants underlying their sensitivity to PIPn levels in the plasma membrane. All functional mammalian P2X subtypes tested, with the notable exception of P2X5, have been shown to be positively modulated by PIPn, i.e., homomeric P2X1, P2X2, P2X3, P2X4, and P2X7, as well as heteromeric P2X1/5 and P2X2/3 receptors. Based on various results reported on the aforementioned subtypes including mutagenesis of the prototypical PIPn-sensitive P2X4 and PIPn-insensitive P2X5 receptor subtypes, an increasing amount of functional, biochemical and structural evidence converges on the modulatory role of a short polybasic domain located in the proximal C-terminus of P2X subunits. This linear motif, semi-conserved in the P2X family, seems necessary and sufficient for encoding direct modulation of ATP-gated channels by PIPn. Furthermore, the physiological impact of the regulation of ionotropic purinergic responses by phospholipids on pain pathways was recently revealed in the context of native crosstalks between phospholipase C (PLC)-linked metabotropic receptors and P2X receptor channels in dorsal root ganglion sensory neurons and microglia.
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Affiliation(s)
- Louis-Philippe Bernier
- Department of Psychiatry, Brain Research Centre, University of British Columbia Vancouver, BC, Canada
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42
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Rokic MB, Stojilkovic SS. Two open states of P2X receptor channels. Front Cell Neurosci 2013; 7:215. [PMID: 24312007 PMCID: PMC3834609 DOI: 10.3389/fncel.2013.00215] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2013] [Accepted: 10/29/2013] [Indexed: 11/16/2022] Open
Abstract
The occupancy of the orthosteric ligand binding sites of P2X receptor (P2XR) channels causes the rapid opening of a small cation-permeable pore, followed by a gradual dilation that renders the pore permeable to large organic cations. Electrophysiologically, this phenomenon was shown using whole-cell current recording on P2X2R-, P2X2/X5R-, P2X4R- and P2X7R-expressing cells that were bathed in N-methyl-D-glucamine (NMDG+)-containing buffers in the presence and/or absence of small monovalent and divalent cations. The pore dilation of P2X4R and P2X7R caused a secondary current growth, whereas that of P2X2R showed a sustained kinetic coupling of dilation and desensitization, leading to receptor channel closure. The pore size of the P2X7R open and dilated states was estimated to be approximately 0.85 nm and greater than 1 nm, respectively. The P2XR pore dilation was also observed in intact cells by measurement of fluorescent dye uptake/release, application of polyethylene glycols of different sizes, and atomic force microscopy. However, pore dilation was not observed at the single channel level. Structural data describing the dilated state are not available, and the relevance of orthosteric and allosteric ligand interactions to pore dilation was not studied.
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Affiliation(s)
- Milos B Rokic
- Section on Cellular Signaling, Program in Developmental Neuroscience, The Eunice Kennedy Shiver National Institute of Child Health and Human Development, National Institutes of Health Bethesda, MD, USA
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43
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Rajendran A, Endo M, Sugiyama H. State-of-the-Art High-Speed Atomic Force Microscopy for Investigation of Single-Molecular Dynamics of Proteins. Chem Rev 2013; 114:1493-520. [DOI: 10.1021/cr300253x] [Citation(s) in RCA: 70] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Arivazhagan Rajendran
- Department
of Chemistry, Graduate School of Science, Kyoto University, Kitashirakawa-oiwakecho
Sakyo-ku, Kyoto 606-8502, Japan
| | - Masayuki Endo
- Institute
for Integrated Cell-Material Sciences (WPI-iCeMS), Kyoto University, Yoshida-ushinomiyacho,
Sakyo-ku, Kyoto 606-8501, Japan
- CREST, Japan Science and Technology Corporation (JST), Sanbancho, Chiyoda-ku, Tokyo 102-0075, Japan
| | - Hiroshi Sugiyama
- Department
of Chemistry, Graduate School of Science, Kyoto University, Kitashirakawa-oiwakecho
Sakyo-ku, Kyoto 606-8502, Japan
- Institute
for Integrated Cell-Material Sciences (WPI-iCeMS), Kyoto University, Yoshida-ushinomiyacho,
Sakyo-ku, Kyoto 606-8501, Japan
- CREST, Japan Science and Technology Corporation (JST), Sanbancho, Chiyoda-ku, Tokyo 102-0075, Japan
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44
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Pfreundschuh M, Hensen U, Müller DJ. Quantitative imaging of the electrostatic field and potential generated by a transmembrane protein pore at subnanometer resolution. NANO LETTERS 2013; 13:5585-5593. [PMID: 24079830 DOI: 10.1021/nl403232z] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Elucidating the mechanisms by which proteins translocate small molecules and ions through transmembrane pores and channels is of great interest in biology, medicine, and nanotechnology. However, the characterization of pore forming proteins in their native state lacks suitable methods that are capable of high-resolution imaging (~1 nm) while simultaneously mapping physical and chemical properties. Here we report how force-distance (FD) curve-based atomic force microscopy (AFM) imaging can be applied to image the native pore forming outer membrane protein F (OmpF) at subnanometer resolution and to quantify the electrostatic field and potential generated by the transmembrane pore. We further observe the electrostatic field and potential of the OmpF pore switching "on" and "off" in dependence of the electrolyte concentration. Because electrostatic field and potential select for charged molecules and ions and guide them to the transmembrane pore the insights are of fundamental importance to understand the pore function. These experimental results establish FD-based AFM as a unique tool to image biological systems to subnanometer resolution and to quantify their electrostatic properties.
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Affiliation(s)
- Moritz Pfreundschuh
- Department of Biosystems Science and Engineering, ETH Zurich , CH-4058 Basel, Switzerland
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45
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High-speed atomic force microscopy combined with inverted optical microscopy for studying cellular events. Sci Rep 2013; 3:2131. [PMID: 23823461 PMCID: PMC3701170 DOI: 10.1038/srep02131] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2013] [Accepted: 06/10/2013] [Indexed: 11/08/2022] Open
Abstract
A hybrid atomic force microscopy (AFM)-optical fluorescence microscopy is a powerful tool for investigating cellular morphologies and events. However, the slow data acquisition rates of the conventional AFM unit of the hybrid system limit the visualization of structural changes during cellular events. Therefore, high-speed AFM units equipped with an optical/fluorescence detection device have been a long-standing wish. Here we describe the implementation of high-speed AFM coupled with an optical fluorescence microscope. This was accomplished by developing a tip-scanning system, instead of a sample-scanning system, which operates on an inverted optical microscope. This novel device enabled the acquisition of high-speed AFM images of morphological changes in individual cells. Using this instrument, we conducted structural studies of living HeLa and 3T3 fibroblast cell surfaces. The improved time resolution allowed us to image dynamic cellular events.
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46
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Abstract
Directly observing individual protein molecules in action at high spatiotemporal resolution has long been a holy grail for biological science. This is because we long have had to infer how proteins function from the static snapshots of their structures and dynamic behavior of optical makers attached to the molecules. This limitation has recently been removed to a large extent by the materialization of high-speed atomic force microscopy (HS-AFM). HS-AFM allows us to directly visualize the structure dynamics and dynamic processes of biological molecules in physiological solutions, at subsecond to sub-100-ms temporal resolution, without disturbing their function. In fact, dynamically acting molecules such as myosin V walking on an actin filament and bacteriorhodopsin in response to light are successfully visualized. In this review, we first describe theoretical considerations for the highest possible imaging rate of this new microscope, and then highlight recent imaging studies. Finally, the current limitation and future challenges to explore are described.
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Affiliation(s)
- Toshio Ando
- Department of Physics, Kanazawa University, Kanazawa 920-1192, Japan.
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47
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Watanabe H, Uchihashi T, Kobashi T, Shibata M, Nishiyama J, Yasuda R, Ando T. Wide-area scanner for high-speed atomic force microscopy. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2013; 84:053702. [PMID: 23742553 DOI: 10.1063/1.4803449] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
High-speed atomic force microscopy (HS-AFM) has recently been established. The dynamic processes and structural dynamics of protein molecules in action have been successfully visualized using HS-AFM. However, its maximum scan ranges in the X- and Y-directions have been limited to ~1 μm and ~4 μm, respectively, making it infeasible to observe the dynamics of much larger samples, including live cells. Here, we develop a wide-area scanner with a maximum XY scan range of ~46 × 46 μm(2) by magnifying the displacements of stack piezoelectric actuators using a leverage mechanism. Mechanical vibrations produced by fast displacement of the X-scanner are suppressed by a combination of feed-forward inverse compensation and the use of triangular scan signals with rounded vertices. As a result, the scan speed in the X-direction reaches 6.3 mm/s even for a scan size as large as ~40 μm. The nonlinearity of the X- and Y-piezoelectric actuators' displacements that arises from their hysteresis is eliminated by polynomial-approximation-based open-loop control. The interference between the X- and Y-scanners is also eliminated by the same technique. The usefulness of this wide-area scanner is demonstrated by video imaging of dynamic processes in live bacterial and eukaryotic cells.
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Affiliation(s)
- Hiroki Watanabe
- Department of Physics, College of Science and Engineering, Kanazawa University, Kanazawa 920-1192, Japan
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48
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Sun C, Heid ME, Keyel PA, Salter RD. The second transmembrane domain of P2X7 contributes to dilated pore formation. PLoS One 2013; 8:e61886. [PMID: 23613968 PMCID: PMC3629090 DOI: 10.1371/journal.pone.0061886] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2012] [Accepted: 03/18/2013] [Indexed: 01/07/2023] Open
Abstract
Activation of the purinergic receptor P2X7 leads to the cellular permeability of low molecular weight cations. To determine which domains of P2X7 are necessary for this permeability, we exchanged either the C-terminus or portions of the second transmembrane domain (TM2) with those in P2X1 or P2X4. Replacement of the C-terminus of P2X7 with either P2X1 or P2X4 prevented surface expression of the chimeric receptor. Similarly, chimeric P2X7 containing TM2 from P2X1 or P2X4 had reduced surface expression and no permeability to cationic dyes. Exchanging the N-terminal 10 residues or C-terminal 14 residues of the P2X7 TM2 with the corresponding region of P2X1 TM2 partially restored surface expression and limited pore permeability. To further probe TM2 structure, we replaced single residues in P2X7 TM2 with those in P2X1 or P2X4. We identified multiple substitutions that drastically changed pore permeability without altering surface expression. Three substitutions (Q332P, Y336T, and Y343L) individually reduced pore formation as indicated by decreased dye uptake and also reduced membrane blebbing in response to ATP exposure. Three others substitutions, V335T, S342G, and S342A each enhanced dye uptake, membrane blebbing and cell death. Our results demonstrate a critical role for the TM2 domain of P2X7 in receptor function, and provide a structural basis for differences between purinergic receptors.
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Affiliation(s)
- Chengqun Sun
- Department of Immunology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States of America
| | - Michelle E. Heid
- Department of Immunology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States of America
| | - Peter A. Keyel
- Department of Immunology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States of America
| | - Russell D. Salter
- Department of Immunology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States of America
- * E-mail:
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Whited AM, Park PSH. Atomic force microscopy: a multifaceted tool to study membrane proteins and their interactions with ligands. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2013; 1838:56-68. [PMID: 23603221 DOI: 10.1016/j.bbamem.2013.04.011] [Citation(s) in RCA: 83] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2013] [Revised: 03/22/2013] [Accepted: 04/09/2013] [Indexed: 01/31/2023]
Abstract
Membrane proteins are embedded in lipid bilayers and facilitate the communication between the external environment and the interior of the cell. This communication is often mediated by the binding of ligands to the membrane protein. Understanding the nature of the interaction between a ligand and a membrane protein is required to both understand the mechanism of action of these proteins and for the development of novel pharmacological drugs. The highly hydrophobic nature of membrane proteins and the requirement of a lipid bilayer for native function have hampered the structural and molecular characterizations of these proteins under physiologically relevant conditions. Atomic force microscopy offers a solution to studying membrane proteins and their interactions with ligands under physiologically relevant conditions and can provide novel insights about the nature of these critical molecular interactions that facilitate cellular communication. In this review, we provide an overview of the atomic force microscopy technique and discuss its application in the study of a variety of questions related to the interaction between a membrane protein and a ligand. This article is part of a Special Issue entitled: Structural and biophysical characterization of membrane protein-ligand binding.
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Affiliation(s)
- Allison M Whited
- Department of Ophthalmology and Visual Sciences, Case Western Reserve University, Cleveland, OH 44106, USA
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Baranovic J, Ramanujan CS, Kasai N, Midgett CR, Madden DR, Torimitsu K, Ryan JF. Reconstitution of homomeric GluA2(flop) receptors in supported lipid membranes: functional and structural properties. J Biol Chem 2013; 288:8647-8657. [PMID: 23382380 DOI: 10.1074/jbc.m112.422105] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
AMPA receptors (AMPARs) are glutamate-gated ion channels ubiquitous in the vertebrate central nervous system, where they mediate fast excitatory neurotransmission and act as molecular determinants of memory formation and learning. Together with detailed analyses of individual AMPAR domains, structural studies of full-length AMPARs by electron microscopy and x-ray crystallography have provided important insights into channel assembly and function. However, the correlation between the structure and functional states of the channel remains ambiguous particularly because these functional states can be assessed only with the receptor bound within an intact lipid bilayer. To provide a basis for investigating AMPAR structure in a membrane environment, we developed an optimized reconstitution protocol using a receptor whose structure has previously been characterized by electron microscopy. Single-channel recordings of reconstituted homomeric GluA2(flop) receptors recapitulate key electrophysiological parameters of the channels expressed in native cellular membranes. Atomic force microscopy studies of the reconstituted samples provide high-resolution images of membrane-embedded full-length AMPARs at densities comparable to those in postsynaptic membranes. The data demonstrate the effect of protein density on conformational flexibility and dimensions of the receptors and provide the first structural characterization of functional membrane-embedded AMPARs, thus laying the foundation for correlated structure-function analyses of the predominant mediators of excitatory synaptic signals in the brain.
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Affiliation(s)
- Jelena Baranovic
- Department of Physics, University of Oxford, Oxford OX1 3PU, United Kingdom.
| | | | - Nahoko Kasai
- NTT Basic Research Laboratories, Atsugi, Kanagawa 243-0198, Japan
| | - Charles R Midgett
- Department of Biochemistry, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire 03755-1404
| | - Dean R Madden
- Department of Biochemistry, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire 03755-1404
| | | | - John F Ryan
- Department of Physics, University of Oxford, Oxford OX1 3PU, United Kingdom
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