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Stover L, Zhu Y, Schrecke S, Laganowsky A. TREK2 Lipid Binding Preferences Revealed by Native Mass Spectrometry. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2024; 35:1516-1522. [PMID: 38843438 PMCID: PMC11228984 DOI: 10.1021/jasms.4c00112] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2024] [Revised: 05/24/2024] [Accepted: 05/28/2024] [Indexed: 07/04/2024]
Abstract
TREK2, a two-pore domain potassium channel, is recognized for its regulation by various stimuli, including lipids. While previous members of the TREK subfamily, TREK1 and TRAAK, have been investigated to elucidate their lipid affinity and selectivity, TREK2 has not been similarly studied in this regard. Our findings indicate that while TRAAK and TREK2 exhibit similarities in terms of electrostatics and share an overall structural resemblance, there are notable distinctions in their interaction with lipids. Specifically, SAPI(4,5)P2,1-stearoyl-2-arachidonoyl-sn-glycero-3-phospho-(1'-myo-inositol-4',5'-bisphosphate) exhibits a strong affinity for TREK2, surpassing that of dOPI(4,5)P2,1,2-dioleoyl-sn-glycero-3-phospho-(1'-myo-inositol-4',5'-bisphosphate), which differs in its acyl chains. TREK2 displays lipid binding preferences not only for the headgroup of lipids but also toward the acyl chains. Functional studies draw a correlation for lipid binding affinity and activity of the channel. These findings provide important insight into elucidating the molecular prerequisites for specific lipid binding to TREK2 important for function.
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Affiliation(s)
- Lauren Stover
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
| | - Yun Zhu
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
| | - Samantha Schrecke
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
| | - Arthur Laganowsky
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
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2
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Bechard E, Arel E, Bride J, Louradour J, Bussy X, Elloumi A, Vigor C, Soule P, Oger C, Galano JM, Durand T, Le Guennec JY, Moha-Ou-Maati H, Demion M. Activation of hTREK-1 by polyunsaturated fatty acids involves direct interaction. Sci Rep 2024; 14:15244. [PMID: 38956407 PMCID: PMC11220079 DOI: 10.1038/s41598-024-66192-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2023] [Accepted: 06/28/2024] [Indexed: 07/04/2024] Open
Abstract
TREK-1 is a mechanosensitive channel activated by polyunsaturated fatty acids (PUFAs). Its activation is supposed to be linked to changes in membrane tension following PUFAs insertion. Here, we compared the effect of 11 fatty acids and ML402 on TREK-1 channel activation using the whole cell and the inside-out configurations of the patch-clamp technique. Firstly, TREK-1 activation by PUFAs is variable and related to the variable constitutive activity of TREK-1. We observed no correlation between TREK-1 activation and acyl chain length or number of double bonds suggesting that the bilayer-couple hypothesis cannot explain by itself the activation of TREK-1 by PUFAs. The membrane fluidity measurement is not modified by PUFAs at 10 µM. The spectral shift analysis in TREK-1-enriched microsomes indicates a KD,TREK1 at 44 µM of C22:6 n-3. PUFAs display the same activation and reversible kinetics than the direct activator ML402 and activate TREK-1 in both whole-cell and inside-out configurations of patch-clamp suggesting that the binding site of PUFAs is accessible from both sides of the membrane, as for ML402. Finally, we proposed a two steps mechanism: first, insertion into the membrane, with no fluidity or curvature modifications at 10 µM, and then interaction with TREK-1 channel to open it.
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Affiliation(s)
- Emilie Bechard
- PhyMedExp, Université de Montpellier, Inserm U1046, UMR CNRS 9412, CHU Arnaud de Villeneuve, Bâtiment Craste de Paulet, 370 Avenue du Doyen Gaston Giraud, 34290, Montpellier Cedex 05, France
| | - Elodie Arel
- PhyMedExp, Université de Montpellier, Inserm U1046, UMR CNRS 9412, CHU Arnaud de Villeneuve, Bâtiment Craste de Paulet, 370 Avenue du Doyen Gaston Giraud, 34290, Montpellier Cedex 05, France
| | - Jamie Bride
- PhyMedExp, Université de Montpellier, Inserm U1046, UMR CNRS 9412, CHU Arnaud de Villeneuve, Bâtiment Craste de Paulet, 370 Avenue du Doyen Gaston Giraud, 34290, Montpellier Cedex 05, France
| | - Julien Louradour
- PhyMedExp, Université de Montpellier, Inserm U1046, UMR CNRS 9412, CHU Arnaud de Villeneuve, Bâtiment Craste de Paulet, 370 Avenue du Doyen Gaston Giraud, 34290, Montpellier Cedex 05, France
| | - Xavier Bussy
- PhyMedExp, Université de Montpellier, Inserm U1046, UMR CNRS 9412, CHU Arnaud de Villeneuve, Bâtiment Craste de Paulet, 370 Avenue du Doyen Gaston Giraud, 34290, Montpellier Cedex 05, France
| | - Anis Elloumi
- IBMM, Université de Montpellier, UMR CNRS 5247, ENSCM, Montpellier, France
| | - Claire Vigor
- IBMM, Université de Montpellier, UMR CNRS 5247, ENSCM, Montpellier, France
| | | | - Camille Oger
- IBMM, Université de Montpellier, UMR CNRS 5247, ENSCM, Montpellier, France
| | - Jean-Marie Galano
- IBMM, Université de Montpellier, UMR CNRS 5247, ENSCM, Montpellier, France
| | - Thierry Durand
- IBMM, Université de Montpellier, UMR CNRS 5247, ENSCM, Montpellier, France
| | - Jean-Yves Le Guennec
- PhyMedExp, Université de Montpellier, Inserm U1046, UMR CNRS 9412, CHU Arnaud de Villeneuve, Bâtiment Craste de Paulet, 370 Avenue du Doyen Gaston Giraud, 34290, Montpellier Cedex 05, France
| | - Hamid Moha-Ou-Maati
- IGF, Université de Montpellier, UMR CNRS 5203, Inserm 1191, Montpellier, France
- INM, Inserm U1298, Montpellier, France
| | - Marie Demion
- PhyMedExp, Université de Montpellier, Inserm U1046, UMR CNRS 9412, CHU Arnaud de Villeneuve, Bâtiment Craste de Paulet, 370 Avenue du Doyen Gaston Giraud, 34290, Montpellier Cedex 05, France.
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3
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Michelucci A, Catacuzzeno L. Piezo1, the new actor in cell volume regulation. Pflugers Arch 2024; 476:1023-1039. [PMID: 38581527 PMCID: PMC11166825 DOI: 10.1007/s00424-024-02951-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2024] [Revised: 02/29/2024] [Accepted: 03/20/2024] [Indexed: 04/08/2024]
Abstract
All animal cells control their volume through a complex set of mechanisms, both to counteract osmotic perturbations of the environment and to enable numerous vital biological processes, such as proliferation, apoptosis, and migration. The ability of cells to adjust their volume depends on the activity of ion channels and transporters which, by moving K+, Na+, and Cl- ions across the plasma membrane, generate the osmotic gradient that drives water in and out of the cell. In 2010, Patapoutian's group identified a small family of evolutionarily conserved, Ca2+-permeable mechanosensitive channels, Piezo1 and Piezo2, as essential components of the mechanically activated current that mediates mechanotransduction in vertebrates. Piezo1 is expressed in several tissues and its opening is promoted by a wide range of mechanical stimuli, including membrane stretch/deformation and osmotic stress. Piezo1-mediated Ca2+ influx is used by the cell to convert mechanical forces into cytosolic Ca2+ signals that control diverse cellular functions such as migration and cell death, both dependent on changes in cell volume and shape. The crucial role of Piezo1 in the regulation of cell volume was first demonstrated in erythrocytes, which need to reduce their volume to pass through narrow capillaries. In HEK293 cells, increased expression of Piezo1 was found to enhance the regulatory volume decrease (RVD), the process whereby the cell re-establishes its original volume after osmotic shock-induced swelling, and it does so through Ca2+-dependent modulation of the volume-regulated anion channels. More recently we reported that Piezo1 controls the RVD in glioblastoma cells via the modulation of Ca2+-activated K+ channels. To date, however, the mechanisms through which this mechanosensitive channel controls cell volume and maintains its homeostasis have been poorly investigated and are still far from being understood. The present review aims to provide a broad overview of the literature discussing the recent advances on this topic.
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Affiliation(s)
- A Michelucci
- Department of Chemistry, Biology and Biotechnology, University of Perugia, 06123, Perugia, Italy.
| | - L Catacuzzeno
- Department of Chemistry, Biology and Biotechnology, University of Perugia, 06123, Perugia, Italy.
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4
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Türkaydin B, Schewe M, Riel EB, Schulz F, Biedermann J, Baukrowitz T, Sun H. Atomistic mechanism of coupling between cytosolic sensor domain and selectivity filter in TREK K2P channels. Nat Commun 2024; 15:4628. [PMID: 38821927 PMCID: PMC11143257 DOI: 10.1038/s41467-024-48823-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2023] [Accepted: 05/15/2024] [Indexed: 06/02/2024] Open
Abstract
The two-pore domain potassium (K2P) channels TREK-1 and TREK-2 link neuronal excitability to a variety of stimuli including mechanical force, lipids, temperature and phosphorylation. This regulation involves the C-terminus as a polymodal stimulus sensor and the selectivity filter (SF) as channel gate. Using crystallographic up- and down-state structures of TREK-2 as a template for full atomistic molecular dynamics (MD) simulations, we reveal that the SF in down-state undergoes inactivation via conformational changes, while the up-state structure maintains a stable and conductive SF. This suggests an atomistic mechanism for the low channel activity previously assigned to the down state, but not evident from the crystal structure. Furthermore, experimentally by using (de-)phosphorylation mimics and chemically attaching lipid tethers to the proximal C-terminus (pCt), we confirm the hypothesis that moving the pCt towards the membrane induces the up-state. Based on MD simulations, we propose two gating pathways by which movement of the pCt controls the stability (i.e., conductivity) of the filter gate. Together, these findings provide atomistic insights into the SF gating mechanism and the physiological regulation of TREK channels by phosphorylation.
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Affiliation(s)
- Berke Türkaydin
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Berlin, Germany
- Insitute of Chemistry, Technical University of Berlin, Berlin, Germany
| | - Marcus Schewe
- Institute of Physiology, Kiel University, Kiel, Germany.
| | - Elena Barbara Riel
- Institute of Physiology, Kiel University, Kiel, Germany
- Department of Anesthesiology, Weill Cornell Medical College, New York, USA
| | | | - Johann Biedermann
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Berlin, Germany
| | | | - Han Sun
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Berlin, Germany.
- Insitute of Chemistry, Technical University of Berlin, Berlin, Germany.
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5
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Li Z, Lin X, Wei J, Shan X, Wu Z, Luo Y, Wang Y, Feng Y, Ren T, Song Z, Wang F, Zhang K. An Artificial LiSiO x Nociceptor with Neural Blockade and Self-Protection Abilities. ACS APPLIED MATERIALS & INTERFACES 2024; 16:19205-19213. [PMID: 38591860 DOI: 10.1021/acsami.4c01406] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/10/2024]
Abstract
An artificial nociceptor, as a critical and special bionic receptor, plays a key role in a bioelectronic device that detects stimuli and provides warnings. However, fully exploiting bioelectronic applications remains a major challenge due to the lack of the methods of implementing basic nociceptor functions and nociceptive blockade in a single device. In this work, we developed a Pt/LiSiOx/TiN artificial nociceptor. It had excellent stability under the 104 endurance test with pulse stimuli and exhibited a significant threshold current of 1 mA with 1 V pulse stimuli. Other functions such as relaxation, inadaptation, and sensitization were all realized in a single device. Also, the pain blockade function was first achieved in this nociceptor with over a 25% blocking degree, suggesting a self-protection function. More importantly, an obvious depression was activated by a stimulus over 1.6 V due to the cooperative effects of both lithium ions and oxygen ions in LiSiOx and the dramatic accumulation of Joule heat. The conducting channel ruptured partially under sequential potentiation, thus achieving nociceptive blockade, besides basic functions in one single nociceptor, which was rarely reported. These results provided important guidelines for constructing high-performance memristor-based artificial nociceptors and opened up an alternative approach to the realization of bioelectronic systems for artificial intelligence.
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Affiliation(s)
- Zewen Li
- Tianjin Key Laboratory of Film Electronic & Communication Devices, School of Integrated Circuit Science and Engineering, Tianjin University of Technology, Tianjin 300384, China
| | - Xin Lin
- School of Materials Science and Engineering, Tianjin University of Technology, Tianjin 300384, China
| | - Junqing Wei
- Tianjin Key Laboratory of Film Electronic & Communication Devices, School of Integrated Circuit Science and Engineering, Tianjin University of Technology, Tianjin 300384, China
| | - Xin Shan
- School of Materials Science and Engineering, Tianjin University of Technology, Tianjin 300384, China
| | - Zeyu Wu
- Tianjin Key Laboratory of Film Electronic & Communication Devices, School of Integrated Circuit Science and Engineering, Tianjin University of Technology, Tianjin 300384, China
| | - Yu Luo
- Tianjin Key Laboratory of Film Electronic & Communication Devices, School of Integrated Circuit Science and Engineering, Tianjin University of Technology, Tianjin 300384, China
| | - Yuchan Wang
- Tianjin Key Laboratory of Film Electronic & Communication Devices, School of Integrated Circuit Science and Engineering, Tianjin University of Technology, Tianjin 300384, China
| | - Yulin Feng
- Key Laboratory of the Ministry of Education for Optoelectronic Measurement Technology and Instrument, Beijing Information Science and Technology University, Beijing 100192, China
| | - Tianling Ren
- Beijing National Research Center for Information Science and Technology, Institute of Microelectronics, Tsinghua University, Beijing 100084, China
| | - Zhitang Song
- Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai 200050, China
| | - Fang Wang
- Tianjin Key Laboratory of Film Electronic & Communication Devices, School of Integrated Circuit Science and Engineering, Tianjin University of Technology, Tianjin 300384, China
| | - Kailiang Zhang
- Tianjin Key Laboratory of Film Electronic & Communication Devices, School of Integrated Circuit Science and Engineering, Tianjin University of Technology, Tianjin 300384, China
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6
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Zhu Y, Yun SD, Zhang T, Chang JY, Stover L, Laganowsky A. Native mass spectrometry of proteoliposomes containing integral and peripheral membrane proteins. Chem Sci 2023; 14:14243-14255. [PMID: 38098719 PMCID: PMC10718073 DOI: 10.1039/d3sc04938h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Accepted: 11/18/2023] [Indexed: 12/17/2023] Open
Abstract
Cellular membranes are critical to the function of membrane proteins, whether they are associated (peripheral) or embedded (integral) within the bilayer. While detergents have contributed to our understanding of membrane protein structure and function, there remains challenges in characterizing protein-lipid interactions within the context of an intact membrane. Here, we developed a method to prepare proteoliposomes for native mass spectrometry (MS) studies. We first use native MS to detect the encapsulation of soluble proteins within liposomes. We then find the peripheral Gβ1γ2 complex associated with the membrane can be ejected and analyzed using native MS. Four different integral membrane proteins (AmtB, AqpZ, TRAAK, and TREK2), all of which have previously been characterized in detergent, eject from the proteoliposomes as intact complexes bound to lipids that have been shown to tightly associate in detergent, drawing a correlation between the two approaches. We also show the utility of more complex lipid environments, such as a brain polar lipid extract, and show TRAAK ejects from liposomes of this extract bound to lipids. These findings underscore the capability to eject protein complexes from membranes bound to both lipids and metal ions, and this approach will be instrumental in the identification of key protein-lipid interactions.
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Affiliation(s)
- Yun Zhu
- Department of Chemistry, Texas A&M University College Station TX 77843 USA
| | - Sangho D Yun
- Department of Chemistry, Texas A&M University College Station TX 77843 USA
| | - Tianqi Zhang
- Department of Chemistry, Texas A&M University College Station TX 77843 USA
| | - Jing-Yuan Chang
- Department of Chemistry, Texas A&M University College Station TX 77843 USA
| | - Lauren Stover
- Department of Chemistry, Texas A&M University College Station TX 77843 USA
| | - Arthur Laganowsky
- Department of Chemistry, Texas A&M University College Station TX 77843 USA
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7
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Hori A, Fukazawa A, Katanosaka K, Mizuno M, Hotta N. Mechanosensitive channels in the mechanical component of the exercise pressor reflex. Auton Neurosci 2023; 250:103128. [PMID: 37925831 DOI: 10.1016/j.autneu.2023.103128] [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: 06/18/2023] [Revised: 10/24/2023] [Accepted: 10/26/2023] [Indexed: 11/07/2023]
Abstract
The cardiovascular response is appropriately regulated during exercise to meet the metabolic demands of the active muscles. The exercise pressor reflex is a neural feedback mechanism through thin-fiber muscle afferents activated by mechanical and metabolic stimuli in the active skeletal muscles. The mechanical component of this reflex is referred to as skeletal muscle mechanoreflex. Its initial step requires mechanotransduction mediated by mechanosensors, which convert mechanical stimuli into biological signals. Recently, various mechanosensors have been identified, and their contributions to muscle mechanoreflex have been actively investigated. Nevertheless, the mechanosensitive channels responsible for this muscular reflex remain largely unknown. This review discusses progress in our understanding of muscle mechanoreflex under healthy conditions, focusing on mechanosensitive channels.
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Affiliation(s)
- Amane Hori
- College of Life and Health Sciences, Chubu University, 1200 Matsumoto-cho, Kasugai, Aichi 487-8501, Japan; Japan Society for the Promotion of Science, 5-3-1 Kojimachi, Chiyoda-ku, Tokyo 102-8472, Japan; Department of Applied Clinical Research, UT Southwestern Medical Center, Dallas, TX 75390-9174, USA
| | - Ayumi Fukazawa
- Japan Society for the Promotion of Science, 5-3-1 Kojimachi, Chiyoda-ku, Tokyo 102-8472, Japan; Department of Applied Clinical Research, UT Southwestern Medical Center, Dallas, TX 75390-9174, USA
| | - Kimiaki Katanosaka
- College of Life and Health Sciences, Chubu University, 1200 Matsumoto-cho, Kasugai, Aichi 487-8501, Japan
| | - Masaki Mizuno
- Department of Applied Clinical Research, UT Southwestern Medical Center, Dallas, TX 75390-9174, USA
| | - Norio Hotta
- College of Life and Health Sciences, Chubu University, 1200 Matsumoto-cho, Kasugai, Aichi 487-8501, Japan.
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8
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Arrowsmith S. Multiple pregnancies, the myometrium and the role of mechanical factors in the timing of labour. Curr Res Physiol 2023; 6:100105. [PMID: 38107788 PMCID: PMC10724211 DOI: 10.1016/j.crphys.2023.100105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Revised: 07/17/2023] [Accepted: 08/23/2023] [Indexed: 12/19/2023] Open
Abstract
Multiple pregnancy remains a relatively common occurrence, but it is associated with increased risks of adverse outcomes for the mother and her babies and presents unique challenges to healthcare providers. This review will briefly discuss multiple pregnancies, their aetiology and their problems, including preterm birth, before reviewing the processes leading to normal labour onset and how they may be different in a multiple pregnancy. The mechanisms by which mechanical factors i.e., uterine distension or 'stretch' contribute to uterine excitability and the timing of labour onset will be the major focus, and how over distention may pre-dispose multiple pregnancies to preterm birth. This includes current thinking around the role of mechano (stretch) sensitive ion channels in the myometrium and changes to other important regulators of excitability and contraction which have been identified from studies using in vitro and in vivo models of uterine stretch. Physiological stimuli arising from the fetus(es) and placenta(s) will also be discussed. In reviewing what we know about the myometrium in multiple pregnancy in humans, the focus will be on twin pregnancy as it is the most common type of multiple pregnancy and has been the most studied.
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Affiliation(s)
- Sarah Arrowsmith
- Department of Life Sciences, Manchester Metropolitan University, John Dalton Building, Chester Street, Manchester, M1 5GD, UK
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9
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Zhu Y, Odenkirk MT, Qiao P, Zhang T, Schrecke S, Zhou M, Marty MT, Baker ES, Laganowsky A. Combining native mass spectrometry and lipidomics to uncover specific membrane protein-lipid interactions from natural lipid sources. Chem Sci 2023; 14:8570-8582. [PMID: 37593000 PMCID: PMC10430552 DOI: 10.1039/d3sc01482g] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Accepted: 07/19/2023] [Indexed: 08/19/2023] Open
Abstract
While it is known that lipids play an essential role in regulating membrane protein structure and function, it remains challenging to identify specific protein-lipid interactions. Here, we present an innovative approach that combines native mass spectrometry (MS) and lipidomics to identify lipids retained by membrane proteins from natural lipid extracts. Our results reveal that the bacterial ammonia channel (AmtB) enriches specific cardiolipin (CDL) and phosphatidylethanolamine (PE) from natural headgroup extracts. When the two extracts are mixed, AmtB retains more species, wherein selectivity is tuned to bias headgroup selection. Using a series of natural headgroup extracts, we show TRAAK, a two-pore domain K+ channel (K2P), retains specific acyl chains that is independent of the headgroup. A brain polar lipid extract was then combined with the K2Ps, TRAAK and TREK2, to understand lipid specificity. More than a hundred lipids demonstrated affinity for each protein, and both channels were found to retain specific fatty acids and lysophospholipids known to stimulate channel activity, even after several column washes. Natural lipid extracts provide the unique opportunity to not only present natural lipid diversity to purified membrane proteins but also identify lipids that may be important for membrane protein structure and function.
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Affiliation(s)
- Yun Zhu
- Department of Chemistry, Texas A&M University College Station TX 77843 USA
| | - Melanie T Odenkirk
- Department of Chemistry, North Carolina State University Raleigh NC 27695 USA
| | - Pei Qiao
- Department of Chemistry, Texas A&M University College Station TX 77843 USA
| | - Tianqi Zhang
- Department of Chemistry, Texas A&M University College Station TX 77843 USA
| | - Samantha Schrecke
- Department of Chemistry, Texas A&M University College Station TX 77843 USA
| | - Ming Zhou
- Verna and Marrs McLean Department of Biochemistry and Molecular Pharmacology, Baylor College of Medicine Houston TX 77030 USA
| | - Michael T Marty
- Department of Chemistry and Biochemistry, The University of Arizona Tucson AZ 85721 USA
| | - Erin S Baker
- Department of Chemistry, University of North Carolina Chapel Hill NC 27514 USA
| | - Arthur Laganowsky
- Department of Chemistry, Texas A&M University College Station TX 77843 USA
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10
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Davis MJ, Earley S, Li YS, Chien S. Vascular mechanotransduction. Physiol Rev 2023; 103:1247-1421. [PMID: 36603156 PMCID: PMC9942936 DOI: 10.1152/physrev.00053.2021] [Citation(s) in RCA: 53] [Impact Index Per Article: 53.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Revised: 09/26/2022] [Accepted: 10/04/2022] [Indexed: 01/07/2023] Open
Abstract
This review aims to survey the current state of mechanotransduction in vascular smooth muscle cells (VSMCs) and endothelial cells (ECs), including their sensing of mechanical stimuli and transduction of mechanical signals that result in the acute functional modulation and longer-term transcriptomic and epigenetic regulation of blood vessels. The mechanosensors discussed include ion channels, plasma membrane-associated structures and receptors, and junction proteins. The mechanosignaling pathways presented include the cytoskeleton, integrins, extracellular matrix, and intracellular signaling molecules. These are followed by discussions on mechanical regulation of transcriptome and epigenetics, relevance of mechanotransduction to health and disease, and interactions between VSMCs and ECs. Throughout this review, we offer suggestions for specific topics that require further understanding. In the closing section on conclusions and perspectives, we summarize what is known and point out the need to treat the vasculature as a system, including not only VSMCs and ECs but also the extracellular matrix and other types of cells such as resident macrophages and pericytes, so that we can fully understand the physiology and pathophysiology of the blood vessel as a whole, thus enhancing the comprehension, diagnosis, treatment, and prevention of vascular diseases.
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Affiliation(s)
- Michael J Davis
- Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, Missouri
| | - Scott Earley
- Department of Pharmacology, University of Nevada, Reno, Nevada
| | - Yi-Shuan Li
- Department of Bioengineering, University of California, San Diego, California
- Institute of Engineering in Medicine, University of California, San Diego, California
| | - Shu Chien
- Department of Bioengineering, University of California, San Diego, California
- Institute of Engineering in Medicine, University of California, San Diego, California
- Department of Medicine, University of California, San Diego, California
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11
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Ullrich J, Ohlhoff C, Dondapati SK, Zemella A, Kubick S. Evaluation of the Ion Channel Assembly in a Eukaryotic Cell-Free System Focusing on Two-Pore Domain Potassium Channels K 2P. Int J Mol Sci 2023; 24:6299. [PMID: 37047271 PMCID: PMC10094441 DOI: 10.3390/ijms24076299] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Revised: 03/20/2023] [Accepted: 03/24/2023] [Indexed: 03/30/2023] Open
Abstract
Oligomeric ion channels are abundant in nature. However, the recombinant expression in cell culture-based systems remains tedious and challenging due to negative side effects, limiting the understanding of their role in health and disease. Accordingly, in this work, we demonstrate the cell-free synthesis (CFS) as an alternative platform to study the assembly of two-pore domain potassium channels (K2P) within endogenous endoplasmic reticulum-derived microsomes. Exploiting the open nature of CFS, we investigate the cotranslational translocation of TREK-2 into the microsomes and suggest a cotranslational assembly with typical single-channel behavior in planar lipid-bilayer electrophysiology. The heteromeric assembly of K2P channels is a contentious matter, accordingly we prove the successful assembly of TREK-2 with TWIK-1 using a biomolecular fluorescence complementation assay, Western blot analysis and autoradiography. The results demonstrate that TREK-2 homodimer assembly is the initial step, followed by heterodimer formation with the nascent TWIK-1, providing evidence of the intergroup heterodimerization of TREK-2 and TWIK-1 in eukaryotic CFS. Since K2P channels are involved in various pathophysiological conditions, including pain and nociception, CFS paves the way for in-depth functional studies and related pharmacological interventions. This study highlights the versatility of the eukaryotic CFS platform for investigating ion channel assembly in a native-like environment.
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Affiliation(s)
- Jessica Ullrich
- Fraunhofer Institute for Cell Therapy and Immunology (IZI), Branch Bioanalytics and Bioprocesses (IZI-BB), Am Mühlenberg 13, 14476 Potsdam, Germany
- Institute of Biotechnology, Technische Universität Berlin, Straße des 17. Juni 135, 10623 Berlin, Germany
| | - Carsten Ohlhoff
- Fraunhofer Institute for Cell Therapy and Immunology (IZI), Branch Bioanalytics and Bioprocesses (IZI-BB), Am Mühlenberg 13, 14476 Potsdam, Germany
- Institute of Biotechnology, Technische Universität Berlin, Straße des 17. Juni 135, 10623 Berlin, Germany
| | - Srujan Kumar Dondapati
- Fraunhofer Institute for Cell Therapy and Immunology (IZI), Branch Bioanalytics and Bioprocesses (IZI-BB), Am Mühlenberg 13, 14476 Potsdam, Germany
| | - Anne Zemella
- Fraunhofer Institute for Cell Therapy and Immunology (IZI), Branch Bioanalytics and Bioprocesses (IZI-BB), Am Mühlenberg 13, 14476 Potsdam, Germany
| | - Stefan Kubick
- Fraunhofer Institute for Cell Therapy and Immunology (IZI), Branch Bioanalytics and Bioprocesses (IZI-BB), Am Mühlenberg 13, 14476 Potsdam, Germany
- Institute of Chemistry and Biochemistry, Freie Universität Berlin, Thielallee 63, 14195 Berlin, Germany
- Faculty of Health Sciences, Joint Faculty of the Brandenburg University of Technology Cottbus-Senftenberg, the Brandenburg Medical School Theodor Fontane and the University of Potsdam, 14476 Potsdam, Germany
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12
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Synergistic effects of agonists and two-pore-domain potassium channels on secretory responses of human pancreatic duct cells Capan-1. Pflugers Arch 2023; 475:361-379. [PMID: 36534232 PMCID: PMC9908661 DOI: 10.1007/s00424-022-02782-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Revised: 12/02/2022] [Accepted: 12/07/2022] [Indexed: 12/23/2022]
Abstract
Mechanisms of synergistic agonist stimulation and modulation of the electrochemical driving force for anion secretion are still not fully explored in human pancreatic duct epithelial cells. The first objective of this study was therefore to test whether combined agonist stimulation augments anion transport responses in the Capan-1 monolayer model of human pancreatic duct epithelium. The second objective was to test the influence of H+,K+-ATPase inhibition on anion transport in Capan-1 monolayers. The third objective was to analyze the expression and function of K+ channels in Capan-1, which could support anion secretion and cooperate with H+,K+-ATPases in pH and potassium homeostasis. The human pancreatic adenocarcinoma cell line Capan-1 was cultured conventionally or as polarized monolayers that were analyzed by Ussing chamber electrophysiological recordings. Single-cell intracellular calcium was assayed with Fura-2. mRNA isolated from Capan-1 was analyzed by use of the nCounter assay or RT-PCR. Protein expression was assessed by immunofluorescence and western blot analyses. Combined stimulation with different physiological agonists enhanced anion transport responses compared to single agonist stimulation. The responsiveness of Capan-1 cells to histamine was also revealed in these experiments. The H+,K+-ATPase inhibitor omeprazole reduced carbachol- and riluzole-induced anion transport responses. Transcript analyses revealed abundant TASK-2, TWIK-1, TWIK-2, TASK-5, KCa3.1, and KCNQ1 mRNA expression. KCNE1 mRNA and TREK-1, TREK-2, TASK-2, and KCNQ1 protein expression were also shown. This study shows that the Capan-1 model recapitulates key physiological aspects of a bicarbonate-secreting epithelium and constitutes a valuable model for functional studies on human pancreatic duct epithelium.
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13
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Kuo CS, Darmanis S, Diaz de Arce A, Liu Y, Almanzar N, Wu TTH, Quake SR, Krasnow MA. Neuroendocrinology of the lung revealed by single-cell RNA sequencing. eLife 2022; 11:e78216. [PMID: 36469459 PMCID: PMC9721618 DOI: 10.7554/elife.78216] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2022] [Accepted: 11/15/2022] [Indexed: 12/12/2022] Open
Abstract
Pulmonary neuroendocrine cells (PNECs) are sensory epithelial cells that transmit airway status to the brain via sensory neurons and locally via calcitonin gene-related peptide (CGRP) and γ- aminobutyric acid (GABA). Several other neuropeptides and neurotransmitters have been detected in various species, but the number, targets, functions, and conservation of PNEC signals are largely unknown. We used scRNAseq to profile hundreds of the rare mouse and human PNECs. This revealed over 40 PNEC neuropeptide and peptide hormone genes, most cells expressing unique combinations of 5-18 genes. Peptides are packaged in separate vesicles, their release presumably regulated by the distinct, multimodal combinations of sensors we show are expressed by each PNEC. Expression of the peptide receptors predicts an array of local cell targets, and we show the new PNEC signal angiotensin directly activates one subtype of innervating sensory neuron. Many signals lack lung targets so may have endocrine activity like those of PNEC-derived carcinoid tumors. PNECs are an extraordinarily rich and diverse signaling hub rivaling the enteroendocrine system.
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Affiliation(s)
- Christin S Kuo
- Department of Pediatrics, Stanford University School of MedicineStanfordUnited States
- Department of Biochemistry and Howard Hughes Medical Institute, Stanford UniversityStanfordUnited States
| | - Spyros Darmanis
- Department of Bioengineering, Stanford UniversityStanfordUnited States
| | - Alex Diaz de Arce
- Department of Biochemistry and Howard Hughes Medical Institute, Stanford UniversityStanfordUnited States
| | - Yin Liu
- Department of Biochemistry and Howard Hughes Medical Institute, Stanford UniversityStanfordUnited States
| | - Nicole Almanzar
- Department of Pediatrics, Stanford University School of MedicineStanfordUnited States
| | - Timothy Ting-Hsuan Wu
- Department of Biochemistry and Howard Hughes Medical Institute, Stanford UniversityStanfordUnited States
| | - Stephen R Quake
- Department of Bioengineering, Stanford UniversityStanfordUnited States
- Chan-Zuckerburg BiohubSan FranciscoUnited States
| | - Mark A Krasnow
- Department of Biochemistry and Howard Hughes Medical Institute, Stanford UniversityStanfordUnited States
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14
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Zhu Y, Schrecke S, Tang S, Odenkirk MT, Walker T, Stover L, Lyu J, Zhang T, Russell D, Baker ES, Yan X, Laganowsky A. Cupric Ions Selectively Modulate TRAAK-Phosphatidylserine Interactions. J Am Chem Soc 2022; 144:7048-7053. [PMID: 35421309 DOI: 10.1021/jacs.2c00612] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
TRAAK and TREK2 are two-pore domain K+ (K2P) channels and are modulated by diverse factors including temperature, membrane stretching, and lipids, such as phosphatidic acid. In addition, copper and zinc, both of which are essential for life, are known to regulate TREK2 and a number of other ion channels. However, the role of ions in the association of lipids with integral membrane proteins is poorly understood. Here, we discover cupric ions selectively modulate the binding of phosphatidylserine (PS) to TRAAK but not TREK2. Other divalent cations (Ca2+, Mg2+, and Zn2+) bind both channels but have no impact on binding PS and other lipids. Additionally, TRAAK binds more avidly to Cu2+ and Zn2+ than TREK2. In the presence of Cu2+, TRAAK binds similarly to PS with different acyl chains, indicating a crucial role of the serine headgroup in coordinating Cu2+. High-resolution native mass spectrometry (MS) enables the determination of equilibrium binding constants for distinct Cu2+-bound stoichiometries and uncovered the highest coupling factor corresponds to a 1:1 PS-to-Cu2+ ratio. Interestingly, the next three highest coupling factors had a ∼1.5:1 PS-to-Cu2+ ratio. Our findings bring forth the role of cupric ions as an essential cofactor in selective TRAAK-PS interactions.
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Affiliation(s)
- Yun Zhu
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
| | - Samantha Schrecke
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
| | - Shuli Tang
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
| | - Melanie T Odenkirk
- Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695, United States
| | - Thomas Walker
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
| | - Lauren Stover
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
| | - Jixing Lyu
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
| | - Tianqi Zhang
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
| | - David Russell
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
| | - Erin S Baker
- Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695, United States.,Comparative Medicine Institute, North Carolina State University, Raleigh, North Carolina 27695, United States
| | - Xin Yan
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
| | - Arthur Laganowsky
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
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15
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Miles L, Powell J, Kozak C, Song Y. Mechanosensitive Ion Channels, Axonal Growth, and Regeneration. Neuroscientist 2022:10738584221088575. [PMID: 35414308 PMCID: PMC9556659 DOI: 10.1177/10738584221088575] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Cells sense and respond to mechanical stimuli by converting those stimuli into biological signals, a process known as mechanotransduction. Mechanotransduction is essential in diverse cellular functions, including tissue development, touch sensitivity, pain, and neuronal pathfinding. In the search for key players of mechanotransduction, several families of ion channels were identified as being mechanosensitive and were demonstrated to be activated directly by mechanical forces in both the membrane bilayer and the cytoskeleton. More recently, Piezo ion channels were discovered as a bona fide mechanosensitive ion channel, and its characterization led to a cascade of research that revealed the diverse functions of Piezo proteins and, in particular, their involvement in neuronal repair.
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Affiliation(s)
- Leann Miles
- The Graduate Group in Biochemistry and Molecular Biophysics, University of Pennsylvania, Philadelphia, PA, USA
| | - Jackson Powell
- Raymond G. Perelman Center for Cellular and Molecular Therapeutics, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Casey Kozak
- Raymond G. Perelman Center for Cellular and Molecular Therapeutics, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Yuanquan Song
- The Graduate Group in Biochemistry and Molecular Biophysics, University of Pennsylvania, Philadelphia, PA, USA.,Raymond G. Perelman Center for Cellular and Molecular Therapeutics, The Children's Hospital of Philadelphia, Philadelphia, PA, USA.,Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA, USA
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16
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Pope L, Minor DL. The Polysite Pharmacology of TREK K 2P Channels. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2022; 1349:51-65. [PMID: 35138610 DOI: 10.1007/978-981-16-4254-8_4] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
K2P (KCNK) potassium channels form "background" or "leak" currents that have critical roles in cell excitability control in the brain, cardiovascular system, and somatosensory neurons. Similar to many ion channel families, studies of K2Ps have been limited by poor pharmacology. Of six K2P subfamilies, the thermo- and mechanosensitive TREK subfamily comprising K2P2.1 (TREK-1), K2P4.1 (TRAAK), and K2P10.1 (TREK-2) are the first to have structures determined for each subfamily member. These structural studies have revealed key architectural features that underlie K2P function and have uncovered sites residing at every level of the channel structure with respect to the membrane where small molecules or lipids can control channel function. This polysite pharmacology within a relatively small (~70 kDa) ion channel comprises four structurally defined modulator binding sites that occur above (Keystone inhibitor site), at the level of (K2P modulator pocket), and below (Fenestration and Modulatory lipid sites) the C-type selectivity filter gate that is at the heart of K2P function. Uncovering this rich structural landscape provides the framework for understanding and developing subtype-selective modulators to probe K2P function that may provide leads for drugs for anesthesia, pain, arrhythmia, ischemia, and migraine.
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Affiliation(s)
- Lianne Pope
- Cardiovascular Research Institute, University of California San Francisco, San Francisco, CA, US
| | - Daniel L Minor
- Cardiovascular Research Institute, University of California San Francisco, San Francisco, CA, US. .,Departments of Biochemistry and Biophysics, and Cellular and Molecular Pharmacology, University of California, San Francisco, CA, USA. .,California Institute for Quantitative Biomedical Research, University of California, San Francisco, CA, USA. .,Kavli Institute for Fundamental Neuroscience, University of California, San Francisco, CA, USA. .,Molecular Biophysics and Integrated Bio-imaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA.
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17
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Lewis KJ. Osteocyte calcium signaling - A potential translator of mechanical load to mechanobiology. Bone 2021; 153:116136. [PMID: 34339908 DOI: 10.1016/j.bone.2021.116136] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Revised: 06/25/2021] [Accepted: 07/27/2021] [Indexed: 10/20/2022]
Abstract
Osteocytes are embedded dendritic bone cells; by virtue of their position in bone tissue, ability to coordinate bone building osteoblasts and resorbing osteoclasts, and sensitivity to tissue level mechanical loading, they serve as the resident bone mechanosensor. The mechanisms osteocytes use to change mechanical loading into biological signals that drive tissue level changes has been well studied over the last 30 years, however the ways loading parameters are encoded at the cellular level are still not fully understood. Calcium signaling is a first messenger signal exhibited by osteocytes in response to mechanical forces. A body of work interrogating the mechanisms of osteocyte calcium signaling exists and is presently expanding, presenting the opportunity to better understand the relationship between calcium signaling characteristics and tuned osteocyte responses to tissue level strain features (e.g. magnitude, duration, frequency). This review covers the history of osteocyte load induced calcium signaling and highlights potential cellular mechanisms used by osteocytes to turn details about loading parameters into biological events.
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Affiliation(s)
- Karl J Lewis
- Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY, United States of America.
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18
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Two-Pore-Domain Potassium (K 2P-) Channels: Cardiac Expression Patterns and Disease-Specific Remodelling Processes. Cells 2021; 10:cells10112914. [PMID: 34831137 PMCID: PMC8616229 DOI: 10.3390/cells10112914] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 10/18/2021] [Accepted: 10/22/2021] [Indexed: 12/23/2022] Open
Abstract
Two-pore-domain potassium (K2P-) channels conduct outward K+ currents that maintain the resting membrane potential and modulate action potential repolarization. Members of the K2P channel family are widely expressed among different human cell types and organs where they were shown to regulate important physiological processes. Their functional activity is controlled by a broad variety of different stimuli, like pH level, temperature, and mechanical stress but also by the presence of lipids or pharmacological agents. In patients suffering from cardiovascular diseases, alterations in K2P-channel expression and function have been observed, suggesting functional significance and a potential therapeutic role of these ion channels. For example, upregulation of atrial specific K2P3.1 (TASK-1) currents in atrial fibrillation (AF) patients was shown to contribute to atrial action potential duration shortening, a key feature of AF-associated atrial electrical remodelling. Therefore, targeting K2P3.1 (TASK-1) channels might constitute an intriguing strategy for AF treatment. Further, mechanoactive K2P2.1 (TREK-1) currents have been implicated in the development of cardiac hypertrophy, cardiac fibrosis and heart failure. Cardiovascular expression of other K2P channels has been described, functional evidence in cardiac tissue however remains sparse. In the present review, expression, function, and regulation of cardiovascular K2P channels are summarized and compared among different species. Remodelling patterns, observed in disease models are discussed and compared to findings from clinical patients to assess the therapeutic potential of K2P channels.
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19
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Xie Y, Chen D, Jiang K, Song L, Qian N, Du Y, Yang Y, Wang F, Chen T. Hair shaft miniaturization causes stem cell depletion through mechanosensory signals mediated by a Piezo1-calcium-TNF-α axis. Cell Stem Cell 2021; 29:70-85.e6. [PMID: 34624205 DOI: 10.1016/j.stem.2021.09.009] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Revised: 07/19/2021] [Accepted: 09/13/2021] [Indexed: 12/17/2022]
Abstract
In aging, androgenic alopecia, and genetic hypotrichosis disorders, hair shaft miniaturization is often associated with hair follicle stem cell (HFSC) loss. However, the mechanism causing this stem cell depletion in vivo remains elusive. Here we show that hair shaft loss or a reduction in diameter shrinks the physical niche size, which results in mechanical compression of HFSCs and their apoptotic loss. Mechanistically, cell compression activates the mechanosensitive channel Piezo1, which triggers calcium influx. This confers tumor necrosis factor alpha (TNF-α) sensitivity in a hair-cycle-dependent manner in otherwise resistant HFSCs and induces ectopic apoptosis. Persistent hair shaft miniaturization during aging and genetic hypotrichosis disorders causes long-term HFSC loss by inducing continuous ectopic apoptosis through Piezo1. Our results identify an unconventional role of the inert hair shaft structure as a functional niche component governing HFSC survival and reveal a mechanosensory axis that regulates physical-niche-atrophy-induced stem cell depletion in vivo.
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Affiliation(s)
- Yuhua Xie
- China Agricultural University, Beijing, China; National Institute of Biological Sciences, Beijing, China
| | - Daoming Chen
- National Institute of Biological Sciences, Beijing, China
| | - Kaiju Jiang
- National Institute of Biological Sciences, Beijing, China
| | - Lifang Song
- National Institute of Biological Sciences, Beijing, China
| | - Nannan Qian
- National Institute of Biological Sciences, Beijing, China
| | - Yingxue Du
- National Institute of Biological Sciences, Beijing, China
| | - Yong Yang
- Institute of Dermatology, Chinese Academy of Medical Sciences and Peking Union Medical College, Nanjing, China
| | - Fengchao Wang
- National Institute of Biological Sciences, Beijing, China
| | - Ting Chen
- National Institute of Biological Sciences, Beijing, China; Tsinghua Institute of Multidisciplinary Biomedical Research, Tsinghua University, Beijing, China.
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20
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Rietmeijer RA, Sorum B, Li B, Brohawn SG. Physical basis for distinct basal and mechanically gated activity of the human K + channel TRAAK. Neuron 2021; 109:2902-2913.e4. [PMID: 34390650 PMCID: PMC8448962 DOI: 10.1016/j.neuron.2021.07.009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Revised: 06/10/2021] [Accepted: 07/12/2021] [Indexed: 12/24/2022]
Abstract
TRAAK is a mechanosensitive two-pore domain K+ (K2P) channel localized to nodes of Ranvier in myelinated neurons. TRAAK deletion in mice results in mechanical and thermal allodynia, and gain-of-function mutations cause the human neurodevelopmental disorder FHEIG. TRAAK displays basal and stimulus-gated activities typical of K2Ps, but the mechanistic and structural differences between these modes are unknown. Here, we demonstrate that basal and mechanically gated openings are distinguished by their conductance, kinetics, and structure. Basal openings are low conductance, short duration, and due to a conductive channel conformation with the interior cavity exposed to the surrounding membrane. Mechanically gated openings are high conductance, long duration, and due to a channel conformation in which the interior cavity is sealed to the surrounding membrane. Our results explain how dual modes of activity are produced by a single ion channel and provide a basis for the development of state-selective pharmacology with the potential to treat disease.
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Affiliation(s)
- Robert A Rietmeijer
- Department of Molecular & Cell Biology, University of California Berkeley, Berkeley, CA 94720, USA; Helen Wills Neuroscience Institute, University of California Berkeley, Berkeley, CA 94720, USA; Biophysics Graduate Program, University of California Berkeley, Berkeley, CA 94720, USA; California Institute for Quantitative Biology (QB3), University of California Berkeley, Berkeley, CA 94720, USA
| | - Ben Sorum
- Department of Molecular & Cell Biology, University of California Berkeley, Berkeley, CA 94720, USA; Helen Wills Neuroscience Institute, University of California Berkeley, Berkeley, CA 94720, USA; California Institute for Quantitative Biology (QB3), University of California Berkeley, Berkeley, CA 94720, USA
| | - Baobin Li
- Department of Molecular & Cell Biology, University of California Berkeley, Berkeley, CA 94720, USA; Helen Wills Neuroscience Institute, University of California Berkeley, Berkeley, CA 94720, USA; California Institute for Quantitative Biology (QB3), University of California Berkeley, Berkeley, CA 94720, USA
| | - Stephen G Brohawn
- Department of Molecular & Cell Biology, University of California Berkeley, Berkeley, CA 94720, USA; Helen Wills Neuroscience Institute, University of California Berkeley, Berkeley, CA 94720, USA; California Institute for Quantitative Biology (QB3), University of California Berkeley, Berkeley, CA 94720, USA.
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21
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Uchida Y, Izumizaki M. Effect of menstrual cycle and female hormones on TRP and TREK channels in modifying thermosensitivity and physiological functions in women. J Therm Biol 2021; 100:103029. [PMID: 34503776 DOI: 10.1016/j.jtherbio.2021.103029] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Revised: 05/10/2021] [Accepted: 05/11/2021] [Indexed: 12/15/2022]
Abstract
Thermoregulation is crucial for human survival at various ambient temperatures. Transient receptor potential (TRP) and TWIK-related K+ (TREK) channels expressed in sensory neurons play a role in peripheral thermosensitivity for temperature detection. In addition, these channels have various physiological roles in the skeletal, nervous, immune, vascular, digestive, and urinary systems. In women, the female hormones estradiol (E2) and progesterone (P4), which fluctuate during the menstrual cycle, affect various physiological functions, such as thermoregulation in hot and cold environments. The present review describes the effect of female hormones on TRP and TREK channels and related physiological functions. The P4 decreased thermosensitivity via TRPV1. E2 facilitates temporomandibular joint disease (TRPV1), breast cancer (TRPM8), and calcium absorption in the digestive system (TRPV5 and TRPV6), inhibits the facilitation of vasoconstriction (TRPM3), nerve inflammation (TRPM4), sweetness sensitivity (TRPM5), and menstrual disorders (TRPC1), and prevents insulin resistance (TRPC5) via each channel. P4 inhibits vasoconstriction (TRPM3), sweetness sensitivity (TRPM5), ciliary motility in the lungs (TRPV4), menstrual disorder (TRPC1), and immunity (TRPC3), and facilitates breast cancer (TRPV6) via each channel as indicated. The effects of female hormones on TREK channels and physiological functions are still under investigation. In summary, female hormones influence physiological functions via some TRP channels; however, the literature is not comprehensive and future studies are needed, especially those related to thermoregulation in women.
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Affiliation(s)
- Yuki Uchida
- Department of Physiology, Showa University School of Medicine, Tokyo, Japan.
| | - Masahiko Izumizaki
- Department of Physiology, Showa University School of Medicine, Tokyo, Japan
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22
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Muscimol Directly Activates the TREK-2 Channel Expressed in GABAergic Neurons through Its N-Terminus. Int J Mol Sci 2021; 22:ijms22179320. [PMID: 34502229 PMCID: PMC8431218 DOI: 10.3390/ijms22179320] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Revised: 08/25/2021] [Accepted: 08/25/2021] [Indexed: 11/23/2022] Open
Abstract
The two-pore domain K+ (K2P) channel, which is involved in setting the resting membrane potential in neurons, is an essential target for receptor agonists. Activation of the γ-aminobutyric acid (GABA) receptors (GABAAR and GABABR) reduces cellular excitability through Cl- influx and K+ efflux in neurons. Relatively little is known about the link between GABAAR and the K+ channel. The present study was performed to identify the effect of GABAR agonists on K2P channel expression and activity in the neuroblastic B35 cells that maintain glutamic acid decarboxylase (GAD) activity and express GABA. TASK and TREK/TRAAK mRNA were expressed in B35 cells with a high level of TREK-2 and TRAAK. In addition, TREK/TRAAK proteins were detected in the GABAergic neurons obtained from GABA transgenic mice. Furthermore, TREK-2 mRNA and protein expression levels were markedly upregulated in B35 cells by GABAAR and GABABR agonists. In particular, muscimol, a GABAAR agonist, significantly increased TREK-2 expression and activity, but the effect was reduced in the presence of the GABAAR antagonist bicuculine or TREK-2 inhibitor norfluoxetine. In the whole-cell and single-channel patch configurations, muscimol increased TREK-2 activity, but the muscimol effect disappeared in the N-terminal deletion mutant. These results indicate that muscimol directly induces TREK-2 activation through the N-terminus and suggest that muscimol can reduce cellular excitability by activating the TREK-2 channel and by inducing Cl- influx in GABAergic neurons.
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23
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Lengyel M, Enyedi P, Czirják G. Negative Influence by the Force: Mechanically Induced Hyperpolarization via K 2P Background Potassium Channels. Int J Mol Sci 2021; 22:ijms22169062. [PMID: 34445768 PMCID: PMC8396510 DOI: 10.3390/ijms22169062] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Revised: 08/19/2021] [Accepted: 08/20/2021] [Indexed: 02/08/2023] Open
Abstract
The two-pore domain K2P subunits form background (leak) potassium channels, which are characterized by constitutive, although not necessarily constant activity, at all membrane potential values. Among the fifteen pore-forming K2P subunits encoded by the KCNK genes, the three members of the TREK subfamily, TREK-1, TREK-2, and TRAAK are mechanosensitive ion channels. Mechanically induced opening of these channels generally results in outward K+ current under physiological conditions, with consequent hyperpolarization and inhibition of membrane potential-dependent cellular functions. In the past decade, great advances have been made in the investigation of the molecular determinants of mechanosensation, and members of the TREK subfamily have emerged among the best-understood examples of mammalian ion channels directly influenced by the tension of the phospholipid bilayer. In parallel, the crucial contribution of mechano-gated TREK channels to the regulation of membrane potential in several cell types has been reported. In this review, we summarize the general principles underlying the mechanical activation of K2P channels, and focus on the physiological roles of mechanically induced hyperpolarization.
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24
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Herrera-Pérez S, Campos-Ríos A, Rueda-Ruzafa L, Lamas JA. Contribution of K2P Potassium Channels to Cardiac Physiology and Pathophysiology. Int J Mol Sci 2021; 22:ijms22126635. [PMID: 34205717 PMCID: PMC8234311 DOI: 10.3390/ijms22126635] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Revised: 06/08/2021] [Accepted: 06/18/2021] [Indexed: 12/28/2022] Open
Abstract
Years before the first two-pore domain potassium channel (K2P) was cloned, certain ion channels had already been demonstrated to be present in the heart with characteristics and properties usually attributed to the TREK channels (a subfamily of K2P channels). K2P channels were later detected in cardiac tissue by RT-PCR, although the distribution of the different K2P subfamilies in the heart seems to depend on the species analyzed. In order to collect relevant information in this regard, we focus here on the TWIK, TASK and TREK cardiac channels, their putative roles in cardiac physiology and their implication in coronary pathologies. Most of the RNA expression data and electrophysiological recordings available to date support the presence of these different K2P subfamilies in distinct cardiac cells. Likewise, we show how these channels may be involved in certain pathologies, such as atrial fibrillation, long QT syndrome and Brugada syndrome.
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25
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Huang L, Xu G, Jiang R, Luo Y, Zuo Y, Liu J. Development of Non-opioid Analgesics Targeting Two-pore Domain Potassium Channels. Curr Neuropharmacol 2021; 20:16-26. [PMID: 33827408 PMCID: PMC9199554 DOI: 10.2174/1570159x19666210407152528] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Revised: 03/14/2021] [Accepted: 03/24/2021] [Indexed: 02/08/2023] Open
Abstract
Two-pore domain potassium (K2P) channels are a diverse family of potassium channels. K2P channels generate background leak potassium currents to regulate cellular excitability and are thereby involved in a wide range of neurological disorders. K2P channels are modulated by a variety of physicochemical factors such as mechanical stretch, temperature, and pH. In the the peripheral nervous system (PNS), K2P channels are widely expressed in nociceptive neurons and play a critical roles in pain perception. In this review, we summarize the recent advances in the pharmacological properties of K2P channels, with a focus on the exogenous small-molecule activators targeting K2P channels. We emphasize the subtype-selectivity, cellular and in vivo pharmacological properties of all the reported small-molecule activators. The key underlying analgesic mechanisms mediated by K2P are also summarized based on the data in the literature from studies using small-molecule activators and genetic knock-out animals. We discuss advantages and limitations of the translational perspectives of K2P in pain medicine and provide outstanding questions for future studies in the end.
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Affiliation(s)
- Lu Huang
- Laboratory of Anesthesia and Critical Care Medicine, National-Local Joint Engineering Research Center of Translational Medicine of Anesthesiology, West China Hospital, Sichuan University, Chengdu 610000, Sichuan. China
| | - Guangyin Xu
- Department of Physiology and Neurobiology, Institute of Neuroscience, Medical College of Soochow University, Suzhou, 215123, Jiangsu. China
| | - Ruotian Jiang
- Laboratory of Anesthesia and Critical Care Medicine, National-Local Joint Engineering Research Center of Translational Medicine of Anesthesiology, West China Hospital, Sichuan University, Chengdu 610000, Sichuan. China
| | - Yuncheng Luo
- Laboratory of Anesthesia and Critical Care Medicine, National-Local Joint Engineering Research Center of Translational Medicine of Anesthesiology, West China Hospital, Sichuan University, Chengdu 610000, Sichuan. China
| | - Yunxia Zuo
- Laboratory of Anesthesia and Critical Care Medicine, National-Local Joint Engineering Research Center of Translational Medicine of Anesthesiology, West China Hospital, Sichuan University, Chengdu 610000, Sichuan. China
| | - Jin Liu
- Laboratory of Anesthesia and Critical Care Medicine, National-Local Joint Engineering Research Center of Translational Medicine of Anesthesiology, West China Hospital, Sichuan University, Chengdu 610000, Sichuan. China
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26
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Lee H, Lolicato M, Arrigoni C, Minor DL. Production of K 2P2.1 (TREK-1) for structural studies. Methods Enzymol 2021; 653:151-188. [PMID: 34099170 DOI: 10.1016/bs.mie.2021.02.013] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
K2P (KCNK) potassium channels form 'background' or 'leak' currents that are important for controlling cell excitability in the brain, cardiovascular system, and somatosensory neurons. K2P2.1 (TREK-1) is one of the founding members of this family and one of the first well-characterized polymodal ion channels capable of responding to a variety of physical and chemical gating cues. Of the six K2P subfamilies, the thermo-and mechano-sensitive TREK subfamily comprising K2P2.1 (TREK-1), K2P4.1 (TRAAK), and K2P10.1 (TREK-2) is the first to have structures determined for each subfamily member. These structural studies have revealed key architectural features that provide a framework for understanding how gating cues sensed by different channel elements converge on the K2P selectivity filter C-type gate. TREK family structural studies have also revealed numerous sites where small molecules or lipids bind and affect channel function. This rich structural landscape provides the framework for probing K2P function and for the development of new K2P-directed agents. Such molecules may be useful for affecting processes where TREK channels are important such as anesthesia, pain, arrythmia, ischemia, migraine, intraocular pressure, and lung injury. Production of high quality protein samples is key to addressing new questions about K2P function and pharmacology. Here, we present methods for producing pure K2P2.1 (TREK-1) suitable for advancing towards these goals through structural and biochemical studies.
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Affiliation(s)
- Haerim Lee
- Cardiovascular Research Institute, University of California, San Francisco, CA, United States
| | - Marco Lolicato
- Cardiovascular Research Institute, University of California, San Francisco, CA, United States
| | - Cristina Arrigoni
- Cardiovascular Research Institute, University of California, San Francisco, CA, United States
| | - Daniel L Minor
- Cardiovascular Research Institute, University of California, San Francisco, CA, United States; Departments of Biochemistry and Biophysics, and Cellular and Molecular Pharmacology, University of California, San Francisco, CA, United States; California Institute for Quantitative Biomedical Research, University of California, San Francisco, CA, United States; Kavli Institute for Fundamental Neuroscience, University of California, San Francisco, CA, United States; Molecular Biophysics and Integrated Bio-imaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, United States.
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27
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Momin A, Bahrampour S, Min HK, Chen X, Wang X, Sun Y, Huang X. Channeling Force in the Brain: Mechanosensitive Ion Channels Choreograph Mechanics and Malignancies. Trends Pharmacol Sci 2021; 42:367-384. [PMID: 33752907 DOI: 10.1016/j.tips.2021.02.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Revised: 02/15/2021] [Accepted: 02/26/2021] [Indexed: 12/15/2022]
Abstract
Force is everywhere. Through cell-intrinsic activities and interactions with the microenvironment, cells generate, transmit, and sense mechanical forces, such as compression, tension, and shear stress. These forces shape the mechanical properties of cells and tissues. Akin to how balanced biochemical signaling safeguards physiological processes, a mechanical optimum is required for homeostasis. The brain constructs a mechanical optimum from its cellular and extracellular constituents. However, in brain cancer, the mechanical properties are disrupted: tumor and nontumoral cells experience dysregulated solid and fluid stress, while tumor tissue develops altered stiffness. Mechanosensitive (MS) ion channels perceive mechanical cues to govern ion flux and cellular signaling. In this review, we describe the mechanical properties of the brain in healthy and cancer states and illustrate MS ion channels as sensors of mechanical cues to regulate malignant growth. Targeting MS ion channels offers disease insights at the interface of cancer, neuroscience, and mechanobiology to reveal therapeutic opportunities in brain tumors.
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Affiliation(s)
- Ali Momin
- Program in Developmental and Stem Cell Biology, The Hospital for Sick Children, Toronto, ONT, M5G 1X8, Canada; Arthur and Sonia Labatt Brain Tumour Research Centre, The Hospital for Sick Children, Toronto, ONT, M5G 1X8, Canada; Department of Molecular Genetics, University of Toronto, Toronto, ONT, M5S 3E1, Canada.
| | - Shahrzad Bahrampour
- Program in Developmental and Stem Cell Biology, The Hospital for Sick Children, Toronto, ONT, M5G 1X8, Canada; Arthur and Sonia Labatt Brain Tumour Research Centre, The Hospital for Sick Children, Toronto, ONT, M5G 1X8, Canada; Department of Cell and Molecular Biology (CMB), Karolinska Institutet, Stockholm, 171 77, Sweden
| | - Hyun-Kee Min
- Program in Developmental and Stem Cell Biology, The Hospital for Sick Children, Toronto, ONT, M5G 1X8, Canada; Arthur and Sonia Labatt Brain Tumour Research Centre, The Hospital for Sick Children, Toronto, ONT, M5G 1X8, Canada; Department of Molecular Genetics, University of Toronto, Toronto, ONT, M5S 3E1, Canada
| | - Xin Chen
- Program in Developmental and Stem Cell Biology, The Hospital for Sick Children, Toronto, ONT, M5G 1X8, Canada; Arthur and Sonia Labatt Brain Tumour Research Centre, The Hospital for Sick Children, Toronto, ONT, M5G 1X8, Canada
| | - Xian Wang
- Program in Developmental and Stem Cell Biology, The Hospital for Sick Children, Toronto, ONT, M5G 1X8, Canada; Arthur and Sonia Labatt Brain Tumour Research Centre, The Hospital for Sick Children, Toronto, ONT, M5G 1X8, Canada
| | - Yu Sun
- Department of Mechanical and Industrial Engineering, University of Toronto, Toronto, ONT, M5S 3G8, Canada
| | - Xi Huang
- Program in Developmental and Stem Cell Biology, The Hospital for Sick Children, Toronto, ONT, M5G 1X8, Canada; Arthur and Sonia Labatt Brain Tumour Research Centre, The Hospital for Sick Children, Toronto, ONT, M5G 1X8, Canada; Department of Molecular Genetics, University of Toronto, Toronto, ONT, M5S 3E1, Canada.
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28
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Choi SW, Woo J, Park KS, Ko J, Jeon YK, Choi SW, Yoo HY, Kho I, Kim TJ, Kim SJ. Higher expression of KCNK10 (TREK-2) K + channels and their functional upregulation by lipopolysaccharide treatment in mouse peritoneal B1a cells. Pflugers Arch 2021; 473:659-671. [PMID: 33586023 DOI: 10.1007/s00424-021-02526-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Revised: 01/10/2021] [Accepted: 01/28/2021] [Indexed: 11/24/2022]
Abstract
Innate-like CD5+ B1a cells localized in serous cavities are activated by innate stimuli, such as lipopolysaccharide (LPS), leading to T cell-independent antibody responses. Although ion channels play crucial roles in the homeostasis and activation of immune cells, the electrophysiological properties of B1a cells have not been investigated to date. Previously, in the mouse B cell lymphoma cells, we found that the voltage-independent two-pore-domain potassium (K2P) channels generate a negative membrane potential and drive Ca2+ influx. Here, we newly compared the expression and activities of K2P channels in mouse splenic follicular B (FoB), marginal zone B (MZB), and peritoneal B1a cells. Next-generation sequencing analysis showed higher levels of transcripts for TREK-2 and TWIK-2 in B1a cells than those in FoB or MZB cells. Electrophysiological analysis, using patch clamp technique, revealed higher activity of TREK-2 with the characteristic large unitary conductance (~ 250 pS) in B1a than that in FoB or MZB cells. TREK-2 activity was further increased by LPS treatment (>2 h), which was more prominent in B1a than that in MZB or FoB cells. The cytosolic Ca2+ concentration of B cells was decreased by high-K+-induced depolarization (ΔRKCl (%)), suggesting the basal Ca2+ influx to be driven by negative membrane potential. The LPS treatment significantly increased the ΔRKCl (%) in B1a, though not in FoB and MZB cells. Our study was the first to compare the K2P channels in mouse primary B cell subsets, elucidating the functional upregulation of TREK-2 and augmentation of Ca2+ influx by the stimulation of Toll-like receptor 4 in B1a cells.
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Affiliation(s)
- Si Won Choi
- Department of Physiology, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Joohan Woo
- Department of Physiology and Ion Channel Disease Research Center, Dongguk University College of Medicine, Seoul, Republic of Korea
| | - Kyung Sun Park
- Wide River Institute of Immunology, Seoul National University College of Medicine, Hongcheon, Republic of Korea
| | - Juyeon Ko
- Department of Physiology, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Young Keul Jeon
- Department of Physiology, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Seong Woo Choi
- Department of Physiology, Seoul National University College of Medicine, Seoul, Republic of Korea.,Department of Physiology and Ion Channel Disease Research Center, Dongguk University College of Medicine, Seoul, Republic of Korea.,Ischemic/Hypoxic Disease Institute, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Hae Young Yoo
- Department of Nursing, Chung-Ang University, Seoul, Republic of Korea
| | - Inseong Kho
- Department of Immunology, Sungkyunkwan University School of Medicine, Suwon, Republic of Korea
| | - Tae Jin Kim
- Department of Immunology, Sungkyunkwan University School of Medicine, Suwon, Republic of Korea
| | - Sung Joon Kim
- Department of Physiology, Seoul National University College of Medicine, Seoul, Republic of Korea. .,Wide River Institute of Immunology, Seoul National University College of Medicine, Hongcheon, Republic of Korea. .,Ischemic/Hypoxic Disease Institute, Seoul National University College of Medicine, Seoul, Republic of Korea.
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29
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Abstract
Mechanosensing is a key feature through which organisms can receive inputs from the environment and convert them into specific functional and behavioral outputs. Mechanosensation occurs in many cells and tissues, regulating a plethora of molecular processes based on the distribution of forces and stresses both at the cell membrane and at the intracellular organelles levels, through complex interactions between cells’ microstructures, cytoskeleton, and extracellular matrix. Although several primary and secondary mechanisms have been shown to contribute to mechanosensation, a fundamental pathway in simple organisms and mammals involves the presence of specialized sensory neurons and the presence of different types of mechanosensitive ion channels on the neuronal cell membrane. In this contribution, we present a review of the main ion channels which have been proven to be significantly involved in mechanotransduction in neurons. Further, we discuss recent studies focused on the biological mechanisms and modeling of mechanosensitive ion channels’ gating, and on mechanotransduction modeling at different scales and levels of details.
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30
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Abstract
Two-pore domain potassium channels are formed by subunits that each contain two pore-loops moieties. Whether the channels are expressed in yeast or the human central nervous system, two subunits come together to form a single potassium selective pore. TOK1, the first two-domain channel was cloned from Saccharomyces cerevisiae in 1995 and soon thereafter, 15 distinct K2P subunits were identified in the human genome. The human K2P channels are stratified into six K2P subfamilies based on sequence as well as physiological or pharmacological similarities. Functional K2P channels pass background (or "leak") K+ currents that shape the membrane potential and excitability of cells in a broad range of tissues. In the years since they were first described, classical functional assays, latterly coupled with state-of-the-art structural and computational studies have revealed the mechanistic basis of K2P channel gating in response to specific physicochemical or pharmacological stimuli. The growing appreciation that K2P channels can play a pivotal role in the pathophysiology of a growing spectrum of diseases makes a compelling case for K2P channels as targets for drug discovery. Here, we summarize recent advances in unraveling the structure, function, and pharmacology of the K2P channels.
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Affiliation(s)
- Jordie M Kamuene
- Department of Pharmaceutical Sciences, Northeastern University, Boston, MA, USA
| | - Yu Xu
- Department of Pharmaceutical Sciences, Northeastern University, Boston, MA, USA
| | - Leigh D Plant
- Department of Pharmaceutical Sciences, Northeastern University, Boston, MA, USA.
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31
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Jin P, Jan LY, Jan YN. Mechanosensitive Ion Channels: Structural Features Relevant to Mechanotransduction Mechanisms. Annu Rev Neurosci 2020; 43:207-229. [PMID: 32084327 DOI: 10.1146/annurev-neuro-070918-050509] [Citation(s) in RCA: 123] [Impact Index Per Article: 30.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Activation of mechanosensitive ion channels underlies a variety of fundamental physiological processes that require sensation of mechanical force. Different mechanosensitive channels adapt distinctive structures and mechanotransduction mechanisms to fit their biological roles. How mechanosensitive channels work, especially in animals, has been extensively studied in the past decade. Here we review key findings in the functional and structural characterizations of these channels and highlight the structural features relevant to the mechanotransduction mechanism of each specific channel.
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Affiliation(s)
- Peng Jin
- Department of Physiology, University of California, San Francisco, California 94158, USA;
| | - Lily Yeh Jan
- Department of Physiology, University of California, San Francisco, California 94158, USA; .,Department of Biochemistry and Biophysics and Howard Hughes Medical Institute, University of California, San Francisco, California 94158, USA
| | - Yuh-Nung Jan
- Department of Physiology, University of California, San Francisco, California 94158, USA; .,Department of Biochemistry and Biophysics and Howard Hughes Medical Institute, University of California, San Francisco, California 94158, USA
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32
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Paschou M, Maier L, Papazafiri P, Selescu T, Dedos SG, Babes A, Doxakis E. Neuronal microRNAs modulate TREK two-pore domain K + channel expression and current density. RNA Biol 2020; 17:651-662. [PMID: 31994436 DOI: 10.1080/15476286.2020.1722450] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
The TREK family of leak potassium channels has been found to play critical roles in nociception, sensitivity to general anaesthetics, neuroprotection, and memory. The three members of the family, TREK1, TREK2 and TRAAK establish the resting potential and modify the duration, frequency and amplitude of action potentials. Despite their apparent importance, the repertoire of regulatory interactions utilized by cells to control their expression is poorly understood. Herein, the contribution of miRNAs in the regulation of their post-transcriptional gene expression has been examined. Using different assays, miR-124 and to a lesser extent miR-128 and miR-183 were found to reduce TREK1 and TREK2 levels through specific binding to their 3'UTRs. In contrast, miR-9 which was predicted to bind to TRAAK 3'UTR, did not alter its expression. Expression of miR-124, miR-128 and miR-183 was found to mirror that of Trek1 and Trek2 mRNAs during brain development. Moreover, application of proinflammatory mediators in dorsal root ganglion (DRG) neurons revealed an inverse correlation between miR-124 and Trek1 and Trek2 mRNA expression. Voltage clamp recordings of TREK2-mediated currents showed that miR-124 reduced the sensitivity of TREK2-expressing cells to non-aversive warmth stimulation. Overall, these findings reveal a significant regulatory mechanism by which TREK1 and TREK2 expression and hence activity are controlled in neurons and uncover new druggable targets for analgesia and neuroprotection.Abbreviations: microRNA: miRNA; UTR: untranslated region; K2p channels: two-pore domain K+channels; DRG: dorsal root ganglion; CNS: central nervous system; FBS: fetal bovine serum; TuD: Tough Decoy; TREK: tandem P-domain weak inward rectifying K+ (TWIK)-related K+ channel 1; TRAAK: TWIK-related arachidonic acid K+.
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Affiliation(s)
- Maria Paschou
- Center for Basic Research, Biomedical Research Foundation, Academy of Athens, Athens, Greece.,Department of Biology, National and Kapodistrian University of Athens, Athens, Greece
| | - Larisa Maier
- Department of Anatomy, Physiology and Biophysics, Faculty of Biology, University of Bucharest, Bucharest, Romania
| | - Panagiota Papazafiri
- Department of Biology, National and Kapodistrian University of Athens, Athens, Greece
| | - Tudor Selescu
- Department of Anatomy, Physiology and Biophysics, Faculty of Biology, University of Bucharest, Bucharest, Romania
| | - Skarlatos G Dedos
- Department of Biology, National and Kapodistrian University of Athens, Athens, Greece
| | - Alexandru Babes
- Department of Anatomy, Physiology and Biophysics, Faculty of Biology, University of Bucharest, Bucharest, Romania
| | - Epaminondas Doxakis
- Center for Basic Research, Biomedical Research Foundation, Academy of Athens, Athens, Greece
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33
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Reyes-Pardo H, Sánchez-Herrera DP. Mechanosensitive ion channel inhibitors promote the stiffening of the plasma membrane of mouse sensory neurons. SOFT MATTER 2019; 15:8320-8328. [PMID: 31565715 DOI: 10.1039/c9sm01230c] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The mechanosensitivity of cells depends on the lipid-protein interactions of the plasma membrane. Affectations in the lipid region of the plasma membrane affect the transduction of mechanical forces, and any molecule that modifies the biophysical integrity of the lipid bilayer can alter the mechanical activity of the proteins inside the membrane. To understand whether inhibitors of mechanically activated ion channels affect the mechanical properties of the plasma membrane, we evaluated the rigidity of the membrane of sensory neurons of the DRG of mice using a variant of the scanning ion conductance microscopy method, which allows us to calculate the Young's modulus of individual cells before and after the perfusion of different doses of Gd3+, ruthenium red and GsMTx-4. Our results suggest that these molecules compromise the membrane by increasing the Young's modulus value, which indicates that the membrane becomes more rigid; these compounds act through different mechanisms and by a non-specific manner, each one shows a certain preference for specific cell subpopulations, depending on their cell size and their reactivity to isolectin B4. Our results support the idea that the biophysical properties that result from the interactions that arise in the membranes are part of the mechanotransduction process.
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Affiliation(s)
- Humberto Reyes-Pardo
- Unidad Monterrey, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Apodaca, Nuevo León, Mexico.
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34
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Moehring F, Halder P, Seal RP, Stucky CL. Uncovering the Cells and Circuits of Touch in Normal and Pathological Settings. Neuron 2019; 100:349-360. [PMID: 30359601 DOI: 10.1016/j.neuron.2018.10.019] [Citation(s) in RCA: 97] [Impact Index Per Article: 19.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2018] [Revised: 10/08/2018] [Accepted: 10/09/2018] [Indexed: 01/18/2023]
Abstract
The sense of touch is fundamental as it provides vital, moment-to-moment information about the nature of our physical environment. Primary sensory neurons provide the basis for this sensation in the periphery; however, recent work demonstrates that touch transduction mechanisms also occur upstream of the sensory neurons via non-neuronal cells such as Merkel cells and keratinocytes. Within the spinal cord, deep dorsal horn circuits transmit innocuous touch centrally and also transform touch into pain in the setting of injury. Here non-neuronal cells play a key role in the induction and maintenance of persistent mechanical pain. This review highlights recent advances in our understanding of mechanosensation, including a growing appreciation for the role of non-neuronal cells in both touch and pain.
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Affiliation(s)
- Francie Moehring
- Department of Cell Biology, Neurobiology, and Anatomy, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Priyabrata Halder
- Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA; Center for the Neural Basis of Cognition, Pittsburgh, PA 15213, USA
| | - Rebecca P Seal
- Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA; Center for the Neural Basis of Cognition, Pittsburgh, PA 15213, USA; Pittsburgh Center for Pain Research, Pittsburgh, PA 15213, USA
| | - Cheryl L Stucky
- Department of Cell Biology, Neurobiology, and Anatomy, Medical College of Wisconsin, Milwaukee, WI 53226, USA.
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35
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Bedoya M, Rinné S, Kiper AK, Decher N, González W, Ramírez D. TASK Channels Pharmacology: New Challenges in Drug Design. J Med Chem 2019; 62:10044-10058. [PMID: 31260312 DOI: 10.1021/acs.jmedchem.9b00248] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Rational drug design targeting ion channels is an exciting and always evolving research field. New medicinal chemistry strategies are being implemented to explore the wild chemical space and unravel the molecular basis of the ion channels modulators binding mechanisms. TASK channels belong to the two-pore domain potassium channel family and are modulated by extracellular acidosis. They are extensively distributed along the cardiovascular and central nervous systems, and their expression is up- and downregulated in different cancer types, which makes them an attractive therapeutic target. However, TASK channels remain unexplored, and drugs designed to target these channels are poorly selective. Here, we review TASK channels properties and their known blockers and activators, considering the new challenges in ion channels drug design and focusing on the implementation of computational methodologies in the drug discovery process.
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Affiliation(s)
- Mauricio Bedoya
- Centro de Bioinformática y Simulación Molecular (CBSM) , Universidad de Talca , 1 Poniente No. 1141 , 3460000 Talca , Chile
| | - Susanne Rinné
- Institute for Physiology and Pathophysiology, Vegetative Physiology and Marburg Center for Mind, Brain and Behavior, MCMBB , Philipps-University of Marburg , Deutschhausstraße 2 , Marburg 35037 , Germany
| | - Aytug K Kiper
- Institute for Physiology and Pathophysiology, Vegetative Physiology and Marburg Center for Mind, Brain and Behavior, MCMBB , Philipps-University of Marburg , Deutschhausstraße 2 , Marburg 35037 , Germany
| | - Niels Decher
- Institute for Physiology and Pathophysiology, Vegetative Physiology and Marburg Center for Mind, Brain and Behavior, MCMBB , Philipps-University of Marburg , Deutschhausstraße 2 , Marburg 35037 , Germany
| | - Wendy González
- Centro de Bioinformática y Simulación Molecular (CBSM) , Universidad de Talca , 1 Poniente No. 1141 , 3460000 Talca , Chile.,Millennium Nucleus of Ion Channels-Associated Diseases (MiNICAD) , Universidad de Talca , 1 Poniente No. 1141 , 3460000 Talca , Chile
| | - David Ramírez
- Instituto de Ciencias Biomédicas, Facultad de Ciencias de la Salud , Universidad Autónoma de Chile , El Llano Subercaseaux 2801, Piso 6 , 8900000 Santiago , Chile
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36
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Şterbuleac D. Molecular determinants of chemical modulation of two-pore domain potassium channels. Chem Biol Drug Des 2019; 94:1596-1614. [PMID: 31124599 DOI: 10.1111/cbdd.13571] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Revised: 04/29/2019] [Accepted: 05/05/2019] [Indexed: 12/16/2022]
Abstract
The K+ ion channels comprising the two-pore domain (K2P) family have specific biophysical roles in generating the critical regulatory K+ current. Ion flow through K2P channels and, implicitly, channel regulation is mediated by diverse metabolic and physical inputs such as mechanical stimulation, interaction with lipids or endogenous regulators, intra- or extracellular pH, and phosphorylation, while their function can be finely tuned by chemical compounds. In the latter category, some drug-channel interactions can lead to side effects or have clinical action, while identifying novel chemical modulators of K2Ps is an area of intense research. Due to their cellular and therapeutic importance, much attention was turned to these channels in recent years and several experimental approaches have pinpointed the molecular determinants of K2P chemical modulation. Given their unique structural features and properties, chemical modulators act on K2P channels in multiple and diverse ways. In this review, the particularities of K2P modulation by chemical compounds, such as binding modality, affinity, or position, are identified, synthesized, and linked to structural and functional properties in order to refer to how activators and blockers modify channel function and vice versa, focusing on specificity related to protein structure (and its modification) and cross-linking information among different subfamilies.
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Affiliation(s)
- Daniel Şterbuleac
- Doctoral School of Biology, Faculty of Biology, "Alexandru Ioan Cuza" University of Iasi, Iasi, Romania
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37
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Rodrigues R, Danskog K, Överby AK, Arnberg N. Characterizing the cellular attachment receptor for Langat virus. PLoS One 2019; 14:e0217359. [PMID: 31163044 PMCID: PMC6548386 DOI: 10.1371/journal.pone.0217359] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2019] [Accepted: 04/23/2019] [Indexed: 12/31/2022] Open
Abstract
Tick-borne encephalitis infections have increased the last 30 years. The mortality associated to this viral infection is 0.5 to 30% with a risk of permanent neurological sequelae, however, no therapeutic is currently available. The first steps of virus-cell interaction, such as attachment and entry, are of importance to understand pathogenesis and tropism. Several molecules have been shown to interact with tick-borne encephalitis virus (TBEV) at the plasma membrane surface, yet, no studies have proven that these are specific entry receptors. In this study, we set out to characterize the cellular attachment receptor(s) for TBEV using the naturally attenuated member of the TBEV complex, Langat virus (LGTV), as a model. Inhibiting or cleaving different molecules from the surface of A549 cells, combined with inhibition assays using peptide extracts from high LGTV binding cells, revealed that LGTV attachment to host cells is dependent on plasma membrane proteins, but not on glycans or glycolipids, and suggested that LGTV might use different cellular attachment factors on different cell types. Based on this, we developed a transcriptomic approach to generate a list of candidate attachment and entry receptors. Our findings shed light on the first step of the flavivirus life-cycle and provide candidate receptors that might serve as a starting point for future functional studies to identify the specific attachment and/or entry receptor for LGTV and TBEV.
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Affiliation(s)
- Raquel Rodrigues
- Virology, Department of Clinical Microbiology, Umeå University, Umeå, Sweden
| | - Katarina Danskog
- Virology, Department of Clinical Microbiology, Umeå University, Umeå, Sweden
| | - Anna K. Överby
- Virology, Department of Clinical Microbiology, Umeå University, Umeå, Sweden
| | - Niklas Arnberg
- Virology, Department of Clinical Microbiology, Umeå University, Umeå, Sweden
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Pineda RH, Hypolite J, Lee S, Carrasco A, Iguchi N, Meacham RB, Malykhina AP. Altered detrusor contractility and voiding patterns in mice lacking the mechanosensitive TREK-1 channel. BMC Urol 2019; 19:40. [PMID: 31113422 PMCID: PMC6528348 DOI: 10.1186/s12894-019-0475-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2018] [Accepted: 05/13/2019] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Previously published results from our laboratory identified a mechano-gated two-pore domain potassium channel, TREK-1, as a main mechanosensor in the smooth muscle of the human urinary bladder. One of the limitations of in vitro experiments on isolated human detrusor included inability to evaluate in vivo effects of TREK-1 on voiding function, as the channel is also expressed in the nervous system, and may modulate micturition via neural pathways. Therefore, in the present study, we aimed to assess the role of TREK-1 channel in bladder function and voiding patterns in vivo by using TREK-1 knockout (KO) mice. METHODS Adult C57BL/6 J wild-type (WT, N = 32) and TREK-1 KO (N = 33) mice were used in this study. The overall phenotype and bladder function were evaluated by gene and protein expression of TREK-1 channel, in vitro contractile experiments using detrusor strips in response to stretch and pharmacological stimuli, and cystometry in unanesthetized animals. RESULTS TREK-1 KO animals had an elevated basal muscle tone and enhanced spontaneous activity in the detrusor without detectable changes in bladder morphology/histology. Stretch applied to isolated detrusor strips increased the amplitude of spontaneous contractions by 109% in the TREK-1 KO group in contrast to a 61% increase in WT mice (p ≤ 0.05 to respective baseline for each group). The detrusor strips from TREK-1 KO mice also generated more contractile force in response to electric field stimulation and high potassium concentration in comparison to WT group (p ≤ 0.05 for both tests). However, cystometric recordings from TREK-1 KO mice revealed a significant increase in the duration of the intermicturition interval, enhanced bladder capacity and increased number of non-voiding contractions in comparison to WT mice. CONCLUSIONS Our results provide evidence that global down-regulation of TREK-1 channels has dual effects on detrusor contractility and micturition patterns in vivo. The observed differences are likely due to expression of TREK-1 channel not only in detrusor myocytes but also in afferent and efferent neural pathways involved in regulation of micturition which may underly the "mixed" voiding phenotype in TREK-1 KO mice.
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Affiliation(s)
- Ricardo H Pineda
- Division of Urology, Department of Surgery, University of Colorado Denver,Anschutz Medical Campus, 12700 E 19th Ave, M/S C317, Aurora, CO, 80045, USA
| | - Joseph Hypolite
- Division of Urology, Department of Surgery, University of Colorado Denver,Anschutz Medical Campus, 12700 E 19th Ave, M/S C317, Aurora, CO, 80045, USA
| | - Sanghee Lee
- Department of Urology, University of California San Diego, 3855 Health Science Drive, Room 4345, Bay 4LL, La Jolla, CA, 92093, USA
| | - Alonso Carrasco
- Children's Mercy Hospital, 2401 Gillham Rd, Kansas City, MO, 64108, USA
| | - Nao Iguchi
- Division of Urology, Department of Surgery, University of Colorado Denver,Anschutz Medical Campus, 12700 E 19th Ave, M/S C317, Aurora, CO, 80045, USA
| | - Randall B Meacham
- Division of Urology, Department of Surgery, University of Colorado Denver, Academic Office One Bldg., Rm 5602, 12631 East 17th Ave., M/S C319, Aurora, CO, 80045, USA
| | - Anna P Malykhina
- Division of Urology, Department of Surgery, University of Colorado Denver,Anschutz Medical Campus, 12700 E 19th Ave, M/S C317, Aurora, CO, 80045, USA.
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Lamas JA, Rueda-Ruzafa L, Herrera-Pérez S. Ion Channels and Thermosensitivity: TRP, TREK, or Both? Int J Mol Sci 2019; 20:ijms20102371. [PMID: 31091651 PMCID: PMC6566417 DOI: 10.3390/ijms20102371] [Citation(s) in RCA: 58] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Revised: 05/03/2019] [Accepted: 05/07/2019] [Indexed: 11/16/2022] Open
Abstract
Controlling body temperature is a matter of life or death for most animals, and in mammals the complex thermoregulatory system is comprised of thermoreceptors, thermosensors, and effectors. The activity of thermoreceptors and thermoeffectors has been studied for many years, yet only recently have we begun to obtain a clear picture of the thermosensors and the molecular mechanisms involved in thermosensory reception. An important step in this direction was the discovery of the thermosensitive transient receptor potential (TRP) cationic channels, some of which are activated by increases in temperature and others by a drop in temperature, potentially converting the cells in which they are expressed into heat and cold receptors. More recently, the TWIK-related potassium (TREK) channels were seen to be strongly activated by increases in temperature. Hence, in this review we want to assess the hypothesis that both these groups of channels can collaborate, possibly along with other channels, to generate the wide range of thermal sensations that the nervous system is capable of handling.
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Affiliation(s)
- J Antonio Lamas
- Laboratory of Neuroscience, Biomedical Research Center (CINBIO), University of Vigo, 36310 Vigo, Spain.
| | - Lola Rueda-Ruzafa
- Laboratory of Neuroscience, Biomedical Research Center (CINBIO), University of Vigo, 36310 Vigo, Spain.
| | - Salvador Herrera-Pérez
- Laboratory of Neuroscience, Biomedical Research Center (CINBIO), University of Vigo, 36310 Vigo, Spain.
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Ramírez D, Bedoya M, Kiper AK, Rinné S, Morales-Navarro S, Hernández-Rodríguez EW, Sepúlveda FV, Decher N, González W. Structure/Activity Analysis of TASK-3 Channel Antagonists Based on a 5,6,7,8 tetrahydropyrido[4,3-d]pyrimidine. Int J Mol Sci 2019; 20:ijms20092252. [PMID: 31067753 PMCID: PMC6539479 DOI: 10.3390/ijms20092252] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2019] [Revised: 04/18/2019] [Accepted: 04/20/2019] [Indexed: 11/16/2022] Open
Abstract
TASK-3 potassium (K+) channels are highly expressed in the central nervous system, regulating the membrane potential of excitable cells. TASK-3 is involved in neurotransmitter action and has been identified as an oncogenic K+ channel. For this reason, the understanding of the action mechanism of pharmacological modulators of these channels is essential to obtain new therapeutic strategies. In this study we describe the binding mode of the potent antagonist PK-THPP into the TASK-3 channel. PK-THPP blocks TASK-1, the closest relative channel of TASK-3, with almost nine-times less potency. Our results confirm that the binding is influenced by the fenestrations state of TASK-3 channels and occurs when they are open. The binding is mainly governed by hydrophobic contacts between the blocker and the residues of the binding site. These interactions occur not only for PK-THPP, but also for the antagonist series based on 5,6,7,8 tetrahydropyrido[4,3-d]pyrimidine scaffold (THPP series). However, the marked difference in the potency of THPP series compounds such as 20b, 21, 22 and 23 (PK-THPP) respect to compounds such as 17b, inhibiting TASK-3 channels in the micromolar range is due to the presence of a hydrogen bond acceptor group that can establish interactions with the threonines of the selectivity filter.
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Affiliation(s)
- David Ramírez
- Instituto de Ciencias Biomédicas, Facultad de Ciencias de la Salud, Universidad Autónoma de Chile. El Llano Subercaseaux 2801-Piso 6, 7500912 Santiago, Chile.
| | - Mauricio Bedoya
- Centro de Bioinformática y Simulación Molecular (CBSM), Universidad de Talca. 1 Poniente No. 1141, 3460000 Talca, Chile.
| | - Aytug K Kiper
- Institute for Physiology and Pathophysiology, Vegetative Physiology, Philipps-University of Marburg, Deutschhausstraße 2, 35037 Marburg, Germany.
| | - Susanne Rinné
- Institute for Physiology and Pathophysiology, Vegetative Physiology, Philipps-University of Marburg, Deutschhausstraße 2, 35037 Marburg, Germany.
| | - Samuel Morales-Navarro
- Bachillerato en Ciencias, Facultad de Ciencias, Universidad Santo Tomás, Av. Circunvalación Poniente #1855, 3460000 Talca, Chile.
| | - Erix W Hernández-Rodríguez
- Centro de Bioinformática y Simulación Molecular (CBSM), Universidad de Talca. 1 Poniente No. 1141, 3460000 Talca, Chile.
- Escuela de Química y Farmacia. Facultad de Medicina. Universidad Católica del Maule, 3460000 Talca, Chile.
| | | | - Niels Decher
- Institute for Physiology and Pathophysiology, Vegetative Physiology, Philipps-University of Marburg, Deutschhausstraße 2, 35037 Marburg, Germany.
| | - Wendy González
- Centro de Bioinformática y Simulación Molecular (CBSM), Universidad de Talca. 1 Poniente No. 1141, 3460000 Talca, Chile.
- Millennium Nucleus of Ion Channels-Associated Diseases (MiNICAD), Universidad de Talca, 3460000 Talca, Chile.
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Brennecke JT, de Groot BL. Mechanism of Mechanosensitive Gating of the TREK-2 Potassium Channel. Biophys J 2019; 114:1336-1343. [PMID: 29590591 DOI: 10.1016/j.bpj.2018.01.030] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2017] [Revised: 01/04/2018] [Accepted: 01/29/2018] [Indexed: 02/06/2023] Open
Abstract
The mechanism of mechanosensitive gating of ion channels underlies many physiological processes, including the sensations of touch, hearing, and pain perception. TREK-2 is the best-studied mechanosensitive member of the two-pore domain potassium channel family. Apart from pressure sensing, it responds to a diverse range of stimuli. Two states, termed "up" and "down," are known from x-ray structural crystallographic studies and have been suggested to differ in conductance. However, the structural details of the gating behavior are largely unknown. In this work, we used molecular dynamics simulations to study the conductance of the states as well as the effect of mechanical membrane stretch on the channel. We find that the down state is less conductive than the up state. The introduction of membrane stretch in the simulations shifts the state of the channel toward an up configuration, independent of the starting configuration, and also increases its conductance. The correlation of the selectivity filter state and the conductance supports a model in which the selectivity filter gates by a carbonyl flip. This gate is stabilized by the pore helices. We suggest a modulation of these helices by an interface to the transmembrane helices. Membrane pressure changes the conformation of the transmembrane helices directly and consequently also influences the channel conductance.
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Affiliation(s)
- Julian T Brennecke
- Department of Theoretical and Computational Biophysics, Computational Biomolecular Dynamics Group, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany
| | - Bert L de Groot
- Department of Theoretical and Computational Biophysics, Computational Biomolecular Dynamics Group, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany.
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42
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Lamas JA, Fernández-Fernández D. Tandem pore TWIK-related potassium channels and neuroprotection. Neural Regen Res 2019; 14:1293-1308. [PMID: 30964046 PMCID: PMC6524494 DOI: 10.4103/1673-5374.253506] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
TWIK-related potassium channels (TREK) belong to a subfamily of the two-pore domain potassium channels family with three members, TREK1, TREK2 and TWIK-related arachidonic acid-activated potassium channels. The two-pore domain potassium channels is the last big family of channels being discovered, therefore it is not surprising that most of the information we know about TREK channels predominantly comes from the study of heterologously expressed channels. Notwithstanding, in this review we pay special attention to the limited amount of information available on native TREK-like channels and real neurons in relation to neuroprotection. Mainly we focus on the role of free fatty acids, lysophospholipids and other neuroprotective agents like riluzole in the modulation of TREK channels, emphasizing on how important this modulation may be for the development of new therapies against neuropathic pain, depression, schizophrenia, epilepsy, ischemia and cardiac complications.
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Affiliation(s)
- J Antonio Lamas
- Laboratory of Neuroscience, Biomedical Research Center (CINBIO), University of Vigo, Vigo, Galicia, Spain
| | - Diego Fernández-Fernández
- Laboratory of Neuroscience, Biomedical Research Center (CINBIO), University of Vigo, Vigo, Galicia, Spain
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43
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Hernández-Araiza I, Morales-Lázaro SL, Canul-Sánchez JA, Islas LD, Rosenbaum T. Role of lysophosphatidic acid in ion channel function and disease. J Neurophysiol 2018; 120:1198-1211. [PMID: 29947596 DOI: 10.1152/jn.00226.2018] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Lysophosphatidic acid (LPA) is a bioactive phospholipid that exhibits a wide array of functions that include regulation of protein synthesis and adequate development of organisms. LPA is present in the membranes of cells and in the serum of several mammals and has also been shown to participate importantly in pathophysiological conditions. For several decades it was known that LPA produces some of its effects in cells through its interaction with specific G protein-coupled receptors, which in turn are responsible for signaling pathways that regulate cellular function. Among the target proteins for LPA receptors are ion channels that modulate diverse aspects of the physiology of cells and organs where they are expressed. However, recent studies have begun to unveil direct effects of LPA on ion channels, highlighting this phospholipid as a direct agonist and adding to the knowledge of the field of lipid-protein interactions. Moreover, the roles of LPA in pathophysiological conditions associated with the function of some ion channels have also begun to be clarified, and molecular mechanisms have been identified. This review focuses on the effects of LPA on ion channel function under normal and pathological conditions and highlights our present knowledge of the mechanisms by which it regulates the function and expression of N- and T-type Ca++ channels; M-type K+ channel and inward rectifier K+ channel subunit 2.1; transient receptor potential (TRP) melastatin 2, TRP vanilloid 1, and TRP ankyrin 1 channels; and TWIK-related K+ channel 1 (TREK-1), TREK-2, TWIK-related spinal cord K+ channel (TRESK), and TWIK-related arachidonic acid-stimulated K+ channel (TRAAK).
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Affiliation(s)
- Ileana Hernández-Araiza
- Departamento de Neurociencia Cognitiva, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México , Mexico City, Mexico
| | - Sara L Morales-Lázaro
- Departamento de Neurociencia Cognitiva, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México , Mexico City, Mexico
| | - Jesús Aldair Canul-Sánchez
- Departamento de Neurociencia Cognitiva, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México , Mexico City, Mexico
| | - León D Islas
- Departamento de Fisiología, Facultad de Medicina, Universidad Nacional Autónoma de México , Mexico City, Mexico
| | - Tamara Rosenbaum
- Departamento de Neurociencia Cognitiva, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México , Mexico City, Mexico
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44
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Fernández-Fernández D, Cadaveira-Mosquera A, Rueda-Ruzafa L, Herrera-Pérez S, Veale EL, Reboreda A, Mathie A, Lamas JA. Activation of TREK currents by riluzole in three subgroups of cultured mouse nodose ganglion neurons. PLoS One 2018; 13:e0199282. [PMID: 29928032 PMCID: PMC6013220 DOI: 10.1371/journal.pone.0199282] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2017] [Accepted: 06/05/2018] [Indexed: 01/12/2023] Open
Abstract
Two-pore domain potassium channels (K2P) constitute major candidates for the regulation of background potassium currents in mammalian cells. Channels of the TREK subfamily are also well positioned to play an important role in sensory transduction due to their sensitivity to a large number of physiological and physical stimuli (pH, mechanical, temperature). Following our previous report describing the molecular expression of different K2P channels in the vagal sensory system, here we confirm that TREK channels are functionally expressed in neurons from the mouse nodose ganglion (mNG). Neurons were subdivided into three groups (A, Ah and C) based on their response to tetrodotoxin and capsaicin. Application of the TREK subfamily activator riluzole to isolated mNG neurons evoked a concentration-dependent outward current in the majority of cells from all the three subtypes studied. Riluzole increased membrane conductance and hyperpolarized the membrane potential by approximately 10 mV when applied to resting neurons. The resting potential was similar in all three groups, but C cells were clearly less excitable and showed smaller hyperpolarization-activated currents at -100 mV and smaller sustained currents at -30 mV. Our results indicate that the TREK subfamily of K2P channels might play an important role in the maintenance of the resting membrane potential in sensory neurons of the autonomic nervous system, suggesting its participation in the modulation of vagal reflexes.
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Affiliation(s)
- Diego Fernández-Fernández
- Department of Functional Biology and Health Sciences, Faculty of Biology–CINBIO, University of Vigo, Vigo, Galicia, Spain
- * E-mail: (DFF); (JAL)
| | - Alba Cadaveira-Mosquera
- Department of Functional Biology and Health Sciences, Faculty of Biology–CINBIO, University of Vigo, Vigo, Galicia, Spain
| | - Lola Rueda-Ruzafa
- Department of Functional Biology and Health Sciences, Faculty of Biology–CINBIO, University of Vigo, Vigo, Galicia, Spain
| | - Salvador Herrera-Pérez
- Department of Functional Biology and Health Sciences, Faculty of Biology–CINBIO, University of Vigo, Vigo, Galicia, Spain
| | - Emma L. Veale
- Medway School of Pharmacy, University of Kent, Chatham Maritime, Kent, United Kingdom
| | - Antonio Reboreda
- Department of Functional Biology and Health Sciences, Faculty of Biology–CINBIO, University of Vigo, Vigo, Galicia, Spain
| | - Alistair Mathie
- Medway School of Pharmacy, University of Kent, Chatham Maritime, Kent, United Kingdom
| | - J. Antonio Lamas
- Department of Functional Biology and Health Sciences, Faculty of Biology–CINBIO, University of Vigo, Vigo, Galicia, Spain
- * E-mail: (DFF); (JAL)
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45
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Hoffstaetter LJ, Bagriantsev SN, Gracheva EO. TRPs et al.: a molecular toolkit for thermosensory adaptations. Pflugers Arch 2018; 470:745-759. [PMID: 29484488 PMCID: PMC5945325 DOI: 10.1007/s00424-018-2120-5] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2017] [Revised: 01/03/2018] [Accepted: 02/05/2018] [Indexed: 12/19/2022]
Abstract
The ability to sense temperature is crucial for the survival of an organism. Temperature influences all biological operations, from rates of metabolic reactions to protein folding, and broad behavioral functions, from feeding to breeding, and other seasonal activities. The evolution of specialized thermosensory adaptations has enabled animals to inhabit extreme temperature niches and to perform specific temperature-dependent behaviors. The function of sensory neurons depends on the participation of various types of ion channels. Each of the channels involved in neuronal excitability, whether through the generation of receptor potential, action potential, or the maintenance of the resting potential have temperature-dependent properties that can tune the neuron's response to temperature stimuli. Since the function of all proteins is affected by temperature, animals need adaptations not only for detecting different temperatures, but also for maintaining sensory ability at different temperatures. A full understanding of the molecular mechanism of thermosensation requires an investigation of all channel types at each step of thermosensory transduction. A fruitful avenue of investigation into how different molecules can contribute to the fine-tuning of temperature sensitivity is to study the specialized adaptations of various species. Given the diversity of molecular participants at each stage of sensory transduction, animals have a toolkit of channels at their disposal to adapt their thermosensitivity to their particular habitats or behavioral circumstances.
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Affiliation(s)
- Lydia J Hoffstaetter
- Department of Cellular and Molecular Physiology, Yale University School of Medicine, 333 Cedar Street, New Haven, CT, 06520-8026, USA
- Department of Neuroscience, Yale University School of Medicine, 333 Cedar Street, New Haven, CT, 06520-8026, USA
- Program in Cellular Neuroscience, Neurodegeneration and Repair, Yale University School of Medicine, 333 Cedar Street, New Haven, CT, 06520-8026, USA
| | - Sviatoslav N Bagriantsev
- Department of Cellular and Molecular Physiology, Yale University School of Medicine, 333 Cedar Street, New Haven, CT, 06520-8026, USA
| | - Elena O Gracheva
- Department of Cellular and Molecular Physiology, Yale University School of Medicine, 333 Cedar Street, New Haven, CT, 06520-8026, USA.
- Department of Neuroscience, Yale University School of Medicine, 333 Cedar Street, New Haven, CT, 06520-8026, USA.
- Program in Cellular Neuroscience, Neurodegeneration and Repair, Yale University School of Medicine, 333 Cedar Street, New Haven, CT, 06520-8026, USA.
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Loganathan K, Moriya S, Sivalingam M, Ng KW, Parhar IS. Sequence and localization of kcnk10a in the brain of adult zebrafish (Danio rerio). J Chem Neuroanat 2017; 86:92-99. [DOI: 10.1016/j.jchemneu.2017.10.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2017] [Revised: 08/23/2017] [Accepted: 10/21/2017] [Indexed: 01/16/2023]
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47
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Decher N, Kiper AK, Rinné S. Stretch-activated potassium currents in the heart: Focus on TREK-1 and arrhythmias. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2017; 130:223-232. [PMID: 28526352 DOI: 10.1016/j.pbiomolbio.2017.05.005] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2017] [Revised: 05/09/2017] [Accepted: 05/15/2017] [Indexed: 12/26/2022]
Abstract
This review focuses on the role and the molecular candidates of the cardiac stretch-activated potassium current (SAK). The functional properties of the two-pore domain potassium (K2P) channel TREK-1, a major candidate for the cardiac SAK, are analyzed and the molecular mechanism of stretch-activation in K2P potassium channels is discussed. Furthermore, the functional modulation of TREK-1 by different cardiac interaction partners, as well as evidence for the functional role of the stretch-dependent TREK-1 and its putative subunits in the heart is reviewed. In addition, we summarize the recent evidence that TREK-1 is involved in the pathogenesis of human cardiac arrhythmias.
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Affiliation(s)
- Niels Decher
- Institute for Physiology and Pathophysiology, AG Vegetative Physiology, Deutschhausstrasse 1-2, 35037 Marburg, Germany.
| | - Aytug K Kiper
- Institute for Physiology and Pathophysiology, AG Vegetative Physiology, Deutschhausstrasse 1-2, 35037 Marburg, Germany
| | - Susanne Rinné
- Institute for Physiology and Pathophysiology, AG Vegetative Physiology, Deutschhausstrasse 1-2, 35037 Marburg, Germany
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48
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Masuda Y, Yokose S, Sakagami H. Gene Expression Analysis of Cultured Rat-Endothelial Cells after Nd:YAG Laser Irradiation by Affymetrix GeneChip Array. ACTA ACUST UNITED AC 2017; 31:51-54. [PMID: 28064220 DOI: 10.21873/invivo.11024] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2016] [Revised: 12/16/2016] [Accepted: 12/21/2016] [Indexed: 12/14/2022]
Abstract
Endothelial cells and dental pulp cells enhance osteo-/odontogenic and angiogenic differentiation. In our previous study, rat pulp cells migrated to Nd:YAG laser-irradiated endothelial cells in an insert cell culture system. The purpose of this study was to examine the possible changes in the gene expression of cultured rat aortic endothelial cells after Nd:YAG laser irradiation using affymetrix GeneChip Array. Total RNA was extracted from the cells at 5 h after laser irradiation. Gene expressions were evaluated by DNA array chip. Up-regulated genes were related to cell migration and cell structure (membrane stretch, actin regulation and junctional complexes), neurotransmission and inflammation. Heat-shock 70 kDa protein (Hsp70) was related to the development of tooth germ. This study offers candidate genes for understanding the relationship between the laser-stimulated endothelial cells and dental pulp cells.
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Affiliation(s)
- Yoshiko Masuda
- Meikai Pharmaco-Medical Laboratory (MPL), Meikai University School of Dentistry, Saitama, Japan
| | - Satoshi Yokose
- Division of Endodontics and Operative, Meikai University School of Dentistry, Saitama, Japan
| | - Hiroshi Sakagami
- Meikai Pharmaco-Medical Laboratory (MPL), Meikai University School of Dentistry, Saitama, Japan.,Division of Pharmacology, Meikai University School of Dentistry, Saitama, Japan
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Kinetic properties and adrenergic control of TREK-2-like channels in rat medial prefrontal cortex (mPFC) pyramidal neurons. Brain Res 2017; 1665:95-104. [PMID: 28438532 DOI: 10.1016/j.brainres.2017.04.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2016] [Revised: 03/03/2017] [Accepted: 04/14/2017] [Indexed: 02/01/2023]
Abstract
TREK-2-like channels were identified on the basis of electrophysiological and pharmacological tests performed on freshly isolated and enzymatically/mechanically dispersed pyramidal neurons of the rat medial prefrontal cortex (mPFC). Single-channel currents were recorded in cell-attached configuration and the impact of adrenergic receptors (α1, α2, β) stimulation on spontaneously appearing TREK-2-like channel activity was tested. The obtained results indicate that noradrenaline decreases the mean open probability of TREK-2-like channel currents by activation of β1 but not of α1- and α2-adrenergic receptors. Mean open time and channel conductance were not affected. The system of intracellular signaling pathways depends on the activation of protein kinase A. We also show that adrenergic control of TREK-2-like channel currents by adrenergic receptors was similar in pyramidal neurons isolated from young, adolescent, and adult rats. Immunofluorescent confocal scans of mPFC slices confirmed the presence of the TREK-2 protein, which was abundant in layer V pyramidal neurons. The role of TREK-2-like channel control by adrenergic receptors is discussed.
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50
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Dadi PK, Vierra NC, Days E, Dickerson MT, Vinson PN, Weaver CD, Jacobson DA. Selective Small Molecule Activators of TREK-2 Channels Stimulate Dorsal Root Ganglion c-Fiber Nociceptor Two-Pore-Domain Potassium Channel Currents and Limit Calcium Influx. ACS Chem Neurosci 2017; 8:558-568. [PMID: 27805811 PMCID: PMC5901755 DOI: 10.1021/acschemneuro.6b00301] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
The two-pore-domain potassium (K2P) channel TREK-2 serves to modulate plasma membrane potential in dorsal root ganglia c-fiber nociceptors, which tunes electrical excitability and nociception. Thus, TREK-2 channels are considered a potential therapeutic target for treating pain; however, there are currently no selective pharmacological tools for TREK-2 channels. Here we report the identification of the first TREK-2 selective activators using a high-throughput fluorescence-based thallium (Tl+) flux screen (HTS). An initial pilot screen with a bioactive lipid library identified 11-deoxy prostaglandin F2α as a potent activator of TREK-2 channels (EC50 ≈ 0.294 μM), which was utilized to optimize the TREK-2 Tl+ flux assay (Z' = 0.752). A HTS was then performed with 76 575 structurally diverse small molecules. Many small molecules that selectively activate TREK-2 were discovered. As these molecules were able to activate single TREK-2 channels in excised membrane patches, they are likely direct TREK-2 activators. Furthermore, TREK-2 activators reduced primary dorsal root ganglion (DRG) c-fiber Ca2+ influx. Interestingly, some of the selective TREK-2 activators such as 11-deoxy prostaglandin F2α were found to inhibit the K2P channel TREK-1. Utilizing chimeric channels containing portions of TREK-1 and TREK-2, the region of the TREK channels that allows for either small molecule activation or inhibition was identified. This region lies within the second pore domain containing extracellular loop and is predicted to play an important role in modulating TREK channel activity. Moreover, the selective TREK-2 activators identified in this HTS provide important tools for assessing human TREK-2 channel function and investigating their therapeutic potential for treating chronic pain.
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Affiliation(s)
- Prasanna K. Dadi
- Department of Molecular Physiology and Biophysics, Vanderbilt University Medical Center, Nashville, Tennessee 37232, United States
| | - Nicholas C. Vierra
- Department of Molecular Physiology and Biophysics, Vanderbilt University Medical Center, Nashville, Tennessee 37232, United States
| | - Emily Days
- Institute of Chemical Biology, Vanderbilt University Medical Center, Nashville, Tennessee 37232, United States
| | - Matthew T. Dickerson
- Department of Molecular Physiology and Biophysics, Vanderbilt University Medical Center, Nashville, Tennessee 37232, United States
| | - Paige N. Vinson
- Department of Biochemistry, Vanderbilt University Medical Center, Nashville, Tennessee 37232, United States
| | - C. David Weaver
- Department of Pharmacology, Vanderbilt University Medical Center, Nashville, Tennessee 37232, United States
| | - David A Jacobson
- Department of Molecular Physiology and Biophysics, Vanderbilt University Medical Center, Nashville, Tennessee 37232, United States
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