1
|
A novel insight into differential expression profiles of sporadic cerebral cavernous malformation patients with different symptoms. Sci Rep 2021; 11:19351. [PMID: 34588521 PMCID: PMC8481309 DOI: 10.1038/s41598-021-98647-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Accepted: 09/09/2021] [Indexed: 02/08/2023] Open
Abstract
Cerebral cavernous malformation (CCM) is a vascular lesion of the central nervous system that may lead to distinct symptoms among patients including cerebral hemorrhages, epileptic seizures, focal neurologic deficits, and/or headaches. Disease-related mutations were identified previously in one of the three CCM genes: CCM1, CCM2, and CCM3. However, the rate of these mutations in sporadic cases is relatively low, and new studies report that mutations in CCM genes may not be sufficient to initiate the lesions. Despite the growing body of research on CCM, the underlying molecular mechanism has remained largely elusive. In order to provide a novel insight considering the specific manifested symptoms, CCM patients were classified into two groups (as Epilepsy and Hemorrhage). Since the studied patients experience various symptoms, we hypothesized that the underlying cause for the disease may also differ between those groups. To this end, the respective transcriptomes were compared to the transcriptomes of the control brain tissues and among each other. This resulted into the identification of the differentially expressed coding genes and the delineation of the corresponding differential expression profile for each comparison. Notably, some of those differentially expressed genes were previously implicated in epilepsy, cell structure formation, and cell metabolism. However, no CCM1-3 gene deregulation was detected. Interestingly, we observed that when compared to the normal controls, the expression of some identified genes was only significantly altered either in Epilepsy (EGLN1, ELAVL4, and NFE2l2) or Hemorrhage (USP22, EYA1, SIX1, OAS3, SRMS) groups. To the best of our knowledge, this is the first such effort focusing on CCM patients with epileptic and hemorrhagic symptoms with the purpose of uncovering the potential CCM-related genes. It is also the first report that presents a gene expression dataset on Turkish CCM patients. The results suggest that the new candidate genes should be explored to further elucidate the CCM pathology. Overall, this work constitutes a step towards the identification of novel potential genetic targets for the development of possible future therapies.
Collapse
|
2
|
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.
Collapse
|
3
|
Pavinato L, Nematian-Ardestani E, Zonta A, De Rubeis S, Buxbaum J, Mancini C, Bruselles A, Tartaglia M, Pessia M, Tucker SJ, D’Adamo MC, Brusco A. KCNK18 Biallelic Variants Associated with Intellectual Disability and Neurodevelopmental Disorders Alter TRESK Channel Activity. Int J Mol Sci 2021; 22:ijms22116064. [PMID: 34199759 PMCID: PMC8200030 DOI: 10.3390/ijms22116064] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Revised: 05/30/2021] [Accepted: 06/01/2021] [Indexed: 12/19/2022] Open
Abstract
The TWIK-related spinal cord potassium channel (TRESK) is encoded by KCNK18, and variants in this gene have previously been associated with susceptibility to familial migraine with aura (MIM #613656). A single amino acid substitution in the same protein, p.Trp101Arg, has also been associated with intellectual disability (ID), opening the possibility that variants in this gene might be involved in different disorders. Here, we report the identification of KCNK18 biallelic missense variants (p.Tyr163Asp and p.Ser252Leu) in a family characterized by three siblings affected by mild-to-moderate ID, autism spectrum disorder (ASD) and other neurodevelopment-related features. Functional characterization of the variants alone or in combination showed impaired channel activity. Interestingly, Ser252 is an important regulatory site of TRESK, suggesting that alteration of this residue could lead to additive downstream effects. The functional relevance of these mutations and the observed co-segregation in all the affected members of the family expand the clinical variability associated with altered TRESK function and provide further insight into the relationship between altered function of this ion channel and human disease.
Collapse
Affiliation(s)
- Lisa Pavinato
- Department of Medical Sciences, University of Turin, 10126 Turin, Italy;
- Center for Molecular Medicine Cologne, Institute of Human Genetics, University of Cologne, 50931 Cologne, Germany
| | - Ehsan Nematian-Ardestani
- Department of Physiology and Biochemistry, Faculty of Medicine and Surgery, University of Malta, MSD-2080 Msida, Malta; (E.N.-A.); (M.P.)
| | - Andrea Zonta
- Unit of Medical Genetics, “Città della Salute e della Scienza” University Hospital, 10126 Turin, Italy;
| | - Silvia De Rubeis
- Seaver Autism Center for Research and Treatment, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA; (S.D.R.); (J.B.)
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
- The Mindich Child Health and Development Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
- Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Joseph Buxbaum
- Seaver Autism Center for Research and Treatment, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA; (S.D.R.); (J.B.)
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
- The Mindich Child Health and Development Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
- Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
- Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Cecilia Mancini
- Genetics and Rare Diseases Research Division, Ospedale Pediatrico Bambino Gesù, IRCCS, 00165 Rome, Italy; (C.M.); (M.T.)
| | - Alessandro Bruselles
- Department of Oncology and Molecular Medicine, Istituto Superiore di Sanità, 00161 Rome, Italy;
| | - Marco Tartaglia
- Genetics and Rare Diseases Research Division, Ospedale Pediatrico Bambino Gesù, IRCCS, 00165 Rome, Italy; (C.M.); (M.T.)
| | - Mauro Pessia
- Department of Physiology and Biochemistry, Faculty of Medicine and Surgery, University of Malta, MSD-2080 Msida, Malta; (E.N.-A.); (M.P.)
- Department of Physiology, College of Medicine and Health Sciences, United Arab Emirates University, Al Ain P.O. Box 17666, United Arab Emirates
| | - Stephen J. Tucker
- Clarendon Laboratory, Department of Physics, University of Oxford, Oxford OX1 4BH, UK;
| | - Maria Cristina D’Adamo
- Department of Physiology and Biochemistry, Faculty of Medicine and Surgery, University of Malta, MSD-2080 Msida, Malta; (E.N.-A.); (M.P.)
- Correspondence: (M.C.D.); (A.B.)
| | - Alfredo Brusco
- Department of Medical Sciences, University of Turin, 10126 Turin, Italy;
- Unit of Medical Genetics, “Città della Salute e della Scienza” University Hospital, 10126 Turin, Italy;
- Correspondence: (M.C.D.); (A.B.)
| |
Collapse
|
4
|
Walsh Y, Leach M, Veale EL, Mathie A. Block of TREK and TRESK K2P channels by lamotrigine and two derivatives sipatrigine and CEN-092. Biochem Biophys Rep 2021; 26:101021. [PMID: 34041373 PMCID: PMC8144350 DOI: 10.1016/j.bbrep.2021.101021] [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: 03/26/2021] [Revised: 04/29/2021] [Accepted: 05/07/2021] [Indexed: 11/30/2022] Open
Abstract
TREK and TRESK K2P channels are widely expressed in the nervous system, particularly in sensory neurons, where they regulate neuronal excitability. In this study, using whole-cell patch-clamp electrophysiology, we characterise the inhibitory effect of the anticonvulsant lamotrigine and two derivatives, sipatrigine and 3,5-diamino-6-(3,5-bistrifluoromethylphenyl)-1,2,4-triazine (CEN-092) on these channels. Sipatrigine was found to be a more effective inhibitor than lamotrigine of TREK-1, TREK-2 and TRESK channels. Sipatrigine was slightly more potent on TREK-1 channels (EC50 = 16 μM) than TRESK (EC50 = 34 μM) whereas lamotrigine was equally effective on TREK-1 and TRESK. Sipatrigine was less effective on a short isoform of TREK-2, suggesting the N terminus of the channel is important for both inhibition and subsequent over-recovery. Inhibition of TREK-1 and TREK-2 channels by sipatrigine was reduced by mutation of a leucine residue associated with the norfluoxetine binding site on these channels (L289A and L320A on TREK-1 and TREK-2, respectively) but these did not affect inhibition by lamotrigine. Inhibition of TRESK by sipatrigine and lamotrigine was attenuated by mutation of bulky phenylalanine residues (F145A and F352A) in the inner pore helix. However, phosphorylation mutations did not alter the effect of sipatrigine. CEN-092 was a more effective inhibitor of TRESK channels than TREK-1 channels. It is concluded that lamotrigine, sipatrigine and CEN-092 are all inhibitors of TREK and TRESK channels but do not greatly discriminate between them. The actions of these compounds may contribute to their current and potential use in the treatment of pain and depression. Lamotrigine blocks TREK and TRESK potassium channels at clinical concentrations. Sipatrigine is more effective than lamotrigine at blocking TREK and TRESK channels. Mutation of norfluoxetine binding site on TREK channels attenuates sipatrigine block. Residues in the inner pore region of TRESK channels regulate sipatrigine block. The novel lamotrigine derivative, CEN-092, blocks TRESK channels.
Collapse
Affiliation(s)
- Yvonne Walsh
- Medway School of Pharmacy, University of Kent and University of Greenwich, Central Avenue, Chatham Maritime, ME4 4TB, UK
- University of Greenwich, Central Avenue, Chatham Maritime, ME4 4TB, UK
| | - Michael Leach
- University of Greenwich, Central Avenue, Chatham Maritime, ME4 4TB, UK
| | - Emma L. Veale
- Medway School of Pharmacy, University of Kent and University of Greenwich, Central Avenue, Chatham Maritime, ME4 4TB, UK
| | - Alistair Mathie
- Medway School of Pharmacy, University of Kent and University of Greenwich, Central Avenue, Chatham Maritime, ME4 4TB, UK
- School of Engineering, Arts, Science and Technology, University of Suffolk, Waterfront Building, Neptune Quay, Ipswich, IP4 1QJ, UK
- Corresponding author.Medway School of Pharmacy, University of Kent and University of Greenwich, Central Avenue, Chatham Maritime, ME4 4TB, UK.
| |
Collapse
|
5
|
Kim GT, Siregar AS, Kim EJ, Lee ES, Nyiramana MM, Woo MS, Hah YS, Han J, Kang D. Upregulation of TRESK Channels Contributes to Motor and Sensory Recovery after Spinal Cord Injury. Int J Mol Sci 2020; 21:ijms21238997. [PMID: 33256222 PMCID: PMC7731147 DOI: 10.3390/ijms21238997] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Revised: 11/22/2020] [Accepted: 11/24/2020] [Indexed: 12/27/2022] Open
Abstract
TWIK (tandem-pore domain weak inward rectifying K+)-related spinal cord K+ channel (TRESK), a member of the two-pore domain K+ channel family, is abundantly expressed in dorsal root ganglion (DRG) neurons. It is well documented that TRESK expression is changed in several models of peripheral nerve injury, resulting in a shift in sensory neuron excitability. However, the role of TRESK in the model of spinal cord injury (SCI) has not been fully understood. This study investigates the role of TRESK in a thoracic spinal cord contusion model, and in transgenic mice overexpressed with the TRESK gene (TGTRESK). Immunostaining analysis showed that TRESK was expressed in the dorsal and ventral neurons of the spinal cord. The TRESK expression was increased by SCI in both dorsal and ventral neurons. TRESK mRNA expression was upregulated in the spinal cord and DRG isolated from the ninth thoracic (T9) spinal cord contusion rats. The expression was significantly upregulated in the spinal cord below the injury site at acute time points (6, 24, and 48 h) after SCI (p < 0.05). In addition, TRESK expression was markedly increased in DRGs below and adjacent to the injury site. TRESK was expressed in inflammatory cells. In addition, the number and fluorescence intensity of TRESK-positive neurons increased in the dorsal and ventral horns of the spinal cord after SCI. TGTRESK SCI mice showed faster paralysis recovery and higher mechanical threshold compared to wild-type (WT)-SCI mice. TGTRESK mice showed lower TNF-α concentrations in the blood than WT mice. In addition, IL-1β concentration and apoptotic signals in the caudal spinal cord and DRG were significantly decreased in TGTRESK SCI mice compared to WT-SCI mice (p < 0.05). These results indicate that TRESK upregulated following SCI contributes to the recovery of paralysis and mechanical pain threshold by suppressing the excitability of motor and sensory neurons and inflammatory and apoptotic processes.
Collapse
Affiliation(s)
- Gyu-Tae Kim
- Department of Physiology and Institute of Health Sciences, College of Medicine, Gyeongsang National University, Jinju 52727, Korea; (G.-T.K.); (A.S.S.); (E.-J.K.); (M.M.N.); (M.S.W.); (J.H.)
| | - Adrian S. Siregar
- Department of Physiology and Institute of Health Sciences, College of Medicine, Gyeongsang National University, Jinju 52727, Korea; (G.-T.K.); (A.S.S.); (E.-J.K.); (M.M.N.); (M.S.W.); (J.H.)
- Department of Convergence Medical Science, Gyeongsang National University, Jinju 52727, Korea
| | - Eun-Jin Kim
- Department of Physiology and Institute of Health Sciences, College of Medicine, Gyeongsang National University, Jinju 52727, Korea; (G.-T.K.); (A.S.S.); (E.-J.K.); (M.M.N.); (M.S.W.); (J.H.)
| | - Eun-Shin Lee
- Department of Rehabilitation Medicine, College of Medicine, Gyeongsang National University, Jinju 52727, Korea;
| | - Marie Merci Nyiramana
- Department of Physiology and Institute of Health Sciences, College of Medicine, Gyeongsang National University, Jinju 52727, Korea; (G.-T.K.); (A.S.S.); (E.-J.K.); (M.M.N.); (M.S.W.); (J.H.)
- Department of Convergence Medical Science, Gyeongsang National University, Jinju 52727, Korea
| | - Min Seok Woo
- Department of Physiology and Institute of Health Sciences, College of Medicine, Gyeongsang National University, Jinju 52727, Korea; (G.-T.K.); (A.S.S.); (E.-J.K.); (M.M.N.); (M.S.W.); (J.H.)
| | - Young-Sool Hah
- Biomedical Research Institute, Gyeongsang National University Hospital, Jinju 52727, Korea;
| | - Jaehee Han
- Department of Physiology and Institute of Health Sciences, College of Medicine, Gyeongsang National University, Jinju 52727, Korea; (G.-T.K.); (A.S.S.); (E.-J.K.); (M.M.N.); (M.S.W.); (J.H.)
| | - Dawon Kang
- Department of Physiology and Institute of Health Sciences, College of Medicine, Gyeongsang National University, Jinju 52727, Korea; (G.-T.K.); (A.S.S.); (E.-J.K.); (M.M.N.); (M.S.W.); (J.H.)
- Department of Convergence Medical Science, Gyeongsang National University, Jinju 52727, Korea
- Correspondence: ; Tel.: +82-55-772-8044
| |
Collapse
|
6
|
The Background K + Channel TRESK in Sensory Physiology and Pain. Int J Mol Sci 2020; 21:ijms21155206. [PMID: 32717813 PMCID: PMC7432782 DOI: 10.3390/ijms21155206] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Revised: 07/20/2020] [Accepted: 07/21/2020] [Indexed: 12/18/2022] Open
Abstract
TRESK belongs to the K2P family of potassium channels, also known as background or leak potassium channels due to their biophysical properties and their role regulating membrane potential of cells. Several studies to date have highlighted the role of TRESK in regulating the excitability of specific subtypes of sensory neurons. These findings suggest TRESK could be involved in pain sensitivity. Here, we review the different evidence available that involves the channel in pain and sensory perception, from studies knocking out the channel or overexpressing it to identified mutations that link the channel to migraine pain. In addition, the therapeutic possibilities are discussed, as targeting the channel seems an interesting therapeutic approach to reduce nociceptor activation and to decrease pain.
Collapse
|
7
|
Buch D, Chabriat H. Lamotrigine in the Prevention of Migraine With Aura: A Narrative Review. Headache 2019; 59:1187-1197. [PMID: 31468532 DOI: 10.1111/head.13615] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/31/2019] [Indexed: 01/03/2023]
Abstract
BACKGROUND Lamotrigine is not recommended in the prevention of migraine in general but some reports suggest that it might be effective for treating specifically migraine with aura (MA). This review aims to summarize the related data from the literature and to better understand this discrepancy. METHODS All reports from the literature related to the use of lamotrigine in migraine with or without aura published prior to February 2019 found using PUBMED and the 2 keywords "migraine" AND "lamotrigine" were reviewed. Original studies, published in full, systematic reviews, and all case reports were synthetized. We also examined the risk profile, pharmacokinetics, and mode of action of lamotrigine in view of the presumed mechanism of MA. RESULTS Lamotrigine was tested in different populations of migraineurs, but previous studies had small sample sizes (n < 35) and might not have been powered enough for detecting a potential benefit of lamotrigine in MA. Accumulating data suggest that the drug can reduce both the frequency and severity of aura symptoms in multiple conditions and is well tolerated. CONCLUSION Lamotrigine appears promising for treating attacks of MA and related clinical manifestations because of its high potential of efficacy, low-risk profile, and cost. Additional studies are needed for testing lamotrigine in patients with MA.
Collapse
Affiliation(s)
- Dan Buch
- Neurology Department, DHU Neuro-Vasc, Hopital Lariboisière, Paris, France
| | - Hugues Chabriat
- Neurology Department, DHU Neuro-Vasc, Hopital Lariboisière, Paris, France.,INSERM U1161, Université Denis Diderot, Paris, France
| |
Collapse
|
8
|
Pergel E, Lengyel M, Enyedi P, Czirják G. TRESK (K2P18.1) Background Potassium Channel Is Activated by Novel-Type Protein Kinase C via Dephosphorylation. Mol Pharmacol 2019; 95:661-672. [DOI: 10.1124/mol.119.116269] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Accepted: 04/04/2019] [Indexed: 12/14/2022] Open
|
9
|
Lengyel M, Erdélyi F, Pergel E, Bálint-Polonka Á, Dobolyi A, Bozsaki P, Dux M, Király K, Hegedűs T, Czirják G, Mátyus P, Enyedi P. Chemically Modified Derivatives of the Activator Compound Cloxyquin Exert Inhibitory Effect on TRESK (K2P18.1) Background Potassium Channel. Mol Pharmacol 2019; 95:652-660. [DOI: 10.1124/mol.118.115626] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2018] [Accepted: 04/09/2019] [Indexed: 01/01/2023] Open
|
10
|
Yang Y, Li S, Jin ZR, Jing HB, Zhao HY, Liu BH, Liang YJ, Liu LY, Cai J, Wan Y, Xing GG. Decreased abundance of TRESK two-pore domain potassium channels in sensory neurons underlies the pain associated with bone metastasis. Sci Signal 2018; 11. [DOI: 10.1126/scisignal.aao5150] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/29/2023]
Abstract
Bone metastasis–associated VEGF suppresses neuronal K
+
channels and increases pain in rats.
Collapse
Affiliation(s)
- Yue Yang
- Department of Neurobiology, School of Basic Medical Sciences and Neuroscience Research Institute, Peking University, Beijing 100083, China
- Key Laboratory for Neuroscience, Ministry of Education of China and National Committee of Health and Family Planning of China, Peking University, Beijing 100083, China
| | - Song Li
- Department of Neurobiology, School of Basic Medical Sciences and Neuroscience Research Institute, Peking University, Beijing 100083, China
- Key Laboratory for Neuroscience, Ministry of Education of China and National Committee of Health and Family Planning of China, Peking University, Beijing 100083, China
| | - Zi-Run Jin
- Department of Neurobiology, School of Basic Medical Sciences and Neuroscience Research Institute, Peking University, Beijing 100083, China
- Key Laboratory for Neuroscience, Ministry of Education of China and National Committee of Health and Family Planning of China, Peking University, Beijing 100083, China
| | - Hong-Bo Jing
- Department of Neurobiology, School of Basic Medical Sciences and Neuroscience Research Institute, Peking University, Beijing 100083, China
- Key Laboratory for Neuroscience, Ministry of Education of China and National Committee of Health and Family Planning of China, Peking University, Beijing 100083, China
| | - Hong-Yan Zhao
- Department of Neurobiology, School of Basic Medical Sciences and Neuroscience Research Institute, Peking University, Beijing 100083, China
- Key Laboratory for Neuroscience, Ministry of Education of China and National Committee of Health and Family Planning of China, Peking University, Beijing 100083, China
| | - Bo-Heng Liu
- Department of Neurobiology, School of Basic Medical Sciences and Neuroscience Research Institute, Peking University, Beijing 100083, China
- Key Laboratory for Neuroscience, Ministry of Education of China and National Committee of Health and Family Planning of China, Peking University, Beijing 100083, China
| | - Ya-Jing Liang
- Department of Oral and Maxillofacial Radiology, Peking University School and Hospital of Stomatology, Beijing 100081, China
| | - Ling-Yu Liu
- Department of Neurobiology, School of Basic Medical Sciences and Neuroscience Research Institute, Peking University, Beijing 100083, China
- Key Laboratory for Neuroscience, Ministry of Education of China and National Committee of Health and Family Planning of China, Peking University, Beijing 100083, China
| | - Jie Cai
- Department of Neurobiology, School of Basic Medical Sciences and Neuroscience Research Institute, Peking University, Beijing 100083, China
- Key Laboratory for Neuroscience, Ministry of Education of China and National Committee of Health and Family Planning of China, Peking University, Beijing 100083, China
| | - You Wan
- Department of Neurobiology, School of Basic Medical Sciences and Neuroscience Research Institute, Peking University, Beijing 100083, China
- Key Laboratory for Neuroscience, Ministry of Education of China and National Committee of Health and Family Planning of China, Peking University, Beijing 100083, China
| | - Guo-Gang Xing
- Department of Neurobiology, School of Basic Medical Sciences and Neuroscience Research Institute, Peking University, Beijing 100083, China
- Key Laboratory for Neuroscience, Ministry of Education of China and National Committee of Health and Family Planning of China, Peking University, Beijing 100083, China
- Second Affiliated Hospital of Xinxiang Medical University, Henan, China
| |
Collapse
|
11
|
Giblin JP, Etayo I, Castellanos A, Andres-Bilbe A, Gasull X. Anionic Phospholipids Bind to and Modulate the Activity of Human TRESK Background K + Channel. Mol Neurobiol 2018; 56:2524-2541. [PMID: 30039335 DOI: 10.1007/s12035-018-1244-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2018] [Accepted: 07/15/2018] [Indexed: 01/08/2023]
Abstract
The background K+ channel TRESK regulates sensory neuron excitability, and changes in its function/expression contribute to neuronal hyperexcitability after injury/inflammation, making it an attractive therapeutic target for pain-related disorders. Factors that change lipid bilayer composition/properties (including volatile anesthetics, chloroform, chlorpromazine, shear stress, and cell swelling/shrinkage) modify TRESK current, but despite the importance of anionic phospholipids (e.g., PIP2) in the regulation of many ion channels, it remains unknown if membrane lipids affect TRESK function. We describe that both human and rat TRESK contain potential anionic phospholipid binding sites (apbs) in the large cytoplasmic loop, but only the human channel is able to bind to multilamellar vesicles (MLVs), enriched with anionic phospholipids, suggesting an electrostatically mediated interaction. We mapped the apbs to a short stretch of 14 amino acids in the loop, located at the membrane-cytosol interface. Disruption of electrostatic lipid-TRESK interactions inhibited hTRESK currents, while subsequent application of Folch Fraction MLVs or a PIP2 analog activated hTRESK, an effect that was absent in the rat ortholog. Strikingly, channel activation by anionic phospholipids was conferred to rTRESK by replacing the equivalent rat sequence with the human apbs. Finally, in the presence of a calcineurin inhibitor, stimulation of a Gq/11-linked GPCR reduced hTRESK current, revealing a likely inhibitory effect of membrane lipid hydrolysis on hTRESK activity. This novel regulation of hTRESK by anionic phospholipids is a characteristic of the human channel that is not present in rodent orthologs. This must be considered when extrapolating results from animal models and may open the door to the development of novel channel modulators as analgesics.
Collapse
Affiliation(s)
- Jonathan P Giblin
- Neurophysiology Lab, Department of Biomedicine, Medical School, Institute of Neurosciences, Universitat de Barcelona, Casanova 143, 08036, Barcelona, Spain
- Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), 08036, Barcelona, Spain
| | - Iñigo Etayo
- Neurophysiology Lab, Department of Biomedicine, Medical School, Institute of Neurosciences, Universitat de Barcelona, Casanova 143, 08036, Barcelona, Spain
| | - Aida Castellanos
- Neurophysiology Lab, Department of Biomedicine, Medical School, Institute of Neurosciences, Universitat de Barcelona, Casanova 143, 08036, Barcelona, Spain
- Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), 08036, Barcelona, Spain
| | - Alba Andres-Bilbe
- Neurophysiology Lab, Department of Biomedicine, Medical School, Institute of Neurosciences, Universitat de Barcelona, Casanova 143, 08036, Barcelona, Spain
- Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), 08036, Barcelona, Spain
| | - Xavier Gasull
- Neurophysiology Lab, Department of Biomedicine, Medical School, Institute of Neurosciences, Universitat de Barcelona, Casanova 143, 08036, Barcelona, Spain.
- Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), 08036, Barcelona, Spain.
| |
Collapse
|
12
|
Verapamil Inhibits TRESK (K 2P18.1) Current in Trigeminal Ganglion Neurons Independently of the Blockade of Ca 2+ Influx. Int J Mol Sci 2018; 19:ijms19071961. [PMID: 29973548 PMCID: PMC6073232 DOI: 10.3390/ijms19071961] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Revised: 06/27/2018] [Accepted: 07/02/2018] [Indexed: 12/29/2022] Open
Abstract
Tandem pore domain weak inward rectifier potassium channel (TWIK)-related spinal cord K⁺ (TRESK; K2P18.1) channel is the only member of the two-pore domain K⁺ (K2P) channel family that is activated by an increase in intracellular Ca2+ concentration ([Ca2+]i) and linked to migraines. This study was performed to identify the effect of verapamil, which is an L-type Ca2+ channel blocker and a prophylaxis for migraines, on the TRESK channel in trigeminal ganglion (TG) neurons, as well as in a heterologous system. Single-channel and whole-cell currents were recorded in TG neurons and HEK-293 cells transfected with mTRESK using patch-clamping techniques. In TG neurons, changes in [Ca2+]i were measured using the fluo-3-AM Ca2+ indicator. Verapamil, nifedipine, and NiCl₂ inhibited the whole-cell currents in HEK-293 cells overexpressing mTRESK with IC50 values of 5.2, 54.3, and >100 μM, respectively. The inhibitory effect of verapamil on TRESK channel was also observed in excised patches. In TG neurons, verapamil (10 μM) inhibited TRESK channel activity by approximately 76%. The TRESK channel activity was not dependent on the presence of extracellular Ca2+. In addition, the inhibitory effect of verapamil on the TRESK channel remained despite the absence of extracellular Ca2+. These findings show that verapamil inhibits the TRESK current independently of the blockade of Ca2+ influx in TG neurons. Verapamil will be able to exert its pharmacological effects by modulating TRESK, as well as Ca2+ influx, in TG neurons in vitro. We suggest that verapamil could be used as an inhibitor for identifying TRESK channel in TG neurons.
Collapse
|
13
|
Lee SH, Kang D, Ok SH, Kwon SC, Kim HJ, Kim EJ, Hong JM, Kim JY, Bae SI, An S, Sohn JT. Linoleic Acid Attenuates the Toxic Dose of Bupivacaine-Mediated Reduction of Vasodilation Evoked by the Activation of Adenosine Triphosphate-Sensitive Potassium Channels. Int J Mol Sci 2018; 19:ijms19071876. [PMID: 29949899 PMCID: PMC6073907 DOI: 10.3390/ijms19071876] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Revised: 06/19/2018] [Accepted: 06/22/2018] [Indexed: 01/20/2023] Open
Abstract
The goal of this study was to investigate the effect of lipid emulsion on a toxic dose of local anesthetic-mediated reduction of vasodilation evoked by the ATP-sensitive potassium (KATP) channel agonist levcromakalim. The effect of lipid emulsion (LE) and linoleic acid on the local anesthetic-mediated reduction of vasodilation and membrane hyperpolarization evoked by levcromakalim was assessed in isolated endothelium-denuded vessels (rat aorta and mesenteric artery) and aortic vascular smooth muscle cells. The effect of LE and linoleic acid on KATP channel activity in transfected HEK-293 cells was investigated, as was the effect of LE on bupivacaine concentration. The efficacy of LE in attenuating the local anesthetic-mediated reduction of vasodilation evoked by levcromakalim was correlated with the lipid solubility of the local anesthetic. Linoleic acid attenuated the bupivacaine-mediated reduction of vasodilation evoked by levcromakalim. LE decreased the bupivacaine-mediated reduction of membrane hyperpolarization evoked by levcromakalim but did not significantly alter the mepivacaine-mediated reduction. LE and linoleic acid both reversed the bupivacaine-mediated decrease of KATP activity and enhanced KATP activity. LE decreased the bupivacaine concentration. Linoleic acid may be the major contributor to LE-induced attenuation of bupivacaine-mediated reduction of vasodilation evoked by levcromakalim via the direct activation of KATP channels and indirect effects.
Collapse
Affiliation(s)
- Soo Hee Lee
- Department of Anesthesiology and Pain Medicine, Gyeongsang National University School of Medicine, Gyeongsang National University Hospital, 15 Jinju-daero 816 beon-gil, Jinju-si 52727, Republic of Korea.
- Institute of Health Sciences, Gyeongsang National University, Jinju-si 52727, Republic of Korea.
| | - Dawon Kang
- Department of Physiology, Gyeongsang National University School of Medicine, Jinju-si 52727, Republic of Korea.
| | - Seong-Ho Ok
- Department of Anesthesiology and Pain Medicine, Gyeongsang National University School of Medicine, Gyeongsang National University Hospital, 15 Jinju-daero 816 beon-gil, Jinju-si 52727, Republic of Korea.
- Institute of Health Sciences, Gyeongsang National University, Jinju-si 52727, Republic of Korea.
| | - Seong-Chun Kwon
- Department of Physiology, Institute of Clinical and Translational Research, Catholic Kwangdong University, College of Medicine, Gangneung 25601, Republic of Korea.
| | - Hyun-Jin Kim
- Division of Applied Life Sciences (BK21 plus), Gyeongsang National University, 501 Jinju-daero, Jinju 52828, Republic of Korea.
- Department of Food Science & Technology, and Institute of Agriculture and Life Science, Gyeongsang National University, 501 Jinju-daero, Jinju 52828, Republic of Korea.
| | - Eun-Jin Kim
- Department of Physiology, Gyeongsang National University School of Medicine, Jinju-si 52727, Republic of Korea.
| | - Jeong-Min Hong
- Department of Anesthesia and Pain Medicine, Pusan National University Hospital, Biomed Research Institute, Pusan National University School of Medicine, Busan 49241, Republic of Korea.
| | - Ji-Yoon Kim
- Department of Anesthesiology and Pain Medicine, Gyeongsang National University Hospital, 15 Jinju-daero 816 beon-gil, Jinju-si 52727, Republic of Korea.
| | - Sung Il Bae
- Department of Anesthesiology and Pain Medicine, Gyeongsang National University Hospital, 15 Jinju-daero 816 beon-gil, Jinju-si 52727, Republic of Korea.
| | - Seungmin An
- Department of Anesthesiology and Pain Medicine, Gyeongsang National University Hospital, 15 Jinju-daero 816 beon-gil, Jinju-si 52727, Republic of Korea.
| | - Ju-Tae Sohn
- Department of Anesthesiology and Pain Medicine, Gyeongsang National University School of Medicine, Gyeongsang National University Hospital, 15 Jinju-daero 816 beon-gil, Jinju-si 52727, Republic of Korea.
- Institute of Health Sciences, Gyeongsang National University, Jinju-si 52727, Republic of Korea.
| |
Collapse
|
14
|
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.
Collapse
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)
| |
Collapse
|
15
|
Lengyel M, Dobolyi A, Czirják G, Enyedi P. Selective and state-dependent activation of TRESK (K 2P 18.1) background potassium channel by cloxyquin. Br J Pharmacol 2017; 174:2102-2113. [PMID: 28419410 DOI: 10.1111/bph.13821] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2016] [Revised: 04/03/2017] [Accepted: 04/03/2017] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND AND PURPOSE Cloxyquin (5-cloroquinolin-8-ol) has been described as an activator of TRESK (K2P 18.1, TWIK-related spinal cord K+ channel) background potassium channel. We have examined the specificity of the drug by testing several K2P channels. We have investigated the mechanism of cloxyquin-mediated TRESK activation, focusing on the differences between the physiologically relevant regulatory states of the channel. EXPERIMENTAL APPROACH Potassium currents were measured by two-electrode voltage clamp in Xenopus oocytes and by whole-cell patch clamp in mouse dorsal root ganglion (DRG) neurons. KEY RESULTS Cloxyquin (100 µM) activated mouse and human TRESK 4.4 ± 0.3 (n = 28) and 3.9 ± 0.3-fold (n = 8), respectively. The drug selectively targeted TRESK in the K2P channel family and exerted state-dependent effects. TRESK was potently activated by cloxyquin in the resting state. However, after robust activation of the current by the calcium signal, evoked by stimulation of Gq-coupled receptors, the compound did not influence mouse TRESK and only slightly affected the human channel. The constitutively active mutant channels, mimicking the dephosphorylated state (S276A) or containing altered channel pore (F156A and F364A), were not further stimulated by cloxyquin. In a subpopulation of isolated DRG neurons, cloxyquin substantially activated the background potassium current. CONCLUSIONS AND IMPLICATIONS Cloxyquin activates TRESK by a Ca2+ /calcineurin-independent mechanism. The drug is specific for TRESK within the K2P channel family and useful for studying TRESK currents in native cells. The state-dependent pharmacological profile of this channel should be considered in the development of therapeutics for migraine and other nociceptive disorders.
Collapse
Affiliation(s)
- Miklós Lengyel
- Department of Physiology, Semmelweis University, Budapest, Hungary
| | - Alice Dobolyi
- Department of Physiology, Semmelweis University, Budapest, Hungary
| | - Gábor Czirják
- Department of Physiology, Semmelweis University, Budapest, Hungary
| | - Péter Enyedi
- Department of Physiology, Semmelweis University, Budapest, Hungary
| |
Collapse
|
16
|
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 DOI: 10.1021/acschemneuro.6b00301] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [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.
Collapse
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
| |
Collapse
|
17
|
Park H, Kim EJ, Han J, Han J, Kang D. Effects of analgesics and antidepressants on TREK-2 and TRESK currents. THE KOREAN JOURNAL OF PHYSIOLOGY & PHARMACOLOGY : OFFICIAL JOURNAL OF THE KOREAN PHYSIOLOGICAL SOCIETY AND THE KOREAN SOCIETY OF PHARMACOLOGY 2016; 20:379-85. [PMID: 27382354 PMCID: PMC4930906 DOI: 10.4196/kjpp.2016.20.4.379] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/04/2016] [Revised: 05/04/2016] [Accepted: 05/09/2016] [Indexed: 01/18/2023]
Abstract
TWIK-related K+ channel-2 (TREK-2) and TWIK-related spinal cord K+ (TRESK) channel are members of two-pore domain K+ channel family. They are well expressed and help to set the resting membrane potential in sensory neurons. Modulation of TREK-2 and TRESK channels are involved in the pathogenesis of pain, and specifi c activators of TREK-2 and TRESK may be benefi cial for the treatment of pain symptoms. However, the effect of commonly used analgesics on TREK-2 and TRESK channels are not known. Here, we investigated the effect of analgesics on TREK-2 and TRESK channels. The effects of analgesics were examined in HEK cells transfected with TREK-2 or TRESK. Amitriptyline, citalopram, escitalopram, and fluoxetine significantly inhibited TREK-2 and TRESK currents in HEK cells (p<0.05, n=10). Acetaminophen, ibuprofen, nabumetone, and bupropion inhibited TRESK, but had no effect on TREK-2. These results show that all analgesics tested in this study inhibit TRESK activity. Further study is needed to identify the mechanisms by which the analgesics modulate TREK-2 and TRESK differently.
Collapse
Affiliation(s)
- Hyun Park
- Department of Neurosurgery, Gyeongsang National University Hospital, College of Medicine and Institute of Health Sciences, Gyeongsang National University, Jinju 52727, Korea
| | - Eun-Jin Kim
- Department of Physiology, College of Medicine and Institute of Health Sciences, Gyeongsang National University, Jinju 52727, Korea
| | - Jaehee Han
- Department of Physiology, College of Medicine and Institute of Health Sciences, Gyeongsang National University, Jinju 52727, Korea
| | - Jongwoo Han
- Department of Neurosurgery, Gyeongsang National University Hospital, College of Medicine and Institute of Health Sciences, Gyeongsang National University, Jinju 52727, Korea
| | - Dawon Kang
- Department of Physiology, College of Medicine and Institute of Health Sciences, Gyeongsang National University, Jinju 52727, Korea
| |
Collapse
|
18
|
Rainero I, Rubino E, Gallone S, Zavarise P, Carli D, Boschi S, Fenoglio P, Savi L, Gentile S, Benna P, Pinessi L, Dalla Volta G. KCNK18 (TRESK) genetic variants in Italian patients with migraine. Headache 2015; 54:1515-22. [PMID: 25324165 DOI: 10.1111/head.12439] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/18/2014] [Indexed: 11/27/2022]
Abstract
OBJECTIVES To evaluate the prevalence of KCNK18 gene mutations in a dataset of Italian migraineurs, with and without aura, and in healthy controls, and to investigate in silico the functional effects of the mutations. BACKGROUND A role for the KCNK18 gene encoding for TRESK, a member of the family of potassium channel, has been recently suggested in migraine with aura. METHODS We sequenced the KCNK18 gene in 425 migraineurs (255 with aura and 170 without aura) and 247 healthy controls. RESULTS Five genetic variants (R10G, C110R, Y163Y, S231P, and F372L) were found in 13 (5.1%) out of 255 migraine with aura patients, and 6 variants (R10G, D46D, C110R, Y163Y, S178T, and S231P) were identified in 12 (7.1%) out of 170 migraine without aura patients. In 2.8% of controls, the R10G and L20V substitutions were found. In silico analysis suggested that C110R, S178T, S231P, and F372L mutations may have potential damaging effect on channel function, whereas the remaining mutations may have low damaging effect. CONCLUSIONS Our study shows the presence of several KCNK18 gene mutations in both migraine with aura and migraine without aura. However, the precise role of this gene in migraine predisposition deserves further studies.
Collapse
Affiliation(s)
- Innocenzo Rainero
- Neurology I - Headache Center, Department of Neuroscience "Rita Levi Montalcini, University of Torino, Torino, Italy
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
19
|
Kollert S, Dombert B, Döring F, Wischmeyer E. Activation of TRESK channels by the inflammatory mediator lysophosphatidic acid balances nociceptive signalling. Sci Rep 2015. [PMID: 26224542 PMCID: PMC4519772 DOI: 10.1038/srep12548] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
In dorsal root ganglia (DRG) neurons TRESK channels constitute a major current component of the standing outward current IKSO. A prominent physiological role of TRESK has been attributed to pain sensation. During inflammation mediators of pain e.g. lysophosphatidic acid (LPA) are released and modulate nociception. We demonstrate co-expression of TRESK and LPA receptors in DRG neurons. Heterologous expression of TRESK and LPA receptors in Xenopus oocytes revealed augmentation of basal K+ currents upon LPA application. In DRG neurons nociception can result from TRPV1 activation by capsaicin or LPA. Upon co-expression in Xenopus oocytes LPA simultaneously increased both depolarising TRPV1 and hyperpolarising TRESK currents. Patch-clamp recordings in cultured DRG neurons from TRESK[wt] mice displayed increased IKSO after application of LPA whereas under these conditions IKSO in neurons from TRESK[ko] mice remained unaltered. Under current-clamp conditions LPA application differentially modulated excitability in these genotypes upon depolarising pulses. Spike frequency was attenuated in TRESK[wt] neurons and, in contrast, augmented in TRESK[ko] neurons. Accordingly, excitation of nociceptive neurons by LPA is balanced by co-activation of TRESK channels. Hence excitation of sensory neurons is strongly controlled by the activity of TRESK channels, which therefore are good candidates for the treatment of pain disorders.
Collapse
Affiliation(s)
- Sina Kollert
- Institute of Physiology, AG Molecular Electrophysiology, University of Würzburg, 97070 Würzburg Germany
| | - Benjamin Dombert
- Institute for Clinical Neurobiology, University Hospital Würzburg, 97078 Würzburg, Germany
| | - Frank Döring
- Institute of Physiology, AG Molecular Electrophysiology, University of Würzburg, 97070 Würzburg Germany
| | - Erhard Wischmeyer
- Institute of Physiology, AG Molecular Electrophysiology, University of Würzburg, 97070 Würzburg Germany
| |
Collapse
|
20
|
Enyedi P, Czirják G. Properties, regulation, pharmacology, and functions of the K₂p channel, TRESK. Pflugers Arch 2014; 467:945-58. [PMID: 25366493 DOI: 10.1007/s00424-014-1634-8] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2014] [Revised: 10/09/2014] [Accepted: 10/12/2014] [Indexed: 12/21/2022]
Abstract
TWIK-related spinal cord K(+) channel (TRESK) is the gene product of KCNK18, the last discovered leak potassium K2P channel gene. Under resting conditions, TRESK is constitutively phosphorylated at two regulatory regions. Protein kinase A (PKA) and microtubule affinity-regulating (MARK) kinases can be applied in experiments to phosphorylate these sites of TRESK expressed in Xenopus oocytes, respectively. Upon generation of a calcium signal, TRESK is dephosphorylated and thereby activated by calcineurin. In this process, the binding of calcineurin to the channel by non-catalytic interacting sites is essential. The phosphorylation/dephosphorylation regulatory process is modified by 14-3-3 proteins. Human, but not murine TRESK is also activated by protein kinase C. TRESK is expressed most abundantly in sensory neurons of the dorsal root ganglia (DRG) and trigeminal ganglia, and the channel modifies certain forms of nociceptive afferentation. In a large pedigree, a dominant negative mutant TRESK allele was found to co-segregate perfectly with migraine phenotype. While this genetic defect may be responsible only for a very small fraction of migraine cases, specific TRESK activation is expected to exert beneficial effect in common forms of the disease.
Collapse
Affiliation(s)
- Péter Enyedi
- Department of Physiology, Semmelweis University, P.O. Box 259, 1444, Budapest, Hungary,
| | | |
Collapse
|
21
|
Czirják G, Enyedi P. The LQLP calcineurin docking site is a major determinant of the calcium-dependent activation of human TRESK background K+ channel. J Biol Chem 2014; 289:29506-18. [PMID: 25202008 DOI: 10.1074/jbc.m114.577684] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Calcium-dependent activation of human TRESK (TWIK-related spinal cord K(+) channel, K2P18.1) depends on direct targeting of calcineurin to the PQIIIS motif. In the present study we demonstrate that TRESK also contains another functionally relevant docking site for the phosphatase, the LQLP amino acid sequence. Combined mutations of the PQIIIS and LQLP motifs were required to eliminate the calcium-dependent regulation of the channel. In contrast to the alanine substitutions of PQIIIS, the mutation of LQLP to AQAP alone did not significantly change the amplitude of TRESK activation evoked by the substantial elevation of cytoplasmic calcium concentration. However, the AQAP mutation slowed down the response to high calcium. In addition, modest elevation of [Ca(2+)], which effectively regulated the wild type channel, failed to activate TRESK-AQAP. This indicates that the AQAP mutation diminished the sensitivity of TRESK to calcium. Even if PQIIIS was replaced by the PVIVIT sequence of high calcineurin binding affinity, the effect of the AQAP mutation was clearly detected in this TRESK-PVIVIT context. Substitution of the LQLP region with the corresponding fragment of NFAT transcription factor, perfectly matching the previously described LXVP calcineurin-binding consensus sequence, increased the calcium-sensitivity of TRESK-PVIVIT. Thus the enhancement of the affinity of TRESK for calcineurin by the incorporation of PVIVIT could not compensate for or prevent the effects of LQLP sequence modifications, suggesting that the two calcineurin-binding regions play distinct roles in the regulation. Our results indicate that the LQLP site is a fundamental determinant of the calcium-sensitivity of human TRESK.
Collapse
Affiliation(s)
- Gábor Czirják
- From the Department of Physiology, Semmelweis University, Budapest, Hungary
| | - Péter Enyedi
- From the Department of Physiology, Semmelweis University, Budapest, Hungary
| |
Collapse
|
22
|
Du X, Hao H, Gigout S, Huang D, Yang Y, Li L, Wang C, Sundt D, Jaffe DB, Zhang H, Gamper N. Control of somatic membrane potential in nociceptive neurons and its implications for peripheral nociceptive transmission. Pain 2014; 155:2306-22. [PMID: 25168672 PMCID: PMC4247381 DOI: 10.1016/j.pain.2014.08.025] [Citation(s) in RCA: 87] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2014] [Revised: 08/02/2014] [Accepted: 08/19/2014] [Indexed: 01/10/2023]
Abstract
Peripheral sensory ganglia contain somata of afferent fibres conveying somatosensory inputs to the central nervous system. Growing evidence suggests that the somatic/perisomatic region of sensory neurons can influence peripheral sensory transmission. Control of resting membrane potential (Erest) is an important mechanism regulating excitability, but surprisingly little is known about how Erest is regulated in sensory neuron somata or how changes in somatic/perisomatic Erest affect peripheral sensory transmission. We first evaluated the influence of several major ion channels on Erest in cultured small-diameter, mostly capsaicin-sensitive (presumed nociceptive) dorsal root ganglion (DRG) neurons. The strongest and most prevalent effect on Erest was achieved by modulating M channels, K2P and 4-aminopiridine-sensitive KV channels, while hyperpolarization-activated cyclic nucleotide-gated, voltage-gated Na+, and T-type Ca2+ channels to a lesser extent also contributed to Erest. Second, we investigated how varying somatic/perisomatic membrane potential, by manipulating ion channels of sensory neurons within the DRG, affected peripheral nociceptive transmission in vivo. Acute focal application of M or KATP channel enhancers or a hyperpolarization-activated cyclic nucleotide-gated channel blocker to L5 DRG in vivo significantly alleviated pain induced by hind paw injection of bradykinin. Finally, we show with computational modelling how somatic/perisomatic hyperpolarization, in concert with the low-pass filtering properties of the t-junction within the DRG, can interfere with action potential propagation. Our study deciphers a complement of ion channels that sets the somatic Erest of nociceptive neurons and provides strong evidence for a robust filtering role of the somatic and perisomatic compartments of peripheral nociceptive neuron.
Collapse
Affiliation(s)
- Xiaona Du
- Department of Pharmacology, Hebei Medical University, Shijiazhuang, PR China.
| | - Han Hao
- Department of Pharmacology, Hebei Medical University, Shijiazhuang, PR China
| | - Sylvain Gigout
- Faculty of Biological Sciences, School of Biomedical Sciences, University of Leeds, Leeds, UK
| | - Dongyang Huang
- Department of Pharmacology, Hebei Medical University, Shijiazhuang, PR China
| | - Yuehui Yang
- Department of Pharmacology, Hebei Medical University, Shijiazhuang, PR China
| | - Li Li
- Department of Pharmacology, Hebei Medical University, Shijiazhuang, PR China
| | - Caixue Wang
- Department of Pharmacology, Hebei Medical University, Shijiazhuang, PR China
| | - Danielle Sundt
- Department of Biology, University of Texas at San Antonio, San Antonio, TX, USA
| | - David B Jaffe
- Department of Biology, University of Texas at San Antonio, San Antonio, TX, USA
| | - Hailin Zhang
- Department of Pharmacology, Hebei Medical University, Shijiazhuang, PR China
| | - Nikita Gamper
- Department of Pharmacology, Hebei Medical University, Shijiazhuang, PR China; Faculty of Biological Sciences, School of Biomedical Sciences, University of Leeds, Leeds, UK.
| |
Collapse
|
23
|
Bruner JK, Zou B, Zhang H, Zhang Y, Schmidt K, Li M. Identification of novel small molecule modulators of K2P18.1 two-pore potassium channel. Eur J Pharmacol 2014; 740:603-10. [PMID: 24972239 DOI: 10.1016/j.ejphar.2014.06.021] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2014] [Revised: 06/11/2014] [Accepted: 06/17/2014] [Indexed: 11/19/2022]
Abstract
Two-pore domain potassium (K2P) channels are responsible for background potassium (K+) current, which is crucial for the maintenance of resting membrane potential. K2P18.1, also called TWIK-related spinal cord K+ channel (TRESK) or KCNK18, is thought to be a major contributor to background K+ currents, particularly in sensory neurons where it is abundantly expressed. Despite its critical role and potential therapeutic implication, pharmacological tools for probing K2P18.1 activity remain unavailable. Here, we report a high-throughput screen against a collection of bioactive compounds that yielded 26 inhibitors and 8 activators of K2P18.1 channel activity with more than 10-fold selectivity over the homologous channel K2P9.1. Among these modulators, the antihistamine loratadine inhibited K2P18.1 activity with IC50 of 0.49±0.23 µM and is considerably more potent than existing K2P18.1 inhibitors. Importantly, the inhibition by loratadine remains equally efficacious upon potentiation of K2P18.1 by calcium signaling. Furthermore, the loratadine effect is dependent on transmembrane residues F145 and F352, providing orthogonal evidence that the inhibition is caused by a direct compound-channel interaction. This study reveals new pharmacological modulators of K2P18.1 activity useful in dissecting native K2P18.1 function.
Collapse
Affiliation(s)
- J Kyle Bruner
- The Solomon H. Snyder Department of Neuroscience, High Throughput Biology Center, Johns Hopkins University, Baltimore, MD 21205, USA; Johns Hopkins Ion Channel Center (JHICC), Johns Hopkins University, Baltimore, MD 21205, USA
| | - Beiyan Zou
- The Solomon H. Snyder Department of Neuroscience, High Throughput Biology Center, Johns Hopkins University, Baltimore, MD 21205, USA; Johns Hopkins Ion Channel Center (JHICC), Johns Hopkins University, Baltimore, MD 21205, USA
| | - Hongkang Zhang
- The Solomon H. Snyder Department of Neuroscience, High Throughput Biology Center, Johns Hopkins University, Baltimore, MD 21205, USA; Johns Hopkins Ion Channel Center (JHICC), Johns Hopkins University, Baltimore, MD 21205, USA
| | - Yixin Zhang
- The Solomon H. Snyder Department of Neuroscience, High Throughput Biology Center, Johns Hopkins University, Baltimore, MD 21205, USA; Johns Hopkins Ion Channel Center (JHICC), Johns Hopkins University, Baltimore, MD 21205, USA
| | - Katharina Schmidt
- Department of Physiology, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Min Li
- The Solomon H. Snyder Department of Neuroscience, High Throughput Biology Center, Johns Hopkins University, Baltimore, MD 21205, USA; Johns Hopkins Ion Channel Center (JHICC), Johns Hopkins University, Baltimore, MD 21205, USA.
| |
Collapse
|
24
|
Guo Z, Liu P, Ren F, Cao YQ. Nonmigraine-associated TRESK K+ channel variant C110R does not increase the excitability of trigeminal ganglion neurons. J Neurophysiol 2014; 112:568-79. [PMID: 24805079 DOI: 10.1152/jn.00267.2014] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Recent genetic studies suggest that dysfunction of ion channels and transporters may contribute to migraine pathophysiology. A migraine-associated frameshift mutation in the TWIK-related spinal cord K+ (TRESK) channel results in nonfunctional channels. Moreover, mutant TRESK subunits exert a dominant-negative effect on whole cell TRESK currents and result in hyperexcitability of small-diameter trigeminal ganglion (TG) neurons, suggesting that mutant TRESK may increase the gain of the neuronal circuit underlying migraine headache. However, the nonmigraine-associated TRESK C110R variant exhibits the same effect on TRESK currents as the mutant subunits in Xenopus oocytes, suggesting that dysfunction of TRESK is not sufficient to cause migraine. Here, we confirmed that the C110R variant formed nonfunctional channels and exerted a dominant-negative effect on TRESK currents in HEK293T cells, similar to the migraine-associated mutant TRESK. To compare the functional consequences of TRESK mutations/variants in a more physiological setting, we expressed the mutant TRESK and the C110R variant in cultured mouse TG neurons and investigated their effects on background K+ currents and neuronal excitability. Both mutant TRESK and the C110R variant reduced the endogenous TRESK currents in TG neurons, but the effect of the C110R variant was significantly smaller. Importantly, only TG neurons expressing mutant TRESK subunits, but not those expressing the C110R variant, exhibited a significant increase in excitability. Thus only the migraine-associated TRESK mutation, but not the C110R variant, reduces the endogenous TRESK currents to a degree that affects TG excitability. Our results support a potential causal relationship between the frameshift TRESK mutation and migraine susceptibility.
Collapse
Affiliation(s)
- Zhaohua Guo
- Washington University Pain Center and Department of Anesthesiology, Washington University School of Medicine, St. Louis, Missouri
| | - Ping Liu
- Washington University Pain Center and Department of Anesthesiology, Washington University School of Medicine, St. Louis, Missouri
| | - Fei Ren
- Washington University Pain Center and Department of Anesthesiology, Washington University School of Medicine, St. Louis, Missouri
| | - Yu-Qing Cao
- Washington University Pain Center and Department of Anesthesiology, Washington University School of Medicine, St. Louis, Missouri
| |
Collapse
|
25
|
Guo Z, Cao YQ. Over-expression of TRESK K(+) channels reduces the excitability of trigeminal ganglion nociceptors. PLoS One 2014; 9:e87029. [PMID: 24466320 PMCID: PMC3900698 DOI: 10.1371/journal.pone.0087029] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2013] [Accepted: 12/20/2013] [Indexed: 01/17/2023] Open
Abstract
TWIK-related spinal cord K+ (TRESK) channel is abundantly expressed in trigeminal ganglion (TG) and dorsal root ganglion neurons and is one of the major background K+ channels in primary afferent neurons. Mutations in TRESK channels are associated with familial and sporadic migraine. In rats, both chronic nerve injury and inflammation alter the expression level of TRESK mRNA. Functional studies indicate that reduction of endogenous TRESK channel activity results in hyper-excitation of primary afferent neurons, suggesting that TRESK is a potential target for the development of new analgesics. However, whether and how enhancing TRESK channel activity would decrease the excitability of primary afferent neurons has not been directly tested. Here, we over-expressed TRESK subunits in cultured mouse TG neurons by lipofectamine-mediated transfection and investigated how this altered the membrane properties and the excitability of the small-diameter TG population. To account for the heterogeneity of neurons, we further divided small TG neurons into two groups, based on their ability to bind to fluorescently-labeled isolectin B (IB4). The transfected TG neurons showed a 2-fold increase in the level of TRESK proteins. This was accompanied by a significant increase in the fraction of lamotrigine-sensitive persistent K+ currents as well as the size of total background K+ currents. Consequently, both IB4-positive and IB4-negative TG neurons over-expressing TRESK subunits exhibited a lower input resistance and a 2-fold increase in the current threshold for action potential initiation. IB4-negative TG neurons over-expressing TRESK subunits also showed a significant reduction of the spike frequency in response to supra-threshold stimuli. Importantly, an increase in TRESK channel activity effectively inhibited capsaicin-evoked spikes in TG neurons. Taken together, our results suggest that potent and specific TRESK channel openers likely would reduce the excitability of primary afferent neurons and therefore are potential therapeutics for the treatment of migraine and other chronic pain symptoms.
Collapse
Affiliation(s)
- Zhaohua Guo
- Washington University Pain Center and Department of Anesthesiology, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Yu-Qing Cao
- Washington University Pain Center and Department of Anesthesiology, Washington University School of Medicine, St. Louis, Missouri, United States of America
| |
Collapse
|
26
|
Liu P, Xiao Z, Ren F, Guo Z, Chen Z, Zhao H, Cao YQ. Functional analysis of a migraine-associated TRESK K+ channel mutation. J Neurosci 2013; 33:12810-24. [PMID: 23904616 PMCID: PMC3728689 DOI: 10.1523/jneurosci.1237-13.2013] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2013] [Revised: 06/28/2013] [Accepted: 06/28/2013] [Indexed: 11/21/2022] Open
Abstract
Recent genetic and functional studies suggest that migraine may result from abnormal activities of ion channels and transporters. A frameshift mutation in the human TWIK-related spinal cord K(+) (TRESK) channel has been identified in migraine with aura patients in a large pedigree. In Xenopus oocytes, mutant TRESK subunits exert a dominant-negative effect on whole-cell TRESK currents. However, questions remain as to whether and how mutant TRESK subunits affect the membrane properties and the excitability of neurons in the migraine circuit. Here, we investigated the functional consequences of the mutant TRESK subunits in HEK293T cells and mouse trigeminal ganglion (TG) neurons. First, we found that mutant TRESK subunits exhibited dominant-negative effects not only on the size of the whole-cell TRESK currents, but also on the level of TRESK channels on the plasma membrane in HEK293T cells. This likely resulted from the heterodimerization of wild-type and mutant TRESK subunits. Next, we expressed mutant TRESK subunits in cultured TG neurons and observed a significant decrease in the lamotrigine-sensitive K(+) current, suggesting that the mutant TRESK subunits have a dominant-negative effect on currents through the endogenous TRESK channels. Current-clamp recordings showed that neurons expressing mutant TRESK subunits had a higher input resistance, a lower current threshold for action potential initiation, and a higher spike frequency in response to suprathreshold stimuli, indicating that the mutation resulted in hyperexcitability of TG neurons. Our results suggest a possible mechanism through which the TRESK mutation increases the susceptibility of migraine headache.
Collapse
Affiliation(s)
- Ping Liu
- Washington University Pain Center and
- Department of Anesthesiology, Washington University School of Medicine, St. Louis, Missouri 63110
| | - Zheman Xiao
- Washington University Pain Center and
- Department of Anesthesiology, Washington University School of Medicine, St. Louis, Missouri 63110
| | - Fei Ren
- Washington University Pain Center and
- Department of Anesthesiology, Washington University School of Medicine, St. Louis, Missouri 63110
| | - Zhaohua Guo
- Washington University Pain Center and
- Department of Anesthesiology, Washington University School of Medicine, St. Louis, Missouri 63110
| | - Ziwei Chen
- Department of Anesthesiology, Washington University School of Medicine, St. Louis, Missouri 63110
| | - Hucheng Zhao
- Washington University Pain Center and
- Department of Anesthesiology, Washington University School of Medicine, St. Louis, Missouri 63110
| | - Yu-Qing Cao
- Washington University Pain Center and
- Department of Anesthesiology, Washington University School of Medicine, St. Louis, Missouri 63110
| |
Collapse
|
27
|
Callejo G, Giblin JP, Gasull X. Modulation of TRESK background K+ channel by membrane stretch. PLoS One 2013; 8:e64471. [PMID: 23691227 PMCID: PMC3655163 DOI: 10.1371/journal.pone.0064471] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2013] [Accepted: 04/15/2013] [Indexed: 12/03/2022] Open
Abstract
The two-pore domain K+ channel TRESK is expressed in dorsal root ganglion and trigeminal sensory neurons where it is a major contributor to background K+ current. TRESK acts as a break to prevent excessive sensory neuron activation and decreases in its expression or function have been involved in neuronal hyperexcitability after injury/inflammation, migraine or altered sensory perception (tingling, cooling and pungent burning sensations). All these effects have implicated this channel in nociception and mechanotransduction. To determine the role of TRESK in sensory transduction, we studied its sensitivity to changes in membrane tension (stretch) in heterologous systems, F-11 cells and trigeminal neurons. Laminar shear stress increased TRESK currents by 22–30%. An increase in membrane tension induced by cell swelling (hypotonic medium) produced a reversible elevation of TRESK currents (39.9%). In contrast, cell shrinkage (hypertonic solution) produced the opposite effect. Membrane crenators or cup-formers produced equivalent effects. In trigeminal sensory neurons, TRESK channels were mechanically stimulated by negative pressure, which led to a 1.51-fold increase in channel open probability. TRESK-like currents in trigeminal neurons were additively inhibited by arachidonic acid, acidic pH and hypertonic stimulation, conditions usually found after tissue inflammation. Our results show that TRESK is modulated by changes in cell membrane tension and/or cell volume. Several key players released during inflammation or tissue injury could modulate sensory neuron activation through small changes in membrane tension.
Collapse
Affiliation(s)
- Gerard Callejo
- Neurophysiology Lab, Deptartment of Physiological Sciences I, Medical School, Universitat de Barcelona, Barcelona, Spain
- Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
| | - Jonathan P. Giblin
- Neurophysiology Lab, Deptartment of Physiological Sciences I, Medical School, Universitat de Barcelona, Barcelona, Spain
- Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
| | - Xavier Gasull
- Neurophysiology Lab, Deptartment of Physiological Sciences I, Medical School, Universitat de Barcelona, Barcelona, Spain
- Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
- * E-mail:
| |
Collapse
|
28
|
Lee ES, Ryu JH, Kim EJ, Kim GT, Cho YW, Park HJ, Tak HM, Han J, Kang D. Lamotrigine increases intracellular Ca(2+) levels and Ca(2+)/calmodulin-dependent kinase II activation in mouse dorsal root ganglion neurones. Acta Physiol (Oxf) 2013; 207:397-404. [PMID: 23227957 DOI: 10.1111/apha.12034] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2012] [Revised: 09/29/2012] [Accepted: 10/29/2012] [Indexed: 01/08/2023]
Abstract
AIM Lamotrigine is a neuroprotective agent that is used clinically for the treatment of seizures and neuropathic pain. A significant volume of literature has reported that lamotrigine exerts analgesic effect by blocking Ca(2+) channels. However, little is known regarding the effect of lamotrigine on the intracellular Ca(2+) concentration ([Ca(2+)](i)). The aim of this study was to determine whether lamotrigine modulates [Ca(2+)](i) in sensory neurones. METHODS Lamotrigine-induced changes in [Ca(2+)](i) were measured in mouse dorsal root ganglion (DRG) neurones using the Ca(2+)-sensitive fluorescent indicator Fluo 3-AM and a confocal laser scanning microscope. Ca(2+)/calmodulin-dependent kinase II (CaMKII) activation was assessed by the fluorescence intensity using immunocytochemical procedures. RESULTS Treatment with 1, 10, 30 or 100 μM lamotrigine transiently increased [Ca(2+)](i) in DRG neurones in a dose-dependent manner. Treatment with 100 μM lamotrigine induced a significant (threefold) increase in the Ca(2+) peak in the presence or absence of extracellular Ca(2+). The lamotrigine-induced Ca(2+) increase was abolished or decreased by the treatment with a specific PLC inhibitor (U73122), IP3R antagonist (xestospongin C) or RyR antagonist (dantrolene). In some cells, treatment with 100 μM lamotrigine caused a transient Ca(2+) increase, and the Ca(2+) levels quickly fell to below the basal Ca(2+) level observed prior to lamotrigine application. The decrease in basal Ca(2+) levels was blocked by the treatment with a CaMKII inhibitor (KN93). Immunocytochemical analysis indicated that lamotrigine treatment increased the expression of phosphorylated CaMKII in DRG neurones. CONCLUSION Treatment with lamotrigine increased [Ca(2+)](i) apparently as a result of Ca(2+) release from intracellular stores and CaMKII activity.
Collapse
Affiliation(s)
- E. S. Lee
- Department of Rehabilitation Medicine and Institute of Health Sciences; Gyeongsang National University School of Medicine; Jinju; Korea
| | - J. H. Ryu
- Department of Physiology and Institute of Health Sciences; Gyeongsang National University School of Medicine; Jinju; Korea
| | - E.-J. Kim
- Department of Physiology and Institute of Health Sciences; Gyeongsang National University School of Medicine; Jinju; Korea
| | - G.-T. Kim
- Department of Physiology and Institute of Health Sciences; Gyeongsang National University School of Medicine; Jinju; Korea
| | - Y.-W. Cho
- Department of Physiology and Institute of Health Sciences; Gyeongsang National University School of Medicine; Jinju; Korea
| | - H.-J. Park
- Department of Physiology and Institute of Health Sciences; Gyeongsang National University School of Medicine; Jinju; Korea
| | - H.-M. Tak
- Department of Physiology and Institute of Health Sciences; Gyeongsang National University School of Medicine; Jinju; Korea
| | - J. Han
- Department of Physiology and Institute of Health Sciences; Gyeongsang National University School of Medicine; Jinju; Korea
| | - D. Kang
- Department of Physiology and Institute of Health Sciences; Gyeongsang National University School of Medicine; Jinju; Korea
| |
Collapse
|
29
|
Bagal SK, Brown AD, Cox PJ, Omoto K, Owen RM, Pryde DC, Sidders B, Skerratt SE, Stevens EB, Storer RI, Swain NA. Ion Channels as Therapeutic Targets: A Drug Discovery Perspective. J Med Chem 2012; 56:593-624. [DOI: 10.1021/jm3011433] [Citation(s) in RCA: 198] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Sharan K. Bagal
- Worldwide Medicinal Chemistry, Pfizer Neusentis, The Portway Building, Granta Park,
Great Abington, Cambridge, CB21 6GS, U.K
| | - Alan D. Brown
- Worldwide Medicinal Chemistry, Pfizer Neusentis, The Portway Building, Granta Park,
Great Abington, Cambridge, CB21 6GS, U.K
| | - Peter J. Cox
- Pfizer Neusentis, The
Portway Building, Granta Park, Great Abington, Cambridge, CB21
6GS, U.K
| | - Kiyoyuki Omoto
- Worldwide Medicinal Chemistry, Pfizer Neusentis, The Portway Building, Granta Park,
Great Abington, Cambridge, CB21 6GS, U.K
| | - Robert M. Owen
- Worldwide Medicinal Chemistry, Pfizer Neusentis, The Portway Building, Granta Park,
Great Abington, Cambridge, CB21 6GS, U.K
| | - David C. Pryde
- Worldwide Medicinal Chemistry, Pfizer Neusentis, The Portway Building, Granta Park,
Great Abington, Cambridge, CB21 6GS, U.K
| | - Benjamin Sidders
- Pfizer Neusentis, The
Portway Building, Granta Park, Great Abington, Cambridge, CB21
6GS, U.K
| | - Sarah E. Skerratt
- Worldwide Medicinal Chemistry, Pfizer Neusentis, The Portway Building, Granta Park,
Great Abington, Cambridge, CB21 6GS, U.K
| | - Edward B. Stevens
- Pfizer Neusentis, The
Portway Building, Granta Park, Great Abington, Cambridge, CB21
6GS, U.K
| | - R. Ian Storer
- Worldwide Medicinal Chemistry, Pfizer Neusentis, The Portway Building, Granta Park,
Great Abington, Cambridge, CB21 6GS, U.K
| | - Nigel A. Swain
- Worldwide Medicinal Chemistry, Pfizer Neusentis, The Portway Building, Granta Park,
Great Abington, Cambridge, CB21 6GS, U.K
| |
Collapse
|
30
|
Kim S, Lee Y, Tak HM, Park HJ, Sohn YS, Hwang S, Han J, Kang D, Lee KW. Identification of blocker binding site in mouse TRESK by molecular modeling and mutational studies. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2012. [PMID: 23200789 DOI: 10.1016/j.bbamem.2012.11.021] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
TWIK (tandem-pore domain weak inward rectifying K(+))-related spinal cord K(+) channel, TRESK, a member of the tandem-pore domain K(+) channel family, is the most recently cloned K(2P) channel. TRESK is highly expressed in dorsal root ganglion neuron, a pain sensing neuron, which is a target for analgesics. In this study, a reliable 3D structure for transmembrane (TM) region of mouse TRESK (mTRESK) was constructed, and then the reasonable blocker binding mode of the protein was investigated. The 3D structure of the mTRESK built by homology modeling method was validated with recommend value of stereochemical quality. Based on the validated structure, K(+) channel blocker-bound conformation was obtained by molecular docking and 5ns MD simulation with DPPC lipid bilayer. Our docking study provides the plausible binding mode of known blockers with key interacting residues, especially, F156 and F364. Finally, these modeling results were verified by experimental study with mutation from phenylalanine to alanine (F156A, F364A and F156A/F364A) at the TM2 and TM4. This is the first modeling study for TRESK that can provide structural information of the protein including ligand binding information. These results can be useful in structure based drug design for finding new blockers of the TRESK as potential therapeutic target of pain treatment.
Collapse
Affiliation(s)
- Songmi Kim
- Gyeongsang National University, Gazha-dong, Jinju, Republic of Korea
| | | | | | | | | | | | | | | | | |
Collapse
|
31
|
Enyedi P, Braun G, Czirják G. TRESK: the lone ranger of two-pore domain potassium channels. Mol Cell Endocrinol 2012; 353:75-81. [PMID: 22115960 DOI: 10.1016/j.mce.2011.11.009] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/20/2011] [Revised: 11/02/2011] [Accepted: 11/08/2011] [Indexed: 12/14/2022]
Abstract
TRESK (TWIK-related spinal cord K(+) channel, KCNK18) belongs to the two-pore domain (K2P) background (leak) potassium channel family. Unlike other K2P channels, TRESK is activated by the calcium signal in heterologous expression systems. The activation is mediated by the calcium/calmodulin-dependent protein phosphatase, calcineurin. TRESK is abundantly expressed in dorsal root and trigeminal ganglia. The active ingredient of Sichuan pepper, sanshool, has been suggested to evoke tingling paresthesia by inhibiting the channel in a mechanoreceptor subpopulation of sensory neurons. Recently, dominant-negative mutation of human TRESK was found to be linked to migraine with aura in a large pedigree. It is hoped that future TRESK agonists may prevent or ameliorate the debilitating symptoms of migraine. It will be interesting to see whether the calcineurin-activated K(+) channel maintains normal excitability in the cerebral cortex thereby arresting cortical spreading depression (CSD), or prevents migraine attack only in the trigeminovascular (TGVS) system.
Collapse
Affiliation(s)
- Péter Enyedi
- Department of Physiology, Semmelweis University, Budapest, Hungary.
| | | | | |
Collapse
|
32
|
Braun G, Nemcsics B, Enyedi P, Czirják G. TRESK background K(+) channel is inhibited by PAR-1/MARK microtubule affinity-regulating kinases in Xenopus oocytes. PLoS One 2011; 6:e28119. [PMID: 22145024 PMCID: PMC3228728 DOI: 10.1371/journal.pone.0028119] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2011] [Accepted: 11/01/2011] [Indexed: 12/14/2022] Open
Abstract
TRESK (TWIK-related spinal cord K+ channel, KCNK18) is a major background K+ channel of sensory neurons. Dominant-negative mutation of TRESK is linked to familial migraine. This important two-pore domain K+ channel is uniquely activated by calcineurin. The calcium/calmodulin-dependent protein phosphatase directly binds to the channel and activates TRESK current several-fold in Xenopus oocytes and HEK293 cells. We have recently shown that the kinase, which is responsible for the basal inhibition of the K+ current, is sensitive to the adaptor protein 14-3-3. Therefore we have examined the effect of the 14-3-3-inhibited PAR-1/MARK, microtubule-associated-protein/microtubule affinity-regulating kinase on TRESK in the Xenopus oocyte expression system. MARK1, MARK2 and MARK3 accelerated the return of TRESK current to the resting state after the calcium-dependent activation. Several other serine-threonine kinase types, generally involved in the modulation of other ion channels, failed to influence TRESK current recovery. MARK2 phosphorylated the primary determinant of regulation, the cluster of three adjacent serine residues (S274, 276 and 279) in the intracellular loop of mouse TRESK. In contrast, serine 264, the 14-3-3-binding site of TRESK, was not phosphorylated by the kinase. Thus MARK2 selectively inhibits TRESK activity via the S274/276/279 cluster, but does not affect the direct recruitment of 14-3-3 to the channel. TRESK is the first example of an ion channel phosphorylated by the dynamically membrane-localized MARK kinases, also known as general determinants of cellular polarity. These results raise the possibility that microtubule dynamics is coupled to the regulation of excitability in the neurons, which express TRESK background potassium channel.
Collapse
Affiliation(s)
- Gabriella Braun
- Department of Physiology, Semmelweis University, Budapest, Hungary
| | | | | | | |
Collapse
|
33
|
Baxter P. Channels: exciting developments. Dev Med Child Neurol 2011; 53:577-8. [PMID: 21649649 DOI: 10.1111/j.1469-8749.2011.04019.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
|
34
|
Tulleuda A, Cokic B, Callejo G, Saiani B, Serra J, Gasull X. TRESK channel contribution to nociceptive sensory neurons excitability: modulation by nerve injury. Mol Pain 2011; 7:30. [PMID: 21527011 PMCID: PMC3095542 DOI: 10.1186/1744-8069-7-30] [Citation(s) in RCA: 112] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2011] [Accepted: 04/28/2011] [Indexed: 01/01/2023] Open
Abstract
Background Neuronal hyperexcitability is a crucial phenomenon underlying spontaneous and evoked pain. In invertebrate nociceptors, the S-type leak K+ channel (analogous to TREK-1 in mammals) plays a critical role of in determining neuronal excitability following nerve injury. Few data are available on the role of leak K2P channels after peripheral axotomy in mammals. Results Here we describe that rat sciatic nerve axotomy induces hyperexcitability of L4-L5 DRG sensory neurons and decreases TRESK (K2P18.1) expression, a channel with a major contribution to total leak current in DRGs. While the expression of other channels from the same family did not significantly change, injury markers ATF3 and Cacna2d1 were highly upregulated. Similarly, acute sensory neuron dissociation (in vitro axotomy) produced marked hyperexcitability and similar total background currents compared with neurons injured in vivo. In addition, the sanshool derivative IBA, which blocked TRESK currents in transfected HEK293 cells and DRGs, increased intracellular calcium in 49% of DRG neurons in culture. Most IBA-responding neurons (71%) also responded to the TRPV1 agonist capsaicin, indicating that they were nociceptors. Additional evidence of a biological role of TRESK channels was provided by behavioral evidence of pain (flinching and licking), in vivo electrophysiological evidence of C-nociceptor activation following IBA injection in the rat hindpaw, and increased sensitivity to painful pressure after TRESK knockdown in vivo. Conclusions In summary, our results clearly support an important role of TRESK channels in determining neuronal excitability in specific DRG neurons subpopulations, and show that axonal injury down-regulates TRESK channels, therefore contributing to neuronal hyperexcitability.
Collapse
Affiliation(s)
- Astrid Tulleuda
- Neurophysiology Lab, Dept, Physiological Sciences I, Medical School, University of Barcelona-Institut d'Investigacions Biomèdiques August Pi i Sunyer, Barcelona, Spain
| | | | | | | | | | | |
Collapse
|
35
|
Activation of TREK currents by the neuroprotective agent riluzole in mouse sympathetic neurons. J Neurosci 2011; 31:1375-85. [PMID: 21273422 DOI: 10.1523/jneurosci.2791-10.2011] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Background K2P channels play a key role in stabilizing the resting membrane potential, thereby modulating cell excitability in the central and peripheral somatic nervous system. Whole-cell experiments revealed a riluzole-activated current (I(RIL)), transported by potassium, in mouse superior cervical ganglion (mSCG) neurons. The activation of this current by riluzole, linoleic acid, membrane stretch, and internal acidification, its open rectification and insensitivity to most classic potassium channel blockers, indicated that I(RIL) flows through channels of the TREK [two-pore domain weak inwardly rectifying K channel (TWIK)-related K channel] subfamily. Whole-ganglia and single-cell reverse transcription-PCR demonstrated the presence of TREK-1, TREK-2, and TRAAK (TWIK-related arachidonic acid-activated K(+) channel) mRNA, and the expression of these three proteins was confirmed by immunocytochemistry in mSCG neurons. I(RIL) was enhanced by zinc, inhibited by barium and fluoxetine, but unaffected by quinine and ruthenium red, strongly suggesting that it was carried through TREK-1/2 channels. Consistently, a channel with properties identical with the heterologously expressed TREK-2 was recorded in most (75%) cell-attached patches. These results provide the first evidence for the expression of K2P channels in the mammalian autonomic nervous system, and they extend the impact of these channels to the entire nervous system.
Collapse
|
36
|
Enyedi P, Czirják G. Molecular background of leak K+ currents: two-pore domain potassium channels. Physiol Rev 2010; 90:559-605. [PMID: 20393194 DOI: 10.1152/physrev.00029.2009] [Citation(s) in RCA: 620] [Impact Index Per Article: 44.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Two-pore domain K(+) (K(2P)) channels give rise to leak (also called background) K(+) currents. The well-known role of background K(+) currents is to stabilize the negative resting membrane potential and counterbalance depolarization. However, it has become apparent in the past decade (during the detailed examination of the cloned and corresponding native K(2P) channel types) that this primary hyperpolarizing action is not performed passively. The K(2P) channels are regulated by a wide variety of voltage-independent factors. Basic physicochemical parameters (e.g., pH, temperature, membrane stretch) and also several intracellular signaling pathways substantially and specifically modulate the different members of the six K(2P) channel subfamilies (TWIK, TREK, TASK, TALK, THIK, and TRESK). The deep implication in diverse physiological processes, the circumscribed expression pattern of the different channels, and the interesting pharmacological profile brought the K(2P) channel family into the spotlight. In this review, we focus on the physiological roles of K(2P) channels in the most extensively investigated cell types, with special emphasis on the molecular mechanisms of channel regulation.
Collapse
Affiliation(s)
- Péter Enyedi
- Department of Physiology, Semmelweis University, Budapest, Hungary.
| | | |
Collapse
|
37
|
Lennertz RC, Tsunozaki M, Bautista DM, Stucky CL. Physiological basis of tingling paresthesia evoked by hydroxy-alpha-sanshool. J Neurosci 2010; 30:4353-61. [PMID: 20335471 PMCID: PMC2852189 DOI: 10.1523/jneurosci.4666-09.2010] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2009] [Revised: 12/23/2009] [Accepted: 02/11/2010] [Indexed: 12/15/2022] Open
Abstract
Hydroxy-alpha-sanshool, the active ingredient in plants of the prickly ash plant family, induces robust tingling paresthesia by activating a subset of somatosensory neurons. However, the subtypes and physiological function of sanshool-sensitive neurons remain unknown. Here we use the ex vivo skin-nerve preparation to examine the pattern and intensity with which the sensory terminals of cutaneous neurons respond to hydroxy-alpha-sanshool. We found that sanshool excites virtually all D-hair afferents, a distinct subset of ultrasensitive light-touch receptors in the skin and targets novel populations of Abeta and C fiber nerve afferents. Thus, sanshool provides a novel pharmacological tool for discriminating functional subtypes of cutaneous mechanoreceptors. The identification of sanshool-sensitive fibers represents an essential first step in identifying the cellular and molecular mechanisms underlying tingling paresthesia that accompanies peripheral neuropathy and injury.
Collapse
Affiliation(s)
- Richard C. Lennertz
- Department of Cell Biology, Neurobiology, and Anatomy, Medical College of Wisconsin, Milwaukee, Wisconsin 53226, and
| | - Makoto Tsunozaki
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, California 94720
| | - Diana M. Bautista
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, California 94720
| | - Cheryl L. Stucky
- Department of Cell Biology, Neurobiology, and Anatomy, Medical College of Wisconsin, Milwaukee, Wisconsin 53226, and
| |
Collapse
|
38
|
Czirják G, Enyedi P. TRESK background K(+) channel is inhibited by phosphorylation via two distinct pathways. J Biol Chem 2010; 285:14549-57. [PMID: 20215114 DOI: 10.1074/jbc.m110.102020] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The two-pore domain K(+) channel, TRESK (TWIK-related spinal cord K(+) channel, KCNK18) is directly regulated by the calcium/calmodulin-dependent phosphatase calcineurin and 14-3-3 adaptor proteins. The calcium signal robustly activates the channel via calcineurin, whereas the anchoring of 14-3-3 interferes with the return of the current to the resting state after the activation in Xenopus oocytes. In the present study, we report that the phosphorylation of TRESK at two distinct regulatory regions, the 14-3-3 binding site (Ser-264) and the cluster of three adjacent serine residues (Ser-274, Ser-276, and Ser-279), are responsible for channel inhibition. The phosphorylation of Ser-264 by protein kinase A accelerated the return of the current of S276E mutant TRESK to the resting state after the calcineurin-dependent activation. In the presence of 14-3-3, the basal current of the S276E mutant was reduced, and its calcineurin-dependent activation was augmented, suggesting that the direct binding of the adaptor protein to TRESK contributed to the basal inhibition of the channel under resting conditions. Unexpectedly, we found that 14-3-3 impeded the recovery of the current of S264E mutant TRESK to the resting state after the calcineurin-dependent activation, despite of the mutated 14-3-3 binding site. This suggests that 14-3-3 inhibited the kinase phosphorylating the regulatory cluster of Ser-274, Ser-276, and Ser-279, independently of the direct interaction between TRESK and 14-3-3. In conclusion, two distinct inhibitory kinase pathways converge on TRESK, and their effect on the calcineurin-dependent regulation is differentially modulated by the functional availability of 14-3-3.
Collapse
Affiliation(s)
- Gábor Czirják
- Department of Physiology, Semmelweis University, H-1444 Budapest, Hungary
| | | |
Collapse
|
39
|
Han J, Kang D. TRESK channel as a potential target to treat T-cell mediated immune dysfunction. Biochem Biophys Res Commun 2009; 390:1102-5. [PMID: 19852929 DOI: 10.1016/j.bbrc.2009.10.076] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2009] [Accepted: 10/15/2009] [Indexed: 11/25/2022]
Abstract
In this review, we propose that TRESK background K(+) channel could serve as a potential therapeutic target for T-cell mediated immune dysfunction. TRESK has many immune function-related properties. TRESK is abundantly expressed in the thymus, the spleen, and human leukemic T-lymphocytes. TRESK is highly activated by Ca(2+), calcineurin, acetylcholine, and histamine which induce hypertrophy, whereas TRESK is inhibited by immunosuppressants, such as cyclosporin A and FK506. Cyclosporine A and FK506 target the binding site of nuclear factor of activated T-cells (NFAT) to inhibit calcineurin. Interestingly, TRESK possesses an NFAT-like docking site that is present at its intracellular loop. Calcineurin has been found to interact with TRESK via specific NFAT-like docking site. When the T-cell is activated, calcineurin can bind to the NFAT-docking site of TRESK. The activation of both TRESK and NFAT via Ca(2+)-calcineurin-NFAT/TRESK pathway could modulate the transcription of new genes in addition to regulating several aspects of T-cell function.
Collapse
Affiliation(s)
- Jaehee Han
- Medical Research Center for Neural Dysfunction, Department of Physiology, Institute of Health Sciences, Gyeongsang National University, School of Medicine, Jinju 660-751, Republic of Korea
| | | |
Collapse
|
40
|
Czirják G, Vuity D, Enyedi P. Phosphorylation-dependent binding of 14-3-3 proteins controls TRESK regulation. J Biol Chem 2008; 283:15672-80. [PMID: 18397886 PMCID: PMC3259650 DOI: 10.1074/jbc.m800712200] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2008] [Revised: 04/03/2008] [Indexed: 01/04/2023] Open
Abstract
The two-pore domain K(+) channel, TRESK (TWIK-related spinal cord K(+) channel) is reversibly activated by the calcium/calmodulin-dependent protein phosphatase, calcineurin. In the present study, we report that 14-3-3 proteins directly bind to the intracellular loop of TRESK and control the kinetics of the calcium-dependent regulation of the channel. Coexpression of 14-3-3eta with TRESK blocked, whereas the coexpression of a dominant negative form of 14-3-3eta accelerated the return of the K(+) current to the resting state after the activation mediated by calcineurin in Xenopus oocytes. The direct action of 14-3-3 was spatially restricted to TRESK, since 14-3-3eta was also effective, when it was tethered to the channel by a flexible polyglutamine-containing chain. The effect of both the coexpressed and chained 14-3-3 was alleviated by the microinjection of Ser(P)-Raf259 phosphopeptide that competes with TRESK for binding to 14-3-3. The gamma and eta isoforms of 14-3-3 controlled TRESK regulation, whereas the beta, zeta, epsilon, sigma, and tau isoforms failed to influence the mechanism significantly. Phosphorylation of serine 264 in mouse TRESK was required for the binding of 14-3-3eta. Because 14-3-3 proteins are ubiquitous, they are expected to control the duration of calcineurin-mediated TRESK activation in all the cell types that express the channel, depending on the phosphorylation state of serine 264. This kind of direct control of channel regulation by 14-3-3 is unique within the two-pore domain K(+) channel family.
Collapse
Affiliation(s)
| | | | - Péter Enyedi
- Department of Physiology, Semmelweis University, H-1444 Budapest,
Hungary
| |
Collapse
|