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Orlov NA, Kryukova EV, Efremenko AV, Yakimov SA, Toporova VA, Kirpichnikov MP, Nekrasova OV, Feofanov AV. Interactions of the Kv1.1 Channel with Peptide Pore Blockers: A Fluorescent Analysis on Mammalian Cells. MEMBRANES 2023; 13:645. [PMID: 37505011 PMCID: PMC10383195 DOI: 10.3390/membranes13070645] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2023] [Revised: 06/23/2023] [Accepted: 06/27/2023] [Indexed: 07/29/2023]
Abstract
The voltage-gated potassium channel Kv1.1, which is abundant in the CNS and peripheral nervous system, controls neuronal excitability and neuromuscular transmission and mediates a number of physiological functions in non-excitable cells. The development of some diseases is accompanied by changes in the expression level and/or activity of the channels in particular types of cells. To meet the requirements of studies related to the expression and localization of the Kv1.1 channels, we report on the subnanomolar affinity of hongotoxin 1 N-terminally labeled with Atto 488 fluorophore (A-HgTx) for the Kv1.1 channel and its applicability for fluorescent imaging of the channel in living cells. Taking into consideration the pharmacological potential of the Kv1.1 channel, a fluorescence-based analytical system was developed for the study of peptide ligands that block the ion conductivity of Kv1.1 and are potentially able to correct abnormal activity of the channel. The system is based on analysis of the competitive binding of the studied compounds and A-HgTx to the mKate2-tagged human Kv1.1 (S369T) channel, expressed in the plasma membrane of Neuro2a cells. The system was validated by measuring the affinities of the known Kv1.1-channel peptide blockers, such as agitoxin 2, kaliotoxin 1, hongotoxin 1, and margatoxin. Peptide pore blocker Ce1, from the venom of the scorpion Centruroides elegans, was shown to possess a nanomolar affinity for the Kv1.1 channel. It is reported that interactions of the Kv1.1 channel with the studied peptide blockers are not affected by the transition of the channel from the closed to open state. The conclusion is made that the structural rearrangements accompanying the channel transition into the open state do not change the conformation of the P-loop (including the selectivity filter) involved in the formation of the binding site of the peptide pore blockers.
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Affiliation(s)
- Nikita A Orlov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 117997 Moscow, Russia
- Faculty of Biology, Lomonosov Moscow State University, 119234 Moscow, Russia
| | - Elena V Kryukova
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 117997 Moscow, Russia
| | - Anastasia V Efremenko
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 117997 Moscow, Russia
| | - Sergey A Yakimov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 117997 Moscow, Russia
| | - Victoria A Toporova
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 117997 Moscow, Russia
| | - Mikhail P Kirpichnikov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 117997 Moscow, Russia
- Faculty of Biology, Lomonosov Moscow State University, 119234 Moscow, Russia
| | - Oksana V Nekrasova
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 117997 Moscow, Russia
| | - Alexey V Feofanov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 117997 Moscow, Russia
- Faculty of Biology, Lomonosov Moscow State University, 119234 Moscow, Russia
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D’Adamo MC, Liantonio A, Rolland JF, Pessia M, Imbrici P. Kv1.1 Channelopathies: Pathophysiological Mechanisms and Therapeutic Approaches. Int J Mol Sci 2020; 21:ijms21082935. [PMID: 32331416 PMCID: PMC7215777 DOI: 10.3390/ijms21082935] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Revised: 04/19/2020] [Accepted: 04/20/2020] [Indexed: 12/27/2022] Open
Abstract
Kv1.1 belongs to the Shaker subfamily of voltage-gated potassium channels and acts as a critical regulator of neuronal excitability in the central and peripheral nervous systems. KCNA1 is the only gene that has been associated with episodic ataxia type 1 (EA1), an autosomal dominant disorder characterized by ataxia and myokymia and for which different and variable phenotypes have now been reported. The iterative characterization of channel defects at the molecular, network, and organismal levels contributed to elucidating the functional consequences of KCNA1 mutations and to demonstrate that ataxic attacks and neuromyotonia result from cerebellum and motor nerve alterations. Dysfunctions of the Kv1.1 channel have been also associated with epilepsy and kcna1 knock-out mouse is considered a model of sudden unexpected death in epilepsy. The tissue-specific association of Kv1.1 with other Kv1 members, auxiliary and interacting subunits amplifies Kv1.1 physiological roles and expands the pathogenesis of Kv1.1-associated diseases. In line with the current knowledge, Kv1.1 has been proposed as a novel and promising target for the treatment of brain disorders characterized by hyperexcitability, in the attempt to overcome limited response and side effects of available therapies. This review recounts past and current studies clarifying the roles of Kv1.1 in and beyond the nervous system and its contribution to EA1 and seizure susceptibility as well as its wide pharmacological potential.
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Affiliation(s)
- Maria Cristina D’Adamo
- Department of Physiology and Biochemistry, Faculty of Medicine and Surgery, University of Malta, Msida MDS-2080, Malta; (M.C.D.); (M.P.)
| | - Antonella Liantonio
- Department of Pharmacy–Drug Sciences, University of Bari “Aldo Moro”, 70125 Bari, Italy;
| | | | - Mauro Pessia
- Department of Physiology and Biochemistry, Faculty of Medicine and Surgery, University of Malta, Msida MDS-2080, Malta; (M.C.D.); (M.P.)
- Department of Physiology, College of Medicine and Health Sciences, United Arab Emirates University, Al Ain Po Box 17666, UAE
| | - Paola Imbrici
- Department of Pharmacy–Drug Sciences, University of Bari “Aldo Moro”, 70125 Bari, Italy;
- Correspondence:
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Matsuda H, Mullapudi ST, Yang YHC, Masaki H, Hesselson D, Stainier DYR. Whole-Organism Chemical Screening Identifies Modulators of Pancreatic β-Cell Function. Diabetes 2018; 67:2268-2279. [PMID: 30115653 DOI: 10.2337/db17-1223] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Accepted: 08/07/2018] [Indexed: 11/13/2022]
Abstract
β-Cell loss and dysfunction play a critical role in the progression of type 1 and type 2 diabetes. Identifying new molecules and/or molecular pathways that improve β-cell function and/or increase β-cell mass should significantly contribute to the development of new therapies for diabetes. Using the zebrafish model, we screened 4,640 small molecules to identify modulators of β-cell function. This in vivo strategy identified 84 stimulators of insulin expression, which simultaneously reduced glucose levels. The insulin promoter activation kinetics for 32 of these stimulators were consistent with a direct mode of action. A subset of insulin stimulators, including the antidiabetic drug pioglitazone, induced the coordinated upregulation of gluconeogenic pck1 expression, suggesting functional response to increased insulin action in peripheral tissues. Notably, Kv1.3 inhibitors increased β-cell mass in larval zebrafish and stimulated β-cell function in adult zebrafish and in the streptozotocin-induced hyperglycemic mouse model. In addition, our data indicate that cytoplasmic Kv1.3 regulates β-cell function. Thus, using whole-organism screening, we have identified new small-molecule modulators of β-cell function and glucose metabolism.
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Affiliation(s)
- Hiroki Matsuda
- Department of Developmental Genetics, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
| | - Sri Teja Mullapudi
- Department of Developmental Genetics, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
| | - Yu Hsuan Carol Yang
- Department of Developmental Genetics, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
| | - Hideki Masaki
- Division of Stem Cell Therapy, The Institute of Medical Science, University of Tokyo, Tokyo, Japan
| | - Daniel Hesselson
- Diabetes and Metabolism Division, Garvan Institute of Medical Research, Sydney, New South Wales, Australia
- St Vincent's Clinical School, UNSW Sydney, Sydney, New South Wales, Australia
| | - Didier Y R Stainier
- Department of Developmental Genetics, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
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Imbrici P, Altamura C, Gualandi F, Mangiatordi GF, Neri M, De Maria G, Ferlini A, Padovani A, D'Adamo MC, Nicolotti O, Pessia M, Conte D, Filosto M, Desaphy JF. A novel KCNA1 mutation in a patient with paroxysmal ataxia, myokymia, painful contractures and metabolic dysfunctions. Mol Cell Neurosci 2017; 83:6-12. [PMID: 28666963 DOI: 10.1016/j.mcn.2017.06.006] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2016] [Revised: 04/05/2017] [Accepted: 06/25/2017] [Indexed: 11/26/2022] Open
Abstract
Episodic ataxia type 1 (EA1) is a human dominant neurological syndrome characterized by continuous myokymia, episodic attacks of ataxic gait and spastic contractions of skeletal muscles that can be triggered by emotional stress and fatigue. This rare disease is caused by missense mutations in the KCNA1 gene coding for the neuronal voltage gated potassium channel Kv1.1, which contributes to nerve cell excitability in the cerebellum, hippocampus, cortex and peripheral nervous system. We identified a novel KCNA1 mutation, E283K, in an Italian proband presenting with paroxysmal ataxia and myokymia aggravated by painful contractures and metabolic dysfunctions. The E283K mutation is located in the S3-S4 extracellular linker belonging to the voltage sensor domain of Kv channels. In order to test whether the E283K mutation affects Kv1.1 biophysical properties we transfected HEK293 cells with WT or mutant cDNAs alone or in a 1:1 combination, and recorded relative potassium currents in the whole-cell configuration of patch-clamp. Mutant E283K channels display voltage-dependent activation shifted by 10mV toward positive potentials and kinetics of activation slowed by ~2 fold compared to WT channels. Potassium currents resulting from heteromeric WT/E283K channels show voltage-dependent gating and kinetics of activation intermediate between WT and mutant homomeric channels. Based on homology modeling studies of the mutant E283K, we propose a molecular explanation for the reduced voltage sensitivity and slow channel opening. Overall, our results suggest that the replacement of a negatively charged residue with a positively charged lysine at position 283 in Kv1.1 causes a drop of potassium current that likely accounts for EA-1 symptoms in the heterozygous carrier.
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Affiliation(s)
- Paola Imbrici
- Department of Pharmacy - Drug Sciences, University of Bari Aldo Moro, Bari, Italy.
| | - Concetta Altamura
- Department of Pharmacy - Drug Sciences, University of Bari Aldo Moro, Bari, Italy
| | - Francesca Gualandi
- Logistic Unit of Medical Genetics, Department of Medical Sciences, University-Hospital of Ferrara, Italy
| | | | - Marcella Neri
- Logistic Unit of Medical Genetics, Department of Medical Sciences, University-Hospital of Ferrara, Italy
| | | | - Alessandra Ferlini
- Logistic Unit of Medical Genetics, Department of Medical Sciences, University-Hospital of Ferrara, Italy
| | - Alessandro Padovani
- Center for Neuromuscular Diseases and Neuropathies, Unit of Neurology, ASST "Spedali Civili", and University of Brescia, Brescia, Italy
| | - Maria Cristina D'Adamo
- Faculty of Medicine, Department of Physiology and Biochemistry, University of Malta, MSD-2080 Msida, Malta
| | - Orazio Nicolotti
- Department of Pharmacy - Drug Sciences, University of Bari Aldo Moro, Bari, Italy
| | - Mauro Pessia
- Faculty of Medicine, Department of Physiology and Biochemistry, University of Malta, MSD-2080 Msida, Malta; Department of Experimental Medicine, Section of Physiology & Biochemistry, University of Perugia School of Medicine, Perugia, Italy
| | - Diana Conte
- Department of Pharmacy - Drug Sciences, University of Bari Aldo Moro, Bari, Italy
| | - Massimiliano Filosto
- Center for Neuromuscular Diseases and Neuropathies, Unit of Neurology, ASST "Spedali Civili", and University of Brescia, Brescia, Italy
| | - Jean-Francois Desaphy
- Department of Biomedical Sciences and Human Oncology, University of Bari Aldo Moro, Bari, Italy
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Strodthoff D, Ma Z, Wirström T, Strawbridge RJ, Ketelhuth DFJ, Engel D, Clarke R, Falkmer S, Hamsten A, Hansson GK, Björklund A, Lundberg AM. Toll-Like Receptor 3 Influences Glucose Homeostasis and β-Cell Insulin Secretion. Diabetes 2015; 64:3425-38. [PMID: 25918231 DOI: 10.2337/db14-0838] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/26/2014] [Accepted: 04/17/2015] [Indexed: 11/13/2022]
Abstract
Toll-like receptors (TLRs) have been implicated in the pathogenesis of type 2 diabetes. We examined the function of TLR3 in glucose metabolism and type 2 diabetes-related phenotypes in animals and humans. TLR3 is highly expressed in the pancreas, suggesting that it can influence metabolism. Using a diet-induced obesity model, we show that TLR3-deficient mice had enhanced glycemic control, facilitated by elevated insulin secretion. Despite having high insulin levels, Tlr3(-/-) mice did not experience disturbances in whole-body insulin sensitivity, suggesting that they have a robust metabolic system that manages increased insulin secretion. Increase in insulin secretion was associated with upregulation of islet glucose phosphorylation as well as exocytotic protein VAMP-2 in Tlr3(-/-) islets. TLR3 deficiency also modified the plasma lipid profile, decreasing VLDL levels due to decreased triglyceride biosynthesis. Moreover, a meta-analysis of two healthy human populations showed that a missense single nucleotide polymorphism in TLR3 (encoding L412F) was linked to elevated insulin levels, consistent with our experimental findings. In conclusion, our results increase the understanding of the function of innate receptors in metabolic disorders and implicate TLR3 as a key control system in metabolic regulation.
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Affiliation(s)
- Daniela Strodthoff
- Cardiovascular Research Unit, Center for Molecular Medicine, Department of Medicine, Karolinska Institutet, Stockholm, Sweden Metabolism Unit, Department of Medicine, and Department of Endocrinology, Metabolism and Diabetes, Karolinska Institutet at Karolinska University Hospital Huddinge, Karolinska Institutet/AstraZeneca Integrated Cardio Metabolic Center and Center for Innovative Medicine, NOVUM, Stockholm, Sweden
| | - Zuheng Ma
- Endocrinology and Diabetes Unit, Department of Molecular Medicine and Surgery, Karolinska Institutet, Karolinska University Hospital Solna, Stockholm, Sweden
| | - Tina Wirström
- Endocrinology and Diabetes Unit, Department of Molecular Medicine and Surgery, Karolinska Institutet, Karolinska University Hospital Solna, Stockholm, Sweden
| | - Rona J Strawbridge
- Atherosclerosis Research Unit, Center for Molecular Medicine, Department of Medicine Solna, Karolinska Institutet, Karolinska University Hospital Solna, Stockholm, Sweden
| | - Daniel F J Ketelhuth
- Cardiovascular Research Unit, Center for Molecular Medicine, Department of Medicine, Karolinska Institutet, Stockholm, Sweden
| | - David Engel
- Cardiovascular Research Unit, Center for Molecular Medicine, Department of Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Robert Clarke
- Clinical Trial Service Unit and Epidemiological Studies Unit, University of Oxford, Oxford, U.K
| | - Sture Falkmer
- Laboratory of Pathology and Clinical Cytology, Ryhov Hospital, Jönköping, Sweden
| | - Anders Hamsten
- Atherosclerosis Research Unit, Center for Molecular Medicine, Department of Medicine Solna, Karolinska Institutet, Karolinska University Hospital Solna, Stockholm, Sweden
| | - Göran K Hansson
- Cardiovascular Research Unit, Center for Molecular Medicine, Department of Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Anneli Björklund
- Endocrinology and Diabetes Unit, Department of Molecular Medicine and Surgery, Karolinska Institutet, Karolinska University Hospital Solna, Stockholm, Sweden
| | - Anna M Lundberg
- Cardiovascular Research Unit, Center for Molecular Medicine, Department of Medicine, Karolinska Institutet, Stockholm, Sweden
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Anderson D, Cordell HJ, Fakiola M, Francis RW, Syn G, Scaman ESH, Davis E, Miles SJ, McLeay T, Jamieson SE, Blackwell JM. First genome-wide association study in an Australian aboriginal population provides insights into genetic risk factors for body mass index and type 2 diabetes. PLoS One 2015; 10:e0119333. [PMID: 25760438 PMCID: PMC4356593 DOI: 10.1371/journal.pone.0119333] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2014] [Accepted: 01/28/2015] [Indexed: 12/15/2022] Open
Abstract
A body mass index (BMI) >22kg/m2 is a risk factor for type 2 diabetes (T2D) in Aboriginal Australians. To identify loci associated with BMI and T2D we undertook a genome-wide association study using 1,075,436 quality-controlled single nucleotide polymorphisms (SNPs) genotyped (Illumina 2.5M Duo Beadchip) in 402 individuals in extended pedigrees from a Western Australian Aboriginal community. Imputation using the thousand genomes (1000G) reference panel extended the analysis to 6,724,284 post quality-control autosomal SNPs. No associations achieved genome-wide significance, commonly accepted as P<5x10-8. Nevertheless, genes/pathways in common with other ethnicities were identified despite the arrival of Aboriginal people in Australia >45,000 years ago. The top hit (rs10868204 Pgenotyped = 1.50x10-6; rs11140653 Pimputed_1000G = 2.90x10-7) for BMI lies 5’ of NTRK2, the type 2 neurotrophic tyrosine kinase receptor for brain-derived neurotrophic factor (BDNF) that regulates energy balance downstream of melanocortin-4 receptor (MC4R). PIK3C2G (rs12816270 Pgenotyped = 8.06x10-6; rs10841048 Pimputed_1000G = 6.28x10-7) was associated with BMI, but not with T2D as reported elsewhere. BMI also associated with CNTNAP2 (rs6960319 Pgenotyped = 4.65x10-5; rs13225016 Pimputed_1000G = 6.57x10-5), previously identified as the strongest gene-by-environment interaction for BMI in African-Americans. The top hit (rs11240074 Pgenotyped = 5.59x10-6, Pimputed_1000G = 5.73x10-6) for T2D lies 5’ of BCL9 that, along with TCF7L2, promotes beta-catenin’s transcriptional activity in the WNT signaling pathway. Additional hits occurred in genes affecting pancreatic (KCNJ6, KCNA1) and/or GABA (GABRR1, KCNA1) functions. Notable associations observed for genes previously identified at genome-wide significance in other populations included MC4R (Pgenotyped = 4.49x10-4) for BMI and IGF2BP2 Pimputed_1000G = 2.55x10-6) for T2D. Our results may provide novel functional leads in understanding disease pathogenesis in this Australian Aboriginal population.
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Affiliation(s)
- Denise Anderson
- Telethon Kids Institute, The University of Western Australia, Subiaco, Western Australia, 6008, Australia
| | - Heather J. Cordell
- Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne, NE1 3BZ, United Kingdom
| | - Michaela Fakiola
- Telethon Kids Institute, The University of Western Australia, Subiaco, Western Australia, 6008, Australia
- Cambridge Institute for Medical Research, Department of Medicine, and Department of Pathology, University of Cambridge, Cambridge, United Kingdom
| | - Richard W. Francis
- Telethon Kids Institute, The University of Western Australia, Subiaco, Western Australia, 6008, Australia
| | - Genevieve Syn
- Telethon Kids Institute, The University of Western Australia, Subiaco, Western Australia, 6008, Australia
| | - Elizabeth S. H. Scaman
- Telethon Kids Institute, The University of Western Australia, Subiaco, Western Australia, 6008, Australia
| | - Elizabeth Davis
- Telethon Kids Institute, The University of Western Australia, Subiaco, Western Australia, 6008, Australia
- Department of Endocrinology and Diabetes, Princess Margaret Hospital for Children, Subiaco, Western Australia, 6008, Australia
| | - Simon J. Miles
- Ngangganawili Aboriginal Health Service, Wiluna, Western Australia, 6646, Australia
| | - Toby McLeay
- Ngangganawili Aboriginal Health Service, Wiluna, Western Australia, 6646, Australia
| | - Sarra E. Jamieson
- Telethon Kids Institute, The University of Western Australia, Subiaco, Western Australia, 6008, Australia
| | - Jenefer M. Blackwell
- Telethon Kids Institute, The University of Western Australia, Subiaco, Western Australia, 6008, Australia
- Cambridge Institute for Medical Research, Department of Medicine, and Department of Pathology, University of Cambridge, Cambridge, United Kingdom
- * E-mail:
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Bartok A, Toth A, Somodi S, Szanto TG, Hajdu P, Panyi G, Varga Z. Margatoxin is a non-selective inhibitor of human Kv1.3 K+ channels. Toxicon 2014; 87:6-16. [PMID: 24878374 DOI: 10.1016/j.toxicon.2014.05.002] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2014] [Revised: 05/07/2014] [Accepted: 05/12/2014] [Indexed: 11/28/2022]
Abstract
Margatoxin (MgTx), an alpha-KTx scorpion toxin, is considered a selective inhibitor of the Kv1.3K + channel. This peptide is widely used in ion channel research; however, a comprehensive study of its selectivity with electrophysiological methods has not been published yet. The lack of selectivity might lead to undesired side effects upon therapeutic application or may lead to incorrect conclusion regarding the role of a particular ion channel in a physiological or pathophysiological response either in vitro or in vivo. Using the patch-clamp technique we characterized the selectivity profile of MgTx using L929 cells expressing mKv1.1 channels, human peripheral lymphocytes expressing Kv1.3 channels and transiently transfected tsA201 cells expressing hKv1.1, hKv1.2, hKv1.3, hKv1.4-IR, hKv1.5, hKv1.6, hKv1.7, rKv2.1, Shaker-IR, hERG, hKCa1.1, hKCa3.1 and hNav1.5 channels. MgTx is indeed a high affinity inhibitor of Kv1.3 (Kd = 11.7 pM) but is not selective, it inhibits the Kv1.2 channel with similar affinity (Kd = 6.4 pM) and Kv1.1 in the nanomolar range (Kd = 4.2 nM). Based on our comprehensive data MgTX has to be considered a non-selective Kv1.3 inhibitor, and thus, experiments aiming at elucidating the significance of Kv1.3 in in vitro or in vivo physiological responses have to be carefully evaluated.
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Affiliation(s)
- Adam Bartok
- Department of Biophysics and Cell Biology, University of Debrecen, Faculty of Medicine, 98 Nagyerdei krt., Debrecen 4032, Hungary.
| | - Agnes Toth
- Department of Biophysics and Cell Biology, University of Debrecen, Faculty of Medicine, 98 Nagyerdei krt., Debrecen 4032, Hungary.
| | - Sandor Somodi
- Division of Metabolic Diseases, Department of Internal Medicine, University of Debrecen, 98 Nagyerdei krt., Debrecen 4032, Hungary.
| | - Tibor G Szanto
- Department of Biophysics and Cell Biology, University of Debrecen, Faculty of Medicine, 98 Nagyerdei krt., Debrecen 4032, Hungary.
| | - Peter Hajdu
- Department of Biophysics and Cell Biology, University of Debrecen, Faculty of Dentistry, 98 Nagyerdei krt., Debrecen 4032, Hungary.
| | - Gyorgy Panyi
- Department of Biophysics and Cell Biology, University of Debrecen, Faculty of Medicine, 98 Nagyerdei krt., Debrecen 4032, Hungary; MTA-DE Cell Biology and Signaling Research Group, 4032 Debrecen, Egyetem tér 1, Hungary. http://biophys.med.unideb.hu/en/node/311
| | - Zoltan Varga
- Department of Biophysics and Cell Biology, University of Debrecen, Faculty of Medicine, 98 Nagyerdei krt., Debrecen 4032, Hungary.
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