1
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Doan TNA, Cowley JM, Phillips AL, Briffa JF, Leemaqz SY, Burton RA, Romano T, Wlodek ME, Bianco-Miotto T. Imprinted gene alterations in the kidneys of growth restricted offspring may be mediated by a long non-coding RNA. Epigenetics 2024; 19:2294516. [PMID: 38126131 PMCID: PMC10761017 DOI: 10.1080/15592294.2023.2294516] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Accepted: 12/06/2023] [Indexed: 12/23/2023] Open
Abstract
Altered epigenetic mechanisms have been previously reported in growth restricted offspring whose mothers experienced environmental insults during pregnancy in both human and rodent studies. We previously reported changes in the expression of the DNA methyltransferase Dnmt3a and the imprinted genes Cdkn1c (Cyclin-dependent kinase inhibitor 1C) and Kcnq1 (Potassium voltage-gated channel subfamily Q member 1) in the kidney tissue of growth restricted rats whose mothers had uteroplacental insufficiency induced on day 18 of gestation, at both embryonic day 20 (E20) and postnatal day 1 (PN1). To determine the mechanisms responsible for changes in the expression of these imprinted genes, we investigated DNA methylation of KvDMR1, an imprinting control region (ICR) that includes the promoter of the antisense long non-coding RNA Kcnq1ot1 (Kcnq1 opposite strand/antisense transcript 1). Kcnq1ot1 expression decreased by 51% in growth restricted offspring compared to sham at PN1. Interestingly, there was a negative correlation between Kcnq1ot1 and Kcnq1 in the E20 growth restricted group (Spearman's ρ = 0.014). No correlation was observed between Kcnq1ot1 and Cdkn1c expression in either group at any time point. Additionally, there was a 11.25% decrease in the methylation level at one CpG site within KvDMR1 ICR. This study, together with others in the literature, supports that long non-coding RNAs may mediate changes seen in tissues of growth restricted offspring.
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Affiliation(s)
- Thu N. A. Doan
- School of Agriculture, Food and Wine, & Waite Research Institute, University of Adelaide, Adelaide, South Australia, Australia
- Robinson Research Institute, University of Adelaide, Adelaide, South Australia, Australia
| | - James M. Cowley
- School of Agriculture, Food and Wine, & Waite Research Institute, University of Adelaide, Adelaide, South Australia, Australia
| | - Aaron L. Phillips
- School of Agriculture, Food and Wine, & Waite Research Institute, University of Adelaide, Adelaide, South Australia, Australia
| | - Jessica F. Briffa
- Department of Anatomy and Physiology, The University of Melbourne, Parkville, Victoria, Australia
| | - Shalem Y. Leemaqz
- Robinson Research Institute, University of Adelaide, Adelaide, South Australia, Australia
- SAHMRI Women and Kids, South Australian Health & Medical Research Institute, Adelaide, South Australia, Australia
- College of Medicine and Public Health, Flinders University, Bedford Park, SA, Australia
| | - Rachel A. Burton
- School of Agriculture, Food and Wine, & Waite Research Institute, University of Adelaide, Adelaide, South Australia, Australia
| | - Tania Romano
- Department of Physiology, Anatomy and Microbiology, La Trobe University, Bundoora, Victoria, Australia
| | - Mary E. Wlodek
- Department of Anatomy and Physiology, The University of Melbourne, Parkville, Victoria, Australia
- Department of Obstetrics and Gynaecology, The University of Melbourne, Parkville, Victoria, Australia
| | - Tina Bianco-Miotto
- School of Agriculture, Food and Wine, & Waite Research Institute, University of Adelaide, Adelaide, South Australia, Australia
- Robinson Research Institute, University of Adelaide, Adelaide, South Australia, Australia
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2
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Li B, Karlova M, Zhang H, Pustovit OB, Mai L, Novoseletsky V, Podolyak D, Zaklyazminskaya EV, Abramochkin DV, Sokolova OS. A mutation in the cardiac KV7.1 channel possibly disrupts interaction with Yotiao protein. Biochem Biophys Res Commun 2024; 714:149947. [PMID: 38657442 DOI: 10.1016/j.bbrc.2024.149947] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2024] [Revised: 04/08/2024] [Accepted: 04/15/2024] [Indexed: 04/26/2024]
Abstract
Here, we characterized the p.Arg583His (R583H) Kv7.1 mutation, identified in two unrelated families suffered from LQT syndrome. This mutation is located in the HС-HD linker of the cytoplasmic portion of the Kv7.1 channel. This linker, together with HD helix are responsible for binding the A-kinase anchoring protein 9 (AKAP9), Yotiao. We studied the electrophysiological characteristics of the mutated channel expressed in CHO-K1 along with KCNE1 subunit and Yotiao protein, using the whole-cell patch-clamp technique. We found that R583H mutation, even at the heterozygous state, impedes IKs activation. Molecular modeling showed that HС and HD helixes of the C-terminal part of Kv7.1 channel are swapped along the C-terminus length of the channel and that R583 position is exposed to the outer surface of HC-HD tandem coiled-coil. Interestingly, the adenylate cyclase activator, forskolin had a smaller effect on the mutant channel comparing with the WT protein, suggesting that R583H mutation may disrupt the interaction of the channel with the adaptor protein Yotiao and, therefore, may impair phosphorylation of the KCNQ1 channel.
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Affiliation(s)
- Bowen Li
- Department of Biology, MSU-BIT University, Shenzhen, Guangdong Province, China
| | - Maria Karlova
- Department of Biology, Moscow Lomonosov University, Moscow, Russia
| | - Han Zhang
- Department of Biology, MSU-BIT University, Shenzhen, Guangdong Province, China
| | | | - Lisha Mai
- Department of Biology, MSU-BIT University, Shenzhen, Guangdong Province, China
| | - Valery Novoseletsky
- Department of Biology, MSU-BIT University, Shenzhen, Guangdong Province, China
| | - Dmitry Podolyak
- Petrovsky Russian Scientific Center for Surgery, Moscow, Russia
| | | | | | - Olga S Sokolova
- Department of Biology, MSU-BIT University, Shenzhen, Guangdong Province, China; Department of Biology, Moscow Lomonosov University, Moscow, Russia.
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3
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Sorensen CM, Salomonsson M, Lubberding AF, Holstein‐Rathlou N. The renal vasodilatation from β-adrenergic activation in vivo in rats is not driven by K V7 and BK Ca channels. Exp Physiol 2024; 109:791-803. [PMID: 38460127 PMCID: PMC11061631 DOI: 10.1113/ep091618] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Accepted: 02/21/2024] [Indexed: 03/11/2024]
Abstract
The mechanisms behind renal vasodilatation elicited by stimulation of β-adrenergic receptors are not clarified. As several classes of K channels are potentially activated, we tested the hypothesis that KV7 and BKCa channels contribute to the decreased renal vascular tone in vivo and in vitro. Changes in renal blood flow (RBF) during β-adrenergic stimulation were measured in anaesthetized rats using an ultrasonic flow probe. The isometric tension of segmental arteries from normo- and hypertensive rats and segmental arteries from wild-type mice and mice lacking functional KV7.1 channels was examined in a wire-myograph. The β-adrenergic agonist isoprenaline increased RBF significantly in vivo. Neither activation nor inhibition of KV7 and BKCa channels affected the β-adrenergic RBF response. In segmental arteries from normo- and hypertensive rats, inhibition of KV7 channels significantly decreased the β-adrenergic vasorelaxation. However, inhibiting BKCa channels was equally effective in reducing the β-adrenergic vasorelaxation. The β-adrenergic vasorelaxation was not different between segmental arteries from wild-type mice and mice lacking KV7.1 channels. As opposed to rats, inhibition of KV7 channels did not affect the murine β-adrenergic vasorelaxation. Although inhibition and activation of KV7 channels or BKCa channels significantly changed baseline RBF in vivo, none of the treatments affected β-adrenergic vasodilatation. In isolated segmental arteries, however, inhibition of KV7 and BKCa channels significantly reduced the β-adrenergic vasorelaxation, indicating that the regulation of RBF in vivo is driven by several actors in order to maintain an adequate RBF. Our data illustrates the challenge in extrapolating results from in vitro to in vivo conditions.
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Affiliation(s)
- Charlotte Mehlin Sorensen
- Department of Biomedical Sciences, Physiology of Circulation, Kidney and LungUniversity of CopenhagenCopenhagenDenmark
| | | | - Anniek Frederike Lubberding
- Department of Biomedical Sciences, Physiology of Inflammation, Metabolism and OxidationUniversity of CopenhagenCopenhagenDenmark
| | - Niels‐Henrik Holstein‐Rathlou
- Department of Biomedical Sciences, Physiology of Circulation, Kidney and LungUniversity of CopenhagenCopenhagenDenmark
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Cen Y, Zhou T, Chen S, Deng Z, Wang J, Ma N, Zhang S. Generation of an induced pluripotent stem cell line from patient with atrial fibrillation with KCNQ1 p.Ser209Pro mutation. Stem Cell Res 2024; 76:103336. [PMID: 38341987 DOI: 10.1016/j.scr.2024.103336] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/02/2024] [Accepted: 02/04/2024] [Indexed: 02/13/2024] Open
Abstract
Gain-of-function mutations in the KCNQ1 gene can cause atrial fibrillation. In this study, we generated an induced stem cell line (GRCHJUi001) from one member of an atrial fibrillation family line, whom had heterozygous mutation in the KCNQ1 gene c.625 T > C (p.Ser209Pro), and the cell line showed maintenance of stem cells characterized by morphology, normal karyotype, and pluripotency.
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Affiliation(s)
- YunGuang Cen
- Department Of Cardiology,Guangzhou Red Cross Hospital of Jinan University, Guangzhou 510220, China; Geriatric Center, Hainan General Hospital (Hainan Affiliated Hospital of Hainan Medical University), Haikou, Hainan 570311, China
| | - TianCheng Zhou
- CAS Key Laboratory of Regenerative Biology, South China Institute for Stem Cell Biology and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou 510530, China
| | - SongSheng Chen
- Department Of Cardiology,Guangzhou Red Cross Hospital of Jinan University, Guangzhou 510220, China
| | - ZhanYu Deng
- Department Of Cardiology,Guangzhou Red Cross Hospital of Jinan University, Guangzhou 510220, China
| | - JianShuo Wang
- Department Of Cardiology,Guangzhou Red Cross Hospital of Jinan University, Guangzhou 510220, China
| | - Ning Ma
- School of Basic Medical Sciences, Guangzhou Laboratory, Guangzhou Medical University, Guangzhou 510005, China
| | - ShaoHeng Zhang
- Department Of Cardiology,Guangzhou Red Cross Hospital of Jinan University, Guangzhou 510220, China.
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Jowais JJ, Yazdi S, Golluscio A, Olivier-Meo V, Liin SI, Larsson HP. Mechanistic understanding of KCNQ1 activating polyunsaturated fatty acid analogs. J Gen Physiol 2023; 155:e202313339. [PMID: 37526928 PMCID: PMC10394376 DOI: 10.1085/jgp.202313339] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Revised: 05/02/2023] [Accepted: 07/18/2023] [Indexed: 08/02/2023] Open
Abstract
The KCNQ1 channel is important for the repolarization phase of the cardiac action potential. Loss of function mutations in KCNQ1 can cause long QT syndrome (LQTS), which can lead to cardiac arrythmia and even sudden cardiac death. We have previously shown that polyunsaturated fatty acids (PUFAs) and PUFA analogs can activate the cardiac KCNQ1 channel, making them potential therapeutics for the treatment of LQTS. PUFAs bind to KCNQ1 at two different binding sites: one at the voltage sensor (Site I) and one at the pore (Site II). PUFA interaction at Site I shifts the voltage dependence of the channel to the left, while interaction at Site II increases maximal conductance. The PUFA analogs, linoleic-glycine and linoleic-tyrosine, are more effective than linoleic acid at Site I, but less effective at Site II. Using both simulations and experiments, we find that the larger head groups of linoleic-glycine and linoleic-tyrosine interact with more residues than the smaller linoleic acid at Site I. We propose that this will stabilize the negatively charged PUFA head group in a position to better interact electrostatically with the positively charges in the voltage sensor. In contrast, the larger head groups of linoleic-glycine and linoleic-tyrosine compared with linoleic acid prevent a close fit of these PUFA analogs in Site II, which is more confined. In addition, we identify several KCNQ1 residues as critical PUFA-analog binding residues, thereby providing molecular models of specific interactions between PUFA analogs and KCNQ1. These interactions will aid in future drug development based on PUFA-KCNQ1 channel interactions.
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Affiliation(s)
- Jessica J. Jowais
- Department of Physiology and Biophysics, University of Miami, Miami, FL, USA
| | - Samira Yazdi
- Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden
| | - Alessia Golluscio
- Department of Physiology and Biophysics, University of Miami, Miami, FL, USA
| | - Vanessa Olivier-Meo
- Department of Physiology and Biophysics, University of Miami, Miami, FL, USA
| | - Sara I. Liin
- Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden
| | - H. Peter Larsson
- Department of Physiology and Biophysics, University of Miami, Miami, FL, USA
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6
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Haddadi A, Farhadi P, Fatemi R, Mohamadynejad P, Moghanibashi M. Differential expression of KCNQ1 and ATP4A genes according to the sex and age in the stomach. Nucleosides Nucleotides Nucleic Acids 2023; 42:1019-1027. [PMID: 37367232 DOI: 10.1080/15257770.2023.2228371] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Revised: 06/12/2023] [Accepted: 06/18/2023] [Indexed: 06/28/2023]
Abstract
We compared the expression of six genes in stomach tissue samples between healthy men and women in different age groups to study sexually dimorphic gene expression. Real-Time RT-PCR was used to compare gene expression between men and women. Our results showed that the expression of KCNQ1 (p = 0.01) was significantly higher in non-menopausal women compared to post-menopausal women. In addition, the expression level of the ATP4A gene in men under 35 years was significantly higher than in men above 50 (p = 0.026). Sexually and age dimorphic gene expression in some genes throughout life may affect gastric function.
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Affiliation(s)
- Azadeh Haddadi
- Department of Biology, Faculty of Basic Sciences, Shahrekord Branch, Islamic Azad University, Shahrekord, Iran
| | - Pegah Farhadi
- Department of Biology, Faculty of Basic Sciences, Shahrekord Branch, Islamic Azad University, Shahrekord, Iran
| | - Raziyeh Fatemi
- Department of Biology, Faculty of Basic Sciences, Shahrekord Branch, Islamic Azad University, Shahrekord, Iran
| | - Parisa Mohamadynejad
- Department of Biology, Faculty of Basic Sciences, Shahrekord Branch, Islamic Azad University, Shahrekord, Iran
| | - Mehdi Moghanibashi
- Department of Genetics, Faculty of Medicine, Kazerun Branch, Islamic Azad University, Kazerun, Iran
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7
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Verkerk AO, Wilders R. Human Sinoatrial Node Pacemaker Activity: Role of the Slow Component of the Delayed Rectifier K + Current, I Ks. Int J Mol Sci 2023; 24:7264. [PMID: 37108427 PMCID: PMC10138838 DOI: 10.3390/ijms24087264] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Revised: 04/07/2023] [Accepted: 04/11/2023] [Indexed: 04/29/2023] Open
Abstract
The pacemaker activity of the sinoatrial node (SAN) has been studied extensively in animal species but is virtually unexplored in humans. Here we assess the role of the slowly activating component of the delayed rectifier K+ current (IKs) in human SAN pacemaker activity and its dependence on heart rate and β-adrenergic stimulation. HEK-293 cells were transiently transfected with wild-type KCNQ1 and KCNE1 cDNA, encoding the α- and β-subunits of the IKs channel, respectively. KCNQ1/KCNE1 currents were recorded both during a traditional voltage clamp and during an action potential (AP) clamp with human SAN-like APs. Forskolin (10 µmol/L) was used to increase the intracellular cAMP level, thus mimicking β-adrenergic stimulation. The experimentally observed effects were evaluated in the Fabbri-Severi computer model of an isolated human SAN cell. Transfected HEK-293 cells displayed large IKs-like outward currents in response to depolarizing voltage clamp steps. Forskolin significantly increased the current density and significantly shifted the half-maximal activation voltage towards more negative potentials. Furthermore, forskolin significantly accelerated activation without affecting the rate of deactivation. During an AP clamp, the KCNQ1/KCNE1 current was substantial during the AP phase, but relatively small during diastolic depolarization. In the presence of forskolin, the KCNQ1/KCNE1 current during both the AP phase and diastolic depolarization increased, resulting in a clearly active KCNQ1/KCNE1 current during diastolic depolarization, particularly at shorter cycle lengths. Computer simulations demonstrated that IKs reduces the intrinsic beating rate through its slowing effect on diastolic depolarization at all levels of autonomic tone and that gain-of-function mutations in KCNQ1 may exert a marked bradycardic effect during vagal tone. In conclusion, IKs is active during human SAN pacemaker activity and has a strong dependence on heart rate and cAMP level, with a prominent role at all levels of autonomic tone.
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Affiliation(s)
- Arie O. Verkerk
- Department of Medical Biology, Amsterdam Cardiovascular Sciences, Amsterdam UMC, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands;
- Department of Experimental Cardiology, Heart Center, Amsterdam Cardiovascular Sciences, Amsterdam UMC, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
| | - Ronald Wilders
- Department of Medical Biology, Amsterdam Cardiovascular Sciences, Amsterdam UMC, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands;
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Dellin M, Rohrbeck I, Asrani P, Schreiber JA, Ritter N, Glorius F, Wünsch B, Budde T, Temme L, Strünker T, Stallmeyer B, Tüttelmann F, Meuth SG, Spehr M, Matschke J, Steinbicker A, Gatsogiannis C, Stoll R, Strutz-Seebohm N, Seebohm G. The second PI(3,5)P 2 binding site in the S0 helix of KCNQ1 stabilizes PIP 2-at the primary PI1 site with potential consequences on intermediate-to-open state transition. Biol Chem 2023; 404:241-254. [PMID: 36809224 DOI: 10.1515/hsz-2022-0247] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Accepted: 12/13/2022] [Indexed: 02/23/2023]
Abstract
The Phosphatidylinositol 3-phosphate 5-kinase Type III PIKfyve is the main source for selectively generated phosphatidylinositol 3,5-bisphosphate (PI(3,5)P2), a known regulator of membrane protein trafficking. PI(3,5)P2 facilitates the cardiac KCNQ1/KCNE1 channel plasma membrane abundance and therewith increases the macroscopic current amplitude. Functional-physical interaction of PI(3,5)P2 with membrane proteins and its structural impact is not sufficiently understood. This study aimed to identify molecular interaction sites and stimulatory mechanisms of the KCNQ1/KCNE1 channel via the PIKfyve-PI(3,5)P2 axis. Mutational scanning at the intracellular membrane leaflet and nuclear magnetic resonance (NMR) spectroscopy identified two PI(3,5)P2 binding sites, the known PIP2 site PS1 and the newly identified N-terminal α-helix S0 as relevant for functional PIKfyve effects. Cd2+ coordination to engineered cysteines and molecular modeling suggest that repositioning of S0 stabilizes the channel s open state, an effect strictly dependent on parallel binding of PI(3,5)P2 to both sites.
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Affiliation(s)
- Maurice Dellin
- IfGH-Cellular Electrophysiology, Department of Cardiology and Angiology, University Hospital of Münster, Robert-Koch Str. 45, D-48149, Münster, Germany
| | - Ina Rohrbeck
- IfGH-Cellular Electrophysiology, Department of Cardiology and Angiology, University Hospital of Münster, Robert-Koch Str. 45, D-48149, Münster, Germany
| | - Purva Asrani
- Faculty of Chemistry and Biochemistry, Biomolecular NMR Spectroscopy and RUBiospek|NMR, Ruhr University of Bochum, Universitätsstraße 150, D-44780, Bochum, Germany
| | - Julian A Schreiber
- IfGH-Cellular Electrophysiology, Department of Cardiology and Angiology, University Hospital of Münster, Robert-Koch Str. 45, D-48149, Münster, Germany
- Institut für Pharmazeutische und Medizinische Chemie, Westfälische Wilhelms-Universität Münster, Corrensstraße 48, D-48149, Münster, Germany
| | - Nadine Ritter
- IfGH-Cellular Electrophysiology, Department of Cardiology and Angiology, University Hospital of Münster, Robert-Koch Str. 45, D-48149, Münster, Germany
- GRK 2515, Chemical biology of ion channels (Chembion), Westfälische Wilhelms-Universität Münster, Münster, Germany
| | - Frank Glorius
- GRK 2515, Chemical biology of ion channels (Chembion), Westfälische Wilhelms-Universität Münster, Münster, Germany
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstrasse 40, D-48149, Münster, Germany
| | - Bernhard Wünsch
- Institut für Pharmazeutische und Medizinische Chemie, Westfälische Wilhelms-Universität Münster, Corrensstraße 48, D-48149, Münster, Germany
- GRK 2515, Chemical biology of ion channels (Chembion), Westfälische Wilhelms-Universität Münster, Münster, Germany
| | - Thomas Budde
- GRK 2515, Chemical biology of ion channels (Chembion), Westfälische Wilhelms-Universität Münster, Münster, Germany
- Institute of Physiology I, Westfälische Wilhelms-Universität, Robert-Koch-Str. 27a, D-48149, Münster, Germany
| | - Louisa Temme
- Institut für Pharmazeutische und Medizinische Chemie, Westfälische Wilhelms-Universität Münster, Corrensstraße 48, D-48149, Münster, Germany
- GRK 2515, Chemical biology of ion channels (Chembion), Westfälische Wilhelms-Universität Münster, Münster, Germany
| | - Timo Strünker
- GRK 2515, Chemical biology of ion channels (Chembion), Westfälische Wilhelms-Universität Münster, Münster, Germany
- Centre of Reproductive Medicine and Andrology, University Hospital Münster, University of Münster, Domagkstraße 11, D-48149, Münster, Germany
- Cells in Motion Interfaculty Centre, University of Münster, Münster, Germany
| | - Birgit Stallmeyer
- Institute of Reproductive Genetics, University of Münster, Vesaliusweg 12-14, D-48149, Münster, Germany
| | - Frank Tüttelmann
- Institute of Reproductive Genetics, University of Münster, Vesaliusweg 12-14, D-48149, Münster, Germany
| | - Sven G Meuth
- Department of Neurology, Heinrich Heine University Düsseldorf, Moorenstraße 5, D-40225, Düsseldorf, Germany
| | - Marc Spehr
- Department of Chemosensation, Institute for Biology II, RWTH Aachen University, Worringerweg 3, D-52074, Aachen, Germany
| | - Johann Matschke
- Institute of Cell Biology (Cancer Research), University Hospital Essen, University of Duisburg-Essen, D-45147, Essen, Germany
| | - Andrea Steinbicker
- Goethe University Frankfurt and University Hospital Frankfurt, Theodor-Stern-Kai 7, D-60590, Frankfurt, Germany
| | - Christos Gatsogiannis
- Institute for Medical Physics and Biophysics and Center for Soft Nanoscience, Westfälische Wilhelms-Universität Münster, Münster, Busso-Peus Strasse 10, D-48149, Germany
| | - Raphael Stoll
- Faculty of Chemistry and Biochemistry, Biomolecular NMR Spectroscopy and RUBiospek|NMR, Ruhr University of Bochum, Universitätsstraße 150, D-44780, Bochum, Germany
| | - Nathalie Strutz-Seebohm
- IfGH-Cellular Electrophysiology, Department of Cardiology and Angiology, University Hospital of Münster, Robert-Koch Str. 45, D-48149, Münster, Germany
| | - Guiscard Seebohm
- IfGH-Cellular Electrophysiology, Department of Cardiology and Angiology, University Hospital of Münster, Robert-Koch Str. 45, D-48149, Münster, Germany
- GRK 2515, Chemical biology of ion channels (Chembion), Westfälische Wilhelms-Universität Münster, Münster, Germany
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Bates A, Stowe RB, Travis EM, Cook LE, Dabney-Smith C, Lorigan GA. The role of native cysteine residues in the oligomerization of KCNQ1 channels. Biochem Biophys Res Commun 2023; 659:34-39. [PMID: 37031592 PMCID: PMC10170711 DOI: 10.1016/j.bbrc.2023.03.082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Accepted: 03/31/2023] [Indexed: 04/03/2023]
Abstract
KCNQ1, the major component of the slow-delayed rectifier potassium channel, is responsible for repolarization of cardiac action potential. Mutations in this channel can lead to a variety of diseases, most notably long QT syndrome. It is currently unknown how many of these mutations change channel function and structure on a molecular level. Since tetramerization is key to proper function and structure of the channel, it is likely that mutations modify the stability of KCNQ1 oligomers. Presently, the C-terminal domain of KCNQ1 has been noted as the driving force for oligomer formation. However, truncated versions of this protein lacking the C-terminal domain still tetramerize. Therefore, we explored the role of native cysteine residues in a truncated construct of human KCNQ1, amino acids 100-370, by blocking potential interactions of cysteines with a nitroxide based spin label. Mobility of the spin labels was investigated with continuous wave electron paramagnetic resonance (CW-EPR) spectroscopy. The oligomerization state was examined by gel electrophoresis. The data provide information on tetramerization of human KCNQ1 without the C-terminal domain. Specifically, how blocking the side chains of native cysteines residues reduces oligomerization. A better understanding of tetramer formation could provide improved understanding of the molecular etiology of long QT syndrome and other diseases related to KCNQ1.
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Affiliation(s)
- Alison Bates
- Department of Chemistry and Biochemistry, Miami University, 651 E. High Street, Oxford, OH, 45056, USA
| | - Rebecca B Stowe
- Department of Chemistry and Biochemistry, Miami University, 651 E. High Street, Oxford, OH, 45056, USA
| | - Elizabeth M Travis
- Department of Chemistry and Biochemistry, Miami University, 651 E. High Street, Oxford, OH, 45056, USA
| | - Lauryn E Cook
- Department of Chemistry and Biochemistry, Miami University, 651 E. High Street, Oxford, OH, 45056, USA
| | - Carole Dabney-Smith
- Department of Chemistry and Biochemistry, Miami University, 651 E. High Street, Oxford, OH, 45056, USA
| | - Gary A Lorigan
- Department of Chemistry and Biochemistry, Miami University, 651 E. High Street, Oxford, OH, 45056, USA.
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Song B, Chen Y, Wang C, Li G, Wei Z, He X, Cao Y. Poor semen parameters are associated with abnormal methylation of imprinted genes in sperm DNA. Reprod Biol Endocrinol 2022; 20:155. [PMID: 36357889 PMCID: PMC9647922 DOI: 10.1186/s12958-022-01028-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Revised: 03/26/2022] [Accepted: 10/26/2022] [Indexed: 11/11/2022] Open
Abstract
BACKGROUND Altered sperm DNA methylation patterns of imprinted genes as well as certain spermatogenesis-related genes has been proposed as a possible mechanism of male subfertility. Some reports suggest that there is an elevated risk of congenital diseases, associated with imprinted genes, in children conceived via intra-cytoplasmic sperm injection, due to the involvement of spermatozoa with aberrant imprinted genes obtained from infertile men. METHODS In this study, the DNA methylation status of the promoter regions of six imprinted genes, namely potassium voltage-gated channel subfamily Q member 1 (KCNQ1), maternally expressed gene 3 (MEG3), insulin-like growth factor 2 (IGF-2), KCNQ1 overlapping transcript 1 (KCNQ1OT1), mesoderm specific transcript (MEST), and paternally expressed gene 3 (PEG3), were detected by a next generation sequencing-based multiple methylation-specific polymerase chain reaction analysis of sperm samples obtained from 166 men who sought fertility evaluation in our Reproductive Medicine Center. Thereafter, the semen samples were classified into subgroups according to sperm motility and DNA integrity status. RESULTS As compared to the normozoospermic group, the samples of the asthenospermic group exhibited significant hypermethylation in two CpG sites of IGF-2 and significant hypomethylation in one CpG site of KCNQ1 as well as three CpG sites of MEST (P < 0.05). However, we did not observe any significant differences in the overall methylation levels of these six imprinted genes (P > 0.05). Additionally, we found that 111 of 323 CpG sites were hypomethylated in the group with DNA fragmentation index (DFI) ≥ 30% as compared to the group with DFI < 30% (P < 0.05). In this case, there were significant differences in the overall methylation levels of MEG3, IGF-2, MEST, and PEG3 (P < 0.05), but not in that of KCNQ1OT1 and KCNQ1 (P > 0.05). Hence, aberrant methylation patterns of imprinted genes were more prevalent in males with poor sperm quality, especially in those with severe sperm DNA damage. CONCLUSION In conclusion, abnormal DNA methylation of some CpG sites of imprinted genes are associated with poor sperm quality, including asthenospermia and severe sperm DNA impairment.
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Affiliation(s)
- Bing Song
- Reproductive Medicine Center, Department of Obstetrics and Gynecology, the First Affiliated Hospital of Anhui Medical University, 230032, Hefei, China
- NHC Key Laboratory of Study on Abnormal Gametes and Reproductive Tract, Anhui Medical University, 230032, Hefei, China
- Ministry of Education Key Laboratory of Population Health Across Life Cycle, Anhui Medical University, 230032, Hefei, China
- Anhui Province Key Laboratory of Reproductive Health and Genetics, 230032, Hefei, China
- Biopreservation and Artificial Organs, Anhui Provincial Engineering Research Center, Anhui Medical University, 230032, Hefei, China
| | - Yujie Chen
- Department of Gynecology and Obstetrics, The Affiliated Wuxi Maternity and Child Health Care Hospital of Nanjing Medical University, 214000, Wuxi, China
| | - Chao Wang
- Reproductive Medicine Center, Department of Obstetrics and Gynecology, the First Affiliated Hospital of Anhui Medical University, 230032, Hefei, China
- NHC Key Laboratory of Study on Abnormal Gametes and Reproductive Tract, Anhui Medical University, 230032, Hefei, China
- Ministry of Education Key Laboratory of Population Health Across Life Cycle, Anhui Medical University, 230032, Hefei, China
- Anhui Province Key Laboratory of Reproductive Health and Genetics, 230032, Hefei, China
- Biopreservation and Artificial Organs, Anhui Provincial Engineering Research Center, Anhui Medical University, 230032, Hefei, China
| | - Guanjian Li
- Reproductive Medicine Center, Department of Obstetrics and Gynecology, the First Affiliated Hospital of Anhui Medical University, 230032, Hefei, China
- NHC Key Laboratory of Study on Abnormal Gametes and Reproductive Tract, Anhui Medical University, 230032, Hefei, China
- Ministry of Education Key Laboratory of Population Health Across Life Cycle, Anhui Medical University, 230032, Hefei, China
- Anhui Province Key Laboratory of Reproductive Health and Genetics, 230032, Hefei, China
- Biopreservation and Artificial Organs, Anhui Provincial Engineering Research Center, Anhui Medical University, 230032, Hefei, China
| | - Zhaolian Wei
- Reproductive Medicine Center, Department of Obstetrics and Gynecology, the First Affiliated Hospital of Anhui Medical University, 230032, Hefei, China
- NHC Key Laboratory of Study on Abnormal Gametes and Reproductive Tract, Anhui Medical University, 230032, Hefei, China
- Ministry of Education Key Laboratory of Population Health Across Life Cycle, Anhui Medical University, 230032, Hefei, China
- Anhui Province Key Laboratory of Reproductive Health and Genetics, 230032, Hefei, China
- Biopreservation and Artificial Organs, Anhui Provincial Engineering Research Center, Anhui Medical University, 230032, Hefei, China
| | - Xiaojin He
- Reproductive Medicine Center, Department of Obstetrics and Gynecology, the First Affiliated Hospital of Anhui Medical University, 230032, Hefei, China.
- NHC Key Laboratory of Study on Abnormal Gametes and Reproductive Tract, Anhui Medical University, 230032, Hefei, China.
- Ministry of Education Key Laboratory of Population Health Across Life Cycle, Anhui Medical University, 230032, Hefei, China.
- Anhui Province Key Laboratory of Reproductive Health and Genetics, 230032, Hefei, China.
- Biopreservation and Artificial Organs, Anhui Provincial Engineering Research Center, Anhui Medical University, 230032, Hefei, China.
| | - Yunxia Cao
- Reproductive Medicine Center, Department of Obstetrics and Gynecology, the First Affiliated Hospital of Anhui Medical University, 230032, Hefei, China.
- NHC Key Laboratory of Study on Abnormal Gametes and Reproductive Tract, Anhui Medical University, 230032, Hefei, China.
- Ministry of Education Key Laboratory of Population Health Across Life Cycle, Anhui Medical University, 230032, Hefei, China.
- Anhui Province Key Laboratory of Reproductive Health and Genetics, 230032, Hefei, China.
- Biopreservation and Artificial Organs, Anhui Provincial Engineering Research Center, Anhui Medical University, 230032, Hefei, China.
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11
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Dixit G, Stowe RB, Bates A, Jaycox CK, Escobar JR, Harding BD, Drew DL, New CP, Sahu ID, Edelmann RE, Dabney-Smith C, Sanders CR, Lorigan GA. Purification and membrane interactions of human KCNQ1 100-370 potassium ion channel. Biochim Biophys Acta Biomembr 2022; 1864:184010. [PMID: 35870481 DOI: 10.1016/j.bbamem.2022.184010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Revised: 07/12/2022] [Accepted: 07/14/2022] [Indexed: 06/15/2023]
Abstract
KCNQ1 (Kv7.1 or KvLQT1) is a voltage-gated potassium ion channel that is involved in the ventricular repolarization following an action potential in the heart. It forms a complex with KCNE1 in the heart and is the pore forming subunit of slow delayed rectifier potassium current (Iks). Mutations in KCNQ1, leading to a dysfunctional channel or loss of activity have been implicated in a cardiac disorder, long QT syndrome. In this study, we report the overexpression, purification, biochemical characterization of human KCNQ1100-370, and lipid bilayer dynamics upon interaction with KCNQ1100-370. The recombinant human KCNQ1 was expressed in Escherichia coli and purified into n-dodecylphosphocholine (DPC) micelles. The purified KCNQ1100-370 was biochemically characterized by SDS-PAGE electrophoresis, western blot and nano-LC-MS/MS to confirm the identity of the protein. Circular dichroism (CD) spectroscopy was utilized to confirm the secondary structure of purified protein in vesicles. Furthermore, 31P and 2H solid-state NMR spectroscopy in DPPC/POPC/POPG vesicles (MLVs) indicated a direct interaction between KCNQ100-370 and the phospholipid head groups. Finally, a visual inspection of KCNQ1100-370 incorporated into MLVs was confirmed by transmission electron microscopy (TEM). The findings of this study provide avenues for future structural studies of the human KCNQ1 ion channel to have an in depth understanding of its structure-function relationship.
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Affiliation(s)
- Gunjan Dixit
- Department of Chemistry and Biochemistry, Miami University, 651 E. High Street, Oxford, OH 45056, USA; Cell, Molecular and Structural Biology Program, Department of Chemistry & Biochemistry, Miami University, Oxford, OH 45056, USA
| | - Rebecca B Stowe
- Department of Chemistry and Biochemistry, Miami University, 651 E. High Street, Oxford, OH 45056, USA
| | - Alison Bates
- Department of Chemistry and Biochemistry, Miami University, 651 E. High Street, Oxford, OH 45056, USA
| | - Colleen K Jaycox
- Department of Chemistry and Biochemistry, Miami University, 651 E. High Street, Oxford, OH 45056, USA
| | - Jorge R Escobar
- Department of Chemistry and Biochemistry, Miami University, 651 E. High Street, Oxford, OH 45056, USA; Cell, Molecular and Structural Biology Program, Department of Chemistry & Biochemistry, Miami University, Oxford, OH 45056, USA
| | - Benjamin D Harding
- Department of Chemistry and Biochemistry, Miami University, 651 E. High Street, Oxford, OH 45056, USA
| | - Daniel L Drew
- Department of Chemistry and Biochemistry, Miami University, 651 E. High Street, Oxford, OH 45056, USA
| | - Christopher P New
- Department of Chemistry and Biochemistry, Miami University, 651 E. High Street, Oxford, OH 45056, USA; Cell, Molecular and Structural Biology Program, Department of Chemistry & Biochemistry, Miami University, Oxford, OH 45056, USA
| | - Indra D Sahu
- Department of Chemistry and Biochemistry, Miami University, 651 E. High Street, Oxford, OH 45056, USA
| | - Richard E Edelmann
- Center for Advanced Microscopy and Imaging, Miami University, Oxford, OH 45056, USA
| | - Carole Dabney-Smith
- Department of Chemistry and Biochemistry, Miami University, 651 E. High Street, Oxford, OH 45056, USA; Cell, Molecular and Structural Biology Program, Department of Chemistry & Biochemistry, Miami University, Oxford, OH 45056, USA
| | - Charles R Sanders
- Department of Biochemistry and Center for Structural Biology, Vanderbilt University, Nashville, TN 37240, USA
| | - Gary A Lorigan
- Department of Chemistry and Biochemistry, Miami University, 651 E. High Street, Oxford, OH 45056, USA; Cell, Molecular and Structural Biology Program, Department of Chemistry & Biochemistry, Miami University, Oxford, OH 45056, USA.
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12
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Campbell C, Faleel FDM, Scheyer MW, Haralu S, Williams PL, Carbo WD, Wilson-Taylor AS, Patel NH, Sanders CR, Lorigan GA, Sahu ID. Comparing the structural dynamics of the human KCNE3 in reconstituted micelle and lipid bilayered vesicle environments. Biochim Biophys Acta Biomembr 2022; 1864:183974. [PMID: 35716725 DOI: 10.1016/j.bbamem.2022.183974] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2021] [Revised: 05/12/2022] [Accepted: 05/25/2022] [Indexed: 06/15/2023]
Abstract
KCNE3 is a single transmembrane protein of the KCNE family that modulates the function and trafficking of several voltage-gated potassium channels, including KCNQ1. Structural studies of KCNE3 have been previously conducted in a wide range of model membrane mimics. However, it is important to assess the impact of the membrane mimics used on the observed conformation and dynamics. In this study, we have optimized a method for the reconstitution of the KCNE3 into POPC/POPG lipid bilayer vesicles for electron paramagnetic resonance (EPR) spectroscopy. Our CD spectroscopic data suggested that the degree of regular secondary structure for KCNE3 protein reconstituted into lipid bilayered vesicle is significantly higher than in DPC detergent micelles. Electron paramagnetic resonance (EPR) spectroscopy in combination with site-directed spin labeling (SDSL) was used to probe the structural dynamics of S49C, M59C, L67C, V85C, and S101C mutations of KCNE3 in both DPC micelles and in POPC/POPG lipid bilayered vesicles. Our CW-EPR power saturation data suggested that the site S74C is buried inside the lipid bilayered membrane while the site V85C is located outside the membrane, in contrast to DPC micelle results. These results suggest that the KCNE3 micelle structures need to be refined using data obtained in the lipid bilayered vesicles in order to ascertain the native structure of KCNE3. This work will provide guidelines for detailed structural studies of KCNE3 in a more native membrane environment and comparing the lipid bilayer results to the isotropic bicelle structure and to the KCNQ1-bound cryo-EM structure.
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Affiliation(s)
- Conner Campbell
- Natural Science Division, Campbellsville University, Campbellsville, KY, United States of America
| | | | - Matthew W Scheyer
- Natural Science Division, Campbellsville University, Campbellsville, KY, United States of America
| | - Samuel Haralu
- Natural Science Division, Campbellsville University, Campbellsville, KY, United States of America
| | - Patrick L Williams
- Natural Science Division, Campbellsville University, Campbellsville, KY, United States of America
| | - William David Carbo
- Natural Science Division, Campbellsville University, Campbellsville, KY, United States of America
| | | | - Nima H Patel
- Natural Science Division, Campbellsville University, Campbellsville, KY, United States of America
| | - Charles R Sanders
- Department of Biochemistry and Center for Structural Biology, Vanderbilt University, Nashville, TN, United States of America
| | - Gary A Lorigan
- Department of Chemistry and Biochemistry, Miami University, Oxford, OH, United States of America
| | - Indra D Sahu
- Natural Science Division, Campbellsville University, Campbellsville, KY, United States of America; Department of Chemistry and Biochemistry, Miami University, Oxford, OH, United States of America.
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13
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Karlova M, Abramochkin DV, Pustovit KB, Nesterova T, Novoseletsky V, Loussouarn G, Zaklyazminskaya E, Sokolova OS. Disruption of a Conservative Motif in the C-Terminal Loop of the KCNQ1 Channel Causes LQT Syndrome. Int J Mol Sci 2022; 23:ijms23147953. [PMID: 35887302 PMCID: PMC9316142 DOI: 10.3390/ijms23147953] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2022] [Revised: 07/13/2022] [Accepted: 07/15/2022] [Indexed: 02/04/2023] Open
Abstract
We identified a single nucleotide variation (SNV) (c.1264A > G) in the KCNQ1 gene in a 5-year-old boy who presented with a prolonged QT interval. His elder brother and mother, but not sister and father, also had this mutation. This missense mutation leads to a p.Lys422Glu (K422E) substitution in the Kv7.1 protein that has never been mentioned before. We inserted this substitution in an expression plasmid containing Kv7.1 cDNA and studied the electrophysiological characteristics of the mutated channel expressed in CHO-K1, using the whole-cell configuration of the patch-clamp technique. Expression of the mutant Kv7.1 channel in both homo- and heterozygous conditions in the presence of auxiliary subunit KCNE1 results in a significant decrease in tail current densities compared to the expression of wild-type (WT) Kv7.1 and KCNE1. This study also indicates that K422E point mutation causes a dominant negative effect. The mutation was not associated with a trafficking defect; the mutant channel protein was confirmed to localize at the cell membrane. This mutation disrupts the poly-Lys strip in the proximal part of the highly conserved cytoplasmic A−B linker of Kv7.1 that was not shown before to be crucial for channel functioning.
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Affiliation(s)
- Maria Karlova
- Faculty of Biology, Lomonosov Moscow State University, 119234 Moscow, Russia; (M.K.); (D.V.A.); (K.B.P.); (V.N.)
| | - Denis V. Abramochkin
- Faculty of Biology, Lomonosov Moscow State University, 119234 Moscow, Russia; (M.K.); (D.V.A.); (K.B.P.); (V.N.)
| | - Ksenia B. Pustovit
- Faculty of Biology, Lomonosov Moscow State University, 119234 Moscow, Russia; (M.K.); (D.V.A.); (K.B.P.); (V.N.)
| | - Tatiana Nesterova
- Institute of Immunology and Physiology, Ural Branch of Russian Academy of Sciences, 620049 Ekaterinburg, Russia;
- Institute of Natural Sciences and Mathematics, Ural Federal University, 620075 Ekaterinburg, Russia
| | - Valery Novoseletsky
- Faculty of Biology, Lomonosov Moscow State University, 119234 Moscow, Russia; (M.K.); (D.V.A.); (K.B.P.); (V.N.)
- Biology Department, Shenzhen MSU-BIT University, Shenzhen 517182, China
| | - Gildas Loussouarn
- Nantes Université, CNRS, INSERM, l’institut du Thorax, F-44000 Nantes, France;
| | | | - Olga S. Sokolova
- Faculty of Biology, Lomonosov Moscow State University, 119234 Moscow, Russia; (M.K.); (D.V.A.); (K.B.P.); (V.N.)
- Biology Department, Shenzhen MSU-BIT University, Shenzhen 517182, China
- Correspondence: or
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14
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Wang Y, Yin C, Zhang H, Kamau PM, Dong W, Luo A, Chai L, Yang S, Lai R. Venom resistance mechanisms in centipede show tissue specificity. Curr Biol 2022; 32:3556-3563.e3. [PMID: 35863353 DOI: 10.1016/j.cub.2022.06.074] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2022] [Revised: 05/16/2022] [Accepted: 06/23/2022] [Indexed: 11/18/2022]
Abstract
Venomous animals utilize venom glands to secrete and store powerful toxins for intraspecific and/or interspecific antagonistic interactions, implying that tissue-specific resistance is essential for venom glands to anatomically separate toxins from other tissues. Here, we show the mechanism of tissue-specific resistance in centipedes (Scolopendra subspinipes mutilans), where the splice variant of the receptor repels its own toxin. Unlike the well-known resistance mechanism by mutation in a given exon, we found that the KCNQ1 channel is highly expressed in the venom gland as a unique splice variant in which the pore domain and transmembrane domain six, partially encoded by exon 6 (rather than 7 as found in other tissues), contain eleven mutated residues. Such a splice variant is sufficient to gain resistance to SsTx (a lethal toxin for giant prey capture) in the venom gland due to a partially buried binding site. Therefore, the tissue-specific KCNQ1 modification confers resistance to the toxins, establishing a safe zone in the venom-storing/secreting environment.
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Affiliation(s)
- Yunfei Wang
- Key Laboratory of Animal Models and Human Disease Mechanisms, Key Laboratory of Bioactive Peptides of Yunnan Province, Engineering Laboratory of Bioactive Peptides, The National & Local Joint Engineering Center of Natural Bioactive Peptides, KIZ-CUHK Joint Laboratory of Bioresources and Molecular Research in Common Diseases, National Resource Center for Non-Human Primates, Kunming Primate Research Center, National Research Facility for Phenotypic & Genetic Analysis of Model Animals (Primate Facility), Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, 650107 Yunnan, China; College of Wildlife and Protected Area, Northeast Forestry University, Harbin 150040, China
| | - Chuanlin Yin
- College of Wildlife and Protected Area, Northeast Forestry University, Harbin 150040, China
| | - Hao Zhang
- Key Laboratory of Animal Models and Human Disease Mechanisms, Key Laboratory of Bioactive Peptides of Yunnan Province, Engineering Laboratory of Bioactive Peptides, The National & Local Joint Engineering Center of Natural Bioactive Peptides, KIZ-CUHK Joint Laboratory of Bioresources and Molecular Research in Common Diseases, National Resource Center for Non-Human Primates, Kunming Primate Research Center, National Research Facility for Phenotypic & Genetic Analysis of Model Animals (Primate Facility), Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, 650107 Yunnan, China; Kunming College of Life Science, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Peter Muiruri Kamau
- Key Laboratory of Animal Models and Human Disease Mechanisms, Key Laboratory of Bioactive Peptides of Yunnan Province, Engineering Laboratory of Bioactive Peptides, The National & Local Joint Engineering Center of Natural Bioactive Peptides, KIZ-CUHK Joint Laboratory of Bioresources and Molecular Research in Common Diseases, National Resource Center for Non-Human Primates, Kunming Primate Research Center, National Research Facility for Phenotypic & Genetic Analysis of Model Animals (Primate Facility), Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, 650107 Yunnan, China; Kunming College of Life Science, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Wenqi Dong
- College of Wildlife and Protected Area, Northeast Forestry University, Harbin 150040, China
| | - Anna Luo
- Key Laboratory of Animal Models and Human Disease Mechanisms, Key Laboratory of Bioactive Peptides of Yunnan Province, Engineering Laboratory of Bioactive Peptides, The National & Local Joint Engineering Center of Natural Bioactive Peptides, KIZ-CUHK Joint Laboratory of Bioresources and Molecular Research in Common Diseases, National Resource Center for Non-Human Primates, Kunming Primate Research Center, National Research Facility for Phenotypic & Genetic Analysis of Model Animals (Primate Facility), Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, 650107 Yunnan, China; Kunming College of Life Science, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Longhui Chai
- College of Wildlife and Protected Area, Northeast Forestry University, Harbin 150040, China
| | - Shilong Yang
- College of Wildlife and Protected Area, Northeast Forestry University, Harbin 150040, China.
| | - Ren Lai
- Key Laboratory of Animal Models and Human Disease Mechanisms, Key Laboratory of Bioactive Peptides of Yunnan Province, Engineering Laboratory of Bioactive Peptides, The National & Local Joint Engineering Center of Natural Bioactive Peptides, KIZ-CUHK Joint Laboratory of Bioresources and Molecular Research in Common Diseases, National Resource Center for Non-Human Primates, Kunming Primate Research Center, National Research Facility for Phenotypic & Genetic Analysis of Model Animals (Primate Facility), Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, 650107 Yunnan, China; Kunming College of Life Science, University of Chinese Academy of Sciences, Beijing 100049, China; Sino-African Joint Research Center, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan 650223, China.
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15
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Haverinen J, Hassinen M, Vornanen M. Effect of Channel Assembly (KCNQ1 or KCNQ1 + KCNE1) on the Response of Zebrafish IKs Current to IKs Inhibitors and Activators. J Cardiovasc Pharmacol 2022; 79:670-677. [PMID: 35377576 DOI: 10.1097/fjc.0000000000001230] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Accepted: 01/15/2022] [Indexed: 11/26/2022]
Abstract
ABSTRACT In cardiac myocytes, the slow component of the delayed rectifier K+ current (IKs) ensures repolarization of action potential during beta-adrenergic activation or when other repolarizing K+ currents fail. As a key factor of cardiac repolarization, IKs should be present in model species used for cardiovascular drug screening, preferably with pharmacological characteristics similar to those of the human IKs. To this end, we investigated the effects of inhibitors and activators of the IKs on KCNQ1 and KCNQ1 + KCNE1 channels of the zebrafish, an important model species, in Chinese hamster ovary cells. Inhibitors of IKs, chromanol 293B and HMR-1556, inhibited zebrafish IKs channels with approximately similar potency as that of mammalian IKs. Chromanol 293B concentration for half-maximal inhibition (IC50) of zebrafish IKs was at 13.1 ± 5.8 and 13.4 ± 2.8 µM for KCNQ1 and KCNQ1+KCNE1 channels, respectively. HMR-1556 was a more potent inhibitor of zebrafish IKs channels with IC50 = 0.1 ± 0.1 µM and 1.5 ± 0.8 µM for KCNQ1 and KCNQ1 + KCNE1 channels, respectively. R-L3 and mefenamic acid, generally identified as IKs activators, both inhibited zebrafish IKs. R-L3 almost completely inhibited the current generated by KCNQ1 and KCNQ1 + KCNE1 channels with similar potency (IC50 1.1 ± 0.4 and 1.0 ± 0.4 µM, respectively). Mefenamic acid partially blocked zebrafish KCNQ1 (IC50 = 9.5 ± 4.8 µM) and completely blocked KCNQ1 + KCNE1 channels (IC50 = 3.3 ± 1.8 µM). Although zebrafish IKs channels respond to IKs inhibitors in the same way as mammalian IKs channels, their response to activators is atypical, probably because of the differences in the binding domain of KCNE1 to KCNQ1. Therefore, care must be taken when translating the results from zebrafish to humans.
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Affiliation(s)
- Jaakko Haverinen
- Department of Environmental and Biological Sciences, University of Eastern Finland, Joensuu, Finland
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16
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Cócera-Ortega L, Wilders R, Kamps SC, Fabrizi B, Huber I, van der Made I, van den Bout A, de Vries DK, Gepstein L, Verkerk AO, Pinto YM, Tijsen AJ. shRNAs Targeting a Common KCNQ1 Variant Could Alleviate Long-QT1 Disease Severity by Inhibiting a Mutant Allele. Int J Mol Sci 2022; 23:ijms23074053. [PMID: 35409410 PMCID: PMC9000197 DOI: 10.3390/ijms23074053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Revised: 03/31/2022] [Accepted: 04/04/2022] [Indexed: 12/02/2022] Open
Abstract
Long-QT syndrome type 1 (LQT1) is caused by mutations in KCNQ1. Patients heterozygous for such a mutation co-assemble both mutant and wild-type KCNQ1-encoded subunits into tetrameric Kv7.1 potassium channels. Here, we investigated whether allele-specific inhibition of mutant KCNQ1 by targeting a common variant can shift the balance towards increased incorporation of the wild-type allele to alleviate the disease in human-induced pluripotent stem-cell-derived cardiomyocytes (hiPSC-CMs). We identified the single nucleotide polymorphisms (SNP) rs1057128 (G/A) in KCNQ1, with a heterozygosity of 27% in the European population. Next, we determined allele-specificity of short-hairpin RNAs (shRNAs) targeting either allele of this SNP in hiPSC-CMs that carry an LQT1 mutation. Our shRNAs downregulated 60% of the A allele and 40% of the G allele without affecting the non-targeted allele. Suppression of the mutant KCNQ1 allele by 60% decreased the occurrence of arrhythmic events in hiPSC-CMs measured by a voltage-sensitive reporter, while suppression of the wild-type allele increased the occurrence of arrhythmic events. Furthermore, computer simulations based on another LQT1 mutation revealed that 60% suppression of the mutant KCNQ1 allele shortens the prolonged action potential in an adult cardiomyocyte model. We conclude that allele-specific inhibition of a mutant KCNQ1 allele by targeting a common variant may alleviate the disease. This novel approach avoids the need to design shRNAs to target every single mutation and opens up the exciting possibility of treating multiple LQT1-causing mutations with only two shRNAs.
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Affiliation(s)
- Lucía Cócera-Ortega
- Department of Experimental Cardiology, Amsterdam Cardiovascular Sciences, Amsterdam UMC, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands; (L.C.-O.); (S.C.K.); (B.F.); (I.v.d.M.); (A.v.d.B.); (D.K.d.V.); (A.O.V.); (Y.M.P.)
| | - Ronald Wilders
- Department of Medical Biology, Amsterdam Cardiovascular Sciences, Amsterdam UMC, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands;
| | - Selina C. Kamps
- Department of Experimental Cardiology, Amsterdam Cardiovascular Sciences, Amsterdam UMC, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands; (L.C.-O.); (S.C.K.); (B.F.); (I.v.d.M.); (A.v.d.B.); (D.K.d.V.); (A.O.V.); (Y.M.P.)
| | - Benedetta Fabrizi
- Department of Experimental Cardiology, Amsterdam Cardiovascular Sciences, Amsterdam UMC, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands; (L.C.-O.); (S.C.K.); (B.F.); (I.v.d.M.); (A.v.d.B.); (D.K.d.V.); (A.O.V.); (Y.M.P.)
| | - Irit Huber
- The Sohnis Family Laboratory for Cardiac Electrophysiology and Regenerative Medicine, Rappaport Faculty of Medicine and Research Institute, Technion—Israel Institute of Technology, Haifa 3109601, Israel; (I.H.); (L.G.)
| | - Ingeborg van der Made
- Department of Experimental Cardiology, Amsterdam Cardiovascular Sciences, Amsterdam UMC, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands; (L.C.-O.); (S.C.K.); (B.F.); (I.v.d.M.); (A.v.d.B.); (D.K.d.V.); (A.O.V.); (Y.M.P.)
| | - Anouk van den Bout
- Department of Experimental Cardiology, Amsterdam Cardiovascular Sciences, Amsterdam UMC, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands; (L.C.-O.); (S.C.K.); (B.F.); (I.v.d.M.); (A.v.d.B.); (D.K.d.V.); (A.O.V.); (Y.M.P.)
| | - Dylan K. de Vries
- Department of Experimental Cardiology, Amsterdam Cardiovascular Sciences, Amsterdam UMC, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands; (L.C.-O.); (S.C.K.); (B.F.); (I.v.d.M.); (A.v.d.B.); (D.K.d.V.); (A.O.V.); (Y.M.P.)
| | - Lior Gepstein
- The Sohnis Family Laboratory for Cardiac Electrophysiology and Regenerative Medicine, Rappaport Faculty of Medicine and Research Institute, Technion—Israel Institute of Technology, Haifa 3109601, Israel; (I.H.); (L.G.)
| | - Arie O. Verkerk
- Department of Experimental Cardiology, Amsterdam Cardiovascular Sciences, Amsterdam UMC, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands; (L.C.-O.); (S.C.K.); (B.F.); (I.v.d.M.); (A.v.d.B.); (D.K.d.V.); (A.O.V.); (Y.M.P.)
- Department of Medical Biology, Amsterdam Cardiovascular Sciences, Amsterdam UMC, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands;
| | - Yigal M. Pinto
- Department of Experimental Cardiology, Amsterdam Cardiovascular Sciences, Amsterdam UMC, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands; (L.C.-O.); (S.C.K.); (B.F.); (I.v.d.M.); (A.v.d.B.); (D.K.d.V.); (A.O.V.); (Y.M.P.)
| | - Anke J. Tijsen
- Department of Experimental Cardiology, Amsterdam Cardiovascular Sciences, Amsterdam UMC, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands; (L.C.-O.); (S.C.K.); (B.F.); (I.v.d.M.); (A.v.d.B.); (D.K.d.V.); (A.O.V.); (Y.M.P.)
- Correspondence: ; Tel.: +31-205668544
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17
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Di S, Han L, An X, Kong R, Gao Z, Yang Y, Wang X, Zhang P, Ding Q, Wu H, Wang H, Zhao L, Tong X. In silico network pharmacology and in vivo analysis of berberine-related mechanisms against type 2 diabetes mellitus and its complications. J Ethnopharmacol 2021; 276:114180. [PMID: 33957209 DOI: 10.1016/j.jep.2021.114180] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Revised: 04/24/2021] [Accepted: 04/28/2021] [Indexed: 06/12/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Berberine (BBR), extracted from the traditional medicinal plant Coptis chinensis Franch., has been widely used for the treatment of type 2 diabetes mellitus (T2DM) and its complications. AIM OF THE STUDY To determine the potential pharmacological mechanisms underlying BBR therapeutic effect on T2DM and its complications by in silico network pharmacology and experimental in vivo validation. MATERIALS AND METHODS A predictive network depicting the relationship between BBR and T2DM was designed based on information collected from several databases, namely STITCH, CHEMBL, PharmMapper, TTD, Drugbank, and PharmGKB. Identified overlapping targets related to both BBR and T2DM were crossed with information on biological processes (BPs) and molecular/signaling pathways using the DAVID platform and Cytoscape software. Three candidate targets identified with the BBR-T2DM network (RXRA, KCNQ1 and NR3C1) were evaluated in the C57BL/6J mouse model of T2DM. The mice were treated with BBR or metformin for 10 weeks. Weight, fasting blood glucose (FBG), oral glucose tolerance, and expression levels of the three targets were evaluated. RESULTS A total of 31 targets of BBR that were also related to T2DM were identified, of which 14 had already been reported in previous studies. Furthermore, these 31 overlapping targets were enriched in 21 related BPs and 18 pathways involved in T2DM treatment. The identified BP-target-pathway network revealed the underlying mechanisms of BBR antidiabetic activity were mediated by core targets such as RXRA, KCNQ1, and NR3C1. In vivo experiments further confirmed that treatment with BBR significantly reduced weight and FBG and alleviated insulin resistance in T2DM mice. Moreover, BBR treatment promoted RXRA expression, whereas it reduced KCNQ1 and NR3C1 expression in the liver. CONCLUSION Using network pharmacology and a T2DM mouse model, this study revealed that BBR can effectively prevent T2DM symptoms through vital targets and multiple signaling pathways. Network pharmacology provides an efficient, time-saving approach for therapeutic research and the development of new drugs.
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Affiliation(s)
- Sha Di
- Department of Endocrinology, Guang'anmen Hospital of China, Academy of Chinese Medical Sciences, Beijing, 100053, China.
| | - Lin Han
- Department of Endocrinology, Guang'anmen Hospital of China, Academy of Chinese Medical Sciences, Beijing, 100053, China; Laboratory of Molecular and Biology, Guang'anmen Hospital of China, Academy of Chinese Medical Sciences, Beijing, 100053, China.
| | - Xuedong An
- Department of Endocrinology, Guang'anmen Hospital of China, Academy of Chinese Medical Sciences, Beijing, 100053, China.
| | - Ran Kong
- State Key Laboratory of Proteomics, Beijing Proteome Research Center, National Center for Protein Sciences (Beijing), Beijing Institute of Lifeomics, Beijing, 102206, China.
| | - Zezheng Gao
- Department of Endocrinology, Guang'anmen Hospital of China, Academy of Chinese Medical Sciences, Beijing, 100053, China.
| | - Yingying Yang
- Department of Endocrinology, Guang'anmen Hospital of China, Academy of Chinese Medical Sciences, Beijing, 100053, China.
| | - Xinmiao Wang
- Department of Endocrinology, Guang'anmen Hospital of China, Academy of Chinese Medical Sciences, Beijing, 100053, China; Endocrinology Department, Affiliated Hospital to Changchun University of Chinese Medicine, Changchun, Jilin, China.
| | - Pei Zhang
- Department of Endocrinology, Guang'anmen Hospital of China, Academy of Chinese Medical Sciences, Beijing, 100053, China.
| | - Qiyou Ding
- Department of Endocrinology, Guang'anmen Hospital of China, Academy of Chinese Medical Sciences, Beijing, 100053, China.
| | - Haoran Wu
- Department of Endocrinology, Guang'anmen Hospital of China, Academy of Chinese Medical Sciences, Beijing, 100053, China.
| | - Han Wang
- Department of Endocrinology, Guang'anmen Hospital of China, Academy of Chinese Medical Sciences, Beijing, 100053, China.
| | - Linhua Zhao
- Department of Endocrinology, Guang'anmen Hospital of China, Academy of Chinese Medical Sciences, Beijing, 100053, China; Endocrinology Department, Affiliated Hospital to Changchun University of Chinese Medicine, Changchun, Jilin, China.
| | - Xiaolin Tong
- Endocrinology Department, Affiliated Hospital to Changchun University of Chinese Medicine, Changchun, Jilin, China.
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18
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Abstract
The delayed rectifier potassium IKs channel is an important regulator of the duration of the ventricular action potential. Hundreds of mutations in the genes (KCNQ1 and KCNE1) encoding the IKs channel cause long QT syndrome (LQTS). LQTS is a heart disorder that can lead to severe cardiac arrhythmias and sudden cardiac death. A better understanding of the IKs channel (here called the KCNQ1/KCNE1 channel) properties and activities is of great importance to find the causes of LQTS and thus potentially treat LQTS. The KCNQ1/KCNE1 channel belongs to the superfamily of voltage-gated potassium channels. The KCNQ1/KCNE1 channel consists of both the pore-forming subunit KCNQ1 and the modulatory subunit KCNE1. KCNE1 regulates the function of the KCNQ1 channel in several ways. This review aims to describe the current structural and functional knowledge about the cardiac KCNQ1/KCNE1 channel. In addition, we focus on the modulation of the KCNQ1/KCNE1 channel and its potential as a target therapeutic of LQTS.
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19
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Xu Parks X, Qudsi H, Braun C, Lopes CMB. The auxiliary subunit KCNE1 regulates KCNQ1 channel response to sustained calcium-dependent PKC activation. PLoS One 2020; 15:e0237591. [PMID: 32833978 PMCID: PMC7446858 DOI: 10.1371/journal.pone.0237591] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Accepted: 07/29/2020] [Indexed: 11/18/2022] Open
Abstract
The slow cardiac delayed rectifier current (IKs) is formed by KCNQ1 and KCNE1 subunits and is one of the major repolarizing currents in the heart. Decrease of IKs currents either due to inherited mutations or pathological remodeling is associated with increased risk for cardiac arrhythmias and sudden death. Ca2+-dependent PKC isoforms (cPKC) are chronically activated in heart disease and diabetes. Recently, we found that sustained stimulation of the calcium-dependent PKCβII isoform leads to decrease in KCNQ1 subunit membrane localization and KCNQ1/KCNE1 channel activity, although the role of KCNE1 in this regulation was not explored. Here, we show that the auxiliary KCNE1 subunit expression is necessary for channel internalization. A mutation in a KCNE1 phosphorylation site (KCNE1(S102A)) abolished channel internalization in both heterologous expression systems and cardiomyocytes. Altogether, our results suggest that KCNE1(S102) phosphorylation by PKCβII leads to KCNQ1/KCNE1 channel internalization in response to sustained PKC stimulus, while leaving KCNQ1 homomeric channels in the membrane. This preferential internalization is expected to have strong impact on cardiac repolarization. Our results suggest that KCNE1(S102) is an important anti-arrhythmic drug target to prevent IKs pathological remodeling leading to cardiac arrhythmias.
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Affiliation(s)
- Xiaorong Xu Parks
- Aab Cardiovascular Research Institute, Department of Medicine, University of Rochester School of Medicine and Dentistry, Rochester, NY, United States of America
| | - Haani Qudsi
- Aab Cardiovascular Research Institute, Department of Medicine, University of Rochester School of Medicine and Dentistry, Rochester, NY, United States of America
| | - Chen Braun
- Aab Cardiovascular Research Institute, Department of Medicine, University of Rochester School of Medicine and Dentistry, Rochester, NY, United States of America
| | - Coeli M. B. Lopes
- Aab Cardiovascular Research Institute, Department of Medicine, University of Rochester School of Medicine and Dentistry, Rochester, NY, United States of America
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20
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Serrano-Novillo C, Oliveras A, Ferreres JC, Condom E, Felipe A. Remodeling of Kv7.1 and Kv7.5 Expression in Vascular Tumors. Int J Mol Sci 2020; 21:ijms21176019. [PMID: 32825637 PMCID: PMC7503939 DOI: 10.3390/ijms21176019] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Revised: 08/11/2020] [Accepted: 08/18/2020] [Indexed: 12/16/2022] Open
Abstract
Voltage-dependent potassium (Kv) channels contribute to the excitability of nerves and muscles. In addition, Kv participates in several cell functions, including cell cycle progression and proliferation. Kv channel remodeling has been associated with neoplastic cell growth and cancer. Kv7 channels are expressed in blood vessels, and they participate in the maintenance of vascular tone and are implicated in myocyte proliferation. Although evidence links Kv7 remodeling to different types of cancer, its expression in vascular tumors has never been studied. Endothelium-derived vascular neoplasms range from indolent lesions to highly aggressive and metastasizing cancers. Here, we show that Kv7.1 and Kv7.5 are evenly distributed in tunicas as well as the endothelium of healthy veins and arteries. The layered structure of vessels is lost in vascular tumors. By studying eight vascular tumors with different origins and characteristics, we found that Kv7.1 and Kv7.5 expression was changed in vascular cancers. While both channels were generally downregulated, Kv7.5 expression was clearly correlated with neoplastic malignancy. The vascular tumors did not contract; therefore, the role of Kv7 channels is probably related to proliferation rather than controlling vascular tone. Our results identify vascular Kv7 channels as targets for cancer detection and anticancer therapies.
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Affiliation(s)
- Clara Serrano-Novillo
- Molecular Physiology Laboratory, Department de Bioquímica i Biomedicina Molecular, Institut de Biomedicina (IBUB), Universitat de Barcelona, 08028 Barcelona, Spain; (C.S.-N.); (A.O.)
| | - Anna Oliveras
- Molecular Physiology Laboratory, Department de Bioquímica i Biomedicina Molecular, Institut de Biomedicina (IBUB), Universitat de Barcelona, 08028 Barcelona, Spain; (C.S.-N.); (A.O.)
| | - Joan Carles Ferreres
- Consorci Corporació Sanitària Parc Taulí-Parc Taulí Hospital Universitari, Universitat Autónoma de Barcelona, 08208 Sabadell, Spain;
| | - Enric Condom
- Institut d’Investigació Biomèdica de Bellvitge (IDIBELL), Hospital Universitari de Bellvitge, 08907 L’Hospitalet de Llobregat, Spain;
| | - Antonio Felipe
- Molecular Physiology Laboratory, Department de Bioquímica i Biomedicina Molecular, Institut de Biomedicina (IBUB), Universitat de Barcelona, 08028 Barcelona, Spain; (C.S.-N.); (A.O.)
- Departament de Bioquímica i Biomedicina Molecular, Universitat de Barcelona, Avda. Diagonal 643, 08028 Barcelona, Spain
- Correspondence: ; Tel.: +34-934034616; Fax: +34-934021559
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21
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Oliveras A, Serrano-Novillo C, Moreno C, de la Cruz A, Valenzuela C, Soeller C, Comes N, Felipe A. The unconventional biogenesis of Kv7.1-KCNE1 complexes. Sci Adv 2020; 6:eaay4472. [PMID: 32270035 PMCID: PMC7112945 DOI: 10.1126/sciadv.aay4472] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Accepted: 01/09/2020] [Indexed: 06/11/2023]
Abstract
The potassium channel Kv7.1 associates with the KCNE1 regulatory subunit to trigger cardiac I Ks currents. Although the Kv7.1/KCNE1 complex has received much attention, the subcellular compartment hosting the assembly is the subject of ongoing debate. Evidence suggests that the complex forms either earlier in the endoplasmic reticulum or directly at the plasma membrane. Kv7.1 and KCNE1 mutations, responsible for long QT syndromes, impair association and traffic, thereby altering I Ks currents. We found that Kv7.1 and KCNE1 do not assemble in the first stages of their biogenesis. Data support an unconventional secretory pathway for Kv7.1-KCNE1 that bypasses Golgi. This route targets channels to endoplasmic reticulum-plasma membrane junctions, where Kv7.1-KCNE1 assemble. This mechanism helps to resolve the ongoing controversy about the subcellular compartment hosting the association. Our results also provide new insights into I Ks channel localization at endoplasmic reticulum-plasma membrane junctions, highlighting an alternative anterograde trafficking mechanism for oligomeric ion channels.
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Affiliation(s)
- Anna Oliveras
- Molecular Physiology Laboratory, Departamento de Bioquímica i Biomedicina Molecular, Institut de Biomedicina (IBUB), Universitat de Barcelona, Barcelona, Spain
| | - Clara Serrano-Novillo
- Molecular Physiology Laboratory, Departamento de Bioquímica i Biomedicina Molecular, Institut de Biomedicina (IBUB), Universitat de Barcelona, Barcelona, Spain
| | - Cristina Moreno
- National Institute of Neurological Disorders and Stroke (NIH), Bethesda, MD, USA
| | - Alicia de la Cruz
- Instituto de Investigaciones Biomédicas Alberto Sols CSIC-UAM, Madrid, Spain
| | - Carmen Valenzuela
- Instituto de Investigaciones Biomédicas Alberto Sols CSIC-UAM, Madrid, Spain
- Spanish Network for Biomedical Research in Cardiovascular Research (CIBERCV), Instituto de Salud Carlos III, Madrid, Spain
| | - Christian Soeller
- Living Systems Institute and Biomedical Physics, University of Exeter, Exeter, UK
| | - Núria Comes
- Departamento De Biomedicina, Institut d’Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Universitat de Barcelona, Barcelona, Spain
| | - Antonio Felipe
- Molecular Physiology Laboratory, Departamento de Bioquímica i Biomedicina Molecular, Institut de Biomedicina (IBUB), Universitat de Barcelona, Barcelona, Spain
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22
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Taylor KC, Kang PW, Hou P, Yang ND, Kuenze G, Smith JA, Shi J, Huang H, White KM, Peng D, George AL, Meiler J, McFeeters RL, Cui J, Sanders CR. Structure and physiological function of the human KCNQ1 channel voltage sensor intermediate state. eLife 2020; 9:e53901. [PMID: 32096762 PMCID: PMC7069725 DOI: 10.7554/elife.53901] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2019] [Accepted: 02/24/2020] [Indexed: 12/14/2022] Open
Abstract
Voltage-gated ion channels feature voltage sensor domains (VSDs) that exist in three distinct conformations during activation: resting, intermediate, and activated. Experimental determination of the structure of a potassium channel VSD in the intermediate state has previously proven elusive. Here, we report and validate the experimental three-dimensional structure of the human KCNQ1 voltage-gated potassium channel VSD in the intermediate state. We also used mutagenesis and electrophysiology in Xenopus laevisoocytes to functionally map the determinants of S4 helix motion during voltage-dependent transition from the intermediate to the activated state. Finally, the physiological relevance of the intermediate state KCNQ1 conductance is demonstrated using voltage-clamp fluorometry. This work illuminates the structure of the VSD intermediate state and demonstrates that intermediate state conductivity contributes to the unusual versatility of KCNQ1, which can function either as the slow delayed rectifier current (IKs) of the cardiac action potential or as a constitutively active epithelial leak current.
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Affiliation(s)
- Keenan C Taylor
- Department of Biochemistry, Vanderbilt UniversityNashvilleUnited States
- Center for Structural Biology, Vanderbilt UniversityNashvilleUnited States
| | - Po Wei Kang
- Department of Biomedical Engineering, Center for the Investigation of Membrane Excitability Disorders, and Cardiac Bioelectricity, and Arrhythmia Center, Washington University in St. LouisSt. LouisUnited States
| | - Panpan Hou
- Department of Biomedical Engineering, Center for the Investigation of Membrane Excitability Disorders, and Cardiac Bioelectricity, and Arrhythmia Center, Washington University in St. LouisSt. LouisUnited States
| | - Nien-Du Yang
- Department of Biomedical Engineering, Center for the Investigation of Membrane Excitability Disorders, and Cardiac Bioelectricity, and Arrhythmia Center, Washington University in St. LouisSt. LouisUnited States
| | - Georg Kuenze
- Center for Structural Biology, Vanderbilt UniversityNashvilleUnited States
- Departments of Chemistry and Pharmacology, Vanderbilt UniversityNashvilleUnited States
| | - Jarrod A Smith
- Department of Biochemistry, Vanderbilt UniversityNashvilleUnited States
- Center for Structural Biology, Vanderbilt UniversityNashvilleUnited States
| | - Jingyi Shi
- Department of Biomedical Engineering, Center for the Investigation of Membrane Excitability Disorders, and Cardiac Bioelectricity, and Arrhythmia Center, Washington University in St. LouisSt. LouisUnited States
| | - Hui Huang
- Department of Biochemistry, Vanderbilt UniversityNashvilleUnited States
- Center for Structural Biology, Vanderbilt UniversityNashvilleUnited States
| | - Kelli McFarland White
- Department of Biomedical Engineering, Center for the Investigation of Membrane Excitability Disorders, and Cardiac Bioelectricity, and Arrhythmia Center, Washington University in St. LouisSt. LouisUnited States
| | - Dungeng Peng
- Department of Biochemistry, Vanderbilt UniversityNashvilleUnited States
- Center for Structural Biology, Vanderbilt UniversityNashvilleUnited States
- Department of Medicine, Division of Clinical Pharmacology, Vanderbilt University Medical CenterNashvilleUnited States
| | - Alfred L George
- Department of Pharmacology, Northwestern University Feinberg School of MedicineChicagoUnited States
| | - Jens Meiler
- Center for Structural Biology, Vanderbilt UniversityNashvilleUnited States
- Departments of Chemistry and Pharmacology, Vanderbilt UniversityNashvilleUnited States
- Department of Bioinformatics, Vanderbilt University Medical CenterNashvilleUnited States
| | - Robert L McFeeters
- Department of Chemistry, University of Alabama in HuntsvilleHuntsvilleUnited States
| | - Jianmin Cui
- Department of Biomedical Engineering, Center for the Investigation of Membrane Excitability Disorders, and Cardiac Bioelectricity, and Arrhythmia Center, Washington University in St. LouisSt. LouisUnited States
| | - Charles R Sanders
- Department of Biochemistry, Vanderbilt UniversityNashvilleUnited States
- Center for Structural Biology, Vanderbilt UniversityNashvilleUnited States
- Department of Medicine, Vanderbilt University Medical CenterNashvilleUnited States
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23
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Hynes D, Harvey BJ. Dexamethasone reduces airway epithelial Cl - secretion by rapid non-genomic inhibition of KCNQ1, KCNN4 and KATP K + channels. Steroids 2019; 151:108459. [PMID: 31330137 DOI: 10.1016/j.steroids.2019.108459] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Revised: 07/05/2019] [Accepted: 07/07/2019] [Indexed: 11/26/2022]
Abstract
Basolateral membrane K+ channels play a key role in basal and agonist stimulated Cl- transport across airway epithelial cells by generating a favourable electrical driving force for Cl- efflux. The K+ channel sub-types and molecular mechanisms of regulation by hormones and secretagoues are still poorly understood. Here we have identified the type of K+ channels involved in cAMP and Ca2+ stimulated Cl- secretion and uncovered a novel anti-secretory effect of dexamethasone mediated by inhibition of basolateral membrane K+ channels in a human airway cell model of 16HBE14o- cells commonly used for ion transport studies. Dexamethasone produced a rapid inhibition of transepithelial chloride ion secretion under steady state conditions and after stimulation with cAMP agonist (forskolin) or a Ca2+ mobilizing agonist (ATP). Our results show three different types of K+ channels are targeted by dexamethasone to reduce airway secretion, namely Ca2+-activated secretion via KCNN4 (KCa3.1) channels and cAMP-activated secretion via KCNQ1 (Kv7.1) and KATP (Kir6.1,6.2) channels. The down-regulation of KCNN4 and KCNQ1 channel activities by dexamethasone involves rapid non-genomic activation of PKCα and PKA signalling pathways, respectively. Dexamethasone signal transduction for PKC and PKA activation was demonstrated to occur through a rapid non-genomic pathway that did not implicate the classical nuclear receptors for glucocorticoids or mineralocorticoids but occurred via a novel signalling cascade involving sequentially a Gi-protein coupled receptor, PKC, adenylyl cyclase Type IV, cAMP, PKA and ERK1/2 activation. The rapid, non-genomic, effects of dexamethasone on airway epithelial ion transport and cell signalling introduces a new paradigm for glucocorticoid actions in lung epithelia which may serve to augment the anti-inflammatory activity of the steroid and enhance its therapeutic potential in treating airway hypersecretion in asthma and COPD.
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Affiliation(s)
- Darina Hynes
- Department of Molecular Medicine, Royal College of Surgeons in Ireland, Beaumont Hospital, Dublin 9, Ireland
| | - Brian J Harvey
- Department of Molecular Medicine, Royal College of Surgeons in Ireland, Beaumont Hospital, Dublin 9, Ireland; Centro di Estudios Cientificos CECs, Valdivia, Chile.
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24
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Kuenze G, Duran AM, Woods H, Brewer KR, McDonald EF, Vanoye CG, George AL, Sanders CR, Meiler J. Upgraded molecular models of the human KCNQ1 potassium channel. PLoS One 2019; 14:e0220415. [PMID: 31518351 PMCID: PMC6743773 DOI: 10.1371/journal.pone.0220415] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Accepted: 07/15/2019] [Indexed: 11/29/2022] Open
Abstract
The voltage-gated potassium channel KCNQ1 (KV7.1) assembles with the KCNE1 accessory protein to generate the slow delayed rectifier current, IKS, which is critical for membrane repolarization as part of the cardiac action potential. Loss-of-function (LOF) mutations in KCNQ1 are the most common cause of congenital long QT syndrome (LQTS), type 1 LQTS, an inherited genetic predisposition to cardiac arrhythmia and sudden cardiac death. A detailed structural understanding of KCNQ1 is needed to elucidate the molecular basis for KCNQ1 LOF in disease and to enable structure-guided design of new anti-arrhythmic drugs. In this work, advanced structural models of human KCNQ1 in the resting/closed and activated/open states were developed by Rosetta homology modeling guided by newly available experimentally-based templates: X. leavis KCNQ1 and various resting voltage sensor structures. Using molecular dynamics (MD) simulations, the capacity of the models to describe experimentally established channel properties including state-dependent voltage sensor gating charge interactions and pore conformations, PIP2 binding sites, and voltage sensor–pore domain interactions were validated. Rosetta energy calculations were applied to assess the utility of each model in interpreting mutation-evoked KCNQ1 dysfunction by predicting the change in protein thermodynamic stability for 50 experimentally characterized KCNQ1 variants with mutations located in the voltage-sensing domain. Energetic destabilization was successfully predicted for folding-defective KCNQ1 LOF mutants whereas wild type-like mutants exhibited no significant energetic frustrations, which supports growing evidence that mutation-induced protein destabilization is an especially common cause of KCNQ1 dysfunction. The new KCNQ1 Rosetta models provide helpful tools in the study of the structural basis for KCNQ1 function and can be used to generate hypotheses to explain KCNQ1 dysfunction.
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Affiliation(s)
- Georg Kuenze
- Center for Structural Biology, Vanderbilt University, Nashville, Tennessee, United States of America
- Department of Chemistry, Vanderbilt University, Nashville, Tennessee, United States of America
| | - Amanda M. Duran
- Center for Structural Biology, Vanderbilt University, Nashville, Tennessee, United States of America
- Department of Chemistry, Vanderbilt University, Nashville, Tennessee, United States of America
| | - Hope Woods
- Center for Structural Biology, Vanderbilt University, Nashville, Tennessee, United States of America
- Department of Chemistry, Vanderbilt University, Nashville, Tennessee, United States of America
| | - Kathryn R. Brewer
- Center for Structural Biology, Vanderbilt University, Nashville, Tennessee, United States of America
- Department of Biochemistry, Vanderbilt University, Nashville, Tennessee, United States of America
| | - Eli Fritz McDonald
- Center for Structural Biology, Vanderbilt University, Nashville, Tennessee, United States of America
- Department of Chemistry, Vanderbilt University, Nashville, Tennessee, United States of America
| | - Carlos G. Vanoye
- Department of Pharmacology, Northwestern University Feinberg School of Medicine, Chicago, Illinois, United States of America
| | - Alfred L. George
- Department of Pharmacology, Northwestern University Feinberg School of Medicine, Chicago, Illinois, United States of America
| | - Charles R. Sanders
- Center for Structural Biology, Vanderbilt University, Nashville, Tennessee, United States of America
- Department of Biochemistry, Vanderbilt University, Nashville, Tennessee, United States of America
| | - Jens Meiler
- Center for Structural Biology, Vanderbilt University, Nashville, Tennessee, United States of America
- Department of Chemistry, Vanderbilt University, Nashville, Tennessee, United States of America
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee, United States of America
- * E-mail:
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25
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Li Y, Hof T, Baldwin TA, Chen L, Kass RS, Dessauer CW. Regulation of I Ks Potassium Current by Isoproterenol in Adult Cardiomyocytes Requires Type 9 Adenylyl Cyclase. Cells 2019; 8:cells8090981. [PMID: 31461851 PMCID: PMC6770663 DOI: 10.3390/cells8090981] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Revised: 08/20/2019] [Accepted: 08/23/2019] [Indexed: 02/06/2023] Open
Abstract
The subunits KCNQ1 and KCNE1 generate the slowly activating, delayed rectifier potassium current, IKs, that responds to sympathetic stimulation and is critical for human cardiac repolarization. The A-kinase anchoring protein Yotiao facilitates macromolecular complex formation between IKs and protein kinase A (PKA) to regulate phosphorylation of KCNQ1 and IKs currents following beta-adrenergic stimulation. We have previously shown that adenylyl cyclase Type 9 (AC9) is associated with a KCNQ1-Yotiao-PKA complex and facilitates isoproterenol-stimulated phosphorylation of KCNQ1 in an immortalized cell line. However, requirement for AC9 in sympathetic control of IKs in the heart was unknown. Using a transgenic mouse strain expressing the KCNQ1-KCNE1 subunits of IKs, we show that AC9 is the only adenylyl cyclase (AC) isoform associated with the KCNQ1-KCNE1-Yotiao complex in the heart. Deletion of AC9 resulted in the loss of isoproterenol-stimulated KCNQ1 phosphorylation in vivo, even though AC9 represents less than 3% of total cardiac AC activity. Importantly, a significant reduction of isoproterenol-stimulated IKs currents was also observed in adult cardiomyocytes from IKs-expressing AC9KO mice. AC9 and Yotiao co-localize with N-cadherin, a marker of intercalated disks and cell–cell junctions, in neonatal and adult cardiomyocytes, respectively. In conclusion, AC9 is necessary for sympathetic regulation of PKA phosphorylation of KCNQ1 in vivo and for functional regulation of IKs in adult cardiomyocytes.
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Affiliation(s)
- Yong Li
- Department of Integrative Biology and Pharmacology, McGovern Medical School, University of Texas Health Science Center, Houston, TX 77030, USA
| | - Thomas Hof
- Department of Pharmacology, Department of Medicine, College of Physicians and Surgeons of Columbia University, New York, NY 10032, USA
| | - Tanya A Baldwin
- Department of Integrative Biology and Pharmacology, McGovern Medical School, University of Texas Health Science Center, Houston, TX 77030, USA
| | - Lei Chen
- Department of Pharmacology, Department of Medicine, College of Physicians and Surgeons of Columbia University, New York, NY 10032, USA
| | - Robert S Kass
- Department of Pharmacology, Department of Medicine, College of Physicians and Surgeons of Columbia University, New York, NY 10032, USA
| | - Carmen W Dessauer
- Department of Integrative Biology and Pharmacology, McGovern Medical School, University of Texas Health Science Center, Houston, TX 77030, USA.
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26
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Ekins S, Gerlach J, Zorn KM, Antonio BM, Lin Z, Gerlach A. Repurposing Approved Drugs as Inhibitors of K v7.1 and Na v1.8 to Treat Pitt Hopkins Syndrome. Pharm Res 2019; 36:137. [PMID: 31332533 DOI: 10.1007/s11095-019-2671-y] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Accepted: 07/10/2019] [Indexed: 12/18/2022]
Abstract
PURPOSE Pitt Hopkins Syndrome (PTHS) is a rare genetic disorder caused by mutations of a specific gene, transcription factor 4 (TCF4), located on chromosome 18. PTHS results in individuals that have moderate to severe intellectual disability, with most exhibiting psychomotor delay. PTHS also exhibits features of autistic spectrum disorders, which are characterized by the impaired ability to communicate and socialize. PTHS is comorbid with a higher prevalence of epileptic seizures which can be present from birth or which commonly develop in childhood. Attenuated or absent TCF4 expression results in increased translation of peripheral ion channels Kv7.1 and Nav1.8 which triggers an increase in after-hyperpolarization and altered firing properties. METHODS We now describe a high throughput screen (HTS) of 1280 approved drugs and machine learning models developed from this data. The ion channels were expressed in either CHO (KV7.1) or HEK293 (Nav1.8) cells and the HTS used either 86Rb+ efflux (KV7.1) or a FLIPR assay (Nav1.8). RESULTS The HTS delivered 55 inhibitors of Kv7.1 (4.2% hit rate) and 93 inhibitors of Nav1.8 (7.2% hit rate) at a screening concentration of 10 μM. These datasets also enabled us to generate and validate Bayesian machine learning models for these ion channels. We also describe a structure activity relationship for several dihydropyridine compounds as inhibitors of Nav1.8. CONCLUSIONS This work could lead to the potential repurposing of nicardipine or other dihydropyridine calcium channel antagonists as potential treatments for PTHS acting via Nav1.8, as there are currently no approved treatments for this rare disorder.
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Affiliation(s)
- Sean Ekins
- Collaborations Pharmaceuticals, Inc., 840 Main Campus Drive, Lab 3510, Raleigh, North Carolina, 27606, USA.
| | - Jacob Gerlach
- Collaborations Pharmaceuticals, Inc., 840 Main Campus Drive, Lab 3510, Raleigh, North Carolina, 27606, USA
| | - Kimberley M Zorn
- Collaborations Pharmaceuticals, Inc., 840 Main Campus Drive, Lab 3510, Raleigh, North Carolina, 27606, USA
| | - Brett M Antonio
- Icagen, Inc., 4222 Emperor Blvd, Durham, North Carolina, 27703, USA
| | - Zhixin Lin
- Icagen, Inc., 4222 Emperor Blvd, Durham, North Carolina, 27703, USA
| | - Aaron Gerlach
- Icagen, Inc., 4222 Emperor Blvd, Durham, North Carolina, 27703, USA
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27
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Ray S, Salzer I, Kronschläger MT, Boehm S. The paracetamol metabolite N-acetylp-benzoquinone imine reduces excitability in first- and second-order neurons of the pain pathway through actions on KV7 channels. Pain 2019; 160:954-964. [PMID: 30601242 PMCID: PMC6430418 DOI: 10.1097/j.pain.0000000000001474] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Revised: 12/17/2018] [Accepted: 12/17/2018] [Indexed: 12/14/2022]
Abstract
Paracetamol (acetaminophen, APAP) is one of the most frequently used analgesic agents worldwide. It is generally preferred over nonsteroidal anti-inflammatory drugs because it does not cause typical adverse effects resulting from the inhibition of cyclooxygenases, such as gastric ulcers. Nevertheless, inhibitory impact on these enzymes is claimed to contribute to paracetamols mechanisms of action which, therefore, remained controversial. Recently, the APAP metabolites N-arachidonoylaminophenol (AM404) and N-acetyl-p-benzoquinone imine (NAPQI) have been detected in the central nervous system after systemic APAP administration and were reported to mediate paracetamol effects. In contrast to nonsteroidal anti-inflammatory drugs that rather support seizure activity, paracetamol provides anticonvulsant actions, and this dampening of neuronal activity may also form the basis for analgesic effects. Here, we reveal that the APAP metabolite NAPQI, but neither the parent compound nor the metabolite AM404, reduces membrane excitability in rat dorsal root ganglion (DRG) and spinal dorsal horn (SDH) neurons. The observed reduction of spike frequencies is accompanied by hyperpolarization in both sets of neurons. In parallel, NAPQI, but neither APAP nor AM404, increases currents through KV7 channels in DRG and SDH neurons, and the impact on neuronal excitability is absent if KV7 channels are blocked. Furthermore, NAPQI can revert the inhibitory action of the inflammatory mediator bradykinin on KV7 channels but does not affect synaptic transmission between DRG and SDH neurons. These results show that the paracetamol metabolite NAPQI dampens excitability of first- and second-order neurons of the pain pathway through an action on KV7 channels.
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Affiliation(s)
- Sutirtha Ray
- Division of Neurophysiology and Neuropharmacology, Center for Physiology and Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Isabella Salzer
- Division of Neurophysiology and Neuropharmacology, Center for Physiology and Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Mira T. Kronschläger
- Department of Neurophysiology, Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Stefan Boehm
- Division of Neurophysiology and Neuropharmacology, Center for Physiology and Pharmacology, Medical University of Vienna, Vienna, Austria
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28
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De Silva AM, Manville RW, Abbott GW. Deconstruction of an African folk medicine uncovers a novel molecular strategy for therapeutic potassium channel activation. Sci Adv 2018; 4:eaav0824. [PMID: 30443601 PMCID: PMC6235520 DOI: 10.1126/sciadv.aav0824] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2018] [Accepted: 10/18/2018] [Indexed: 05/02/2023]
Abstract
A third of the global population relies heavily upon traditional or folk medicines, such as the African shrub Mallotus oppositifolius. Here, we used pharmacological screening and electrophysiological analysis in combination with in silico docking and site-directed mutagenesis to elucidate the effects of M. oppositifolius constituents on KCNQ1, a ubiquitous and influential cardiac and epithelial voltage-gated potassium (Kv) channel. Two components of the M. oppositifolius leaf extract, mallotoxin (MTX) and 3-ethyl-2-hydroxy-2-cyclopenten-1-one (CPT1), augmented KCNQ1 current by negative shifting its voltage dependence of activation. MTX was also highly effective at augmenting currents generated by KCNQ1 in complexes with native partners KCNE1 or SMIT1; conversely, MTX inhibited KCNQ1-KCNE3 channels. MTX and CPT1 activated KCNQ1 by hydrogen bonding to the foot of the voltage sensor, a previously unidentified drug site which we also find to be essential for MTX activation of the related KCNQ2/3 channel. The findings elucidate the molecular mechanistic basis for modulation by a widely used folk medicine of an important human Kv channel and uncover novel molecular approaches for therapeutic modulation of potassium channel activity.
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29
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Masuda K, Takanari H, Morishima M, Ma F, Wang Y, Takahashi N, Ono K. Testosterone-mediated upregulation of delayed rectifier potassium channel in cardiomyocytes causes abbreviation of QT intervals in rats. J Physiol Sci 2018; 68:759-767. [PMID: 29332211 PMCID: PMC10717990 DOI: 10.1007/s12576-017-0590-4] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Accepted: 12/26/2017] [Indexed: 12/01/2022]
Abstract
Men have shorter rate-corrected QT intervals (QTc) than women, especially at the period of adolescence or later. The aim of this study was to elucidate the long-term effects of testosterone on cardiac excitability parameters including electrocardiogram (ECG) and potassium channel current. Testosterone shortened QT intervals in ECG in castrated male rats, not immediately after, but on day 2 or later. Expression of Kv7.1 (KCNQ1) mRNA was significantly upregulated by testosterone in cardiomyocytes of male and female rats. Short-term application of testosterone was without effect on delayed rectifier potassium channel current (IKs), whereas IKs was significantly increased in cardiomyocytes treated with dihydrotestosterone for 24 h, which was mimicked by isoproterenol (24 h). Gene-selective inhibitors of a transcription factor SP1, mithramycin, abolished the effects of testosterone on Kv7.1. Testosterone increases Kv7.1-IKs possibly through a pathway related to a transcription factor SP1, suggesting a genomic effect of testosterone as an active factor for cardiac excitability.
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Affiliation(s)
- Kimiko Masuda
- Department of Cardiology and Clinical Examination, Oita University School of Medicine, Yufu, Oita, 879-5593, Japan
- Department of Pathophysiology, Oita University School of Medicine, 1-1 Idaigaoka, Hasama, Yufu, Oita, 879-5593, Japan
| | - Hiroki Takanari
- Department of Pathophysiology, Oita University School of Medicine, 1-1 Idaigaoka, Hasama, Yufu, Oita, 879-5593, Japan
| | - Masaki Morishima
- Department of Pathophysiology, Oita University School of Medicine, 1-1 Idaigaoka, Hasama, Yufu, Oita, 879-5593, Japan
| | - FangFang Ma
- Department of Pathophysiology, Oita University School of Medicine, 1-1 Idaigaoka, Hasama, Yufu, Oita, 879-5593, Japan
| | - Yan Wang
- Department of Cardiology and Clinical Examination, Oita University School of Medicine, Yufu, Oita, 879-5593, Japan
- Department of Pathophysiology, Oita University School of Medicine, 1-1 Idaigaoka, Hasama, Yufu, Oita, 879-5593, Japan
| | - Naohiko Takahashi
- Department of Cardiology and Clinical Examination, Oita University School of Medicine, Yufu, Oita, 879-5593, Japan
| | - Katsushige Ono
- Department of Pathophysiology, Oita University School of Medicine, 1-1 Idaigaoka, Hasama, Yufu, Oita, 879-5593, Japan.
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30
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Abramochkin DV, Hassinen M, Vornanen M. Transcripts of Kv7.1 and MinK channels and slow delayed rectifier K + current (I Ks) are expressed in zebrafish (Danio rerio) heart. Pflugers Arch 2018; 470:1753-1764. [PMID: 30116893 DOI: 10.1007/s00424-018-2193-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Revised: 07/24/2018] [Accepted: 08/06/2018] [Indexed: 12/18/2022]
Abstract
Zebrafish are increasingly used as a model for human cardiac electrophysiology, arrhythmias, and drug screening. However, K+ ion channels of the zebrafish heart, which determine the rate of repolarization and duration of cardiac action potential (AP) are still incompletely known and characterized. Here, we provide the first evidence for the presence of the slow component of the delayed rectifier K+channels in the zebrafish heart and characterize electrophysiological properties of the slow component of the delayed rectifier K+current, IKs. Zebrafish atrium and ventricle showed strong transcript expression of the kcnq1 gene, which encodes the Kv7.1 α-subunit of the slow delayed rectifier K+ channel. In contrast, the kcne1 gene, encoding the MinK β-subunit of the delayed rectifier, was expressed at 21 and 17 times lower level in ventricle and atrium, respectively, in comparison to the kcnq1. IKs was observed in 62% of ventricular myocytes with mean (± SEM) density of 1.23 ± 0.37 pA/pF at + 30 mV. Activation rate of IKs was 38% faster (τ50 = 1248 ± 215 ms) than kcnq1:kcne1 channels (1725 ± 792 ms) expressed in 3:1 ratio in Chinese hamster ovary cells. Microelectrode experiments demonstrated the functional relevance of IKs in the zebrafish heart, since 100 μM chromanol 293B produced a significant prolongation of AP in zebrafish ventricle. We conclude that AP repolarization in zebrafish ventricle is contributed by IKs, which is mainly generated by homotetrameric Kv7.1 channels not coupled to MinK ancillary β-subunits. This is a clear difference to the human heart, where MinK is an essential component of the slow delayed rectifier K+channel.
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Affiliation(s)
- Denis V Abramochkin
- Department of Human and Animal Physiology, Biological faculty, Lomonosov Moscow State University, Leninskiye Gory, 1, 12, Moscow, Russia.
- Department of Physiology, Pirogov Russian National Research Medical University, Moscow, Russia.
- Laboratory of Cardiac Physiology, Institute of Physiology, Komi Science Center, Ural Branch, Russian Academy of Sciences, Syktyvkar, Russia.
| | - Minna Hassinen
- Department of Environmental and Biological Sciences, University of Eastern Finland, Joensuu, Finland
| | - Matti Vornanen
- Department of Environmental and Biological Sciences, University of Eastern Finland, Joensuu, Finland
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31
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Kumar S, Aswal VK, Agrawal RP, Quoseena M, Jillellamudi C, Kapur S, Toshan NC. SNP in KCNQ1 Gene is Associated with Susceptibility to Diabetic Nephropathy in Subjects with Type 2 Diabetes in India. J Assoc Physicians India 2018; 66:58-61. [PMID: 31324086] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
OBJECTIVE Diabetic nephropathy (DN) remains the most common cause of end stage renal disease (ESRD) as the burden of diabetes increases worldwide. Only 25 to 40% of patients with type 2 diabetes mellitus (T2DM) develop diabetic nephropathy irrespective of glycemic control so there should be a specific genetic basis for the development of diabetic nephropathy. METHODS We have collected venous blood samples from 50 cases (Diabetic nephropathy) and 20 controls (T2DM without nephropathy) diagnosed by spot urine albumin creatinine ratio (ACR). DNA was isolated from processed samples. PCR study and sequencing was done to detect polymorphism of rs2237897 in KCNQ1 gene. RESULTS Statistically significant difference was found when the allelic frequencies between the two groups were compared (p=0.03), with the C allele having a 2.4 fold higher risk of having diabetic nephropathy (risk ratio, RR )= 1.16, 95%CI of RR = 1.01 to 1.3, Odds Ratio (OR) =2.4; 95% CI of OR =1.06 to 4.6). Chi-square analysis showed a significant difference in genotype frequency of rs2237897 (χ2 = 4.63, p=0.03) in Diabetic nephropathy subjects, compared with that of controls. CONCLUSIONS This study suggested that, KCNQ1 being an established type 2 diabetes gene, genetic variation in this gene may contribute to susceptibility to diabetic nephropathy and the C allele is the risk allele for diabetic nephropathy, which is different from Japanese population where the T allele was the risk allele.
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Affiliation(s)
- Surendra Kumar
- Professor, Principal and Controller, S.P. Medical College, Bikaner, Rajasthan, Corresponding Author
| | - Vinod Kumar Aswal
- Assistant Professor, Principal and Controller, S.P. Medical College, Bikaner, Rajasthan
| | - R P Agrawal
- Senior Professor, Principal and Controller, S.P. Medical College, Bikaner, Rajasthan
| | - Mir Quoseena
- JRF, Head of the Department of Biological Sciences, BITS- Pilani, Hyderabad Campus, Hyderabad, Telangana
| | - Chinmayi Jillellamudi
- Phd Scholar, Head of the Department of Biological Sciences, BITS- Pilani, Hyderabad Campus, Hyderabad, Telangana
| | - Suman Kapur
- Senior Professor, Head of the Department of Biological Sciences, BITS- Pilani, Hyderabad Campus, Hyderabad, Telangana
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Yuniarti AR, Setianto F, Marcellinus A, Hwang HJ, Choi SW, Trayanova N, Lim KM. Effect of KCNQ1 G229D mutation on cardiac pumping efficacy and reentrant dynamics in ventricles: Computational study. Int J Numer Method Biomed Eng 2018; 34:e2970. [PMID: 29488358 PMCID: PMC6556218 DOI: 10.1002/cnm.2970] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Revised: 02/09/2018] [Accepted: 02/12/2018] [Indexed: 05/12/2023]
Abstract
There is growing interest in genetic arrhythmia since mutations in gene which encodes the ion channel underlie numerous arrhythmias. Hasegawa et al reported that G229D mutation in KCNQ1 underlies atrial fibrillation due to significant shortening of action potential duration (APD) in atrial cells. Here, we predicted whether KCNQ1 G229D mutation affects ventricular fibrillation generation, although it shortens APD slightly compared with the atrial cell. We analyzed the effects of G229D mutation on electrical and mechanical ventricle behaviors (not considered in previous studies). We compared action potential shapes under wild-type and mutant conditions. Electrical wave propagations through ventricles were analyzed during sinus rhythm and reentrant conditions. IKs enhancement due to G229D mutation shortened the APD in the ventricular cells (6%, 0.3%, and 8% for endo, M, and epi-cells, respectively). The shortened APD contributed to 7% shortening of QT intervals, 29% shortening of wavelengths, 20% decrease in intraventricular pressure, and increase in end-systolic volume 17%, end-diastolic volume 7%, and end-diastolic pressure 11%, which further resulted in reduction in stroke volume as well as cardiac output (28%), ejection fraction 33% stroke work 44%, and ATP consumption 28%. In short, using computational model of the ventricle, we predicted that G229D mutation decreased cardiac pumping efficacy and increased the vulnerability of ventricular fibrillation.
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Affiliation(s)
- Ana Rahma Yuniarti
- Department of IT Convergence Engineering, Kumoh National Institute of Technology, Gumi, South Korea
| | - Febrian Setianto
- Department of IT Convergence Engineering, Kumoh National Institute of Technology, Gumi, South Korea
| | - Aroli Marcellinus
- Department of IT Convergence Engineering, Kumoh National Institute of Technology, Gumi, South Korea
| | - Han Jeong Hwang
- Department of IT Convergence Engineering, Kumoh National Institute of Technology, Gumi, South Korea
| | - Seong Wook Choi
- Department of Mechanical & Biomedical Engineering, Kangwon National University, Chuncheon, South Korea
| | - Natalia Trayanova
- Department of Biomedical Engineering, Institute for Computational Medicine, Johns Hopkins University, Baltimore, MD, USA
| | - Ki Moo Lim
- Department of IT Convergence Engineering, Kumoh National Institute of Technology, Gumi, South Korea
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33
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Li B, Mendenhall JL, Kroncke BM, Taylor KC, Huang H, Smith DK, Vanoye CG, Blume JD, George AL, Sanders CR, Meiler J. Predicting the Functional Impact of KCNQ1 Variants of Unknown Significance. ACTA ACUST UNITED AC 2018; 10:CIRCGENETICS.117.001754. [PMID: 29021305 DOI: 10.1161/circgenetics.117.001754] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2017] [Accepted: 08/24/2017] [Indexed: 12/22/2022]
Abstract
BACKGROUND An emerging standard-of-care for long-QT syndrome uses clinical genetic testing to identify genetic variants of the KCNQ1 potassium channel. However, interpreting results from genetic testing is confounded by the presence of variants of unknown significance for which there is inadequate evidence of pathogenicity. METHODS AND RESULTS In this study, we curated from the literature a high-quality set of 107 functionally characterized KCNQ1 variants. Based on this data set, we completed a detailed quantitative analysis on the sequence conservation patterns of subdomains of KCNQ1 and the distribution of pathogenic variants therein. We found that conserved subdomains generally are critical for channel function and are enriched with dysfunctional variants. Using this experimentally validated data set, we trained a neural network, designated Q1VarPred, specifically for predicting the functional impact of KCNQ1 variants of unknown significance. The estimated predictive performance of Q1VarPred in terms of Matthew's correlation coefficient and area under the receiver operating characteristic curve were 0.581 and 0.884, respectively, superior to the performance of 8 previous methods tested in parallel. Q1VarPred is publicly available as a web server at http://meilerlab.org/q1varpred. CONCLUSIONS Although a plethora of tools are available for making pathogenicity predictions over a genome-wide scale, previous tools fail to perform in a robust manner when applied to KCNQ1. The contrasting and favorable results for Q1VarPred suggest a promising approach, where a machine-learning algorithm is tailored to a specific protein target and trained with a functionally validated data set to calibrate informatics tools.
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Affiliation(s)
- Bian Li
- From the Department of Chemistry (B.L., J.L.M., J.M.), Center for Structural Biology (B.L., J.L.M., B.M.K., K.C.T., H.H., C.R.S., J.M.), Department of Biochemistry (B.M.K., H.H., C.R.S.), and Department of Biostatistics (D.K.S., J.D.B.), Vanderbilt University, Nashville, TN; Department of Medicine, Vanderbilt University Medical Center, Nashville, TN (B.M.K., C.R.S.); and Department of Pharmacology, Northwestern University Feinberg School of Medicine, Chicago, IL (C.G.V., A.L.G.)
| | - Jeffrey L Mendenhall
- From the Department of Chemistry (B.L., J.L.M., J.M.), Center for Structural Biology (B.L., J.L.M., B.M.K., K.C.T., H.H., C.R.S., J.M.), Department of Biochemistry (B.M.K., H.H., C.R.S.), and Department of Biostatistics (D.K.S., J.D.B.), Vanderbilt University, Nashville, TN; Department of Medicine, Vanderbilt University Medical Center, Nashville, TN (B.M.K., C.R.S.); and Department of Pharmacology, Northwestern University Feinberg School of Medicine, Chicago, IL (C.G.V., A.L.G.)
| | - Brett M Kroncke
- From the Department of Chemistry (B.L., J.L.M., J.M.), Center for Structural Biology (B.L., J.L.M., B.M.K., K.C.T., H.H., C.R.S., J.M.), Department of Biochemistry (B.M.K., H.H., C.R.S.), and Department of Biostatistics (D.K.S., J.D.B.), Vanderbilt University, Nashville, TN; Department of Medicine, Vanderbilt University Medical Center, Nashville, TN (B.M.K., C.R.S.); and Department of Pharmacology, Northwestern University Feinberg School of Medicine, Chicago, IL (C.G.V., A.L.G.)
| | - Keenan C Taylor
- From the Department of Chemistry (B.L., J.L.M., J.M.), Center for Structural Biology (B.L., J.L.M., B.M.K., K.C.T., H.H., C.R.S., J.M.), Department of Biochemistry (B.M.K., H.H., C.R.S.), and Department of Biostatistics (D.K.S., J.D.B.), Vanderbilt University, Nashville, TN; Department of Medicine, Vanderbilt University Medical Center, Nashville, TN (B.M.K., C.R.S.); and Department of Pharmacology, Northwestern University Feinberg School of Medicine, Chicago, IL (C.G.V., A.L.G.)
| | - Hui Huang
- From the Department of Chemistry (B.L., J.L.M., J.M.), Center for Structural Biology (B.L., J.L.M., B.M.K., K.C.T., H.H., C.R.S., J.M.), Department of Biochemistry (B.M.K., H.H., C.R.S.), and Department of Biostatistics (D.K.S., J.D.B.), Vanderbilt University, Nashville, TN; Department of Medicine, Vanderbilt University Medical Center, Nashville, TN (B.M.K., C.R.S.); and Department of Pharmacology, Northwestern University Feinberg School of Medicine, Chicago, IL (C.G.V., A.L.G.)
| | - Derek K Smith
- From the Department of Chemistry (B.L., J.L.M., J.M.), Center for Structural Biology (B.L., J.L.M., B.M.K., K.C.T., H.H., C.R.S., J.M.), Department of Biochemistry (B.M.K., H.H., C.R.S.), and Department of Biostatistics (D.K.S., J.D.B.), Vanderbilt University, Nashville, TN; Department of Medicine, Vanderbilt University Medical Center, Nashville, TN (B.M.K., C.R.S.); and Department of Pharmacology, Northwestern University Feinberg School of Medicine, Chicago, IL (C.G.V., A.L.G.)
| | - Carlos G Vanoye
- From the Department of Chemistry (B.L., J.L.M., J.M.), Center for Structural Biology (B.L., J.L.M., B.M.K., K.C.T., H.H., C.R.S., J.M.), Department of Biochemistry (B.M.K., H.H., C.R.S.), and Department of Biostatistics (D.K.S., J.D.B.), Vanderbilt University, Nashville, TN; Department of Medicine, Vanderbilt University Medical Center, Nashville, TN (B.M.K., C.R.S.); and Department of Pharmacology, Northwestern University Feinberg School of Medicine, Chicago, IL (C.G.V., A.L.G.)
| | - Jeffrey D Blume
- From the Department of Chemistry (B.L., J.L.M., J.M.), Center for Structural Biology (B.L., J.L.M., B.M.K., K.C.T., H.H., C.R.S., J.M.), Department of Biochemistry (B.M.K., H.H., C.R.S.), and Department of Biostatistics (D.K.S., J.D.B.), Vanderbilt University, Nashville, TN; Department of Medicine, Vanderbilt University Medical Center, Nashville, TN (B.M.K., C.R.S.); and Department of Pharmacology, Northwestern University Feinberg School of Medicine, Chicago, IL (C.G.V., A.L.G.)
| | - Alfred L George
- From the Department of Chemistry (B.L., J.L.M., J.M.), Center for Structural Biology (B.L., J.L.M., B.M.K., K.C.T., H.H., C.R.S., J.M.), Department of Biochemistry (B.M.K., H.H., C.R.S.), and Department of Biostatistics (D.K.S., J.D.B.), Vanderbilt University, Nashville, TN; Department of Medicine, Vanderbilt University Medical Center, Nashville, TN (B.M.K., C.R.S.); and Department of Pharmacology, Northwestern University Feinberg School of Medicine, Chicago, IL (C.G.V., A.L.G.)
| | - Charles R Sanders
- From the Department of Chemistry (B.L., J.L.M., J.M.), Center for Structural Biology (B.L., J.L.M., B.M.K., K.C.T., H.H., C.R.S., J.M.), Department of Biochemistry (B.M.K., H.H., C.R.S.), and Department of Biostatistics (D.K.S., J.D.B.), Vanderbilt University, Nashville, TN; Department of Medicine, Vanderbilt University Medical Center, Nashville, TN (B.M.K., C.R.S.); and Department of Pharmacology, Northwestern University Feinberg School of Medicine, Chicago, IL (C.G.V., A.L.G.)
| | - Jens Meiler
- From the Department of Chemistry (B.L., J.L.M., J.M.), Center for Structural Biology (B.L., J.L.M., B.M.K., K.C.T., H.H., C.R.S., J.M.), Department of Biochemistry (B.M.K., H.H., C.R.S.), and Department of Biostatistics (D.K.S., J.D.B.), Vanderbilt University, Nashville, TN; Department of Medicine, Vanderbilt University Medical Center, Nashville, TN (B.M.K., C.R.S.); and Department of Pharmacology, Northwestern University Feinberg School of Medicine, Chicago, IL (C.G.V., A.L.G.).
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Lee HA, Hyun SA, Byun B, Chae JH, Kim KS. Electrophysiological mechanisms of vandetanib-induced cardiotoxicity: Comparison of action potentials in rabbit Purkinje fibers and pluripotent stem cell-derived cardiomyocytes. PLoS One 2018; 13:e0195577. [PMID: 29630634 PMCID: PMC5891061 DOI: 10.1371/journal.pone.0195577] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2017] [Accepted: 03/26/2018] [Indexed: 01/08/2023] Open
Abstract
Vandetanib, a multi-kinase inhibitor used for the treatment of various cancers, has been reported to induce several adverse cardiac effects. However, the underlying mechanisms of vandetanib-induced cardiotoxicity are unclear. This study aimed to investigate the mechanism of vandetanib-induced cardiotoxicity using intracellular electrophysiological recordings on human-induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs), rabbit Purkinje fibers, and HEK293 cells transiently expressing human ether-a-go-go-related gene (hERG; the rapidly activating delayed rectifier K+ channel, IKr), KCNQ1/KCNE1 (the slowly activating delayed rectifier K+ current, IKs), KCNJ2 (the inwardly rectifying K+ current, IK1) or SCN5A (the inward Na+ current, INa). Purkinje fiber assays and ion channel studies showed that vandetanib at concentrations of 1 and 3 μM inhibited the hERG currents and prolonged the action potential duration. Alanine scanning and in silico hERG docking studies demonstrated that Y652 and F656 in the hERG S6 domain play critical roles in vandetanib binding. In hiPSC-CMs, vandetanib markedly reduced the maximum rate of depolarization during the AP upstroke. Ion channel studies revealed that hiPSC-CMs were more sensitive to inhibition of the INa by vandetanib than in a heterogeneously expressed HEK293 cell model, consistent with the changes in the AP parameters of hiPSC-CMs. The subclasses of Class I antiarrhythmic drugs inhibited INa currents in a dose-dependent manner in hiPSC-CMs and SCN5A-encoded HEK293 cells. The inhibitory potency of vandetanib for INa was much higher in hiPSC-CMs (IC50: 2.72 μM) than in HEK293 cells (IC50: 36.63 μM). These data suggest that AP and INa assays using hiPSC-CMs are useful electrophysiological models for prediction of drug-induced cardiotoxicity.
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Affiliation(s)
- Hyang-Ae Lee
- Predictive model Research Center, Korea Institute of Toxicology, Korea Research Institute of Chemical Technology, Daejeon, South Korea
| | - Sung-Ae Hyun
- Research Center for Safety Pharmacology, Korea Institute of Toxicology, Research Institute of Chemical Technology, Daejeon, South Korea
| | - Byungjin Byun
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana, United States of America
| | - Jong-Hak Chae
- Korea Research Institute of Chemical Technology, Daejeon, South Korea
| | - Ki-Suk Kim
- Predictive model Research Center, Korea Institute of Toxicology, Korea Research Institute of Chemical Technology, Daejeon, South Korea
- Department of Human and Environmental Toxicology, University of Science and Technology, Daejeon, South Korea
- * E-mail: ,
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Huang H, Kuenze G, Smith JA, Taylor KC, Duran AM, Hadziselimovic A, Meiler J, Vanoye CG, George AL, Sanders CR. Mechanisms of KCNQ1 channel dysfunction in long QT syndrome involving voltage sensor domain mutations. Sci Adv 2018; 4:eaar2631. [PMID: 29532034 PMCID: PMC5842040 DOI: 10.1126/sciadv.aar2631] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2017] [Accepted: 02/02/2018] [Indexed: 05/21/2023]
Abstract
Mutations that induce loss of function (LOF) or dysfunction of the human KCNQ1 channel are responsible for susceptibility to a life-threatening heart rhythm disorder, the congenital long QT syndrome (LQTS). Hundreds of KCNQ1 mutations have been identified, but the molecular mechanisms responsible for impaired function are poorly understood. We investigated the impact of 51 KCNQ1 variants with mutations located within the voltage sensor domain (VSD), with an emphasis on elucidating effects on cell surface expression, protein folding, and structure. For each variant, the efficiency of trafficking to the plasma membrane, the impact of proteasome inhibition, and protein stability were assayed. The results of these experiments combined with channel functional data provided the basis for classifying each mutation into one of six mechanistic categories, highlighting heterogeneity in the mechanisms resulting in channel dysfunction or LOF. More than half of the KCNQ1 LOF mutations examined were seen to destabilize the structure of the VSD, generally accompanied by mistrafficking and degradation by the proteasome, an observation that underscores the growing appreciation that mutation-induced destabilization of membrane proteins may be a common human disease mechanism. Finally, we observed that five of the folding-defective LQTS mutant sites are located in the VSD S0 helix, where they interact with a number of other LOF mutation sites in other segments of the VSD. These observations reveal a critical role for the S0 helix as a central scaffold to help organize and stabilize the KCNQ1 VSD and, most likely, the corresponding domain of many other ion channels.
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Affiliation(s)
- Hui Huang
- Department of Biochemistry, Vanderbilt University, Nashville, TN 37240, USA
- Center for Structural Biology, Vanderbilt University, Nashville, TN 37240, USA
| | - Georg Kuenze
- Center for Structural Biology, Vanderbilt University, Nashville, TN 37240, USA
- Department of Chemistry, Vanderbilt University, Nashville, TN 37235, USA
- Department of Pharmacology, Vanderbilt University, Nashville, TN 37240, USA
| | - Jarrod A. Smith
- Department of Biochemistry, Vanderbilt University, Nashville, TN 37240, USA
- Center for Structural Biology, Vanderbilt University, Nashville, TN 37240, USA
| | - Keenan C. Taylor
- Department of Biochemistry, Vanderbilt University, Nashville, TN 37240, USA
- Center for Structural Biology, Vanderbilt University, Nashville, TN 37240, USA
| | - Amanda M. Duran
- Center for Structural Biology, Vanderbilt University, Nashville, TN 37240, USA
- Department of Chemistry, Vanderbilt University, Nashville, TN 37235, USA
- Department of Pharmacology, Vanderbilt University, Nashville, TN 37240, USA
| | - Arina Hadziselimovic
- Department of Biochemistry, Vanderbilt University, Nashville, TN 37240, USA
- Center for Structural Biology, Vanderbilt University, Nashville, TN 37240, USA
| | - Jens Meiler
- Center for Structural Biology, Vanderbilt University, Nashville, TN 37240, USA
- Department of Chemistry, Vanderbilt University, Nashville, TN 37235, USA
- Department of Pharmacology, Vanderbilt University, Nashville, TN 37240, USA
- Department of Bioinformatics, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Carlos G. Vanoye
- Department of Pharmacology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Alfred L. George
- Department of Pharmacology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Charles R. Sanders
- Department of Biochemistry, Vanderbilt University, Nashville, TN 37240, USA
- Center for Structural Biology, Vanderbilt University, Nashville, TN 37240, USA
- Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232, USA
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Jalily Hasani H, Ganesan A, Ahmed M, Barakat KH. Effects of protein-protein interactions and ligand binding on the ion permeation in KCNQ1 potassium channel. PLoS One 2018; 13:e0191905. [PMID: 29444113 PMCID: PMC5812580 DOI: 10.1371/journal.pone.0191905] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Accepted: 01/12/2018] [Indexed: 12/23/2022] Open
Abstract
The voltage-gated KCNQ1 potassium ion channel interacts with the type I transmembrane protein minK (KCNE1) to generate the slow delayed rectifier (IKs) current in the heart. Mutations in these transmembrane proteins have been linked with several heart-related issues, including long QT syndromes (LQTS), congenital atrial fibrillation, and short QT syndrome. Off-target interactions of several drugs with that of KCNQ1/KCNE1 ion channel complex have been known to cause fatal cardiac irregularities. Thus, KCNQ1/KCNE1 remains an important avenue for drug-design and discovery research. In this work, we present the structural and mechanistic details of potassium ion permeation through an open KCNQ1 structural model using the combined molecular dynamics and steered molecular dynamics simulations. We discuss the processes and key residues involved in the permeation of a potassium ion through the KCNQ1 ion channel, and how the ion permeation is affected by (i) the KCNQ1-KCNE1 interactions and (ii) the binding of chromanol 293B ligand and its derivatives into the complex. The results reveal that interactions between KCNQ1 with KCNE1 causes a pore constriction in the former, which in-turn forms small energetic barriers in the ion-permeation pathway. These findings correlate with the previous experimental reports that interactions of KCNE1 dramatically slows the activation of KCNQ1. Upon ligand-binding onto the complex, the energy-barriers along ion permeation path are more pronounced, as expected, therefore, requiring higher force in our steered-MD simulations. Nevertheless, pulling the ion when a weak blocker is bound to the channel does not necessitate high force in SMD. This indicates that our SMD simulations have been able to discern between strong and week blockers and reveal their influence on potassium ion permeation. The findings presented here will have some implications in understanding the potential off-target interactions of the drugs with the KCNQ1/KCNE1 channel that lead to cardiotoxic effects.
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Affiliation(s)
- Horia Jalily Hasani
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Aravindhan Ganesan
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Marawan Ahmed
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Khaled H. Barakat
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Alberta, Canada
- Li Ka Shing Institute of Virology, University of Alberta, Edmonton, Alberta, Canada
- Li Ka Shing Applied Virology Institute, University of Alberta, Edmonton, Alberta, Canada
- * E-mail:
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Jiang Y, Du W, Chu Q, Qin Y, Tuguzbaeva G, Wang H, Li A, Li G, Li Y, Chai L, Yue E, Sun X, Wang Z, Pavlov V, Yang B, Bai Y. Downregulation of Long Non-Coding RNA Kcnq1ot1: An Important Mechanism of Arsenic Trioxide-Induced Long QT Syndrome. Cell Physiol Biochem 2018; 45:192-202. [PMID: 29339628 DOI: 10.1159/000486357] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2016] [Accepted: 11/01/2017] [Indexed: 11/19/2022] Open
Abstract
Background/Aims: Arsenic trioxide (ATO) is a known anti-acute promyelocytic leukemia (APL) reagent, whose clinical applications are limited by its serious cardiac toxicity and fatal adverse effects, such as sudden cardiac death resulting from long QT syndrome (LQTS). The mechanisms of cardiac arrhythmia due to ATO exposure still need to be elucidated. Long non-coding RNAs (lncRNAs) are emerging as major regulators of various pathophysiological processes. This study aimed to explore the involvement of lncRNAs in ATO-induced LQTS in vivo and in vitro. Methods: For in vivo experiments, mice were administered ATO through the tail vein. For in vitro experiments, ATO was added to the culture medium of primary cultured neonatal mouse cardiomyocytes. To evaluate the effect of lncRNA Kcnq1ot1, siRNA and lentivirus-shRNA were synthesized to knockdown lncRNA Kcnq1ot1. Results: After ATO treatment, the Kcnq1ot1 and Kcnq1 expression levels were down regulated. lncRNA Kcnq1ot1 knockdown prolonged the action potential duration (APD) in vitro and exerted LQTS in vivo. Correspondingly, Kcnq1 expression was decreased after silencing lncRNA Kcnq1ot1. However, the knockdown of Kcnq1 exerted no effect on lncRNA Kcnq1ot1 expression. Conclusions: To our knowledge, this report is the first to demonstrate that lncRNA Kcnq1ot1 downregulation is responsible for QT interval prolongation induced by ATO at least partially by repressing Kcnq1 expression. lncRNA Kcnq1ot1 has important pathophysiological functions in the heart and could become a novel antiarrhythmic target.
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Affiliation(s)
- Yanan Jiang
- Department of Pharmacology (State-Province Key Laboratories of Biomedicine- Pharmaceutics of China, Key Laboratory of Cardiovascular Research, Ministry of Education), College of Pharmacy, Harbin Medical University, Harbin, China
| | - Weijie Du
- Department of Pharmacology (State-Province Key Laboratories of Biomedicine- Pharmaceutics of China, Key Laboratory of Cardiovascular Research, Ministry of Education), College of Pharmacy, Harbin Medical University, Harbin, China
| | - Qun Chu
- Department of Pharmacology (State-Province Key Laboratories of Biomedicine- Pharmaceutics of China, Key Laboratory of Cardiovascular Research, Ministry of Education), College of Pharmacy, Harbin Medical University, Harbin, China
| | - Ying Qin
- Translational Medicine Research and Cooperation Center of Northern China, Heilongjiang Academy of Medical Sciences, Harbin, China
| | - Gulnara Tuguzbaeva
- Translational Medicine Research and Cooperation Center of Northern China, Heilongjiang Academy of Medical Sciences, Harbin, China
- Central laboratory of scientific research, Bashkir State Medical University, Ufa, Russian Federation
| | - Hui Wang
- Department of Pharmacology (State-Province Key Laboratories of Biomedicine- Pharmaceutics of China, Key Laboratory of Cardiovascular Research, Ministry of Education), College of Pharmacy, Harbin Medical University, Harbin, China
| | - Anqi Li
- Department of Pharmacology (State-Province Key Laboratories of Biomedicine- Pharmaceutics of China, Key Laboratory of Cardiovascular Research, Ministry of Education), College of Pharmacy, Harbin Medical University, Harbin, China
| | - Guiyang Li
- Department of Pharmacology (State-Province Key Laboratories of Biomedicine- Pharmaceutics of China, Key Laboratory of Cardiovascular Research, Ministry of Education), College of Pharmacy, Harbin Medical University, Harbin, China
| | - Yanyao Li
- Department of Pharmacology (State-Province Key Laboratories of Biomedicine- Pharmaceutics of China, Key Laboratory of Cardiovascular Research, Ministry of Education), College of Pharmacy, Harbin Medical University, Harbin, China
| | - Lu Chai
- Department of Pharmacology (State-Province Key Laboratories of Biomedicine- Pharmaceutics of China, Key Laboratory of Cardiovascular Research, Ministry of Education), College of Pharmacy, Harbin Medical University, Harbin, China
| | - Er Yue
- Department of Pharmacology (State-Province Key Laboratories of Biomedicine- Pharmaceutics of China, Key Laboratory of Cardiovascular Research, Ministry of Education), College of Pharmacy, Harbin Medical University, Harbin, China
| | - Xi Sun
- Department of Pharmacology (State-Province Key Laboratories of Biomedicine- Pharmaceutics of China, Key Laboratory of Cardiovascular Research, Ministry of Education), College of Pharmacy, Harbin Medical University, Harbin, China
| | - Zhiguo Wang
- Translational Medicine Research and Cooperation Center of Northern China, Heilongjiang Academy of Medical Sciences, Harbin, China
| | - Valentin Pavlov
- Central laboratory of scientific research, Bashkir State Medical University, Ufa, Russian Federation
| | - Baofeng Yang
- Department of Pharmacology (State-Province Key Laboratories of Biomedicine- Pharmaceutics of China, Key Laboratory of Cardiovascular Research, Ministry of Education), College of Pharmacy, Harbin Medical University, Harbin, China
- Translational Medicine Research and Cooperation Center of Northern China, Heilongjiang Academy of Medical Sciences, Harbin, China
- Department of Pharmacology and Therapeutics, Melbourne School of Biomedical Sciences, Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Melbourne, Victoria, Australia
| | - Yunlong Bai
- Department of Pharmacology (State-Province Key Laboratories of Biomedicine- Pharmaceutics of China, Key Laboratory of Cardiovascular Research, Ministry of Education), College of Pharmacy, Harbin Medical University, Harbin, China
- Translational Medicine Research and Cooperation Center of Northern China, Heilongjiang Academy of Medical Sciences, Harbin, China
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Tobelaim WS, Dvir M, Lebel G, Cui M, Buki T, Peretz A, Marom M, Haitin Y, Logothetis DE, Hirsch JA, Attali B. Ca 2+-Calmodulin and PIP2 interactions at the proximal C-terminus of Kv7 channels. Channels (Austin) 2017; 11:686-695. [PMID: 28976808 PMCID: PMC5786183 DOI: 10.1080/19336950.2017.1388478] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Revised: 09/18/2017] [Accepted: 09/29/2017] [Indexed: 10/18/2022] Open
Abstract
In the heart, co-assembly of Kv7.1 with KCNE1 produces the slow IKS potassium current, which repolarizes the cardiac action potential and mutations in human Kv7.1 and KCNE1 genes cause cardiac arrhythmias. The proximal Kv7.1 C-terminus binds calmodulin (CaM) and phosphatidylinositol-4,5-bisphosphate (PIP2) and recently we revealed the competition of PIP2 with the calcified CaM N-lobe to a previously unidentified site in Kv7.1 helix B, also known to harbor a LQT mutation. Data indicated that PIP2 and Ca2+-CaM perform the same function on IKS channel gating to stabilize the channel open state. Here we show that similar features were observed for Kv7.1 currents expressed alone. We also find that conservation of homologous residues in helix B of other Kv7 subtypes confer similar competition of Ca2+-CaM with PIP2 binding to their proximal C-termini and suggest that PIP2-CaM interactions converge to Kv7 helix B to modulates channel activity in a Kv7 subtype-dependent manner.
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Affiliation(s)
- William S. Tobelaim
- Department of Physiology & Pharmacology, Sackler Faculty of Medicine and Sagol School of Neurosciences, Tel Aviv University, Tel Aviv, Israel
| | - Meidan Dvir
- Department of Physiology & Pharmacology, Sackler Faculty of Medicine and Sagol School of Neurosciences, Tel Aviv University, Tel Aviv, Israel
| | - Guy Lebel
- Department of Biochemistry & Molecular Biology, George S. Wise Faculty of Life Sciences, Institute of Structural Biology, Tel Aviv University, Tel Aviv, Israel
| | - Meng Cui
- Department of Pharmaceutical Sciences, Northeastern University, Boston, MA, USA
| | - Tal Buki
- Laboratory of Structural Physiology, Department of Physiology & Pharmacology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Asher Peretz
- Department of Physiology & Pharmacology, Sackler Faculty of Medicine and Sagol School of Neurosciences, Tel Aviv University, Tel Aviv, Israel
| | - Milit Marom
- Laboratory of Structural Physiology, Department of Physiology & Pharmacology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Yoni Haitin
- Laboratory of Structural Physiology, Department of Physiology & Pharmacology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | | | - Joel A. Hirsch
- Department of Biochemistry & Molecular Biology, George S. Wise Faculty of Life Sciences, Institute of Structural Biology, Tel Aviv University, Tel Aviv, Israel
| | - Bernard Attali
- Department of Physiology & Pharmacology, Sackler Faculty of Medicine and Sagol School of Neurosciences, Tel Aviv University, Tel Aviv, Israel
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Narukawa M, Kurokawa A, Kohta R, Misaka T. Participation of the peripheral taste system in aging-dependent changes in taste sensitivity. Neuroscience 2017; 358:249-260. [PMID: 28687314 DOI: 10.1016/j.neuroscience.2017.06.054] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2017] [Revised: 06/27/2017] [Accepted: 06/28/2017] [Indexed: 11/19/2022]
Abstract
Previous studies have shown that aging modifies taste sensitivity. However, the factors affecting the changes in taste sensitivity remain unclear. To investigate the cause of the age-related changes in taste sensitivity, we compared the peripheral taste detection systems in young and old mice. First, we examined whether taste sensitivity varied according to age using behavioral assays. We confirmed that the taste sensitivities to salty and bitter tastes decreased with aging. In other assays, the gustatory nerve responses to salty and sweet tastes increased significantly with aging, while those to bitter taste did not change. Thus, the profile of the gustatory nerve responses was inconsistent with the profile of the behavioral responses. Next, we evaluated the expressions of taste-related molecules in the taste buds. Although no apparent differences in the expressions of representative taste receptors were observed between the two age groups, the mRNA expressions of signaling effectors were slightly, but significantly, decreased in old mice. No significant differences in the turnover rates of taste bud cells were observed between the two age groups. Thus, we did not observe any large decreases in the expressions of taste-related molecules and turnover rates of taste bud cells with aging. Based on these findings, we conclude that changes in taste sensitivity with aging were not caused by aging-related degradation of peripheral taste organs. Meanwhile, the concentrations of several serum components that modify taste responses changed with age. Thus, taste signal-modifying factors such as serum components may have a contributing role in aging-related changes in taste sensitivity.
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Affiliation(s)
- Masataka Narukawa
- Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
| | - Azusa Kurokawa
- Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
| | - Rie Kohta
- Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
| | - Takumi Misaka
- Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo-ku, Tokyo, Japan.
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40
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Wang Y, Zhao Y, Zhang J, Yang Y, Liu F. A case of a novel mutation in HNF1β-related maturity-onset diabetes of the young type 5 with diabetic kidney disease complication in a Chinese family. J Diabetes Complications 2017; 31:1243-1246. [PMID: 28502589 DOI: 10.1016/j.jdiacomp.2016.11.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/28/2016] [Revised: 11/08/2016] [Accepted: 11/09/2016] [Indexed: 02/05/2023]
Abstract
AIMS Precise diagnosis of maturity-onset diabetes of the young (MODY) has proven valuable for understanding mechanism of diabetes and selecting optimal therapy. A proband and her mother with diabetic kidney disease (DKD) were studied to investigate potential genes responsible for diabetes and different severity of DKD between the parent and offspring. METHODS The family with suspected MODY underwent mutational analyses by the whole exome sequencing (WES). Candidate pathogenic variants were validated by Sanger sequencing and tested for co-segregation. The clinical parameters of subjects were collected from medical records. RESULTS A novel missense heterozygous mutation in exon 4 of the hepatocyte nuclear factor 1β (HNF1β), c.1007A > G (p.H336R), was identified in both the proband and her mother. Moreover, comparing the family's WES results, we found that the proband had acquired a KCNQ1 gene mutation from her father and acquired ACE and SORBS1 gene mutations from her mother. These three genes are known susceptibility genes of DKD and may impose additional effects contributing to DKD severity. CONCLUSIONS A novel mutation in HNF1β-MODY was identified in a Chinese family complicated with DKD, and the additional effect of pathogenic variants in susceptibility genes was speculated to contribute to DKD severity.
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Affiliation(s)
- Yiting Wang
- Division of Nephrology, West China Hospital of Sichuan University, Chengdu 610041, Sichuan, China
| | - Yingwang Zhao
- Division of Nephrology, West China Hospital of Sichuan University, Chengdu 610041, Sichuan, China
| | - Junlin Zhang
- Division of Nephrology, West China Hospital of Sichuan University, Chengdu 610041, Sichuan, China
| | - Yuxiang Yang
- Division of Nephrology, West China Hospital of Sichuan University, Chengdu 610041, Sichuan, China
| | - Fang Liu
- Division of Nephrology, West China Hospital of Sichuan University, Chengdu 610041, Sichuan, China.
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Kroncke BM, Van Horn WD, Smith J, Kang C, Welch RC, Song Y, Nannemann DP, Taylor KC, Sisco NJ, George AL, Meiler J, Vanoye CG, Sanders CR. Structural basis for KCNE3 modulation of potassium recycling in epithelia. Sci Adv 2016; 2:e1501228. [PMID: 27626070 PMCID: PMC5017827 DOI: 10.1126/sciadv.1501228] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2015] [Accepted: 08/10/2016] [Indexed: 05/25/2023]
Abstract
The single-span membrane protein KCNE3 modulates a variety of voltage-gated ion channels in diverse biological contexts. In epithelial cells, KCNE3 regulates the function of the KCNQ1 potassium ion (K(+)) channel to enable K(+) recycling coupled to transepithelial chloride ion (Cl(-)) secretion, a physiologically critical cellular transport process in various organs and whose malfunction causes diseases, such as cystic fibrosis (CF), cholera, and pulmonary edema. Structural, computational, biochemical, and electrophysiological studies lead to an atomically explicit integrative structural model of the KCNE3-KCNQ1 complex that explains how KCNE3 induces the constitutive activation of KCNQ1 channel activity, a crucial component in K(+) recycling. Central to this mechanism are direct interactions of KCNE3 residues at both ends of its transmembrane domain with residues on the intra- and extracellular ends of the KCNQ1 voltage-sensing domain S4 helix. These interactions appear to stabilize the activated "up" state configuration of S4, a prerequisite for full opening of the KCNQ1 channel gate. In addition, the integrative structural model was used to guide electrophysiological studies that illuminate the molecular basis for how estrogen exacerbates CF lung disease in female patients, a phenomenon known as the "CF gender gap."
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Affiliation(s)
- Brett M. Kroncke
- Department of Biochemistry, Vanderbilt University, Nashville, TN 37240, USA
- Center for Structural Biology, Vanderbilt University, Nashville, TN 37240, USA
| | - Wade D. Van Horn
- Department of Biochemistry, Vanderbilt University, Nashville, TN 37240, USA
- Center for Structural Biology, Vanderbilt University, Nashville, TN 37240, USA
- School of Molecular Sciences, Arizona State University, Tempe, AZ 85287, USA
- Biodesign Institute, Arizona State University, Tempe, AZ 85287, USA
- Center for Personalized Diagnostics, Arizona State University, Tempe, AZ 85287, USA
| | - Jarrod Smith
- Department of Biochemistry, Vanderbilt University, Nashville, TN 37240, USA
- Center for Structural Biology, Vanderbilt University, Nashville, TN 37240, USA
| | - CongBao Kang
- Department of Biochemistry, Vanderbilt University, Nashville, TN 37240, USA
- Center for Structural Biology, Vanderbilt University, Nashville, TN 37240, USA
- Experimental Therapeutics Centre, Agency for Science Technology and Research, Singapore, Singapore
| | - Richard C. Welch
- Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37240, USA
| | - Yuanli Song
- Department of Biochemistry, Vanderbilt University, Nashville, TN 37240, USA
- Center for Structural Biology, Vanderbilt University, Nashville, TN 37240, USA
| | - David P. Nannemann
- Center for Structural Biology, Vanderbilt University, Nashville, TN 37240, USA
- Department of Chemistry, Vanderbilt University, Nashville, TN 37235, USA
| | - Keenan C. Taylor
- Department of Biochemistry, Vanderbilt University, Nashville, TN 37240, USA
- Center for Structural Biology, Vanderbilt University, Nashville, TN 37240, USA
| | - Nicholas J. Sisco
- School of Molecular Sciences, Arizona State University, Tempe, AZ 85287, USA
- Biodesign Institute, Arizona State University, Tempe, AZ 85287, USA
- Center for Personalized Diagnostics, Arizona State University, Tempe, AZ 85287, USA
| | - Alfred L. George
- Department of Pharmacology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Jens Meiler
- Center for Structural Biology, Vanderbilt University, Nashville, TN 37240, USA
- Department of Chemistry, Vanderbilt University, Nashville, TN 37235, USA
| | - Carlos G. Vanoye
- Department of Pharmacology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Charles R. Sanders
- Department of Biochemistry, Vanderbilt University, Nashville, TN 37240, USA
- Center for Structural Biology, Vanderbilt University, Nashville, TN 37240, USA
- Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37240, USA
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Chen J, Yao ZX, Chen JS, Gi YJ, Muñoz NM, Kundra S, Herlong HF, Jeong YS, Goltsov A, Ohshiro K, Mistry NA, Zhang J, Su X, Choufani S, Mitra A, Li S, Mishra B, White J, Rashid A, Wang AY, Javle M, Davila M, Michaely P, Weksberg R, Hofstetter WL, Finegold MJ, Shay JW, Machida K, Tsukamoto H, Mishra L. TGF-β/β2-spectrin/CTCF-regulated tumor suppression in human stem cell disorder Beckwith-Wiedemann syndrome. J Clin Invest 2016; 126:527-42. [PMID: 26784546 DOI: 10.1172/jci80937] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2015] [Accepted: 11/30/2015] [Indexed: 12/19/2022] Open
Abstract
Beckwith-Wiedemann syndrome (BWS) is a human stem cell disorder, and individuals with this disease have a substantially increased risk (~800-fold) of developing tumors. Epigenetic silencing of β2-spectrin (β2SP, encoded by SPTBN1), a SMAD adaptor for TGF-β signaling, is causally associated with BWS; however, a role of TGF-β deficiency in BWS-associated neoplastic transformation is unexplored. Here, we have reported that double-heterozygous Sptbn1+/- Smad3+/- mice, which have defective TGF-β signaling, develop multiple tumors that are phenotypically similar to those of BWS patients. Moreover, tumorigenesis-associated genes IGF2 and telomerase reverse transcriptase (TERT) were overexpressed in fibroblasts from BWS patients and TGF-β-defective mice. We further determined that chromatin insulator CCCTC-binding factor (CTCF) is TGF-β inducible and facilitates TGF-β-mediated repression of TERT transcription via interactions with β2SP and SMAD3. This regulation was abrogated in TGF-β-defective mice and BWS, resulting in TERT overexpression. Imprinting of the IGF2/H19 locus and the CDKN1C/KCNQ1 locus on chromosome 11p15.5 is mediated by CTCF, and this regulation is lost in BWS, leading to aberrant overexpression of growth-promoting genes. Therefore, we propose that loss of CTCF-dependent imprinting of tumor-promoting genes, such as IGF2 and TERT, results from a defective TGF-β pathway and is responsible at least in part for BWS-associated tumorigenesis as well as sporadic human cancers that are frequently associated with SPTBN1 and SMAD3 mutations.
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Egashira T, Yuasa S, Tohyama S, Kuroda Y, Suzuki T, Seki T, Fukuda K. Patient-Specific Induced Pluripotent Stem Cell Models: Characterization of iPS Cell-Derived Cardiomyocytes. Methods Mol Biol 2016; 1353:343-353. [PMID: 25520287 DOI: 10.1007/7651_2014_165] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Despite significant advances in medical treatment, cardiovascular disease is still a major cause of morbidity and mortality in advanced countries. To improve the outcome, the further promotion of basic cardiovascular science has a pivotal role for the developing novel therapeutic approach. However, due to the inaccessibility of human heart tissue, we couldn't obtain the sufficient amount of patient's heart tissues. The discovery of human-induced pluripotent stem cells (iPSCs) is highly expected to provide the breakthrough to this obstruction. Through the patient-specific iPSCs-derived cardiomyocytes, we could analyze the patient-specific heart diseases directly and repetitively. Herein we introduce the outline of creation for cardiac disease modeling using patient-specific iPSCs. Within several topics, we present the actual representative methodologies throughout the process from the derivation of cardiomyocytes to those of functional analysis.
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Affiliation(s)
- Toru Egashira
- Department of Cardiology, Keio University School of Medicine, 35-Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan
| | - Shinsuke Yuasa
- Department of Cardiology, Keio University School of Medicine, 35-Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan.
| | - Shugo Tohyama
- Department of Cardiology, Keio University School of Medicine, 35-Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan
| | - Yusuke Kuroda
- Department of Cardiovascular Research, Research Institute of Environmental Medicine, Nagoya University, Aichi, Japan
| | - Tomoyuki Suzuki
- Department of Cardiovascular Research, Research Institute of Environmental Medicine, Nagoya University, Aichi, Japan
| | - Tomohisa Seki
- Department of Cardiology, Keio University School of Medicine, 35-Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan
| | - Keiichi Fukuda
- Department of Cardiology, Keio University School of Medicine, 35-Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan
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Elvira B, Warsi J, Fezai M, Munoz C, Lang F. SPAK and OSR1 Sensitive Cell Membrane Protein Abundance and Activity of KCNQ1/E1 K+ Channels. Cell Physiol Biochem 2015; 37:2032-42. [PMID: 26584301 DOI: 10.1159/000438563] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/03/2015] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND/AIMS KCNQ1/E1 channels are expressed in diverse tissues and serve a variety of functions including endolymph secretion in the inner ear, cardiac repolarization, epithelial transport and cell volume regulation. Kinases involved in regulation of epithelial transport and cell volume include SPAK (SPS1-related proline/alanine-rich kinase) and OSR1 (oxidative stress-responsive kinase 1), which are under control of WNK (with-no-K[Lys]) kinases. The present study explored whether KCNQ1/E1 channels are regulated by SPAK and/or OSR1. METHODS cRNA encoding KCNQ1/E1 was injected into Xenopus oocytes with or without additional injection of cRNA encoding wild-type SPAK, constitutively active T233ESPAK, WNK insensitive T233ASPAK, catalytically inactive D212ASPAK, wild-type OSR1, constitutively active T185EOSR1, WNK insensitive T185AOSR1 and catalytically inactive D164AOSR1. Voltage gated K+ channel activity was quantified utilizing dual electrode voltage clamp and KCNQ1/E1 channel protein abundance in the cell membrane utilizing chemiluminescence of KCNQ1/E1 containing an extracellular Flag tag epitope (KCNQ1-Flag/E1). RESULTS KCNQ1/E1 activity and KCNQ1-Flag/E1 protein abundance were significantly enhanced by wild-type SPAK and T233ESPAK, but not by T233ASPAK and D212ASPAK. Similarly, KCNQ1/E1 activity and KCNQ1-Flag/E1 protein abundance were significantly increased by wild-type OSR1 and T185EOSR1, but not by T185AOSR1 and D164AOSR1. CONCLUSIONS SPAK and OSR1 participate in the regulation of KCNQ1/E1 protein abundance and activity.
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Cazals Y, Bévengut M, Zanella S, Brocard F, Barhanin J, Gestreau C. KCNK5 channels mostly expressed in cochlear outer sulcus cells are indispensable for hearing. Nat Commun 2015; 6:8780. [PMID: 26549439 PMCID: PMC4659937 DOI: 10.1038/ncomms9780] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2015] [Accepted: 10/01/2015] [Indexed: 01/03/2023] Open
Abstract
In the cochlea, K(+) is essential for mechano-electrical transduction. Here, we explore cochlear structure and function in mice lacking K(+) channels of the two-pore domain family. A profound deafness associated with a decrease in endocochlear potential is found in adult Kcnk5(-/-) mice. Hearing occurs around postnatal day 19 (P19), and completely disappears 2 days later. At P19, Kcnk5(-/-) mice have a normal endolymphatic [K(+)] but a partly lowered endocochlear potential. Using Lac-Z as a gene reporter, KCNK5 is mainly found in outer sulcus Claudius', Boettcher's and root cells. Low levels of expression are also seen in the spiral ganglion, Reissner's membrane and stria vascularis. Essential channels (KCNJ10 and KCNQ1) contributing to K(+) secretion in stria vascularis have normal expression in Kcnk5(-/-) mice. Thus, KCNK5 channels are indispensable for the maintenance of hearing. Among several plausible mechanisms, we emphasize their role in K(+) recycling along the outer sulcus lateral route.
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Affiliation(s)
- Yves Cazals
- Laboratoire de Neurosciences Intégratives et Adaptatives (UMR7260), Fédération de Recherche 3C (Cerveau, Comportement, Cognition), Aix-Marseille-Université and CNRS, Marseille 13331, France
| | - Michelle Bévengut
- Centre de Recherche en Neurobiologie et Neurophysiologie de Marseille (UMR7286), Aix-Marseille-Université and CNRS, Marseille 13344, France
| | - Sébastien Zanella
- Centre de Recherche en Neurobiologie et Neurophysiologie de Marseille (UMR7286), Aix-Marseille-Université and CNRS, Marseille 13344, France
- Institut de Neurosciences de la Timone (UMR7289), Aix-Marseille Université and CNRS, Marseille 13005, France
| | - Frédéric Brocard
- Institut de Neurosciences de la Timone (UMR7289), Aix-Marseille Université and CNRS, Marseille 13005, France
| | - Jacques Barhanin
- Laboratoire de Physio-Médecine Moléculaire (UMR7370), Université de Nice-Sophia Antipolis and CNRS, Nice 06107, France
- Laboratories of Excellence, Ion Channel Science and Therapeutics, France
| | - Christian Gestreau
- Centre de Recherche en Neurobiologie et Neurophysiologie de Marseille (UMR7286), Aix-Marseille-Université and CNRS, Marseille 13344, France
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46
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Sachyani D, Dvir M, Strulovich R, Tria G, Tobelaim W, Peretz A, Pongs O, Svergun D, Attali B, Hirsch JA. Structural basis of a Kv7.1 potassium channel gating module: studies of the intracellular c-terminal domain in complex with calmodulin. Structure 2015; 22:1582-94. [PMID: 25441029 DOI: 10.1016/j.str.2014.07.016] [Citation(s) in RCA: 76] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2013] [Revised: 07/03/2014] [Accepted: 07/17/2014] [Indexed: 01/13/2023]
Abstract
Kv7 channels tune neuronal and cardiomyocyte excitability. In addition to the channel membrane domain, they also have a unique intracellular C-terminal (CT) domain, bound constitutively to calmodulin (CaM). This CT domain regulates gating and tetramerization. We investigated the structure of the membrane proximal CT module in complex with CaM by X-ray crystallography. The results show how the CaM intimately hugs a two-helical bundle, explaining many channelopathic mutations. Structure-based mutagenesis of this module in the context of concatemeric tetramer channels and functional analysis along with in vitro data lead us to propose that one CaM binds to one individual protomer, without crosslinking subunits and that this configuration is required for proper channel expression and function. Molecular modeling of the CT/CaM complex in conjunction with small-angle X-ray scattering suggests that the membrane proximal region, having a rigid lever arm, is a critical gating regulator.
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Hu Y, Chen J, Wang B, Yang W, Zhang C, Hu J, Xie Z, Cao Z, Li W, Wu Y, Chen Z. Engineering a peptide inhibitor towards the KCNQ1/KCNE1 potassium channel (IKs). Peptides 2015; 71:77-83. [PMID: 26188173 DOI: 10.1016/j.peptides.2015.07.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/10/2015] [Revised: 07/05/2015] [Accepted: 07/07/2015] [Indexed: 11/27/2022]
Abstract
The KCNQ1/KCNE1 channel (IKs) plays important roles in the physiological and pathological process of heart, but no potent peptide acting on this channel has been reported. In this work, we found that the natural scorpion venom hardly inhibited KCNQ1/KCNE1 channel currents. Based on this observation, we attempted to use three natural scorpion toxins ChTX, BmKTX and OmTx2 with two different structural folds as templates to engineer potent peptide inhibitors towards the KCNQ1/KCNE1 channel. Pharmacological experiments showed that when we screen with 1μM MT2 peptide, an analog derived from BmKTX toxin, KCNQ1/KCNE1 channel currents could be effectively inhibited. Concentration-dependent experiments showed that MT2 inhibited the KCNQ1/KCNE1 channel with an IC50 value of 4.6±1.9μM. The mutagenesis experiments indicated that MT2 peptide likely used Lys26 residue to interact with the KCNQ1/KCNE1 channel. With MT2 as a new template, we further designed a more potent MT2-2 peptide, which selectively inhibited the KCNQ1/KCNE1 channel with an IC50 of 1.51±0.62μM. Together, this work provided a much potent KCNQ1/KCNE1 channel peptide inhibitor so far, and highlighted the role of molecular strategy in developing potent peptide inhibitors for the natural toxin-insensitive orphan receptors.
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Affiliation(s)
- Youtian Hu
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan 430072, China
| | - Jing Chen
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan 430072, China
| | - Bin Wang
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan 430072, China
| | - Weishan Yang
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan 430072, China
| | - Chuangeng Zhang
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan 430072, China
| | - Jun Hu
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan 430072, China
| | - Zili Xie
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan 430072, China
| | - Zhijian Cao
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan 430072, China; Center for BioDrug Research, Wuhan University, Wuhan 430072, China
| | - Wenxin Li
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan 430072, China; Center for BioDrug Research, Wuhan University, Wuhan 430072, China
| | - Yingliang Wu
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan 430072, China; Center for BioDrug Research, Wuhan University, Wuhan 430072, China.
| | - Zongyun Chen
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan 430072, China; Department of Biochemistry and Molecular Biology, Institute of Basic Medical Sciences, Hubei University of Medicine, Hubei, China.
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Kienitz MC, Vladimirova D. Synergistic modulation of KCNQ1/KCNE1 K(+) channels (IKs) by phosphatidylinositol 4,5-bisphosphate (PIP2) and [ATP]i. Cell Signal 2015; 27:1457-68. [PMID: 25892084 DOI: 10.1016/j.cellsig.2015.04.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2015] [Accepted: 04/08/2015] [Indexed: 01/01/2023]
Abstract
Cardiac KCNQ1/KCNE1 channels (IKs) are dependent on the concentration of membrane phosphatidylinositol-4,5-bisphosphate (PIP2) and on cytosolic ATP by two distinct mechanisms. In this study we measured IKs and FRET between PH-PLCδ-based fluorescent PIP2 sensors in a stable KCNQ1/KCNE1 CHO cell line. Effects of activating either a muscarinic M3 receptor or the switchable phosphatase Ci-VSP on IKs were analyzed. Recovery of IKs from inhibition induced by muscarinic stimulation was incomplete despite full PIP2 resynthesis. Recovery of IKs was completely suppressed under ATP-free conditions, but partially restored by the ATP analog AMP-PCP, providing evidence that depletion of intracellular ATP inhibits IKs independent of PIP2-depletion. Simultaneous patch-clamp and FRET measurements in cells co-expressing Ci-VSP and the PIP2-FRET sensor revealed a component of IKs inhibition directly related to dynamic PIP2-depletion. A second component of inhibition was independent of acute changes in PIP2 and could be mimicked by ATP-free pipette solution, suggesting that it results from intracellular ATP-depletion. The reduction of intracellular ATP upon Ci-VSP activation appears to be independent of its activity as a phosphoinositide phosphatase. Our data demonstrate that ATP-depletion slowed IKs activation but had no short-term effect on PIP2 regeneration, suggesting that impaired PIP2-resynthesis cannot account for the rapid IKs inhibition by ATP-depletion. Furthermore, the second component of IKs inhibition by Ci-VSP was reduced by AMP-PCP in the pipette filling solution, indicating that direct binding of ATP to the KCNQ1/KCNE1 complex is required for voltage activation of IKs. We suggest that fluctuations of the cellular metabolic state regulate IKs in parallel with Gq-coupled PLC activation and PIP2-depletion.
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Fan Z, Li W, Lee SR, Meng Q, Shi B, Bunch TD, White KL, Kong IK, Wang Z. Efficient gene targeting in golden Syrian hamsters by the CRISPR/Cas9 system. PLoS One 2014; 9:e109755. [PMID: 25299451 PMCID: PMC4192357 DOI: 10.1371/journal.pone.0109755] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2014] [Accepted: 09/04/2014] [Indexed: 12/24/2022] Open
Abstract
The golden Syrian hamster is the model of choice or the only rodent model for studying many human diseases. However, the lack of gene targeting tools in hamsters severely limits their use in biomedical research. Here, we report the first successful application of the CRISPR/Cas9 system to efficiently conduct gene targeting in hamsters. We designed five synthetic single-guide RNAs (sgRNAs)--three for targeting the coding sequences for different functional domains of the hamster STAT2 protein, one for KCNQ1, and one for PPP1R12C--and demonstrated that the CRISPR/Cas9 system is highly efficient in introducing site-specific mutations in hamster somatic cells. We then developed unique pronuclear (PN) and cytoplasmic injection protocols in hamsters and produced STAT2 knockout (KO) hamsters by injecting the sgRNA/Cas9, either in the form of plasmid or mRNA, targeting exon 4 of hamster STAT2. Among the produced hamsters, 14.3% and 88.9% harbored germline-transmitted STAT2 mutations from plasmid and mRNA injection, respectively. Notably, 10.4% of the animals produced from mRNA injection were biallelically targeted. This is the first success in conducting site-specific gene targeting in hamsters and can serve as the foundation for developing other genetically engineered hamster models for human disease.
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Affiliation(s)
- Zhiqiang Fan
- Department of Animal, Dairy, and Veterinary Sciences, Utah State University, Logan, Utah, United States of America
| | - Wei Li
- Department of Animal, Dairy, and Veterinary Sciences, Utah State University, Logan, Utah, United States of America
| | - Sang R. Lee
- Department of Animal, Dairy, and Veterinary Sciences, Utah State University, Logan, Utah, United States of America
| | - Qinggang Meng
- Department of Animal, Dairy, and Veterinary Sciences, Utah State University, Logan, Utah, United States of America
| | - Bi Shi
- Department of Animal, Dairy, and Veterinary Sciences, Utah State University, Logan, Utah, United States of America
| | - Thomas D. Bunch
- Department of Animal, Dairy, and Veterinary Sciences, Utah State University, Logan, Utah, United States of America
| | - Kenneth L. White
- Department of Animal, Dairy, and Veterinary Sciences, Utah State University, Logan, Utah, United States of America
| | - Il-Keun Kong
- Department of Animal Science, Division of Applied Life Science, Gyeongsang National University, Jinju, Gyeongnam Province, Republic of Korea
- Institute of Agriculture and Life Science, Gyeongsang National University, Jinju, Gyeongnam Province, Republic of Korea
| | - Zhongde Wang
- Department of Animal, Dairy, and Veterinary Sciences, Utah State University, Logan, Utah, United States of America
- Auratus Bio, LLC., Canton, South Dakota, United States of America
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50
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Choi SH, Lee BH, Kim HJ, Jung SW, Kim HS, Shin HC, Lee JH, Kim HC, Rhim H, Hwang SH, Ha TS, Kim HJ, Cho H, Nah SY. Ginseng gintonin activates the human cardiac delayed rectifier K+ channel: involvement of Ca2+/calmodulin binding sites. Mol Cells 2014; 37:656-63. [PMID: 25234465 PMCID: PMC4179134 DOI: 10.14348/molcells.2014.0087] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2014] [Revised: 07/25/2014] [Accepted: 08/11/2014] [Indexed: 02/07/2023] Open
Abstract
Gintonin, a novel, ginseng-derived G protein-coupled lysophosphatidic acid (LPA) receptor ligand, elicits [Ca(2+)]i transients in neuronal and non-neuronal cells via pertussis toxin-sensitive and pertussis toxin-insensitive G proteins. The slowly activating delayed rectifier K(+) (I(Ks)) channel is a cardiac K(+) channel composed of KCNQ1 and KCNE1 subunits. The C terminus of the KCNQ1 channel protein has two calmodulin-binding sites that are involved in regulating I(Ks) channels. In this study, we investigated the molecular mechanisms of gintonin-mediated activation of human I(Ks) channel activity by expressing human I(Ks) channels in Xenopus oocytes. We found that gintonin enhances IKs channel currents in concentration- and voltage-dependent manners. The EC50 for the I(Ks) channel was 0.05 ± 0.01 μg/ml. Gintonin-mediated activation of the I(Ks) channels was blocked by an LPA1/3 receptor antagonist, an active phospholipase C inhibitor, an IP3 receptor antagonist, and the calcium chelator BAPTA. Gintonin-mediated activation of both the I(Ks) channel was also blocked by the calmodulin (CaM) blocker calmidazolium. Mutations in the KCNQ1 [Ca(2+)]i/CaM-binding IQ motif sites (S373P, W392R, or R539W)blocked the action of gintonin on I(Ks) channel. However, gintonin had no effect on hERG K(+) channel activity. These results show that gintonin-mediated enhancement of I(Ks) channel currents is achieved through binding of the [Ca(2+)]i/CaM complex to the C terminus of KCNQ1 subunit.
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Affiliation(s)
- Sun-Hye Choi
- Department of Physiology, College of Veterinary Medicine and Bio/Molecular Informatics Center, Konkuk University, Seoul 143-701, Korea
| | - Byung-Hwan Lee
- Department of Physiology, College of Veterinary Medicine and Bio/Molecular Informatics Center, Konkuk University, Seoul 143-701, Korea
| | - Hyeon-Joong Kim
- Department of Physiology, College of Veterinary Medicine and Bio/Molecular Informatics Center, Konkuk University, Seoul 143-701, Korea
| | - Seok-Won Jung
- Department of Physiology, College of Veterinary Medicine and Bio/Molecular Informatics Center, Konkuk University, Seoul 143-701, Korea
| | - Hyun-Sook Kim
- Department of Physiology, College of Veterinary Medicine and Bio/Molecular Informatics Center, Konkuk University, Seoul 143-701, Korea
| | - Ho-Chul Shin
- Department of Pharmacology and Toxicology, College of Veterinary Medicine, Konkuk University, Seoul 143-701, Korea
| | - Jun-Hee Lee
- Department of Physical Therapy, College of Health Science, Cheongju University, Cheongju 360-764, Korea
| | - Hyoung-Chun Kim
- Neuropsychopharmacology and Toxicology Program, College of Pharmacy, Kangwon National University, Chuncheon 200-701, Korea
| | - Hyewhon Rhim
- Life Science Division, Korea Institute of Science and Technology, Seoul 136-791, Korea
| | - Sung-Hee Hwang
- Department of Pharmaceutical Engineering College of Health Sciences Sangji University, Wonju 220-702, Korea
| | - Tal soo Ha
- Department of Biomedical Science, Daegu University, Gyeonsan 712-714, Korea
| | - Hyun-Ji Kim
- Department of Physiology and Samsung Biomedical Research Institute, School of Medicine, Sungkyunkwan University, Suwon 440-746, Korea
| | - Hana Cho
- Department of Physiology and Samsung Biomedical Research Institute, School of Medicine, Sungkyunkwan University, Suwon 440-746, Korea
| | - Seung-Yeol Nah
- Department of Physiology, College of Veterinary Medicine and Bio/Molecular Informatics Center, Konkuk University, Seoul 143-701, Korea
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