Click here to close
Hello! We notice that you are using Internet Explorer, which is not supported by Xenbase and may cause the site to display incorrectly.
We suggest using a current version of Chrome,
FireFox, or Safari.
Coupling the Cardiac Voltage-Gated Sodium Channel to Channelrhodopsin-2 Generates Novel Optical Switches for Action Potential Studies.
Vom Dahl C
,
Müller CE
,
Berisha X
,
Nagel G
,
Zimmer T
.
???displayArticle.abstract???
Voltage-gated sodium (Na+) channels respond to short membrane depolarization with conformational changes leading to pore opening, Na+ influx, and action potential (AP) upstroke. In the present study, we coupled channelrhodopsin-2 (ChR2), the key ion channel in optogenetics, directly to the cardiac voltage-gated Na+ channel (Nav1.5). Fusion constructs were expressed in Xenopus laevis oocytes, and electrophysiological recordings were performed by the two-microelectrode technique. Heteromeric channels retained both typical Nav1.5 kinetics and light-sensitive ChR2 properties. Switching to the current-clamp mode and applying short blue-light pulses resulted either in subthreshold depolarization or in a rapid change of membrane polarity typically seen in APs of excitable cells. To study the effect of individual K+ channels on the AP shape, we co-expressed either Kv1.2 or hERG with one of the Nav1.5-ChR2 fusions. As expected, both delayed rectifier K+ channels shortened AP duration significantly. Kv1.2 currents remarkably accelerated initial repolarization, whereas hERG channel activity efficiently restored the resting membrane potential. Finally, we investigated the effect of the LQT3 deletion mutant ΔKPQ on the AP shape and noticed an extremely prolonged AP duration that was directly correlated to the size of the non-inactivating Na+ current fraction. In conclusion, coupling of ChR2 to a voltage-gated Na+ channel generates optical switches that are useful for studying the effect of individual ion channels on the AP shape. Moreover, our novel optogenetic approach provides the potential for an application in pharmacology and optogenetic tissue-engineering.
Bean,
The action potential in mammalian central neurons.
2007, Pubmed
Bean,
The action potential in mammalian central neurons.
2007,
Pubmed
Bennett,
Molecular mechanism for an inherited cardiac arrhythmia.
1995,
Pubmed
,
Xenbase
Berndt,
High-efficiency channelrhodopsins for fast neuronal stimulation at low light levels.
2011,
Pubmed
Berndt,
OPTOGENETICS. Expanding the optogenetics toolkit.
2015,
Pubmed
Bi,
Ectopic expression of a microbial-type rhodopsin restores visual responses in mice with photoreceptor degeneration.
2006,
Pubmed
Blechschmidt,
Voltage-gated Na+ channel transcript patterns in the mammalian heart are species-dependent.
2008,
Pubmed
Boyden,
Millisecond-timescale, genetically targeted optical control of neural activity.
2005,
Pubmed
Catterall,
From ionic currents to molecular mechanisms: the structure and function of voltage-gated sodium channels.
2000,
Pubmed
Catterall,
Forty Years of Sodium Channels: Structure, Function, Pharmacology, and Epilepsy.
2017,
Pubmed
Chiamvimonvat,
Potassium currents in the heart: functional roles in repolarization, arrhythmia and therapeutics.
2017,
Pubmed
Deisseroth,
The form and function of channelrhodopsin.
2017,
Pubmed
Du,
18β-Glycyrrhetinic acid preferentially blocks late Na current generated by ΔKPQ Nav1.5 channels.
2012,
Pubmed
,
Xenbase
Feldbauer,
Channelrhodopsin-2 is a leaky proton pump.
2009,
Pubmed
Gellens,
Primary structure and functional expression of the human cardiac tetrodotoxin-insensitive voltage-dependent sodium channel.
1992,
Pubmed
,
Xenbase
Goldin,
Resurgence of sodium channel research.
2001,
Pubmed
Grandi,
Potassium channels in the heart: structure, function and regulation.
2017,
Pubmed
Grubb,
Channelrhodopsin-2 localised to the axon initial segment.
2010,
Pubmed
Gütter,
Characterization of N-terminally mutated cardiac Na(+) channels associated with long QT syndrome 3 and Brugada syndrome.
2013,
Pubmed
,
Xenbase
Hegemann,
From channelrhodopsins to optogenetics.
2013,
Pubmed
,
Xenbase
Hofherr,
Selective Golgi export of Kir2.1 controls the stoichiometry of functional Kir2.x channel heteromers.
2005,
Pubmed
Huang,
Structure-based assessment of disease-related mutations in human voltage-gated sodium channels.
2017,
Pubmed
Huang,
Y1767C, a novel SCN5A mutation, induces a persistent Na+ current and potentiates ranolazine inhibition of Nav1.5 channels.
2011,
Pubmed
Ishizuka,
Kinetic evaluation of photosensitivity in genetically engineered neurons expressing green algae light-gated channels.
2006,
Pubmed
Isom,
Sodium channel beta subunits: anything but auxiliary.
2001,
Pubmed
Kato,
Crystal structure of the channelrhodopsin light-gated cation channel.
2012,
Pubmed
Keating,
Molecular genetics of long QT syndrome.
1995,
Pubmed
Koopmann,
Functional differences of a Kv2.1 channel and a Kv2.1/Kv1.2S4-chimera are confined to a concerted voltage shift of various gating parameters.
1997,
Pubmed
,
Xenbase
Koopmann,
Role of the S2 and S3 segment in determining the activation kinetics in Kv2.1 channels.
2001,
Pubmed
,
Xenbase
Lee,
Interaction between voltage-gated sodium channels and the neurotoxin, tetrodotoxin.
2008,
Pubmed
Li,
Fast noninvasive activation and inhibition of neural and network activity by vertebrate rhodopsin and green algae channelrhodopsin.
2005,
Pubmed
Liman,
Subunit stoichiometry of a mammalian K+ channel determined by construction of multimeric cDNAs.
1992,
Pubmed
,
Xenbase
Nagel,
Channelrhodopsin-1: a light-gated proton channel in green algae.
2002,
Pubmed
,
Xenbase
Nagel,
Channelrhodopsin-2, a directly light-gated cation-selective membrane channel.
2003,
Pubmed
,
Xenbase
Nagel,
Light activation of channelrhodopsin-2 in excitable cells of Caenorhabditis elegans triggers rapid behavioral responses.
2005,
Pubmed
Nakano,
Genetics of long-QT syndrome.
2016,
Pubmed
Ng,
A massively parallel assay accurately discriminates between functionally normal and abnormal variants in a hotspot domain of KCNH2.
2022,
Pubmed
Nikolic,
Photocycles of channelrhodopsin-2.
2009,
Pubmed
Nuyens,
Abrupt rate accelerations or premature beats cause life-threatening arrhythmias in mice with long-QT3 syndrome.
2001,
Pubmed
Pal,
Voltage gated sodium channel inhibitors as anticonvulsant drugs: A systematic review on recent developments and structure activity relationship studies.
2021,
Pubmed
Papadatos,
Slowed conduction and ventricular tachycardia after targeted disruption of the cardiac sodium channel gene Scn5a.
2002,
Pubmed
Perry,
Getting to the heart of hERG K(+) channel gating.
2015,
Pubmed
Pérez-Riera,
The congenital long QT syndrome Type 3: An update.
2018,
Pubmed
Schneider,
Biophysics of Channelrhodopsin.
2015,
Pubmed
Shih,
Anatomy of the action potential in the heart.
1994,
Pubmed
Smith,
The inward rectification mechanism of the HERG cardiac potassium channel.
1996,
Pubmed
Stockklausner,
A sequence motif responsible for ER export and surface expression of Kir2.0 inward rectifier K(+) channels.
2001,
Pubmed
Stühmer,
Molecular basis of functional diversity of voltage-gated potassium channels in mammalian brain.
1989,
Pubmed
,
Xenbase
Subbiah,
Inherited cardiac arrhythmia syndromes: what have they taught us about arrhythmias and anti-arrhythmic therapy?
2004,
Pubmed
Surber,
Combination of cardiac conduction disease and long QT syndrome caused by mutation T1620K in the cardiac sodium channel.
2008,
Pubmed
,
Xenbase
Trudeau,
HERG, a human inward rectifier in the voltage-gated potassium channel family.
1995,
Pubmed
Ullrich,
Degradation of channelopsin-2 in the absence of retinal and degradation resistance in certain mutants.
2013,
Pubmed
Wallace,
Long QT Syndrome: Genetics and Future Perspective.
2019,
Pubmed
Walther,
Action potentials in Xenopus oocytes triggered by blue light.
2020,
Pubmed
,
Xenbase
Walzik,
Alternative splicing of the cardiac sodium channel creates multiple variants of mutant T1620K channels.
2011,
Pubmed
Wang,
A quantitative analysis of the activation and inactivation kinetics of HERG expressed in Xenopus oocytes.
1997,
Pubmed
,
Xenbase
Warmke,
A family of potassium channel genes related to eag in Drosophila and mammals.
1994,
Pubmed
Woodcock,
Cardiomyocytes structure, function and associated pathologies.
2005,
Pubmed
Yu,
Overview of the voltage-gated sodium channel family.
2003,
Pubmed
Yu,
Late sodium current associated cardiac electrophysiological and mechanical dysfunction.
2018,
Pubmed
Zimmer,
SCN5A channelopathies--an update on mutations and mechanisms.
2008,
Pubmed
Zimmer,
Functional expression of GFP-linked human heart sodium channel (hH1) and subcellular localization of the a subunit in HEK293 cells and dog cardiac myocytes.
2002,
Pubmed
Zimmer,
Mouse heart Na+ channels: primary structure and function of two isoforms and alternatively spliced variants.
2002,
Pubmed
