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Molecular evidence for a role of Shaw (Kv3) potassium channel subunits in potassium currents of dog atrium.
Yue L
,
Wang Z
,
Rindt H
,
Nattel S
.
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We previously described an ultrarapid delayed rectifier current in dog atrial myocytes (IKur,d) with properties resembling currents reported for Kv3.1 channels in neural tissue; however, there was no direct molecular evidence for Shaw subfamily (Kv3) subunit expression in the heart. To identify the molecular basis of IKur,d, we cloned a full-length cDNA (dKv3.1) from canine atrium with homology-based reverse transcription (RT)- polymerase chain reaction (PCR) cloning techniques. A 1755 bp full-length cDNA (dKv3.1) was obtained, with 94.2 % homology to rat brainKv3.1 (rbKv3.1). The deduced amino acid sequence had 99.3 % homology with rbKv3.1. Heterologous expression of dKv3.1 in Xenopus oocytes produced currents with activation voltage dependence, rectification, and activation and deactivation kinetics that strongly resemble native IKur,d. Like IKur,d, dKv3.1 was found to be highly sensitive to extracellular 4-aminopyridine (4-AP) and tetraethylammonium (TEA). RNase protection assays, Western blots and immunohistochemical studies demonstrated the presence of dKv3.1 transcripts and proteins in dog atrial preparations and isolated canine atrial myocytes. Protein corresponding to the Kv1.5 subunit, which can also carry ultrarapid delayed rectifier current, was absent. Unlike neural tissues, which express two splice variants (Kv3.1a and Kv3.1b), canine atrium showed only Kv3.1b transcripts. Whole-cell patch-clamp studies showed that IKur,d is absent in canine ventricular myocytes, and immunohistochemical and Western blot analysis demonstrated the absence of dKv3.1 protein in canine ventricle. We conclude that the Shaw-type channel dKv3.1 is present in dog atrium, but not ventricle, and is the likely molecular basis of canine atrial IKur,d.
Abbott,
MiRP1 forms IKr potassium channels with HERG and is associated with cardiac arrhythmia.
1999, Pubmed,
Xenbase
Abbott,
MiRP1 forms IKr potassium channels with HERG and is associated with cardiac arrhythmia.
1999,
Pubmed
,
Xenbase
Barry,
Myocardial potassium channels: electrophysiological and molecular diversity.
1996,
Pubmed
Bou-Abboud,
Molecular correlates of the calcium-independent, depolarization-activated K+ currents in rat atrial myocytes.
1999,
Pubmed
Brahmajothi,
In situ hybridization reveals extensive diversity of K+ channel mRNA in isolated ferret cardiac myocytes.
1996,
Pubmed
Castellano,
Identification and functional characterization of a K+ channel alpha-subunit with regulatory properties specific to brain.
1997,
Pubmed
Deal,
Molecular physiology of cardiac potassium channels.
1996,
Pubmed
Dixon,
Role of the Kv4.3 K+ channel in ventricular muscle. A molecular correlate for the transient outward current.
1996,
Pubmed
Feng,
Antisense oligodeoxynucleotides directed against Kv1.5 mRNA specifically inhibit ultrarapid delayed rectifier K+ current in cultured adult human atrial myocytes.
1997,
Pubmed
Feng,
Ultrarapid delayed rectifier current inactivation in human atrial myocytes: properties and consequences.
1998,
Pubmed
,
Xenbase
Gan,
Cloning and characterization of the promoter for a potassium channel expressed in high frequency firing neurons.
1996,
Pubmed
Grissmer,
Pharmacological characterization of five cloned voltage-gated K+ channels, types Kv1.1, 1.2, 1.3, 1.5, and 3.1, stably expressed in mammalian cell lines.
1994,
Pubmed
Grissmer,
The Shaw-related potassium channel gene, Kv3.1, on human chromosome 11, encodes the type l K+ channel in T cells.
1992,
Pubmed
,
Xenbase
Harvey,
Recent studies on dendrotoxins and potassium ion channels.
1997,
Pubmed
Ho,
Pleiotropic effects of a disrupted K+ channel gene: reduced body weight, impaired motor skill and muscle contraction, but no seizures.
1997,
Pubmed
Hugnot,
Kv8.1, a new neuronal potassium channel subunit with specific inhibitory properties towards Shab and Shaw channels.
1996,
Pubmed
,
Xenbase
Jan,
Structural elements involved in specific K+ channel functions.
1992,
Pubmed
Klemic,
Inactivation of Kv2.1 potassium channels.
1998,
Pubmed
,
Xenbase
Li,
Adrenergic modulation of ultrarapid delayed rectifier K+ current in human atrial myocytes.
1996,
Pubmed
Luneau,
Alternative splicing contributes to K+ channel diversity in the mammalian central nervous system.
1991,
Pubmed
Mathie,
Voltage-activated potassium channels in mammalian neurons and their block by novel pharmacological agents.
1998,
Pubmed
Murakoshi,
Phosphorylation of the Kv2.1 K+ channel alters voltage-dependent activation.
1997,
Pubmed
Nattel,
Cardiac ultrarapid delayed rectifiers: a novel potassium current family o f functional similarity and molecular diversity.
1999,
Pubmed
Rettig,
Characterization of a Shaw-related potassium channel family in rat brain.
1992,
Pubmed
,
Xenbase
Ried,
Localization of a highly conserved human potassium channel gene (NGK2-KV4; KCNC1) to chromosome 11p15.
1993,
Pubmed
Rudy,
Contributions of Kv3 channels to neuronal excitability.
1999,
Pubmed
Salinas,
New modulatory alpha subunits for mammalian Shab K+ channels.
1997,
Pubmed
Sanguinetti,
Molecular physiology of cardiac delayed rectifier K+ channels.
1997,
Pubmed
Tempel,
Sequence of a probable potassium channel component encoded at Shaker locus of Drosophila.
1987,
Pubmed
Van Wagoner,
Outward K+ current densities and Kv1.5 expression are reduced in chronic human atrial fibrillation.
1997,
Pubmed
Wang,
Potential molecular basis of different physiological properties of the transient outward K+ current in rabbit and human atrial myocytes.
1999,
Pubmed
,
Xenbase
Xu,
Elimination of the transient outward current and action potential prolongation in mouse atrial myocytes expressing a dominant negative Kv4 alpha subunit.
1999,
Pubmed
Xu,
Attenuation of the slow component of delayed rectification, action potential prolongation, and triggered activity in mice expressing a dominant-negative Kv2 alpha subunit.
1999,
Pubmed
Yokoyama,
Potassium channels from NG108-15 neuroblastoma-glioma hybrid cells. Primary structure and functional expression from cDNAs.
1989,
Pubmed
,
Xenbase
Yue,
Characterization of an ultrarapid delayed rectifier potassium channel involved in canine atrial repolarization.
1996,
Pubmed
Yue,
Ionic remodeling underlying action potential changes in a canine model of atrial fibrillation.
1997,
Pubmed
Yue,
Adrenergic control of the ultrarapid delayed rectifier current in canine atrial myocytes.
1999,
Pubmed
Yue,
Molecular mechanisms underlying ionic remodeling in a dog model of atrial fibrillation.
1999,
Pubmed
