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Regulation of cardiac shal-related potassium channel Kv 4.3 by serum- and glucocorticoid-inducible kinase isoforms in Xenopus oocytes.
Baltaev R
,
Strutz-Seebohm N
,
Korniychuk G
,
Myssina S
,
Lang F
,
Seebohm G
.
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The human cardiac transient outward potassium current I(to) is formed by co-assembly of voltage-dependent K(+) channel (Kv 4.3) pore-forming alpha-subunits with differently spliced K channel interacting protein (KChIP) accessory proteins. I(to) is of considerable importance for the normal course of the cardiac ventricular action potential. The present study was performed to determine whether isoforms of the serum- and glucocorticoid-inducible kinase (SGK) family influence Kv 4.3/KChIP2b channel activity in the Xenopus laevis heterologous expression system. Co-expression of SGK1, but not of SGK2 or SGK3, increased Kv 4.3/KChIP2b channel currents. The up-regulation of the current was not due to changes in the activation curve or changes of channel inactivation. The currents in oocytes expressing Kv 4.3 alone were smaller than those in Kv 4.3/KChIP2b expressing oocytes, but were still stimulated by SGK1. The effect of wild-type SGK1 was mimicked by constitutively active SGK1 (SGK1 S422D) but not by an inactive mutant (SGK1 K127N). The current amplitude increase mediated by SGK1 was not dependent on NEDD4.2 or RAB5, nor did it reflect increased cell surface expression. In conclusion, SGK1 stimulates Kv 4.3 potassium channels expressed in Xenopus oocytes by a novel mechanism distinct from the known NEDD4.2-dependent pathway.
Aimond,
Ionic basis of ventricular arrhythmias in remodeled rat heart during long-term myocardial infarction.
1999, Pubmed
Aimond,
Ionic basis of ventricular arrhythmias in remodeled rat heart during long-term myocardial infarction.
1999,
Pubmed
An,
Modulation of A-type potassium channels by a family of calcium sensors.
2000,
Pubmed
,
Xenbase
Aomine,
Electrophysiological properties of ventricular muscle obtained from spontaneously diabetic mice.
2000,
Pubmed
Bosch,
Ionic mechanisms of electrical remodeling in human atrial fibrillation.
1999,
Pubmed
Brahmajothi,
Distinct transient outward potassium current (Ito) phenotypes and distribution of fast-inactivating potassium channel alpha subunits in ferret left ventricular myocytes.
1999,
Pubmed
Bähring,
Conserved Kv4 N-terminal domain critical for effects of Kv channel-interacting protein 2.2 on channel expression and gating.
2001,
Pubmed
Cerbai,
Ionic basis of action potential prolongation of hypertrophied cardiac myocytes isolated from hypertensive rats of different ages.
1994,
Pubmed
Decher,
Novel KChIP2 isoforms increase functional diversity of transient outward potassium currents.
2004,
Pubmed
,
Xenbase
Firestone,
Stimulus-dependent regulation of serum and glucocorticoid inducible protein kinase (SGK) transcription, subcellular localization and enzymatic activity.
2003,
Pubmed
Furukawa,
Differences in transient outward currents of feline endocardial and epicardial myocytes.
1990,
Pubmed
Greenstein,
Role of the calcium-independent transient outward current I(to1) in shaping action potential morphology and duration.
2000,
Pubmed
Guo,
Modulation of Kv4-encoded K(+) currents in the mammalian myocardium by neuronal calcium sensor-1.
2002,
Pubmed
Guo,
Effect of chronic hypoxia on ion channel development in cultured cardiac cells.
1995,
Pubmed
Hiraoka,
Calcium-sensitive and insensitive transient outward current in rabbit ventricular myocytes.
1989,
Pubmed
Huang,
Early down-regulation of K+ channel genes and currents in the postinfarction heart.
2000,
Pubmed
Kamiya,
Modulation of potassium channels by chronic hypoxia in neonatal rat cultured ventricular myocytes.
1997,
Pubmed
Kamynina,
Concerted action of ENaC, Nedd4-2, and Sgk1 in transepithelial Na(+) transport.
2002,
Pubmed
Kaprielian,
Relationship between K+ channel down-regulation and [Ca2+]i in rat ventricular myocytes following myocardial infarction.
1999,
Pubmed
Kuo,
A defect in the Kv channel-interacting protein 2 (KChIP2) gene leads to a complete loss of I(to) and confers susceptibility to ventricular tachycardia.
2001,
Pubmed
Kääb,
Molecular basis of transient outward potassium current downregulation in human heart failure: a decrease in Kv4.3 mRNA correlates with a reduction in current density.
1998,
Pubmed
Lang,
Regulation and physiological roles of serum- and glucocorticoid-induced protein kinase isoforms.
2001,
Pubmed
Lang,
Regulation of channels by the serum and glucocorticoid-inducible kinase - implications for transport, excitability and cell proliferation.
2003,
Pubmed
Li,
Effects of myocardial hypertrophy on transient outward current.
1994,
Pubmed
Libbus,
Electrotonic load triggers remodeling of repolarizing current Ito in ventricle.
2004,
Pubmed
Litovsky,
Clinicopathologic heterogeneity in hypertrophic cardiomyopathy with regard to age, asymmetric septal hypertrophy, and concentric hypertrophy beyond the pediatric age group.
1998,
Pubmed
Magyar,
Action potentials and potassium currents in rat ventricular muscle during experimental diabetes.
1992,
Pubmed
Mészáros,
Transient outward current in catecholamine-induced cardiac hypertrophy in the rat.
1996,
Pubmed
Patel,
Elucidating KChIP effects on Kv4.3 inactivation and recovery kinetics with a minimal KChIP2 isoform.
2002,
Pubmed
,
Xenbase
Pearce,
SGK1 regulation of epithelial sodium transport.
2003,
Pubmed
Pike,
Modification of the transient outward current of rat atrial myocytes by metabolic inhibition and oxidant stress.
1993,
Pubmed
Rosati,
Regulation of KChIP2 potassium channel beta subunit gene expression underlies the gradient of transient outward current in canine and human ventricle.
2001,
Pubmed
,
Xenbase
Sanguinetti,
When the KChIPs are down.
2002,
Pubmed
Seebohm,
Tight coupling of rubidium conductance and inactivation in human KCNQ1 potassium channels.
2003,
Pubmed
,
Xenbase
Tande,
Rate-dependent differences in dog epi- and endocardial monophasic action potential configuration in vivo.
1991,
Pubmed
Verrey,
SGK1: aldosterone-induced relay of Na+ transport regulation in distal kidney nephron cells.
2003,
Pubmed
,
Xenbase
Villmann,
Investigation by ion channel domain transplantation of rat glutamate receptor subunits, orphan receptors and a putative NMDA receptor subunit.
1999,
Pubmed
,
Xenbase
Volk,
Relationship between transient outward K+ current and Ca2+ influx in rat cardiac myocytes of endo- and epicardial origin.
1999,
Pubmed
Waldegger,
Cloning and characterization of a putative human serine/threonine protein kinase transcriptionally modified during anisotonic and isotonic alterations of cell volume.
1997,
Pubmed
Webster,
Characterization of sgk, a novel member of the serine/threonine protein kinase gene family which is transcriptionally induced by glucocorticoids and serum.
1993,
Pubmed
Yeola,
Electrophysiological and pharmacological correspondence between Kv4.2 current and rat cardiac transient outward current.
1997,
Pubmed
Yu,
Transient outward current, Ito1, is altered in cardiac memory.
1999,
Pubmed
