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The voltage-gated channel accessory protein KCNE2: multiple ion channel partners, multiple ways to long QT syndrome

Published online by Cambridge University Press:  14 December 2011

Jodene Eldstrom
Affiliation:
Department of Anesthesiology, Pharmacology and Therapeutics, University of British Columbia, Vancouver, BC, Canada
David Fedida*
Affiliation:
Department of Anesthesiology, Pharmacology and Therapeutics, University of British Columbia, Vancouver, BC, Canada
*
*Corresponding author: David Fedida, Department of Anesthesiology, Pharmacology and Therapeutics, University of British Columbia, 2176 Health Sciences Mall, Vancouver, BC, CanadaV6T 1Z3. E-mail: fedida@interchange.ubc.ca

Abstract

The single-pass transmembrane protein KCNE2 or MIRP1 was once thought to be the missing accessory protein that combined with hERG to fully recapitulate the cardiac repolarising current IKr. As a result of this role, it was an easy next step to associate mutations in KCNE2 to long QT syndrome, in which there is delayed repolarisation of the heart. Since that time however, KCNE2 has been shown to modify the behaviour of several other channels and currents, and its role in the heart and in the aetiology of long QT syndrome has become less clear. In this article, we review the known interactions of the KCNE2 protein and the resulting functional effects, and the effects of mutations in KCNE2 and their clinical role.

Type
Review Article
Copyright
Copyright © Cambridge University Press 2011

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References

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Further reading, resources and contacts

Kaufman, E.S. (2011) Arrhythmic risk in congenital long QT syndrome. Journal of Electrocardiology 44, 645-649CrossRefGoogle ScholarPubMed
Pongs, O. and Schwarz, J.R. (2010) Ancillary subunits associated with voltage-dependent K+ channels. Physiological Reviews 90, 755-796CrossRefGoogle ScholarPubMed
The Gene Connection for the Heart website maintains a list of mutations and SNPs associated with inherited arrhythmias as well as their location in the protein, associated phenotype and links to articles where mutants are published:http://www.fsm.it/cardmoc/Google Scholar
The QT Drug Lists by Risk Groups lists QT prolonging drugs including their risk for causing Torsades de Points:http://www.azcert.org/medical-pros/drug-lists/drug-lists.cfmGoogle Scholar
The Leiden Open (source) Variation Database (LOVD), locus-specific database list has the stated aim to ‘provide a flexible, freely available tool for Gene-centered collection and display of DNA variations’. Sites tracking LQTS gene mutations can be found here:http://grenada.lumc.nl/LSDB_list/lsdb.php?action=view_allGoogle Scholar
Kaufman, E.S. (2011) Arrhythmic risk in congenital long QT syndrome. Journal of Electrocardiology 44, 645-649CrossRefGoogle ScholarPubMed
Pongs, O. and Schwarz, J.R. (2010) Ancillary subunits associated with voltage-dependent K+ channels. Physiological Reviews 90, 755-796CrossRefGoogle ScholarPubMed
The Gene Connection for the Heart website maintains a list of mutations and SNPs associated with inherited arrhythmias as well as their location in the protein, associated phenotype and links to articles where mutants are published:http://www.fsm.it/cardmoc/Google Scholar
The QT Drug Lists by Risk Groups lists QT prolonging drugs including their risk for causing Torsades de Points:http://www.azcert.org/medical-pros/drug-lists/drug-lists.cfmGoogle Scholar
The Leiden Open (source) Variation Database (LOVD), locus-specific database list has the stated aim to ‘provide a flexible, freely available tool for Gene-centered collection and display of DNA variations’. Sites tracking LQTS gene mutations can be found here:http://grenada.lumc.nl/LSDB_list/lsdb.php?action=view_allGoogle Scholar