Channelpedia

K(V)LQT1 and lsK (minK) proteins associate to form the I(Ks) cardiac potassium current.


Authors: J Barhanin, F Lesage, E Guillemare, M Fink, M Lazdunski, G Romey

Journal, date & volume: Nature, 1996 Nov 7 , 384, 78-80

PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/8900282

Channelpedia reference in: KCNQ1 , Kv7.1

Abstract
In mammalian cardiac cells, a variety of transient or sustained K+ currents contribute to the repolarization of action potentials. There are two main components of the delayed-rectifier sustained K+ current, I(Kr) (rapid) and I(Ks), (slow). I(Kr) is the product of the gene HERG, which is altered in the long-QT syndrome, LQT2. A channel with properties similar to those of the I(Ks) channel is produced when the cardiac protein IsK is expressed in Xenopus oocytes. However, it is a small protein with a very unusual structure for a cation channel. The LQT1 gene is another gene associated with the LQT syndrome, a disorder that causes sudden death from ventricular arrhythmias. Here we report the cloning of the full-length mouse K(V)LQT1 complementary DNA and show that K(V)LQT1 associates with IsK to form the channel underlying the I(Ks) cardiac current, which is a target of class-III anti-arrhythmic drugs and is involved in the LQT1 syndrome.