Background In heterologous expression systems, KCNE2 has been demonstrated to interact with

The cardiac delayed rectifier potassium current mediates repolarization of the action potential and underlies the QT interval of the ECG. Mutations in either of the two molecular components of the rapid delayed rectifier (I(K,r)), HERG and KCNE2, have been linked to heritable or acquired long-QT syndrome. Mechanisms whereby mutations of KCNE2 produce fatal cardiac arrhythmias characteristic of ...

The diversity of the voltage-gated K(+) (Kv) channel subfamily Kv2 is increased by interactions with auxiliary β-subunits and by assembly with members of the modulatory so-called silent Kv subfamilies (Kv5-Kv6 and Kv8-Kv9). However, it has not yet been investigated whether these two types of modulating subunits can associate within and modify a single channel complex simultaneously. Here, we de...

OBJECTIVES The function of Kv4.3 (KCND3) channels, which underlie the transient outward current I(to) in human heart, can be modulated by several accessory subunits such as KChIP2 and KCNE1-KCNE5. Here we aimed to determine the regional expression of Kv4.3, KChIP2, and KCNE mRNAs in non-failing and failing human hearts and to investigate the functional consequences of subunit coexpression in he...

Two different mechanisms leading to increased current have been described for the small-molecule human ether-à-go-go-related gene (herg) activator NS1643 [1,3-bis-(2-hydroxy-5-trifluoromethylphenyl)-urea]. On herg1a channels expressed in Xenopus laevis oocytes, it mainly acts via attenuation of inactivation and for rat (r) erg1b channels expressed in human embryonic kidney (HEK)-293 cells, it s...

Familial long QT syndrome (LQTS) is caused by mutations in genes encoding ion channels important in determining ventricular repolarization. Mutations in at least five genes have been associated with the LQTS. Fire genes, KCNQ1, HERG, SCN5A, KCNE1, and KCNE2, have been identified. We have identified a missense mutation in the HERG gene in identical twins in a Japanese family with LQTS. The ident...

Genomic microarray analysis of genes specifically expressed in a pure cell isolate from a heterocellular organ identified the likely K efflux channel associated with the gastric H-K-ATPase. The function of this channel is to supply K to the luminal surface of the pump to allow H for K exchange. KCNQ1-KCNE2 was the most highly expressed and significantly enriched member of the large variety of K...