KCNE2 confers background current characteristics to the cardiac KCNQ1 potassium channel

Citation
N. Tinel et al., KCNE2 confers background current characteristics to the cardiac KCNQ1 potassium channel, EMBO J, 19(23), 2000, pp. 6326-6330
Citations number
28
Categorie Soggetti
Molecular Biology & Genetics
Journal title
EMBO JOURNAL
ISSN journal
02614189 → ACNP
Volume
19
Issue
23
Year of publication
2000
Pages
6326 - 6330
Database
ISI
SICI code
0261-4189(200012)19:23<6326:KCBCCT>2.0.ZU;2-V
Abstract
Mutations in HERG and KCNQ1 (or KVLQT1) genes cause the life-threatening Lo ng QT syndrome. These genes encode K+ channel pore-forming subunits that as sociate with ancillary subunits from the KCNE family to underlie the two co mponents, I-Kr and I-Ks, of the human cardiac delayed rectifier current I-K . The KCNE family comprises at least three members. KCNE1 (IsK or MinK) rec apitulates I-Ks, when associated with KCNQ1, whereas it augments the amplit ude of an I-Kr-like current when co-expressed with HERG, KCNE3 markedly cha nges KCNQ1 as well as HERG current properties. So far, KCNE2 (MirP1) has on ly been shown to modulate HERG current, Here we demonstrate the interaction of KCNE2 with the KCNQ1 subunit, which results in a drastic change of KCNQ 1 current amplitude and gating properties. Furthermore, KCNE2 mutations als o reveal their specific functional consequences on KCNQ1 currents. KCNQ1 an d HERG appear to share unique interactions with KCNE1, 2 and 3 subunits, Wi th the exception of KCNE3, mutations in all these partner subunits have bee n found to lead to an increased propensity for cardiac arrhythmias.