Distinct subdomains of the KCNQ1 S6 segment determine channel modulation by different KCNE subunits.

ABSTRACT: Modulation of voltage-gated potassium (KV) channels by the KCNE family of single transmembrane proteins has physiological and pathophysiological importance. All five KCNE proteins (KCNE1-KCNE5) have been demonstrated to modulate heterologously expressed KCNQ1 (KV7.1) with diverse effects, making this channel a valuable experimental platform for elucidating structure-function relationships and mechanistic differences among members of this intriguing group of accessory subunits. Here, we specifically investigated the determinants of KCNQ1 inhibition by KCNE4, the least well-studied KCNE protein. In CHO-K1 cells, KCNQ1, but not KCNQ4, is strongly inhibited by coexpression with KCNE4. By studying KCNQ1-KCNQ4 chimeras, we identified two adjacent residues (K326 and T327) within the extracellular

SUBMITTER: Vanoye CG 

PROVIDER: S-EPMC2737226 | biostudies-literature | 2009 Sep

REPOSITORIES: biostudies-literature