MinK subdomains that mediate modulation of and association with KvLQT1.

ABSTRACT: KvLQT1 is a voltage-gated potassium channel expressed in cardiac cells that is critical for myocardial repolarization. When expressed alone in heterologous expression systems, KvLQT1 channels exhibit a rapidly activating potassium current that slowly deactivates. MinK, a 129 amino acid protein containing one transmembrane-spanning domain modulates KvLQT1, greatly slowing activation, increasing current amplitude, and removing inactivation. Using deletion and chimeric analysis, we have examined the structural determinants of MinK effects on gating modulation and subunit association. Coexpression of KvLQT1 with a MinK COOH-terminus deletion mutant (MinK DeltaCterm) in Xenopus oocytes resulted in a rapidly activated potassium current closely resembling currents recorded from oocytes expressing

SUBMITTER: Tapper AR 

PROVIDER: S-EPMC2233688 | biostudies-literature | 2000 Sep

REPOSITORIES: biostudies-literature