KCNE1

Potassium voltage-gated channel subfamily E member 1 is a is_associated_with::protein that in humans is encoded by the KCNE1 is_associated_with::gene.

KCNE1 is a gene that codes for the KCNE1 protein, which is one of five members of the KCNE family of proteins. It is also known as minK protein (minimal potassium subunits). It can both cause is_associated_with::Romano-Ward syndrome (is_associated_with::heterozygotes) and Jervell Lange-Nielsens syndrome (is_associated_with::homozygotes). Mutation D76N in the KCNE1 protein can lead to is_associated_with::long QT syndrome due to structural changes in the KvLQT1/KCNE1 complex, and people with these mutations are advised to avoid triggers of cardiac arrhythmia and prolonged is_associated_with::QT intervals, such as stress or strenuous exercise.

Function
KCNE1 associates with the pore region of is_associated_with::KvLQT1 (KCNQ1), and its transmembrane domain contributes to the selectivity filter of this heteromeric channel complex. The C-terminal domain of KCNE1, specifically from amino acids 73 to 79 is necessary for stimulation of slow delayed potassium rectifier current by SGK1. The interaction of KCNE1 with an is_associated_with::alpha helix in the S6 KvLQT1 domain contributes to the higher affinity this channel has for is_associated_with::benzodiazepine L7 and is_associated_with::chromanol 293B by repositioning amino acid residues to allow for this. KCNE1 destabilizes the S4-S5 alpha-helix linkage in the KvLQT1 channel protein in addition to destabilizing the S6 alpha helix, leading to slower activation of this channel when associated with KCNE1.

Interaction with KvLQT1
The alpha-helix of the KCNE1 protein interacts with the pore domain S5/S6 and with the S4 domain of the KCNQ1 (KvLQT1) channel. KCNE1 binds to this outer part of the KvLQT1 pore domain, and slides from this position into the “activation cleft” which leads to greater current amplitudes