KCNE2
Function
Ancillary protein that functions as a regulatory subunit of the voltage-gated potassium (Kv) channel complex composed of pore-forming and potassium-conducting alpha subunits and of regulatory beta subunits (PubMed:10219239, PubMed:11034315, PubMed:11101505, PubMed:12185453, PubMed:20533308). KCNE2 beta subunit modulates the gating kinetics and enhances stability of the channel complex (PubMed:10219239, PubMed:11034315, PubMed:11101505, PubMed:12185453, PubMed:20533308). Alters the gating of the delayed rectifier Kv channel containing KCNB1 alpha subunit (PubMed:11101505, PubMed:20533308). Associates with KCNH2/HERG alpha subunit Kv channel to form the rapidly activating component of the delayed rectifying potassium current (IKr) in heart (PubMed:10219239, PubMed:12185453). May associate with KCNQ2 and/or KCNQ3 alpha subunits to modulate the native M-type current (PubMed:11034315). May associate with HCN1 and HCN2 channel subunits to increase potassium current (By similarity). Forms a heterooligomer complex with KCNQ1/KVLQT1 alpha subunits which leads to currents with an apparently instantaneous activation, a rapid deactivation process and a linear current-voltage relationship and decreases the amplitude of the outward current (PubMed:11101505). KCNQ1-KCNE2 channel associates with Na(+)-coupled myo-inositol symporter in the apical membrane of choroid plexus epithelium and regulates the myo-inositol gradient between blood and cerebrospinal fluid with an impact on neuron excitability (By similarity).
Involvement in disease
Long QT syndrome 6
LQT6
A heart disorder characterized by a prolonged QT interval on the ECG and polymorphic ventricular arrhythmias. They cause syncope and sudden death in response to exercise or emotional stress, and can present with a sentinel event of sudden cardiac death in infancy.
None
The disease is caused by variants affecting the gene represented in this entry.
Atrial fibrillation, familial, 4
ATFB4
A familial form of atrial fibrillation, a common sustained cardiac rhythm disturbance. Atrial fibrillation is characterized by disorganized atrial electrical activity and ineffective atrial contraction promoting blood stasis in the atria and reduces ventricular filling. It can result in palpitations, syncope, thromboembolic stroke, and congestive heart failure.
None
The disease is caused by variants affecting the gene represented in this entry.
Sequence Similarities
Belongs to the potassium channel KCNE family.
Tissue Specificity
Highly expressed in brain, heart, skeletal muscle, pancreas, placenta, kidney, colon and thymus. A small but significant expression is found in liver, ovary, testis, prostate, small intestine and leukocytes. Very low expression, nearly undetectable, in lung and spleen.
Cellular localization
- Cell membrane
- Single-pass type I membrane protein
- Apical cell membrane
- Single-pass membrane protein
- Colocalizes with KCNB1 at the plasma membrane.
Alternative names
Potassium voltage-gated channel subfamily E member 2, MinK-related peptide 1, Minimum potassium ion channel-related peptide 1, Potassium channel subunit beta MiRP1, MiRP1, KCNE2