KCNE4 Protein is a potassium channel regulatory subunit encoded by the [KCNE4](/genes/kcne4) gene (also known as MiRP3). It belongs to the KCNE family of single transmembrane domain proteins that modulate the function of voltage-gated potassium channels. The UniProt ID is [Q8WXX4](https://www.uniprot.org/uniprot/Q8WXX4) [1].
Introduction
KCNE4 is a critical modulator of neuronal and cardiac potassium channel function. As part of the KCNE family (KCNE1-5), KCNE4 assembles with various potassium channel α-subunits to form functionally distinct channels with unique biophysical properties, localization patterns, and regulatory mechanisms [2]. While most extensively studied in cardiac tissue, emerging research suggests important roles for KCNE4 in neuronal excitability, neurotransmitter release, and potentially in neurodegenerative disease processes. [@rouraferrer2010]
KCNE4 Protein is a potassium channel regulatory subunit encoded by the [KCNE4](/genes/kcne4) gene (also known as MiRP3). It belongs to the KCNE family of single transmembrane domain proteins that modulate the function of voltage-gated potassium channels. The UniProt ID is [Q8WXX4](https://www.uniprot.org/uniprot/Q8WXX4) [1].
Introduction
KCNE4 is a critical modulator of neuronal and cardiac potassium channel function. As part of the KCNE family (KCNE1-5), KCNE4 assembles with various potassium channel α-subunits to form functionally distinct channels with unique biophysical properties, localization patterns, and regulatory mechanisms [2]. While most extensively studied in cardiac tissue, emerging research suggests important roles for KCNE4 in neuronal excitability, neurotransmitter release, and potentially in neurodegenerative disease processes. [@rouraferrer2010]
Structure
Molecular Architecture
KCNE4 is a small single-pass transmembrane protein with the following structural features: [@mccrossan2004]
Molecular Weight: Approximately 16-18 kDa
Transmembrane Domain: Single α-helical transmembrane segment spanning residues 73-95
N-terminal Cytoplasmic Domain: Proline-rich region that influences channel trafficking
C-terminal Cytoplasmic Domain: Contains multiple regulatory sites for post-translational modification
KCNQ1 (Kv7.1) Channels: KCNE4 co-assembles with KCNQ1 to form slowly activating delayed rectifier potassium currents (I_Ks). Unlike KCNE1 which prolongs channel opening, KCNE4 accelerates activation and shifts the voltage dependence to more positive potentials [3].
Unknown, UniProt Q8WXX4 - KCNE4 human protein (n.d.)
[Roura-Ferrer M, et al., Functional implications of KCNE4 expression and assembly in neuronal cells. J Neurochem. 2010;115(2):332-342 (2010)](https://pubmed.ncbi.nlm.nih.gov/20633205/)