Transient outward potassium channel subunit Kv4.2 (Kv4.2)

Transient outward potassium channel subunit Kv4.2 is a pore-forming alpha-subunit belonging to the Shal-related family of voltage-gated potassium channels (Kv). It mediates fast-inactivating, A-type K+ currents that play a critical role in regulating membrane excitability both in neurons—where it shapes action potentials and synaptic integration—and in cardiomyocytes—where it contributes to early phase repolarization during the cardiac action potential. The protein forms tetrameric complexes with other related subunits and interacts with auxiliary proteins such as KChIPs that modulate its trafficking, surface expression, and biophysical properties. Its function can be dynamically regulated by phosphorylation through kinases including ERK/MAPK and PKA pathways, integrating multiple intracellular signals into changes in cellular excitability relevant for processes like learning/memory and heart rhythm control. Dysregulation has been implicated in pathologies such as arrhythmias due to electrical remodeling after heart injury/disease as well as disorders involving abnormal neuronal firing patterns.

Other names

Potassium voltage-gated channel subfamily D member 2KCND2Shal-related potassium channelA-type potassium channel Kv4.2Voltage-gated potassium channel subunit Kv4.2

For experimental modulators/blockers—blockade or modulation of the pore-forming alpha-subunit alters the amplitude, kinetics, or voltage-dependence of transient outward K+ currents.