Potassium voltage-gated channel subfamily H member 3 (KCNH3)

Potassium voltage-gated channel subfamily H member 3 (KCNH3) is a tetrameric transmembrane ion channel from the Kv12.x family (Kv12.2) classified as a voltage-gated potassium channel[2][3]. It is predominantly expressed in the brain and modulates neuronal excitability by permitting selective potassium ion (K⁺) conductance in response to changes in membrane potential, which stabilizes or resets the neuronal membrane after depolarization[2][3]. Structurally, each subunit comprises six transmembrane segments (S1–S6), with the S4 helix serving as the voltage sensor[2]. Upon depolarization, conformational changes shift the channel into its open configuration, allowing K⁺ efflux to repolarize the cell membrane; the channel undergoes rapid gating and inactivation cycles that are critical for precise neuronal signaling[1][2]. Dysfunction or genetic variation in KCNH3 has been implicated in memory deficits, cognitive performance alterations, and increased seizure susceptibility[3]. No drugs are directly targeted to KCNH3 in clinical practice; however, it represents a promising therapeutic target for CNS conditions by virtue of its role in neural circuit modulation[3].

Other names

Voltage-gated inwardly rectifying potassium channel KCNH3KIAA1282BEC1ELK channel 2ELK2Kv12.2Brain-specific eag-like channel 1Ether-a-go-go-like potassium channel 2voltage-gated potassium channel subunit Kv12.2ether-a-go-go K(+) channel family member

Modulation of potassium ion flux, control of cellular membrane potential, action potential regulation, channel opening/inactivation[1][2]