Voltage-gated potassium channel subunit Kv1.5 (Kv1.5 channel)

Voltage-gated potassium channel subunit Kv1.5 is a membrane protein responsible for conducting the ultra-rapid delayed rectifier K(+) current (I~Kur~), critical for atrial repolarization in the human heart. Structurally, each channel is formed by four pore-forming α-subunits comprising six transmembrane segments (S1–S6); the selectivity filter within the pore region enables potassium ion selectivity. Kv1.5 channels are selectively expressed in atrial rather than ventricular myocytes, making them an attractive target for atrial-selective antiarrhythmic agents to treat atrial fibrillation without triggering ventricular proarrhythmia. Genetic mutations in the KCNA5 gene are linked to familial atrial fibrillation, and alterations in Kv1.5 channel function are implicated in various cardiovascular and oncological pathologies. Drug development faces challenges due to selectivity and variable expression, with both small molecules (e.g., vernakalant) and peptides explored as therapeutic modulators.

Other names

Kv1.5KCNA5Shaker-related voltage-gated potassium channelI~Kur~ channel

Open-channel block (many inhibitors act by blocking the channel when open); Selective inhibition of I~Kur~ current; Peptide toxin binding (increased selectivity and affinity compared to small molecules)