Potassium calcium-activated channel subfamily N member 4 (KCa3.1)

Potassium calcium-activated channel subfamily N member 4 (KCa3.1) is an intermediate-conductance, voltage-independent potassium ion channel expressed in human immune cells, vascular endothelium, and secretory organs, activated by intracellular calcium via constitutive calmodulin binding[2][3][5]. KCa3.1 is crucial for maintaining the negative membrane potential that enables calcium influx during immune cell activation, especially in T lymphocytes[1][3][4][5]. Its pharmacological blockade has shown efficacy in preclinical models of inflammatory, autoimmune, and vascular diseases, and it is upregulated in certain cancers, making it a promising therapeutic target for immunomodulation, cancer, and vascular disorders[3][4][5]. The channel is best known for its involvement in diseases such as inflammatory bowel disease, rheumatoid arthritis, multiple sclerosis, and sickle cell disease, and it is frequently referred to as the Gardos channel in erythrocytes[1][2][3][5].

Other names

KCNN4IK1SK4HKCa4HSK4HIKCa1Intermediate conductance calcium-activated potassium channel protein 4Small conductance calcium-activated potassium channel 4Potassium channel, calcium activated intermediate/small conductance subfamily N alpha, member 4Potassium intermediate/small conductance calcium-activated channel, subfamily N, member 4Gardos channel

Channel blockers: Inhibit potassium efflux, reducing immune cell activation, proliferation, or migration. Channel activators: Enhance potassium flux, modulate endothelial/vascular function.