Potassium Channel Subfamily K, Member 4 (KCNK4)

K2P4.1 homodimerizes and functions as an outwardly rectifying channel. It is expressed primarily in neural tissues and is stimulated by membrane stretch and polyunsaturated fatty acids.Mouse Kcnk4 is not expressed in placenta but, like the human transcript, is highly expressed only in neuronal tissues. Electrophysiologic studies in COS cells expressing KCNK4 indicated that human KCNK4 shares the same biophysical and pharmacologic properties as mouse TRAAK. KCNK4 currents are K+ selective, instantaneous, noninactivating, and outwardly rectifying. They are not sensitive to classic K+ channel blockers such as quinidine, TEA, and barium, but are potentiated by polyunsaturated fatty acids such as arachidonic acid.