Potassium channel subfamily K member 9 is a protein that in humans is encoded by the KCNK9gene.[4][5][6]
This gene encodes K2P9.1, one of the members of the superfamily of potassium channel proteins containing two pore-forming P domains. This open channel is highly expressed in the cerebellum. It is inhibited by extracellular acidification and arachidonic acid, and strongly inhibited by phorbol 12-myristate 13-acetate.[6][7] Phorbol 12-myristate 13-acetate is also known as 12-O-tetradecanoylphorbol-13-acetate (TPA). TASK channels are additionally inhibited by hormones and transmitters that signal through GqPCRs. The resulting cellular depolarization is thought to regulate processes such as motor control and aldosterone secretion. Despite early controversy about the exact mechanism underlying this inhibition, the current view is that Diacyl-glycerol, produced by the breakdown of Phosphatidylinositol-4,5-bis-phosphate by Phospholipase Cβ causes channel closure. [8]