The two-pore-domain or tandem pore domain potassium channels are a family of 15 members that form what is known as leak channels which possess Goldman-Hodgkin-Katz (open) rectification. These channels are regulated by several mechanisms including signaling lipids, oxygen tension, pH, mechanical stretch, and G-proteins. Two-pore-domain potassium channels correspond structurally to a inward-rectifier potassium channel α-subunits. Each inward-rectifier potassium channel α-subunit is composed of two transmembrane α-helices, a pore helix and a potassium ion selectivity filter sequence and assembles into a tetramer forming the complete channel. The two-pore domain potassium channels instead are dimers where each subunit is essentially two α-subunits joined together.

Each single channel does not have two pores; the name of the channel comes from the fact that each subunit has two P (pore) domains in its primary sequence. To quote Rang and Dale (2015), "The nomenclature is misleading, especially when they are incorrectly referred to as two-pore channels".

A decrease in these leak channels activity is known as 'channel arrest', which reduces oxygen consumption and allows animals to survive anoxia.

Below is a list of the 15 known two-pore-domain human potassium channels:

Gene Channel Family Aliases K2p1.1 TWIK TWIK-1 K2p2.1 TREK TREK-1 K2p3.1 TASK TASK-1 K2p4.1 TREK TRAAK K2p5.1 TASK TASK-2 K2p6.1 TWIK TWIK-2 K2p7.1 TWIK K2p9.1 TASK TASK-3 K2p10.1 TREK TREK-2 K2p12.1 THIK THIK-2 K2p13.1 THIK THIK-1 K2p15.1 TASK TASK-5 K2p16.1 TALK TALK-1 K2p17.1 TALK TALK-2, TASK-4 K2p18.1 TRIK, TRESK

See also Ion channel Potassium channel

References

External links