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.[1] These channels are regulated by several mechanisms including
signaling lipids,
oxygen tension,
pH,
mechanical stretch, and
G-proteins.[2] 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.[3] The two-pore domain potassium channels instead are
dimers where each subunit is essentially two α-subunits joined together.[4]
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.[5] To quote Rang and Dale (2015), "The nomenclature is misleading, especially when they are incorrectly referred to as two-pore channels".[6]
^Doyle DA, Morais Cabral J, Pfuetzner RA, Kuo A, Gulbis JM, Cohen SL, et al. (April 1998). "The structure of the potassium channel: molecular basis of K+ conduction and selectivity". Science. 280 (5360): 69–77.
Bibcode:
1998Sci...280...69D.
doi:
10.1126/science.280.5360.69.
PMID9525859.
