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 . Their name is derived from the fact that the α subunits consist of four transmembrane segments, each containing two pore loops. As such, they structurally correspond to two inward-rectifier α subunits and thus form dimers in the membrane.
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".
^ abGoldstein SA, Bayliss DA, Kim D, Lesage F, Plant LD, Rajan S (Dec 2005). "International Union of Pharmacology. LV. Nomenclature and molecular relationships of two-P potassium channels". Pharmacological Reviews. 57 (4): 527–40. doi:10.1124/pr.57.4.12. PMID16382106.
^Gutman GA, Chandy KG, Adelman JP, Aiyar J, Bayliss DA, Clapham DE, et al. (Dec 2003). "International Union of Pharmacology. XLI. Compendium of voltage-gated ion channels: potassium channels". Pharmacological Reviews. 55 (4): 583–6. doi:10.1124/pr.55.4.9. PMID14657415.
^Goldstein SA, Bockenhauer D, O'Kelly I, Zilberberg N (Mar 2001). "Potassium leak channels and the KCNK family of two-P-domain subunits". Nature Reviews. Neuroscience. 2 (3): 175–84. doi:10.1038/35058574. PMID11256078.
^Sano Y, Inamura K, Miyake A, Mochizuki S, Kitada C, Yokoi H, Nozawa K, Okada H, Matsushime H, Furuichi K (Jul 2003). "A novel two-pore domain K+ channel, TRESK, is localized in the spinal cord". The Journal of Biological Chemistry. 278 (30): 27406–12. doi:10.1074/jbc.M206810200. PMID12754259.
^Czirják G, Tóth ZE, Enyedi P (Apr 2004). "The two-pore domain K+ channel, TRESK, is activated by the cytoplasmic calcium signal through calcineurin". The Journal of Biological Chemistry. 279 (18): 18550–8. doi:10.1074/jbc.M312229200. PMID14981085.