Potassium channels are the most widely distributed type of ion channel found in virtually all organisms. They form potassium-selective pores that span cell membranes. Potassium channels are found in most cell types and control a wide variety of cell functions.
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, and each pair of transmembrane segments contains a pore loop between the two transmembrane segments. Thus, each subunit has two pore loops. As such, they structurally correspond to two inward-rectifier α subunits and thus form dimers in the membrane.
Potassium channel subfamily K member 2, also known as TREK-1, is a protein that in humans is encoded by the KCNK2 gene.
Potassium voltage-gated channel subfamily KQT member 4, also known as voltage-gated potassium channel subunit Kv7.4, is a protein that in humans is encoded by the KCNQ4 gene.
Potassium channel subfamily K member 1 is a protein that in humans is encoded by the KCNK1 gene.
Potassium channel subfamily K member 9 is a protein that in humans is encoded by the KCNK9 gene.
Potassium channel subfamily K member 4 is a protein that in humans is encoded by the KCNK4 gene. KCNK4 protein channels are also called TRAAK channels.
Potassium channel subfamily K member 6 is a protein that in humans is encoded by the KCNK6 gene.
Potassium channel subfamily K member 5 is a protein that in humans is encoded by the KCNK5 gene.
Potassium channel subfamily K member 15 is a protein that in humans is encoded by the KCNK15 gene.
Potassium channel subfamily K member 17 is a protein that in humans is encoded by the KCNK17 gene.
Potassium channel, subfamily K, member 7, also known as KCNK7 or K2P7.1 is a protein which is encoded in humans by the KCNK7 gene. K2P7.1 is a potassium channel containing two pore-forming P domains. Multiple transcript variants encoding different isoforms have been found for this gene.
Potassium channel, subfamily K, member 10, also known as KCNK10 is a human gene. The protein encoded by this gene, K2P10.1, is a potassium channel containing two pore-forming P domains.
Potassium channel, subfamily K, member 12, also known as KCNK12 is a human gene. The protein encoded by this gene, K2P12.1, is a potassium channel containing two pore-forming P domains.
Potassium channel, subfamily K, member 13, also known as KCNK13 is a human gene. The protein encoded by this gene, K2P13.1 is a potassium channel containing two pore-forming P domains.
Potassium channel subfamily K member 16 is a protein that in humans is encoded by the KCNK16 gene. The protein encoded by this gene, K2P16.1, is a potassium channel containing two pore-forming P domains.
Potassium channel subfamily K member 18 (KCNK18), also known as TWIK-related spinal cord potassium channel (TRESK) or K2P18.1 is a protein that in humans is encoded by the KCNK18 gene. K2P18.1 is a potassium channel containing two pore-forming P domains.
Potassium channel blockers are agents which interfere with conduction through potassium channels.
A potassium channel opener is a type of drug which facilitates ion transmission through potassium channels.
Mechanosensitive channels, mechanosensitive ion channels or stretch-gated ion channels (not to be confused with mechanoreceptors). They are present in the membranes of organisms from the three domains of life: bacteria, archaea, and eukarya. They are the sensors for a number of systems including the senses of touch, hearing and balance, as well as participating in cardiovascular regulation and osmotic homeostasis (e.g. thirst). The channels vary in selectivity for the permeating ions from nonselective between anions and cations in bacteria, to cation selective allowing passage Ca2+, K+ and Na+ in eukaryotes, and highly selective K+ channels in bacteria and eukaryotes.
