The
two-pore-domain potassium channel (not to be confused with the small family of
two-pore channels) a family of 15 members form what is known as "leak channels" which possess
Goldman-Hodgkin-Katz (open)
rectification. These channels are regulated by several mechanisms including
oxygen tension,
pH, mechanical stretch, and
G-proteins . Their name is derived from the fact that the a subunits consist of four
transmembrane segments, each containing two pore loops. As such, they structurally correspond to two inward-rectifier a subunits and thus form
dimers in the membrane.