Two pore channel

Two-pore channels are a small family of cation-selective ion channels, with two known paralogs in the human genome. They contain two tandem K_V-style six-transmembrane domains fused on one polypeptide chain that form a dimers in the membrane. These channels are closely related to CatSper channels and, more distantly, to TRP channels.

TPC channels are found in both animal and plant cells. In mammalian cells, recent evidence has identified the two-pore channels (TPCs) within the endolysosomal system as NAADP-regulated Ca(2+) channels that release organellar Ca(2+) in response to NAADP. The TPCN genes are distinct from the KCNK genes encoding the Tandem pore domain potassium channels.