| Primary Identifier | IPR028801 | Type | Family |
| Short Name | TPC1_animal |
| description | Two-pore segment channels (TPCs or TPCNs) are located in membranes of acidic intracellular organelles (such as endo-lysosomes and plant vacuoles) and contain two putative pore-forming repeats. Each of these repeats contains six transmembrane segments and an intervening pore-loop, an architecture featured in voltage-gated channels []. Functional TPC channels are assembled from two TPC protein subunits forming a pore that conducts mainly Ca2 and Na. TPCs exist as three isoforms (TPC1-3): TPC1 and TPC2 are the most universal isoforms since TPC3 is absent from the genomes of many animals including those of human, mice, rats and flies []. This entry represents TPC1 from animals [, ]. TPC1 was first identified as an NAADP (nicotinic acid adenine dinucleotide phosphate)-regulated Ca2+ channel. Later it was shown to serve as a voltage-gated highly-selective Na+ channel activated directly by PI(3,5)P2 (phosphatidylinositol 3,5-bisphosphate) that senses pH changes and confers electrical excitability to organelles [, , , , ]. |
