TPC1 / TPC2 | Two Pore Segment Channel 1 and 2
Family:
Two Pore Segment Channels
Subgroups:
2 members: TPC1, TPC2
Topology:
The channel protein contains two repeats (domains I and II). Each of the two repeats contains five hydrophobic transmembrane segments (S1, S2, S3, S5, S6) and one positively charged transmembrane segment (S4). TPCs are formed by two transmembrane non-equivalent tandem Shaker-like pore-forming subunits, dimerized to form quasi-tetramers.
Regulation and function:
Activation of TPCs is induced by a decrease in transmembrane potential, or by an increase in calcium concentrations in the cytosol. Low pH of the lumen and low calcium concentration could cause inhibition of these channels. Expression of TPCs are found in both plant vacuoles and animal acidic organelles (endosomes and lysosomes). TPCs regulate sodium and calcium ion conductance, intravesicular pH, and trafficking excitability.
Publications
2014 - High susceptibility to fatty liver disease in two-pore channel 2-deficient mice
Port-a-Patch publication in Nature Communications (2014)
Authors:
Grimm C., Holdt L.M., Chen C.C., Hassan S., Müller C., Jörs S., Cuny H., Kissing S., Schröder B., Butz B., Northoff B., Castonguay J., Luber C.A., Moser M., Spahn S., Lüllmann-Rauch R., Fendel C., Klugbauer N., Griesbeck O., Haas A., Mann M., Bracher F., Teupser D., Saftig P., Biel M., Wahl-Schott C.
2010 - Planar Patch Clamp Approach to Characterize Ionic Currents from Intact Lysosomes
Port-a-Patch publication in Science Signaling (2010)
Authors:
Schieder M., Rötzer K., Brüggemann A., Biel M., Wahl-Schott C.
2010 - Characterization of two pore channel 2 (TPCN2) -mediated Ca2+ currents in isolated lysosomes
Port-a-Patch publication in The Journal of Biological Chemistry (2010)
Authors:
Schieder M., Rötzer K., Brüggemann A., Biel M., Wahl-Schott C.A.