P2X7

A ionotrophic ATP-gated cation channels receptor

General Information

Neurotransmitters are released from synaptic vesicles into the synaptic cleft where they can bind to neurotransmitter receptors located in the plasma membrane. Purines can act as neurotransmitters and the corresponding receptors can be subdivided into two families: P1 receptors are sensitive to adenosine while P2 receptors are triggered by ATP.
The P2 receptor family is composed of two major groups, the metabotrophic G protein coupled P2Y receptors and the ionotrophic ATP-gated cation channels receptors P2X. Seven P2X receptors have been identified so far which all share a similar transmembrane topology. They consist of N- and C-termini facing the cytoplasm, two transmembrane spanning domains and a large extracellular loop. Compared to P2X1-6 P2X7 has a much longer cytoplasmic C-terminal tail. The P2X1-7 receptors are able to form hetero- or homo-multimers. The tissue distribution and function of P2X7 is still under discussion.