Test 3

TRPC channels form the subfamily of channels in human most closely related to drosophila TRP channels. In terms of structure, this family possesses a number of similar characteristics. At the proximal C-terminus of this sub-family is a TRP box motif containing the invariant EWKFAR sequence and between 3 and 4 ankyrin repeats near the N-terminus. These channels are non-selectively permeable to cations, with a selectivity of calcium over sodium variable among the different members. Many of TRPC channel subunits are able to coassemble.[1] The predominant TRPC channels in the mammalian brain are the TRPC 4,5 and 1. These TRPC channels are activated the metabotropic glutamate receptor 5 using DHPG.[2] In general, TRPC channels can be activated by phospholipase C stimulation, with some members also activated by diacylglycerol. There is one at least one report that TRPC1 is also activated by stretching of the membrane and TRPC5 channels are activated by extracellular reduced thioredoxin. [3]