TRPC

TRPC is a family of transient receptor potential cation channels in animals.

TRPC channels form the subfamily of channels in humans most closely related to drosophila TRP channels. Structurally, members of this family possess a number of similar characteristics, including 3 or 4 ankyrin repeats near the N-terminus and a TRP box motif containing the invariant EWKFAR sequence at the proximal C-terminus. These channels are non-selectively permeable to cations, with a prevalence 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 1,4 and 5 and they are densely expressed in corticolimbic brain regions, like the hippocampus, prefrontal cortex and lateral septum.[2][3] These 3 channels are activated by the metabotropic glutamate receptor 1 agonist dihydroxyphenylglycine.[2]

In general, TRPC channels can be activated by phospholipase C stimulation, with some members also activated by diacylglycerol. There is at least one report that TRPC1 is also activated by stretching of the membrane and TRPC5 channels are activated by extracellular reduced thioredoxin.[4]

It has long been proposed that TRPC channels underlie the calcium release activated channels observed in many cell types.[5] These channels open due to the depletion of intracellular calcium stores. Two other proteins, stromal interaction molecules (STIMs) and Orais, however, have more recently been implicated in this process. STIM1 and TRPC1 can coassemble, complicating the understanding of this phenomenon.[1]

TRPC6 has been implicated in late onset Alzheimer's disease.[6]

  1. ^ a b Nilius B, Owsianik G, Voets T, Peters JA (2007). "Transient receptor potential cation channels in disease". Physiol. Rev. 87 (1): 165–217. doi:10.1152/physrev.00021.2006. PMID 17237345.
  2. ^ a b Fowler, MA; Sidiropoulou, K; Ozkan, ED; Phillips, CW; Cooper, DC (2007). "Corticolimbic Expression of TRPC4 and TRPC5 Channels in the Rodent Brain". PLOS ONE. 2 (6): e573. Bibcode:2007PLoSO...2..573F. doi:10.1371/journal.pone.0000573. PMC 1892805. PMID 17593972.
  3. ^ Fowler, M; Varnell, A; Dietrich, A.; Birnbaumer, L.; Cooper, DC. (2012). "Deletion of the trpc1 gene and the effects on locomotor and conditioned place-preference responses to cocaine". Nature Precedings. doi:10.1038/npre.2012.7153.1 (inactive 1 November 2024).{{cite journal}}: CS1 maint: DOI inactive as of November 2024 (link)
  4. ^ S. Z. Xu; P. Sukumar; F. Zeng; et al. (2008). "TRPC channel activation by extracellular thioredoxin". Nature. 451 (7174): 69–72. Bibcode:2008Natur.451...69X. doi:10.1038/nature06414. PMC 2645077. PMID 18172497.
  5. ^ Boulay G, Brown DM, Qin N, et al. (December 1999). "Modulation of Ca(2+) entry by polypeptides of the inositol 1,4, 5-trisphosphate receptor (IP3R) that bind transient receptor potential (TRP): evidence for roles of TRP and IP3R in store depletion-activated Ca(2+) entry". Proc. Natl. Acad. Sci. U.S.A. 96 (26): 14955–60. doi:10.1073/pnas.96.26.14955. PMC 24754. PMID 10611319.
  6. ^ Lessard CB; Lussier MP; Cayouette S; Bourque G; Boulay G. (2005). "The overexpression of presenilin2 and Alzheimer's-disease-linked presenilin2 variants influences TRPC6-enhanced Ca2+ entry into HEK293 cells". Cell Signal. 17 (4): 437–445. doi:10.1016/j.cellsig.2004.09.005. PMID 15601622.