TRPA1 channel

Channel name TRPA11,2,3
Description Nonselective cation channel subunit
Other names ANKTM1 (ankyrin transmembrane protein 1)
Molecular information Human unigene: Hs0.137674, chr. 8q13
Mouse unigene: Mm0.186329, chr. 1 A3
Associated subunits Not established
Functional assays Patch-clamp, calcium imaging
Current Moderately outward rectifying >0 mV
Conductance Not established
Ion selectivity PNa/PCa ∼0.7
Activation Mustard oils, PLC-coupled GPCRs, icilin, cannabinoids, cold?, mechanosensation?
Inactivation Not established
Activators Icilin (100 μM)
Gating inhibitors None
Blockers Ruthenium red (5 μM)
Radioligands None
Channel distribution Expressed in sensory neurons of trigeminal and dorsal root ganglia; ear
Physiological functions Sensitive to plant-derived irritants such as mustard oils and perhaps to membrane/cytoskeletal perturbations such as stretch (as the hearing transduction channel); may depolarize nociceptors in response to pro-algesic agents (e.g. bradykinin, serotonin, and histamine) that activate PLC-coupled receptors; originally proposed to sense painfully cold temperatures
Mutations and pathophysiology Not established
Pharmacological significance Putative wasabi receptor
Comments Expressed by a subset of TRPV1-expressing sensory neurons
Decreased in fibroblasts after oncogenic transformation
  • chr., chromosome; GPCR, G protein-coupled receptor.

  • 1. Story GM, Peier AM, Reeve AJ, Eid SR, Mosbacher J, Hricik TR, Earley TJ, Hergarden AC, Andersson DA, Hwang SW, et al. (2003) ANKTM1, a TRP-like channel expressed in nociceptive neurons, is activated by cold temperatures. Cell 112:819-829

  • 2. Jordt SE, Bautista DM, Chuang HH, McKemy DD, Zygmunt PM, Hogestatt ED, Meng ID, and Julius D (2004) Mustard oils and cannabinoids excite sensory nerve fibres through the TRP channel ANKTM1. Nature (Lond) 427:260-265

  • 3. Corey DP, Garcia-Anoveros J, Holt JR, Kwan KY, Lin SY, Vollrath MA, Amalfitano A, Cheung EL, Derfler BH, Duggan A, et al. (2004) TRPA1 is a candidate for the mechanosensitive transduction channel of vertebrate hair cells. Nature (Lond) 432:723-730