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