TRPM5 channel

Channel name TRPM51,2,3
Description Nonselective, monovalent cation channel
Other names Mtr1, LTRPC5
Molecular information Human unigene: Hs0.272287, chr. 11p15.5
Mouse unigene: Mm0.286668, chr. 7 F5
Associated subunits Not established
Functional assays Patch-clamp, calcium imaging
Current Steep outward rectification >0 mV
Conductance 23pS (isotonic monovalent)
Ion selectivity PNa/PCa = >20 (monovalent selective)
Activation GPCR (T1R, T2R), Ggus-PLCβ2 [Ca2+]i 1—100 μM
Inactivation Not established
Activators [Ca2+]i
Gating inhibitors None
Blockers Not established
Radioligands None
Channel distribution Widely distributed, eye, liver, lung, tongue, stomach
Physiological functions Sweet, bitter, umami taste transduction
Mutations and pathophysiology Not established
Pharmacological significance Not established
Comments VMCA is an unusual feature; candidate gene for rhabdomyosarcomas, Wilms' tumor, and Beckwith-Wiedemann syndrome
  • chr., chromosome; GPCR, G protein-coupled receptor; VMCA, voltage-modulated calcium-activated.

  • 1. Hofmann T, Chubanov V, Gudermann T, and Montell C (2003) TRPM5 is a voltage-modulated and Ca2+-activated monovalent selective cation channel. Curr Biol 13:1153-1158

  • 2. Liu D and Liman ER (2003) Intracellular Ca2+ and the phospholipid PIP2 regulate the taste transduction ion channel TRPM5. Proc Natl Acad Sci USA 100:15160-15165

  • 3. Prawitt D, Monteilh-Zoller MK, Brixel L, Spangenberg C, Zabel B, Fleig A, and Penner R (2003) TRPM5 is a transient Ca2+-activated cation channel responding to rapid changes in [Ca2+]i. Proc Natl Acad Sci USA 100:15166-15171