TRPM4 channel

Channel name TRPM41,2,3,4,5
Description Ca2+-activated Na+ channel
Other names FLJ20041, LTRPC4, TRPM4b
Molecular information Human unigene: Hs0.467101, chr. 19q13.33
Mouse unigene: Mm0.349430, chr. 7 B3
Associated subunits Not established
Functional assays Patch-clamp, calcium imaging
Current Steep outward rectification >0 mV; instantaneous I–V linear
Conductance 25pS (isotonic monovalent)
Ion selectivity PNa/PCa ∼100 (M4b)
Activation Kact: 300–500 nM [Ca2+]i; >1 μM
Inactivation Not established (Ca2+-regulated)
Activators [Ca2+]i
Gating inhibitors None
Blockers M4a: 80 μM La3+, Gd3+
M4b: intracellular free ATP4-, 1.7 μM, spermine, ADP
Radioligands None
Channel distribution Probably ubiquitous
Physiological functions Regulation of calcium oscillations in activated T lymphocytes
Myogenic cerebral artery constriction
Mutations and pathophysiology Not established
Pharmacological significance Not established
Comments VMCA is an unusual feature; decavanadate (2 μM) inhibits voltage dependence
  • chr., chromosome; VMCA, voltage-modulated calcium-activated.

  • 1. Launay P, Fleig A, Perraud AL, Scharenberg AM, Penner R, and Kinet JP (2002) TRPM4 is a Ca2+-activated nonselective cation channel mediating cell membrane depolarization. Cell 109:397-407

  • 2. Nilius B, Prenen J, Droogmans G, Voets T, Vennekens R, Freichel M, Wissenbach U, and Flockerzi V (2003) Voltage dependence of the Ca2+-activated cation channel TRPM4. J Biol Chem 278:30813-30820

  • 3. Earley S, Waldron BJ, and Brayden JE (2004) Critical role for transient receptor potential channel TRPM4 in myogenic constriction of cerebral arteries. Circ Res 95:922-929

  • 4. Launay P, Cheng H, Srivatsan S, Penner R, Fleig A, and Kinet JP (2004) TRPM4 regulates calcium oscillations after T cell activation. Science (Wash DC) 306:1374-1377

  • 5. Nilius B, Prenen J, Voets T, and Droogmans G (2004) Intracellular nucleotides and polyamines inhibit the Ca2+-activated cation channel TRPM4b. Pflugers Arch Eur J Physiol 448:70-75