TRPC3 channel

Channel name TRPC31,2,3,4,5,6
Description Diacylglycerol-Ca2+-activated TRP channel
Other names mTRPC3
Molecular information Human unigene: Hs0.150981, chr. 4q27
Mouse unigene: Mm0.74363, chr. 3
Associated subunits TRPC6, TRPC7, FKBP12, VAMP2, syntaxin, SNAP, NCX1, TrkB
Functional assays Patch-clamp, calcium imaging
Current Inwardly and outwardly rectifying, nonselective cation current
Conductance 66pS2
Ion selectivity PNa/PCa = 1:1.5
Activation Intracellular Ca2+
Inactivation Not established
Activators Activated either by DAG or direct interaction with the IP3 receptor in vitro; activated through a BDNF, TrkB-mediated pathway in neurons
Gating inhibitors None
Blockers 2-APB, 1–25 μM Gd3+, La3+, RuR
Radioligands None
Channel distribution Brain, placenta, heart, muscle, smooth muscle
Physiological functions Resistance artery myogenic tone, airway regulation
Mutations and pathophysiology Not established
Pharmacological significance Not established
Comments DAG response is PKC-independent
  • chr., chromosome; TrkB, tyrosine kinase B; BDNF, brain-derived neurotrophic factor; RuR, ruthenium red.

  • 1. Hofmann T, Schaefer M, Schultz G, and Gudermann T (2002) Subunit composition of mammalian transient receptor potential channels in living cells. Proc Natl Acad Sci USA 99:7461-7466

  • 2. Hofmann T, Obukhov AG, Schaefer M, Harteneck C, Gudermann T, and Schultz G (1999) Direct activation of human TRPC6 and TRPC3 channels by diacylglycerol. Nature (Lond) 397:259-263

  • 3. Sinkins WG, Goel M, Estacion M, and Schilling WP (2004) Association of immunophilins with mammalian TRPC channels. J Biol Chem 279:34521-34529

  • 4. Treves S, Franzini-Armstrong C, Moccagatta L, Arnoult C, Grasso C, Schrum A, Ducreux S, Zhu MX, Mikoshiba K, et al. (2004) Junctate is a key element in calcium entry induced by activation of InsP3receptors and/or calcium store depletion. J Cell Biol 166:537-548

  • 5. Singh BB, Lockwich TP, Bandyopadhyay BC, Liu X, Bollimuntha S, Brazer SC, Combs C, Das S, Leenders AG, Sheng ZH, et al. (2004) VAMP2-dependent exocytosis regulates plasma membrane insertion of TRPC3 channels and contributes to agonist-stimulated Ca2+ influx. Mol Cell 15:635-646

  • 6. Rosker C, Graziani A, Lukas M, Eder P, Zhu MX, Romanin C, and Groschner, K (2004) Ca2+ signaling by TRPC3 involves Na+ entry and local coupling to the Na+/Ca2+ exchanger. J Biol Chem 279:13696-13704