Transient receptor potential channel, canonical 7 (IPR005463)
Short name: TRPC7_channel
Overlapping homologous superfamilies
- Transient receptor potential channel, canonical (IPR002153)
- Transient receptor potential channel, canonical 7 (IPR005463)
TRP (transient receptor potential) channels can be described as tetramers formed by subunits with six transmembrane domains and containing cation-selective pores, which in several cases show high calcium permeability. The molecular architecture of TRP channels is reminiscent of voltage-gated channels and comprises six putative transmembrane segments (S1-S6), intracellular N- and C-termini, and a pore-forming reentrant loop between S5 and S6 [PMID: 18535090].
TRP channels represent a superfamily conserved from worms to humans that comprise seven subfamilies [PMID: 20025796]: TRPC (canonical), TRPV (vanilloid), TRPM (melastatin or long TRPs), TRPA (ankyrin), whose only member is the transmembrane protein 1, TRPP(polycystin), TRPML (mucolipin) and TRPN (Nomp-C homologues), which has a single member that can be found in worms, flies, and zebrafish. TRPs are classified essentially according to their primary amino acid sequence rather than selectivity or ligand affinity, due to their heterogenous properties and complex regulation.
TRP channels are involved in many physiological functions, ranging from pure sensory functions, such as pheromone signalling, taste transduction, nociception, and temperature sensation, over homeostatic functions, such as Ca2+ and Mg2+ reabsorption and osmoregulation, to many other motile functions, such as muscle contraction and vaso-motor control [PMID: 20861159].
The classical or canonical TRPC family (formerly short-TRPs, STRPs) encompasses channels presenting a large number of different activation modes. Some are store-operated, whereas others are receptor-operated channels activated by the production of diacylglicerol or redox processes. TRPC proteins also control growth cone guidance in both mammalian and amphibian model systems. All seven channels of this family share the common property of activation through phospholipase C (PLC)-coupled receptors [PMID: 15909153]. It is believed that functional TRPC channels are generated in situ by association of four TRPC proteins to form either homotetramers or heterotetramers [PMID: 12032305].
On the basis of sequence similarity, TRPC channels can be subdivided into four subgroups group 1 (TRPC1), group 2 (TRPC2), group 3 (TRPC3, TRPC6 and TRPC7) and group 4 (TRPC4 and TRPC5) [PMID: 11864597]. While TRPC1 and TRPC2 are almost unique, TRPC4 and TRPC5 share approx. 65% identity. TRPC3, 6 and 7 form a structural and functional subfamily sharing 70-80% identity at the amino acid level and their common sensitivity towards diacylglycerol (DAG).
TRPC3, 6, and 7 interact physically and, upon coexpression, coassemble to form functional tetrameric channels [PMID: 15909153].