This domain is found in a group of Trp proteins from animals, generally located C-terminal to ankyrin repeats ( IPR002110 ). There is strong evidence that Trp proteins are structural elements of calcium-ion entry channels activated by G protein-coupled receptors [ PUBMED:10051594 … expand

This domain is found in a group of Trp proteins from animals, generally located C-terminal to ankyrin repeats ( IPR002110 ). There is strong evidence that Trp proteins are structural elements of calcium-ion entry channels activated by G protein-coupled receptors [ PUBMED:10051594 ].

Transient receptor potential (TRP) 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 [ PUBMED:18535090 ].

TRP channels represent a superfamily conserved from worms to humans that comprise seven subfamilies [ PUBMED:20025796 ]: TRPC (canonical), TRPV (vanilloid), TRPM (melastatin or long TRPs), TRPA (ankyrin, whose only member is Transient receptor potential cation channel subfamily A member 1, TrpA1), 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 heterogeneous 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 [ PUBMED:20861159 ].