The first group, polycystic kidney disease 1 (PKD1)-like, containspolycystin-1 (Previously known as TRPP1), PKDREJ, PKD1L1, PKD1L2, and PKD1L3. Polycystin-1 contains numerous N-terminal adhesive domains that are important for cell-cell contact.[1] This group of subunits also contain a large extracellular domain with numerous polycystin motifs. These motifs are of unknown function and are located between the S6 and S7 segments. The large intracellular C-terminal segment of TRPP1 seems to interact with TRPP2 to act as a signaling complex.[2]
This group of TRPP members (previously known as TRPP2-like) are: TRPP1 (previously known as TRPP2 or PKD2), TRPP2 (previously known as TRPP3 or PKDL2), and TRPP3 (previously known as TRPP5 or polycystin-L2).[3] Unlike the previous group, which contain 11 membrane-spanning segments, this group resemble other TRP channels, having 6 membrane-spanning segments with intracellular N- and C-termini. All of the members of this group contain acoiled coil region in their C-terminus involved in the interaction with the polycystin-1 group. TRPP1 and TRPP3 form constitutively active cation-selective ion channels that are permeable to calcium. TRPP2 has also been implicated in sour taste perception. Coupling of PKD1 and TRPP1 recruits TRPP1 to the membrane. Here, its activity is decreased and it suppresses the activation ofG proteins by PKD1.[2]
"Transient Receptor Potential Channels".IUPHAR Database of Receptors and Ion Channels. International Union of Basic and Clinical Pharmacology. Archived fromthe original on 2021-10-25. Retrieved2008-12-17.
"TRIP Database".a manually curated database of protein-protein interactions for mammalian TRP channels.
