The TRP (transient receptor potential) family of proteins is a group of related ion channels which is becoming increasingly relevant to the field of nephrologists. The TRPs are cation channels which are responsible for moving Ca2+ and Mg2+ ions across membranes; they were originally found in Drosophila and are named based on the fact that when light is shined on the fruit fly eye, instead of having a sustained photoreceptor response, there is only a transient response.
Examples of TRPs which have become important in Nephrology include:
-PKD2 (the 2nd most common disease gene for ADPKD, which is being renamed “TRPP2” based on the newest classification scheme for the TRP channels).
-TRPV5 & TRPV6 are expressed in the apical membrane of distal convoluted tubule cells and are felt to be responsible for calcium reabsorption at this site.
-TRPM6 mutations have been associated with hereditary hypomagnesemia.
-TRPC6 mutations have been found to cause a subset of familial nephrotic syndrome.