TAS1R3 and infection: Akin to findings in the Tas1r3−/− mouse, the ETC hyperplasia observed after infection with Tritrichomnas ranier in wild-type mice was absent in Sucnr1−/− mice [56]: while clearly implicating succinate in the response, the source of the succinic acid/succinate was not defined and one possibility is that T. ranier evoked changes in the gut microbiome, increasing the bacterial production of succinate.