However, mTOR is now the widely accepted name, since Tor was first discovered via genetic and molecular studies of sirolimus-resistant mutants of "Saccharomyces cerevisiae" that identified FKBP12, Tor1, and Tor2 as the targets of sirolimus and provided robust support that the FKBP12-sirolimus complex binds to and inhibits Tor1 and Tor2.