We and others have uncovered numerous functions for mTOR, particularly regarding its role in cell growth control. However, despite these advances, numerous questions remain. For instance, 1) how does the small GTPase protein Rheb activate mTORC1? 2) how do amino acids activate mTORC1. 3) how does mTORC1 regulate autophagy in mammals? 4) what other components reside in TORC1 and TORC2? 5) how does PI3K regulate mTORC2? 6) what are the physiological roles of mTORC1 and mTORC2? 7) Does dysregulation of mTOR signaling cause human diseases other than cancer.