Negative regulator of the mTORC1 and mTORC2 complexes: inhibits the protein kinase activity of MTOR, thereby inactivating both complexes (PubMed:19446321, PubMed:22017875, PubMed:22017876, PubMed:22017877, PubMed:25936805, PubMed:29382726, PubMed:34519268, PubMed:34519269). DEPTOR inhibits mTORC1 and mTORC2 to induce autophagy (PubMed:22017875, PubMed:22017876, PubMed:22017877). In contrast to AKT1S1/PRAS40, only partially inhibits mTORC1 activity (PubMed:34519268, PubMed:34519269).