Thus, mTORC1 modulates cell growth and proliferation and the dysregulation of mTORC1 is closely related to many diseases such as cancer and diabetes, making mTORC1 an attractive therapeutic target.23 A recent study demonstrated that Ras-related GTPases (Rag) mediate amino acid-based activation of mTORC124 and that leucyl-tRNA synthetase (LRS) is thought to be a binding partner of Rag proteins, particularly RagD, in a leucine-dependent manner. Here, LARS1 is linked to cancer.