SEC13 is a multifunctional protein with roles in nutrient sensing and protein trafficking. As a component of the GATOR2 complex, SEC13 functions as a nutrient-sensing hub that activates mTORC1 signaling in response to amino acids 1. Within GATOR2, SEC13 and SEH1L stabilize the five-subunit complex through β-propeller blade donation, enabling its cage-like architecture to interact with amino acid sensors SESN2 and CASTOR1 1. GATOR2 indirectly activates mTORC1 by inhibiting GATOR1 through ubiquitin-mediated degradation of NPRL2, an amino acid-dependent mechanism that suppresses mTORC1 activity during nutrient starvation 2. Beyond nutrient sensing, SEC13 functions in endoplasmic reticulum-to-Golgi protein trafficking as a COPII component 3. In oligodendrocytes, SEC13-dependent trafficking is essential for myelin formation and repair, operating through autocrine pleiotrophin signaling 3. SEC13 additionally localizes to the nuclear pore complex, where it stably interacts with Nup96 and shuttles between nuclear and cytoplasmic compartments 4. Clinically, SEC13 dysregulation has emerged in acute lung injury, where elevated SEC13 promotes glycolysis and epithelial-mesenchymal transition through Pgm1 stabilization 5. SEC13's dual involvement in mTORC1 signaling and protein trafficking positions it as a critical metabolic and cellular transport regulator with implications for cancer, neurological disease, and inflammatory pathology.