The Lysosome: A Signaling Hub

Far beyond its role in degradation, the lysosome functions as a critical sensing platform. Its membrane is the physical interface where multiple signaling inputs converge. At the heart of lysosomal signaling pathways is the mTORC1 (mechanistic target of rapamycin complex 1), which serves as the master regulator of cellular growth and metabolism. Our research explores how the lysosomal membrane acts as a sophisticated command center where nutrient availability and growth factor signals are integrated to control mTORC1 activity. We are specifically focused on the upstream "logic" that governs mTORC1 activation. A primary interest is understanding how growth factor signals ultimately converge with nutrient signals at the lysosomal membrane. To decode these processes, we utilize in vitro reconstitution, biochemical and biophysical characterization, and high-resolution cryo-electron microscopy (cryo-EM) to delineate these complexes in states that mimic their native membrane environment.