 mammalian target of rapamycin ( mtor ) signalling and macroautophagy ( henceforth autophagy ) regulate numerous pathological and physiological processes including cellular responses to altered nutrient levels . however , the mechanisms regulating mtor and autophagy remain incompletely understood . 
 lysosomes are dynamic intracellular organelles 1 , 2 intimately involved both in the activation of mtor complex 1 ( mtorc1 ) signalling and in degrading autophagic substrates 3 - 8 . here 
 we report that lysosomal positioning coordinates anabolic and catabolic responses to changes in nutrient availability by orchestrating early plasma membrane signalling events , mtorc1 signalling and autophagy . 
 activation of mtorc1 by nutrients correlates with its presence on peripheral lysosomes that are physically close to the upstream signalling modules , while starvation causes perinuclear clustering of lysosomes , driven by changes in intracellular ph ( phi ) . 
 lysosomal positioning regulates mtorc1 signalling , which , in turn , influences autophagosome formation . 
 lysosome positioning also influences autophagosome - lysosome fusion rates , and thus controls autophagic flux by acting both at the initiation and termination stages of the process . 
 our findings provide a fundamental physiological role for the dynamic state of lysosomal positioning in cells as a coordinator of mtorc1 signalling with autophagic flux . 
Supplementary Material