Significance Lysosomes are the cell’s degradation center. To adapt to different environmental conditions, the cell has evolved a set of delicate mechanisms to rapidly change lysosome function, which is referred to as lysosomal adaptation. Notably, lysosomal adaptation is required for cell survival under low nutrient conditions. In this study, we identified TRPML1, a lysosomal Ca 2+ -permeant ion channel, as an essential player required for lysosomal adaptation. The activity of TRPML1 is potently (up to 10-fold) and rapidly increased upon nutrient starvation. Furthermore, pharmacological inhibition or genetic deletion of TRPML1 completely abolished the effects of starvation on boosting the degradation capability of lysosomes.

Up-regulation of lysosomal TRPML1 channels is essential for lysosomal adaptation to nutrient starvation