Real-Time Monitoring of Adenosine Triphosphate Fluctuation in Lysosome during Autophagy/Mitophagy.

Autophagy, a lysosomal degradation pathway critical for cell survival, differentiation, development, and maintaining homeostasis, plays a crucial role in cellular health. Maintaining an adequate level of adenosine triphosphate (ATP), the central molecule in energy metabolism, is equally essential for these processes. However, the interplay between autophagy and energy metabolism remains incompletely understood due to technical challenges, including the need for high-precision, dynamic detection within organelles, and sensitivity to the acidic lysosomal environment. To address these limitations, we developed HR-MP, a ratiometric fluorogenic nanoprobe specifically designed for visualizing ATP levels in acidic lysosomes during autophagy. HR-MP exhibits selective, rapid, and quantitative ATP detection in vitro, allowing it to quantitatively monitor lysosomal ATP fluctuations in complex biological environments with excellent biocompatibility, membrane permeability, and lysosome-targeting ability. Importantly, HR-MP enables real-time tracking of ATP fluctuations during starvation- or drug-induced autophagy in living cells, providing a powerful tool for elucidating the links between autophagy and energy metabolism.