Imaging of Mitophagy Enabled by an Acidity-Reporting Probe Anchored on the Mitochondrial Inner Membrane.

Classical chemical probes are prone to dissipation from stressed organelles, as evidenced by the incapability of mitochondrial dyes to image mitophagy linked to multiple diseases. We herein reported mitophagy imaging via ovalent nchoring of a ysosomal probe to the itochondrial inner membrane (). Utilizing , an azide-conjugatable probe with acidity-triggered fluorescence, is operated via ΔΨm-promoted probe accumulation in mitochondria and thereby bioorthogonal ligation of the trapped probe with azido-choline (choline) metabolically installed on the mitochondrial membrane. Overcoming the limitation of synthetic probes to dissipate from stressed organelles, enables signal-on fluorescence imaging of mitophagy induced by starvation and is further employed to reveal mitophagy in ferroptosis. These results suggest the potential of as a new tool to study mitophagy.