Photoactivatable tandem fluorescence imaging of organelles and their interplay monitoring

Fluorescence imaging of organelles has significant advantages of high spatiotemporal resolution and easy operation, but most current fluorescent probes can only be used for targeted imaging of single organelles. Therefore, two or more fluorescent probes are usually required for monitoring the interplay between different organelles, which suffers from complicated operations. To tackle this challenge, we herein develop a photoactivatable fluorescent probe THTTVP for tandem imaging of organelles and in situ monitoring of their interplay with simple operation. Under light irradiation, one part of the THTTVP probe can selectively accumulate in lipid droplets (LDs) with turn-on green fluorescence, while the other parts can undergo a photo-oxidative dehydrogenation reaction to generate TTVP and accumulate in the cytomembrane and mitochondria with turn-on red fluorescence. The interplay between LDs and mitochondria under reactive oxygen species (ROS)-induced oxidative stress can be in situ and long-term monitored with a significant fluorescence spectral difference. We believe this photoactivatable tandem organelle imaging strategy is promising for the study of the organelle interplay in various physiological processes. Most fluorescent probes can only be used for targeted imaging of single organelles, we herein develop a photoactivatable probe for tandem imaging of different organelles and in situ monitoring of their interplay with simple operation.