Related Experiment Video
Updated: Jun 9, 2026
Visualizing Mitophagy with Fluorescent Dyes for Mitochondria and Lysosome
Published on: November 30, 2022
A Mitochondria-Targeting and Peroxynitrite-Activatable Ratiometric Fluorescent Probe for Precise Tracking of
Xianzhi Chai1,2, Xiuhua Ma1, Lu-Lu Sun3
1School of Environmental and Chemical Engineering, Jiangsu University of Science and Technology, Zhenjiang, Jiangsu 212100, China.
Abstract:
Mitochondria are the energy factory of cells and can be easily damaged by reactive oxygen species (ROS) because of the frequent occurrence of oxidative stress. Abnormality in mitophagy is often associated with many diseases including inflammation, cancer, and aging. While previously developed fluorescent probes mainly focus on detecting just ROS or mitophagy, quite rare studies have endeavored to comprehensively capture the entire mitophagic process, encompassing both the production of ROS and the induction of mitophagy. Herein, we report a new ratiometric fluorescent probe NA-DP for tracking peroxynitrite (ONOO-) as well as the subsequent oxidative stress-induced mitophagy. To a naphthalimide-based dye, an ONOO--responsive diphenyl phosphinate moiety and the mitochondria-targeting triphenylphosphonium group were attached. The probe showed a highly selective response to ONOO- through an addition-elimination reaction with diphenyl phosphinate. Owing to its outstanding pH stability and organelle-targeting ability, NA-DP was successfully used to detect mitophagy induced by oxidative stress after the generation of ONOO-. In the meantime, the probe was also used to track starvation-induced mitophagy and indicate that starvation-induced mitophagy is independent of ONOO-. Therefore, NA-DP has the ability to precisely track oxidative stress-induced mitophagy by distinguishing it from starvation-induced mitophagy. This study offers a new chemical tool to study the relationship between ROS generation and mitophagy.
Insights
A new fluorescent probe, NA-DP, tracks peroxynitrite (ONOO-) and subsequent oxidative stress-induced mitophagy. It distinguishes this process from starvation-induced mitophagy, offering a novel tool for ROS research.
Area of Science:
- Cell Biology
- Biochemistry
- Chemical Biology
Background:
- Mitochondria, the cell's energy producers, are vulnerable to damage from reactive oxygen species (ROS) and oxidative stress.
- Dysfunctional mitophagy is implicated in diseases like inflammation, cancer, and aging.
- Existing fluorescent probes often detect either ROS or mitophagy, but rarely the entire process.
Purpose of the Study:
- To develop a novel ratiometric fluorescent probe, NA-DP, for comprehensive tracking of oxidative stress-induced mitophagy.
- To investigate the role of peroxynitrite (ONOO-) in oxidative stress-induced mitophagy.
- To differentiate oxidative stress-induced mitophagy from other mitophagy pathways, such as starvation-induced mitophagy.
Main Methods:
- Design and synthesis of NA-DP, a naphthalimide-based probe incorporating an ONOO--responsive diphenyl phosphinate and a mitochondria-targeting triphenylphosphonium group.
- Characterization of NA-DP's selective response to ONOO- via an addition-elimination reaction.
- Application of NA-DP to detect and track mitophagy induced by oxidative stress and starvation in cellular models.
Main Results:
- NA-DP demonstrated high selectivity and sensitivity for ONOO- detection.
- The probe successfully visualized and tracked mitophagy triggered by oxidative stress following ONOO- generation.
- NA-DP revealed that starvation-induced mitophagy proceeds independently of ONOO-.
Conclusions:
- NA-DP is a versatile ratiometric fluorescent probe capable of precisely tracking oxidative stress-induced mitophagy.
- The probe effectively distinguishes between ONOO--dependent and ONOO--independent mitophagy pathways.
- This study provides a valuable chemical tool for elucidating the complex relationship between ROS production and mitophagy.
