About me
Development and Application of pH-Sensitive Reporters to Investigate Mitophagy and Mitochondrial Dysfunction in Optic Disease Models
Location: 88
Mentor: Dr. Anh Pham
Mitochondria are essential for cellular function, regulating ATP production, metabolic pathways, and apoptosis. Dysfunctional mitochondria contribute to numerous diseases, including neurodegenerative disorders and glaucoma. Mitophagy, the selective degradation of damaged mitochondria, is crucial for maintaining cellular homeostasis. In this study, we developed and utilized a pH-sensitive fluorescence reporter system to investigate mitophagy dynamics and mitochondrial dysfunction, with a focus on optic disease models. The reporter comprises three mitochondrially targeted fluorophores—mTagBFP2, mApple, and SE-pHluorin (SEP)—each sensitive to distinct pH levels, allowing us to visualize and quantify mitophagy progression.
Fluorescence imaging revealed significant differences between control (H₂O-treated) and DFP-treated groups. In the control group, mitochondria predominantly exhibited green fluorescence, reflecting healthy function and stable pH. In contrast, DFP treatment induced a transition from green to red and blue fluorescence, marking sequential stages of mitophagy. Quantitative analysis using the Mitophagy Colocalization Macro demonstrated increased mitophagy in DFP-treated cells, with pixel intensity ratios distinguishing early and late stages of mitochondrial degradation.
Additional experiments with 143B cells electroporated with the MTreporter confirmed its utility in tracking mitophagy progression with high reproducibility. Ongoing efforts aim to optimize plasmid delivery methods and explore the effects of cellular stress and aging on mitophagy. Future directions include investigating therapeutic interventions to restore mitophagy in neurodegenerative diseases and studying age-related declines in mitochondrial quality control. This research establishes a robust system for studying mitophagy, providing critical insights into mitochondrial turnover and its role in disease progression. The findings offer promising avenues for developing therapies to preserve mitochondrial health and improve cellular function.
