Related Experiment Video
Updated: Jan 7, 2026
Tracking Mouse Bone Marrow Monocytes In Vivo
Published on: February 27, 2015
Real-Time Super-Resolution Tracking of mtDNA Remodeling and Inflammatory Release with a Selective Fluorescent Probe
Shixian Cao1, Caixia Sun2, Xin-Yue Zhang1
1State Key Laboratory of Crystal Materials, Shandong University, Jinan, 250100, China.
Abstract:
Mitochondrial DNA (mtDNA) is vital for mitochondrial function and cellular homeostasis, with its spatiotemporal dynamics are tightly linked to development, metabolism, and disease progression. However, super-resolution tracking of mtDNA in live cells remains limited by lack of selective, photostable small-molecule probes. Here, we present mtNARed, a rationally engineered, wash-free fluorescent probe featuring a large Stokes-shift, and high photostability that enables super-resolution tracking of mtDNA dynamics in live cells using stimulated emission depletion (STED) microscopy, with complementary readouts by fluorescence-lifetime imaging microscopy (FLIM). mtNARed precisely localizes to mitochondrial nucleoids and supports long-term imaging while minimizing interference from nuclear DNA. This capability generalizes across diverse mammalian cell types, including highly polarized sperm cells. Importantly, under mitochondrial stress or inflammatory stimulation, mtNARed reports in situ and at super-resolution of the progressive release of mtDNA, correlating with mitochondrial depolarization, membrane disintegration, and immune activation. This work provides a robust and versatile platform for advanced mtDNA imaging, opening opportunities to dissect mitochondrial genome dynamics, maintenance, and signaling across physiological and pathological states.
Insights
Researchers developed mtNARed, a novel fluorescent probe for tracking mitochondrial DNA (mtDNA) in live cells. This probe enables super-resolution imaging of mtDNA dynamics and release during cellular stress.
Area of Science:
- Cell Biology
- Molecular Biology
- Biophysics
Background:
- Mitochondrial DNA (mtDNA) plays a crucial role in cellular function and homeostasis.
- Tracking mtDNA dynamics in live cells is essential for understanding development, metabolism, and disease.
- Existing methods for live-cell mtDNA imaging are limited by probe selectivity and photostability.
Purpose of the Study:
- To develop a novel, photostable fluorescent probe for super-resolution tracking of mtDNA dynamics in live cells.
- To investigate the spatiotemporal release of mtDNA under various cellular conditions.
- To establish a versatile platform for advanced mtDNA imaging and analysis.
Main Methods:
- Rational engineering of a wash-free fluorescent probe, mtNARed.
- Stimulated emission depletion (STED) microscopy for super-resolution imaging.
- Fluorescence-lifetime imaging microscopy (FLIM) for complementary readouts.
- Imaging across diverse mammalian cell types, including sperm cells.
Main Results:
- mtNARed exhibits a large Stokes-shift and high photostability, enabling long-term live-cell imaging.
- The probe precisely localizes to mitochondrial nucleoids, distinguishing mtDNA from nuclear DNA.
- Super-resolution imaging revealed progressive mtDNA release under mitochondrial stress and inflammation.
- mtDNA release correlated with mitochondrial depolarization, membrane disintegration, and immune activation.
Conclusions:
- mtNARed provides a robust and versatile platform for advanced mtDNA imaging.
- This probe facilitates the study of mitochondrial genome dynamics, maintenance, and signaling.
- The findings open new avenues for dissecting mitochondrial roles in physiological and pathological states.
