Light-Up Lipid Droplets Dynamic Behaviors Using a Red-Emitting Fluorogenic Probe.

Area of Science:

• Cell Biology
• Biochemistry
• Molecular Imaging

Background:

• Intracellular lipid metabolism is essential for cell survival and occurs within lipid droplets (LDs).
• Visualizing LDs in live cells is crucial for understanding their physiological roles.
• Current imaging techniques are limited by the availability of specific and robust probes for LD visualization in vivo.

Purpose of the Study:

• To develop and characterize a novel red-emitting probe for specific and efficient imaging of intracellular lipid droplets (LDs).
• To evaluate the probe's performance in terms of signal-to-noise ratio, Stokes shift, and photobleaching resistance.
• To demonstrate the probe's utility in real-time tracking of LD dynamics in live cells.

Main Methods:

• Synthesis and characterization of a novel red-emitting fluorescent probe targeting lipid droplets.
• In vitro and in vivo assessment of the probe's photophysical properties, including signal-to-noise ratio, Stokes shift, and photostability.
• Live-cell imaging experiments to monitor intracellular LD behaviors such as fusion, migration, and lipophagy.

Main Results:

• The developed probe exhibits an ultrahigh signal-to-noise ratio and a large Stokes shift (up to 214 nm).
• The probe demonstrates superior resistance to photobleaching compared to existing methods.
• Successful real-time tracking of dynamic LD processes, including fusion, migration, and lipophagy, was achieved using the probe.

Conclusions:

• The novel red-emitting probe provides an advanced tool for high-quality in vivo imaging of lipid droplets.
• This probe facilitates a deeper understanding of LD-associated behaviors and their roles in cellular metabolism.
• The probe aids in distinguishing between adaptive lipid storage and lipotoxicity, offering new avenues for research.