A Fluorogenic Probe for Cell Surface Phosphatidylserine Using an Intramolecular Indicator Displacement Sensing...

Area of Science:

• Cell biology
• Biochemistry
• Molecular imaging

Background:

• Externalized phosphatidylserine (PS) is a key indicator for distinguishing cell death stages.
• Annexin V-fluorophore conjugates are widely used but have limitations like temperature sensitivity and Ca2+ dependence.

Purpose of the Study:

• To develop a novel, more efficient probe for detecting cell surface PS.
• To overcome the limitations associated with annexin V in apoptosis detection.

Main Methods:

• Development of a fluorogenic probe, P-IID, utilizing an intramolecular indicator displacement (IID) mechanism.
• Evaluation of P-IID performance in fluorescence imaging and flow cytometry.
• Application of P-IID in time-lapse confocal laser scanning microscopy for apoptosis studies.

Main Results:

• P-IID exhibits a fluorescence "turn-on" response upon binding to cell surface PS.
• P-IID demonstrates superior performance over annexin V in both imaging and flow cytometry.
• The probe enables time-lapse imaging of apoptosis in live cells.

Conclusions:

• P-IID is an effective and sensitive probe for detecting cell surface PS.
• The IID mechanism is a viable strategy for developing new live-cell imaging probes.
• P-IID offers advantages for studying apoptosis and other cellular processes involving PS externalization.