No-wash protein labeling with designed fluorogenic probes and application to real-time pulse-chase analysis

Area of Science:

• Biochemistry
• Cell Biology
• Molecular Imaging

Background:

• Small molecule labeling is crucial for understanding cellular protein functions under physiological conditions.
• Existing methods often require washing steps, complicating real-time analysis.
• Developing efficient and non-invasive labeling techniques is essential for biological discovery.

Purpose of the Study:

• To develop a no-wash fluorogenic labeling system for cellular proteins.
• To enable real-time imaging of protein trafficking and dynamics.
• To create a versatile tool for studying protein function in living cells.

Main Methods:

• Utilized fluorescence resonance energy transfer (FRET)-based fluorescein-cephalosporin-azopyridinium probes.
• Employed a mutant beta-lactamase tag for specific protein labeling.
• Engineered probes for fast quencher elimination, hydrophilicity, and resistance to autodegradation.
• Performed real-time pulse-chase analysis to track protein movement.

Main Results:

• Successfully developed a no-wash fluorogenic labeling system.
• Demonstrated efficient labeling and fast quencher elimination.
• Visualized the trafficking of epidermal growth factor receptors in real-time.
• Achieved no-wash fluorogenic labeling of intracellular proteins using membrane-permeable probes.

Conclusions:

• The developed system provides a powerful tool for studying cellular protein dynamics.
• This no-wash approach simplifies experimental procedures and enables live-cell imaging.
• The technology facilitates the discovery of new biological functions through protein labeling.