Lysosomal-targeted fluorescent probe based pH regulating reactivity for tracking cysteine dynamics under oxidative...

Area of Science:

• Biochemistry
• Cell Biology
• Chemical Biology

Background:

• Cellular events and analytes are crucial for understanding physiological and pathological functions.
• Cysteine (Cys) is vital for biological systems and lysosomal homeostasis, necessitating advanced detection methods.

Purpose of the Study:

• To design and develop a novel coumarin-based probe for the detection of cysteine.
• To achieve reversible, specific, sensitive, and rapid detection of cysteine, particularly within lysosomes.

Main Methods:

• Rational design of a coumarin-based probe (ECMA) incorporating a morpholine moiety for lysosomal targeting.
• Utilizing an α,β-unsaturated-ketone with a CN group as a reversible reaction site for cysteine detection.
• Application of the probe for real-time monitoring of cysteine dynamics in living cells.

Main Results:

• The developed probe (ECMA) demonstrated effective and specific detection of cysteine.
• ECMA enabled real-time monitoring of cysteine dynamics within living cells.
• Cell imaging revealed that exogenous cysteine up-regulates lysosomal reactive oxygen species (ROS).

Conclusions:

• ECMA serves as a powerful tool for investigating the relationship between oxidative stress and lysosomal cysteine.
• The probe facilitates a deeper understanding of cysteine's role in cellular homeostasis and disease.
• This work advances the capability for real-time visualization of biological analytes in cellular environments.