A quantitative TR-FRET plate reader immunoassay for measuring autophagy.

Area of Science:

• Cell Biology
• Molecular Biology
• Biochemistry

Background:

• Autophagy is crucial for cellular homeostasis, involving the degradation of cellular components via lysosomes.
• Dysregulation of autophagy is linked to various diseases, highlighting the need for accurate quantification methods.
• Existing methods like immunoblotting and imaging have limitations in objectivity and scalability.

Purpose of the Study:

• To develop a facile, quantitative, and scalable assay for measuring cellular autophagic activity.
• To overcome limitations of traditional autophagy detection methods.
• To enable high-throughput screening of autophagy modulators and autophagic flux.

Main Methods:

• Generation of a quantitative plate reader assay using Time-Resolved Fluorescence Resonance Energy Transfer (TR-FRET).
• Utilized GFP-tagged LC3B (microtubule-associated protein 1A/1B-light chain 3 B) as a TR-FRET acceptor.
• Screened and identified a specific antibody with preferential affinity for the lipidated LC3B-II form.

Main Results:

• Developed a TR-FRET immunoassay for quantifying autophagic activity based on LC3B-II detection.
• The assay provides quantitative and objective results, surpassing traditional methods.
• Demonstrated the assay's utility in detecting changes in autophagy and estimating autophagic flux.

Conclusions:

• The TR-FRET immunoassay offers a robust, scalable, and automation-friendly platform for autophagy research.
• This method facilitates quantitative assessment of autophagic activity and flux.
• The assay is suitable for high-throughput screening applications in drug discovery and disease research.