AgHalo: A Facile Fluorogenic Sensor to Detect Drug-Induced Proteome Stress

Area of Science:

• Biochemistry
• Cellular Biology
• Drug Discovery

Background:

• Drug-induced proteome stress, including protein aggregation, can lead to adverse effects and compromise drug safety.
• Current safety evaluations rely on cytotoxicity assays that measure cell death, offering limited insight into early-stage proteome stress in live cells.

Purpose of the Study:

• To develop and validate a novel fluorogenic protein sensor for detecting drug-induced proteome stress prior to observable cell death.
• To assess the utility of this sensor in evaluating the safety profiles of common anticancer drugs.

Main Methods:

• Engineered an aggregation-prone Halo-tag mutant (AgHalo) to sense proteome stress via aggregation.
• Utilized a fluorogenic ligand that fluoresces upon AgHalo forming soluble aggregates, enabling detection of conformational changes.
• Applied the sensor to detect differential proteome stress induced by five common anticancer drugs.

Main Results:

• The fluorogenic sensor successfully detected drug-induced proteome stress before any signs of cell death.
• Demonstrated differential proteome stress responses to various anticancer drugs.
• The sensor provides a sensitive readout of cellular stress at a preclinical stage.

Conclusions:

• The developed fluorogenic sensor offers a new paradigm for drug safety assessment by detecting proteome stress before cell death.
• This approach expands the current capabilities of safety evaluation, complementing existing cytotoxicity assays.
• The sensor has broad applicability for detecting proteome stress induced by various toxins and chemicals.