Screening tool amplifies tiny changes in protein levels within cells

Scientists have developed a new screening tool that can detect minute changes in protein levels within cells, similar to how one might spot a few missing grains of sand in two otherwise identical sandcastles. This tool, created by researchers led by Steven Banik, an assistant professor of chemistry, offers a way to visualize tiny fluctuations in protein levels, which can indicate a shift between a healthy state and disease, or the effectiveness of a drug.

Proteins, the molecular machines inside cells, perform crucial functions, and even slight decreases in their levels can significantly impact cellular behavior. Traditional methods of studying protein abundance are often labor-intensive and sensitive, requiring large quantities of cells and multiple rounds of concentration. The new method developed by Banik's team uses signal amplification to make even small changes in protein levels visible, enabling scientists to conduct high-throughput screens and analyze hundreds of proteins and drugs simultaneously.

This breakthrough was achieved through a combination of technical expertise and cellular engineering, involving the fusion of target proteins to a molecular brake and a transcription factor that acts as a cellular gas pedal. When the protein-brake fusion degrades, the gas pedal propels the cellular machinery to produce increasingly bright fluorescent signals that can be easily measured and visualized.

The tool's tunability allows for independent control of multiple fluorescent outputs or even the addition of an RNA barcode for sequencing, offering a versatile platform for studying protein dynamics and their roles in biological processes or disease pathology.