Promega NanoLuc NanoBRET target engagement technology

Promega NanoLuc technology has been used to directly assess the dynamic process of target engagement in live cancer cells. The company’s scientists have developed a method for use in drug discovery that measures target residence as a key aspect of target engagement in live cells. The technology uses bioluminescence resonance energy transfer (BRET) and allows measurement of drug binding to protein targets in real time and within live cells.

Measuring target protein-drug occupancy in cells and correlating this target engagement with desired pharmacologic effects is important in drug discovery. NanoBRET technology provides a simple method to directly assess target engagement. It also offers the ability to measure target residence time — the duration of drug-protein interaction — allowing researchers to optimise drugs for enhanced action despite clearance from the system.

To detect drug-target interactions, NanoBRET target engagement uses cell-permeable fluorescent tracers designed to interact with NanoLuc-tagged target proteins. The result of interaction is energy transfer from the NanoLuc protein to the tracer, generating a measurable signal. If a small molecule drug candidate interacts with the target protein, the tracer and drug compete for binding and BRET signal diminishes. Residence time measurement relies on pre-equilibration of compound with cells, removal of excess compound and addition of tracer. Real-time signal monitoring shows compounds with slow target dissociation impede tracer binding and slow BRET signal production.