Promega NanoBRET Protein Interaction Assays

Promega has launched NanoBRET Protein Interaction Assays, which use bioluminescence resonance energy transfer (BRET) technology to enable scientists to quantitatively measure protein:protein interactions in live cells.

Traditional methods for studying interactions between proteins are commonly performed in vitro using only protein fragments and do not provide data in the context of the cellular environment. The protein interaction assays enable researchers to study both induction and inhibition of protein interactions in real time using full-length proteins expressed at physiologically relevant levels.

Conventional BRET measures the interaction of proteins using a bioluminescent donor fused to a protein of interest and a fluorescent acceptor fused to its binding partner; the donor does not excite the fluorophore using light, but transfers resonance energy through dipole-dipole coupling. The optimised protein interaction assays use NanoLuc Luciferase as the energy donor and HaloTag protein as the energy acceptor.

NanoBRET technology is claimed to feature improved spectral overlap, increased signal and lower background, providing researchers with a reproducible method for monitoring and screening protein interactions. The brighter light output from NanoLuc enables use of the assays even at low expression levels while still providing efficient energy transfer.