Bioluminescence Resonance Energy Transfer 2 (BRET2)-Based RAS Biosensors to Characterize RAS Inhibitors.

Protein-protein interactions (PPIs) are principle biological processes that control normal cell growth, differentiation, and homeostasis but are also crucial in diseases such as malignancy, neuropathy, and infection. Despite the importance of PPIs in biology, this target class has been very challenging to convert to therapeutics. In the last decade, much progress has been made in the inhibition of PPIs involved in diseases, but many remain difficult such as RAS-effector interactions in cancers. We describe here a protocol for using Bioluminescence Resonance Energy Transfer 2 (BRET2)-based RAS biosensors to detect and characterize RAS PPI inhibition by macromolecules and small molecules. This method could be extended to any other small GTPases or any other PPIs of interest.