Patent 7691564 was granted and assigned to Johns Hopkins University on April, 2010 by the United States Patent and Trademark Office.
Receptor mediated activation of heterotrimeric G-proteins is visualized in living cells by monitoring fluorescence resonance energy transfer (FRET) between subunits of a G protein fused to cyan and yellow fluorescent proteins. The G-protein heterotrimer rapidly dissociates and reassociates upon addition and removal of cognate ligand. Energy transfer pairs of G-proteins enables direct in situ detection and have applications for drug screening and GPCR de-orphaning.