Resonance Energy Transfer

About

Background: Interactions between proteins and other molecules play a key regulatory role in almost every biological process. Understanding these interactions is an essential component of basic research and drug development. Researchers in Dr. Sanjiv Sam Gambhir's lab at Stanford University's Molecular Imaging Program have developed a novel system that can be used to monitor protein interactions in both cells and small animals. This Bioluminescence Resonance Energy Transfer (BRET) method utilizes a unique mutant Renilla luciferase gene and a cooled charge-coupled device (CCD) camera, which improves the sensitivity of BRET as a quantitative assay by 40 fold over current methods. Ongoing Research: Researchers are currently evaluating the system for several research tool applications where this system could be used (listed below).   Applications:   Drug development - in vivo and in vitro tool for development of drugs that modulate protein-protein interactions, including: screening compound libraries determining efficacy compound optimization drug validation - transgenic models for quantitative analysis Research tool to monitor cellular events, such as: transcriptional regulation enzyme subunit assembly antigen-antibody reactions reactions with cell-surface receptors protein phosphorylation signal transduction caspase and other protease detection cellular ion exchange Apoptosis sensor in both live cells and small animal models. Transgenic animals - assess protein-protein interactions during embryonic development and maturity.   Advantages:   Quick and easy - allows for faster screening than yeast two-hybrid systems and rapid testing of biological hypotheses and proofs of principle studies in living experimental models. Simultaneous visualization and quantitation - CCD imaging approach of detecting BRET signal allows simultaneous visualization and quantitation. Sensitive - approximately 40 fold improved sensitivity over current BRET systems; this system can detect low levels of signal because the light emitted is virtually free of background. Time resolved imaging - allows visualization and measurement of drug kinetics in vivo. One system for in vitro and in vivo studies - results can be validated using a single instrument. Well-suited for high-throughput imaging - system is easy to operate, has short data acquisition times (typically 10 - 60 sec), and has a large field of view for either 96/384 well plates or up to six mice.