Gene-Switching in Flies (IMAGE) University of Southern California Caption This image shows an example of gene-switching -- in this case, used to drive Green Fluorescent Protein (GFP) expression in the fat tissue of the fly on the right. Credit John Tower / USC Usage Restrictions For use in news stories only License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.