Mutated Protein in Lou Gehrig’s Disease (IMAGE) University of Pennsylvania School of Medicine Caption The top image is of yeast expressing FUS. Note the presence of FUS clumps in the cytoplasm (green foci) and the position of the nucleus (blue). The bottom image is an electron microscopy image of clumps formed by pure FUS in the test tube. Credit Aaron Gitler, PhD, James Shorter, PhD, University of Pennsylvania School of Medicine Usage Restrictions None 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.