Urea (IMAGE) University of California - Santa Barbara Caption Urea causes tau protein to take on an extended form, while TMAO-exposed tau forms helical structures. Credit Sonia Fernandez 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.