Tubulin Cap Stablizes Microtubule (video) University of California - Berkeley Loading video... Caption This video shows how the constant addition of tubulin bound to GTP provides a cap that prevents the microtubule from falling apart. UC Berkeley scientists found that the hydrolyzation of GTP to GDP (change of red to violet) compacts the tubulin into a strained configuration that rapidly peels the microtubule apart if the cap disappears. Credit Eva Nogales lab, UC Berkeley Usage Restrictions None 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.