Katanin Severing Straying Microtubules (video) Washington University in St. Louis Loading video... Caption A short movie clip shows a single severing event. The microtubule array is fluorescent green and the microtubules' growing tips are marked red. The white arrow follows the growing tip of one microtubule as it crosses over existing microtubules. A pink arrow appears when a crossover is cut. The microtubule disintegrates behind the cut and disappears. Credit Dixit Lab 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.