Spindle Experiment (video) Simons Foundation Share Print E-Mail Loading video... Caption Bleached lines in a mixture of microtubules and motors show how microtubules moving in opposite directions glide past each other. All microtubules move at top speed, even those not actively propelled forward. Credit S. Fürthauer et al./ Nature Physics 2019 Usage Restrictions None Share Print E-Mail 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.