Healthy tau protein compacts microtubules (IMAGE) University of California - Davis Caption Fluorescence microscopy of self-assembled tau protein envelopes (green) on a microtubule (blue). New research shows that tau envelopes compact the microtubule, changing how areas of microtubule interact with other proteins. Credit UC Davis College of Biological Sciences Usage Restrictions May be used with acknowledgement. License Original 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.