ER and Mitochondria Illustration (IMAGE) University of Colorado at Boulder Caption Electron tomography reveals the three-dimensional structure of membrane contact sites (colored red) between ER tubules (green) and mitochondria (purple) in a yeast cell (right) or an endosome (yellow) in an animal cell (left). Credit Matthew West. 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.