Molecular Spies Report on AMPK Activity (IMAGE) Johns Hopkins Medicine Caption The "molecular spies" report AMPK activity in red and yellow. It is active to different degrees in different cellular compartments (top, bottom) and not active at all in cells missing AMPK (right). ER, endoplasmic reticulum. Credit Inoue Lab, Johns Hopkins Medicine 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.