PO-ER Interaction (IMAGE) University of Exeter Caption Close interaction of the endoplasmic reticulum (ER) with peroxisomes (PO) in cultured cells is shown by electron microscopy. M, mitochondria. Credit University of Exeter Usage Restrictions This image may only be used in reporting this story 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.