Enzyme MEK (IMAGE) Princeton University Caption A ribbon diagram shows the structure of the enzyme MEK and the position of three mutations (called F53, Y130, and E203) that cause disease. Credit Eyan Yeung and Martin Wühr, Princeton University Usage Restrictions Eyan Yeung and Martin Wühr, Princeton University 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.