Open Protein (IMAGE) Oregon Health & Science University Caption The motions of a protein are intimately tied to its function(s). Pictured here is the protein arginine kinase, which is similar to the human protein creatine kinase. It's involved in storing and retrieving energy from a 'bank' in cells when the need arises. For example, if you see a lion and you need your heart to beat faster so that you can run, this protein helps obtain the needed extra energy. When the protein opens (figure 1), it binds to specific molecules in a cell. That then causes the protein to close (figure 2), which begins a chemical reaction between the bound molecules. After the reaction is complete, the protein then opens again, and the new molecules leave the protein. You can view the proteins’ motions in the simulation. Credit Omar Davulcu, Ph.D., OHSU 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.