Figure 1. Clock proteins generating cyanobacterial circadian rhythms (IMAGE) National Institutes of Natural Sciences Caption Circadian rhythms of the phosphorylation cycle (red circle with “P” indicating the phosphor transfer) and the ATP hydrolysis cycle (blue circle with “ATP” and “ADP” indicating the conversion of Adenosine-TriPhosphate into Adenosine-DiPhosphate) can be observed in a test tube. Credit NINS/IMS Usage Restrictions None License Original 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.