Activity Matters (IMAGE) PLOS Caption Activators (green) bind to DNA sequences (blue) and turn-on gene expression (arrow, upper panel) in young mice. Under these conditions gene expression continues to remain active in adult mice (right, upper panel). On the other hand, unavailability of the activator in young mice turns-off gene expression (left, lower panel), which subsequently leads to changes in gene accessibility (blue, lower right panel), thus disabling activator-to-DNA binding (lower right panel) with gene expression remaining switched-off. Credit Zhu et al. 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.