ACTIVATION OF GLUCOCORTICOID RECEPTOR BY ATP

Glucocorticoid-receptor complex from rat liver cytosol acquired the ability to bind to isolated nuclei when incubated with 5-10 mM ATP at 4°C. This nuclear uptake resulting from the 'activation' of cytosolic glucocorticoid-receptor complex was comparable to the activation achieved by warming the steroid-receptor complex at 23°C. ATP was more effective in causing this transformation when compared with ADP, whereas AMP failed to show any such effect. Both ATP and temperature-caused activation of glucocorticoid receptor was blocked by the presence of 10 mM molybdate. The presence of ATP did not alter the steroid binding properties or the sedimentation characteristics of glucocorticoid receptor under the above conditions. These results suggest a role for ATP in receptor function and offer a convenient method of studying the activation process of glucocorticoid receptor at mild assay conditions. © 1979.