Glucocorticoid receptors lacking hormone-binding activity are bound in nuclei of ATP-depleted cells

Abstract

The glucocorticoid receptor binding capacity of rat thymus cells disappears when the cells are depleted of ATP by anaerobiosis, and rapidly reappears when ATP levels are restored^1–3. Loss and recovery of binding capacity occurs even when protein synthesis is suppressed with cycloheximide^3,4. In view of this and similar work in other cell systems^5,6, we proposed that in cells deprived of ATP the receptor is present in a form—the ‘null receptor’ form, as we shall call it—that cannot bind hormone⁴. Although many subsequent observations support this idea, no direct evidence has appeared for the existence of the null receptor. We have attempted to detect the null receptor in WEHI-7 mouse thymoma cells with a monoclonal antibody to the glucocorticoid receptor. Here we report that the null receptor is bound in the nuclei of ATP-depleted cells, and is present in amounts comparable to those of receptors in normal cells.