Crystallization of the human glucocorticoid receptor ligand binding domain: a step towards selective glucocorticoids.

The crystal structure of the glucocorticoid receptor (GR) ligand binding domain in a ternary complex with dexamethasone and a TIF2 coactivator peptide has been determined recently. The structure reveals several distinct features not found in other nuclear receptors, such as a novel dimerization interface and a second charge clamp that might be important in determining coactivator binding selectivity. The GR ligand binding domain also has a steroid binding pocket that is distinct from other nuclear receptors and might explain its selectivity for glucocorticoids and its diversity of responses.