Download MendeleyProbing Dominant Negative Behavior of Glucocorticoid Receptor beta through a Hybrid Structural and Biochemical Approach.
Min, J., Perera, L., Krahn, J.M., Jewell, C.M., Moon, A.F., Cidlowski, J.A., Pedersen, L.C.(2018) Mol Cell Biol
- PubMed: 29437838
- DOI: https://doi.org/10.1128/MCB.00453-17
- Primary Citation of Related Structures:
5UC1 - PubMed Abstract:
Glucocorticoid receptor β (GRβ) is associated with glucocorticoid resistance via dominant negative regulation of GRα. To better understand how GRβ functions as a dominant negative inhibitor of GRα at a molecular level, we determined the crystal structure of the ligand binding domain of GRβ complexed with the antagonist RU-486. The structure reveals that GRβ binds RU-486 in the same ligand binding pocket as GRα, and the unique C-terminal amino acids of GRβ are mostly disordered. Binding energy analysis suggests that these C-terminal residues of GRβ do not contribute to RU-486 binding. Intriguingly, the GRβ/RU-486 complex binds corepressor peptide with affinity similar to that of a GRα/RU-486 complex, despite the lack of helix 12. Our biophysical and biochemical analyses reveal that in the presence of RU-486, GRβ is found in a conformation that favors corepressor binding, potentially antagonizing GRα function. This study thus presents an unexpected molecular mechanism by which GRβ could repress transcription.
Organizational Affiliation:
Genome Integrity and Structural Biology Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, North Carolina, USA.
