The Palindromic DNA-Bound Usp-Ecr Nuclear Receptor Adopts an Asymmetric Organization with Allosteric Domain Positioning.Maletta, M., Orlov, I., Moras, D., Billas, I.M.L., Klaholz, B.P.
(2014) Nat Commun 5: 4139
- PubMed: 24942373
- DOI: 10.1038/ncomms5139
- Structures With Same Primary Citation
- PubMed Abstract:
Nuclear receptors (NRs) regulate gene expression through DNA- and ligand-binding and thus represent crucial therapeutic targets. The ultraspiracle protein/ecdysone receptor (USP/EcR) complex binds to half-sites with a one base pair spaced inverted re ...
Nuclear receptors (NRs) regulate gene expression through DNA- and ligand-binding and thus represent crucial therapeutic targets. The ultraspiracle protein/ecdysone receptor (USP/EcR) complex binds to half-sites with a one base pair spaced inverted repeat (IR1), a palindromic DNA response element (RE) reminiscent of IRs observed for vertebrate steroid hormone receptors. Here we present the cryo electron microscopy structure of the USP/EcR complex bound to an IR1 RE which provides the first description of a full IR-bound NR complex. The structure reveals that even though the DNA is almost symmetric, the complex adopts a highly asymmetric architecture in which the ligand-binding domains (LBDs) are positioned 5' off-centred. Additional interactions of the USP LBD with the 5'-flanking sequence trigger transcription activity as monitored by transfection assays. The comparison with DR-bound NR complexes suggests that DNA is the major allosteric driver in inversely positioning the LBDs, which serve as the main binding-site for transcriptional regulators.
1] Centre for Integrative Biology (CBI), Department of Integrated Structural Biology, IGBMC (Institute of Genetics and of Molecular and Cellular Biology), 1 rue Laurent Fries, 67404 Illkirch, France  Centre National de la Recherche Scientifique (CNRS) UMR 7104, 67404 Illkirch, France  Institut National de la Santé et de la Recherche Médicale (INSERM) U964, 67404 Illkirch, France  Université de Strasbourg, 67404 Strasbourg, France.