1h9u
From Proteopedia
The structure of the human retinoid-X-receptor beta ligand binding domain in complex with the specific synthetic agonist LG100268
Structural highlights
FunctionRXRB_HUMAN Receptor for retinoic acid. Retinoic acid receptors bind as heterodimers to their target response elements in response to their ligands, all-trans or 9-cis retinoic acid, and regulate gene expression in various biological processes. The RAR/RXR heterodimers bind to the retinoic acid response elements (RARE) composed of tandem 5'-AGGTCA-3' sites known as DR1-DR5 (By similarity). Specifically binds 9-cis retinoic acid (9C-RA). Evolutionary ConservationCheck, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedLigands that specifically target retinoid-X receptors (RXRs) are emerging as potentially powerful therapies for cancer, diabetes, and the lowering of circulatory cholesterol. To date, RXR has only been crystallized in the absence of ligand or with the promiscuous ligand 9-cis retinoic acid, which also activates retinoic acid receptors. Here we present the structure of hRXRbeta in complex with the RXR-specific agonist LG100268 (LG268). The structure clearly reveals why LG268 is specific for the RXR ligand binding pocket and will not activate retinoic acid receptors. Intriguingly, in the crystals, the C-terminal "activation" helix (AF-2/helix H12) is trapped in a novel position not seen in other nuclear receptor structures such that it does not cap the ligand binding cavity. Mammalian two-hybrid assays indicate that LG268 is unable to release co-repressors from RXR unless co-activators are also present. Together these findings suggest that RXR ligands may be inefficient at repositioning helix H12. The structural basis for the specificity of retinoid-X receptor-selective agonists: new insights into the role of helix H12.,Love JD, Gooch JT, Benko S, Li C, Nagy L, Chatterjee VK, Evans RM, Schwabe JW J Biol Chem. 2002 Mar 29;277(13):11385-91. Epub 2002 Jan 8. PMID:11782480[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
|