3D structures and ligand specificities of nuclear xenobiotic receptors CAR, PXR and VDR.
The nuclear receptors constitutive androstane receptor (CAR), pregnane X receptor (PXR) and vitamin D receptor (VDR) control a large array of genes that code for important proteins in humans including metabolic enzymes and transporters. 3D structures for the ligand-binding domain (LBD) of these receptors are abundantly available, providing valuable insights into the ligand-binding specificity as well as the activation mechanisms. The ligand-binding site of PXR is large and flexible, whereas those of CAR and VDR are compact and rigid, respectively. In general, the ligand profiles of the receptors are in agreement with the LBD structures. The crystal structures have greatly helped us to understand the promiscuity and/or specificity of CAR, PXR and VDR.
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GENE-Y GENE-Y GENE-Y GENE-Y GENE-N GENE-Y GENE-Y GENE-Y GENE-Y GENE-Y CHEMICAL GENE-Y GENE-Y GENE-Y CHEMICAL CHEMICAL GENE-Y GENE-Y GENE-N GENE-N GENE-N GENE-Y
CAR VDR CAR pregnane X receptor LBD CAR PXR VDR PXR vitamin D receptor androstane CAR PXR VDR pregnane vitamin D VDR constitutive androstane receptor ligand-binding domain LBD nuclear receptors PXR