Related Experiment Video
Updated: Oct 2, 2026

Reverse Yeast Two-hybrid System to Identify Mammalian Nuclear Receptor Residues that Interact with Ligands and/or Antagonists
Published on: November 15, 2013
Regulation of cyp3a gene transcription by the pregnane x receptor
Bryan Goodwin1, Matthew R Redinbo, Steven A Kliewer
1Nuclear Receptor Systems Research, GlaxoSmithKline Research and Development, Research Triangle Park, NC 27709, USA. bjg90051@gsk.com
Abstract:
The pregnane X receptor (PXR) is a promiscuous nuclear receptor that has evolved to protect the body from toxic chemicals. PXR is activated by a structurally diverse collection of xenobiotics, including several widely used prescription drugs. Various lipophilic compounds produced by the body, such as bile acids and steroids, also activate PXR. PXR stimulates the transcription of cytochrome P450 3A monooxygenases and other genes involved in the detoxification and elimination of these potentially harmful chemicals. Assays that detect PXR activation have important implications for the design of future drugs in two respects. On the one hand, PXR activation assays can be used to determine whether candidate drugs are likely to induce CYP3A gene expression and interact with other medicines. On the other hand, PXR agonists may prove useful in the treatment of diseases in which toxic metabolites accumulate, such as cholestatic liver disease.
Related Concept Videos
Transducer Mechanism: Nuclear Receptors
About 48 different soluble family members of nuclear receptors are identified that can be divided into two main classes:
Pharmacogenetics of Phase I Enzymes: Cytochrome P450 Isozymes
Cell Specific Gene Expression
Regulation of Nuclear Protein Sorting
Regulation of Expression at Multiple Steps
Regulation of the Unfolded Protein Response
