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Updated: May 15, 2026

Reverse Yeast Two-hybrid System to Identify Mammalian Nuclear Receptor Residues that Interact with Ligands and/or Antagonists
10:51

Reverse Yeast Two-hybrid System to Identify Mammalian Nuclear Receptor Residues that Interact with Ligands and/or Antagonists

Published on: November 15, 2013

Nuclear receptors PXR and CAR: implications for drug metabolism regulation, pharmacogenomics and beyond

Xiaojuan Chai1, Su Zeng, Wen Xie

  • 1Zhejiang University, College of Pharmaceutical Sciences, Department of Pharmaceutical Analysis and Drug Metabolism, Hangzhou 310058, China.

Expert Opinion on Drug Metabolism & Toxicology
|January 19, 2013
PubMed
Abstract

Insights

Pregnane X receptor (PXR) and constitutive androstane receptor (CAR) are key nuclear receptors regulating gene expression. Understanding their diverse roles and polymorphisms is crucial for drug development and therapeutic strategies.

Area of Science:

  • Pharmacology
  • Molecular Biology
  • Biochemistry

Background:

  • Nuclear receptors (NRs) are transcriptional factors that regulate gene expression upon ligand binding.
  • Orphan nuclear receptors, including PXR and CAR, play critical roles in xenobiotic and endobiotic metabolism.

Purpose of the Study:

  • To review the transcriptional regulation of P450 genes and other xenobiotic-metabolizing enzymes by PXR and CAR.
  • To discuss the involvement of PXR and CAR in endobiotic metabolism and their polymorphisms.
  • To explore the therapeutic potential of modulating PXR and CAR activity.

Main Methods:

  • Literature review of studies on PXR and CAR.
  • Analysis of transcriptional regulation mechanisms.
  • Examination of PXR and CAR polymorphisms and their implications.

Main Results:

  • PXR and CAR regulate a wide array of target genes, including P450s, UDP-glucuronosyltransferases, glutathione S-transferases, sulfotransferases, and drug transporters.
  • Both receptors are involved in both xenobiotic and endobiotic metabolism.
  • A diverse range of chemicals can activate PXR and CAR, indicating significant cross-talk among xenobiotic receptors.

Conclusions:

  • PXR and CAR are versatile receptors with roles in both foreign compound and endogenous substance metabolism.
  • Polymorphisms in PXR and CAR can influence drug response and disease susceptibility.
  • Targeting PXR and CAR offers potential therapeutic strategies for various diseases and optimizing drug efficacy.

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