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Transcriptional regulation of the human pregnane-X receptor

G Gordon Gibson1, Anna Phillips, Sihem Aouabdi

  • 1University of Surrey, School of Biomedical and Molecular Sciences, Molecular Toxicology Group, England. g.gibson@surrey.ac.uk

Drug Metabolism Reviews
|May 11, 2006
PubMed

Insights

This review explores nuclear receptors and their role in xenosensing, focusing on the pregnane-X receptor (PXR). PXR activation controls genes for drug metabolism, with its promoter elements dictating expression levels.

Area of Science:

  • Biochemistry
  • Molecular Biology
  • Pharmacology

Background:

  • Nuclear receptors are crucial cellular sensors involved in xenobiotic metabolism.
  • The pregnane-X receptor (PXR) plays a key role in regulating genes for drug metabolism, conjugation, and transport.
  • Understanding PXR's transcriptional regulation is vital for drug development and toxicology.

Purpose of the Study:

  • To review the general structure and function of nuclear receptors.
  • To emphasize the role of PXR in xenosensing and xenobiotic metabolism.
  • To detail the transcriptional activation mechanisms of the PXR gene.

Main Methods:

  • Literature review of nuclear receptor function and PXR biology.
  • Analysis of gene regulation pathways involved in drug metabolism.
  • Identification and characterization of regulatory elements in the PXR promoter.

Main Results:

  • Nuclear receptors, particularly PXR, are central to the cellular response to foreign compounds (xenosensing).
  • PXR activation initiates a cascade of gene expression controlling drug metabolism and elimination.
  • Specific positive and negative regulatory elements within the PXR promoter have been identified.
  • The interplay of these promoter elements determines the basal expression level of PXR.

Conclusions:

  • PXR is a critical mediator of drug metabolism and xenobiotic response.
  • Transcriptional regulation of PXR by its promoter elements is a key determinant of its cellular activity.
  • Further research into PXR regulation can inform therapeutic strategies and toxicity assessments.

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