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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

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Ligand recognition by drug-activated nuclear receptors PXR and CAR: structural, site-directed mutagenesis and

Antti Poso1, Paavo Honkakoski

  • 1Departments of Pharmaceutical Chemistry and Pharmaceutics, University of Kuopio, P.O. Box 1627, FIN-70211 Kuopio, Finland. Antti.Poso@uku.fi

Mini Reviews in Medicinal Chemistry
|August 22, 2006
PubMed

Insights

Understanding Pregnane X receptor (PXR) and constitutive androstane receptor (CAR) activation is crucial for drug development. This review covers their structures, ligand specificities, and in silico models for predicting activators to minimize drug toxicity.

Area of Science:

  • Pharmacology
  • Molecular Biology
  • Toxicology

Background:

  • Pregnane X receptor (PXR) and constitutive androstane receptor (CAR) are key nuclear receptors regulating drug metabolism and toxicity.
  • These receptors exhibit cross-regulation of target genes and promiscuous activation by diverse ligands, leading to altered drug metabolism and potential toxicity.
  • Understanding PXR and CAR activation is vital for safe drug development.

Purpose of the Study:

  • To review recent advancements in understanding the structural properties of PXR and CAR.
  • To discuss the molecular factors determining ligand and species specificity of PXR and CAR activation.
  • To highlight progress in computational (in silico) models for identifying PXR and CAR activators.

Main Methods:

  • Literature review of recent structural biology studies on PXR and CAR.
  • Analysis of molecular mechanisms underlying ligand binding and species-specific receptor activation.
  • Evaluation of current in silico approaches for predicting PXR and CAR activator potential.

Main Results:

  • Elucidation of PXR and CAR structural features influencing ligand interaction.
  • Identification of key molecular determinants for species-specific receptor activation.
  • Demonstration of progress in developing predictive in silico models for PXR and CAR activators.

Conclusions:

  • Structural insights and molecular understanding are advancing the prediction of PXR and CAR activation.
  • In silico models show promise for identifying potential drug candidates and mitigating toxicity risks.
  • Continued research in this area is essential for optimizing the drug development process.

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