Nuclear receptors orchestrate detoxification pathways

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Updated: Sep 26, 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

Jayanta Roy-Chowdhury1, Joseph Locker, Namita Roy-Chowdhury

  • 1Albert Einstein College of Medicine, Bronx, NY 10461, USA.

Developmental Cell
|May 10, 2003
PubMed

Insights

New research reveals that pregnane X receptor (PXR) and constitutive androstane receptor (CAR) regulate natural detoxification. These nuclear receptors coordinate bilirubin processing, including storage, glucuronidation, and transport.

Area of Science:

  • Biochemistry
  • Molecular Biology
  • Pharmacology

Background:

  • Nuclear receptors pregnane X receptor (PXR) and constitutive androstane receptor (CAR) are established regulators of xenobiotic detoxification enzymes.
  • Their precise roles in natural endogenous detoxification pathways are less understood.

Purpose of the Study:

  • To investigate the involvement of PXR and CAR in the natural detoxification process of bilirubin.
  • To elucidate the mechanisms by which these receptors coordinate bilirubin metabolism and transport.

Main Methods:

  • The study likely involved molecular biology techniques to analyze gene and protein expression.
  • Assays to measure bilirubin levels and transport activity in cellular or animal models were probably employed.

Main Results:

  • PXR and CAR were found to extend their regulatory roles beyond xenobiotics to natural detoxification processes.
  • These receptors were shown to coordinate the induction of key proteins involved in bilirubin storage, glucuronidation, and canalicular transport.

Conclusions:

  • PXR and CAR are critical regulators of endogenous bilirubin detoxification.
  • These findings expand the known physiological functions of PXR and CAR in maintaining metabolic homeostasis.

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