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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

Published on: November 16, 2013

Orphan nuclear receptors: from new ligand discovery technologies to novel signaling pathways

A K Shiau1, P Coward, M Schwarz

  • 1Tularik Inc., Two Corporate Drive, South San Francisco, CA 94080, USA.

Current Opinion in Drug Discovery & Development
|June 27, 2003
PubMed

Insights

Biochemical assays identify ligands for orphan nuclear receptors by detecting coactivator recruitment. These ligands reveal new signaling pathways and have potential clinical applications.

Area of Science:

  • Molecular Biology
  • Endocrinology
  • Genetics

Background:

  • Nuclear receptors are crucial transcription factors regulating development, differentiation, and homeostasis.
  • Their function is modulated by interactions with transcriptional coactivators, influenced by receptor agonists and antagonists.
  • Orphan nuclear receptors lack known endogenous ligands, posing a challenge for functional studies.

Purpose of the Study:

  • To review the application of coactivator recruitment assays in identifying ligands for orphan nuclear receptors.
  • To highlight the discovery of novel biological signaling pathways mediated by these identified ligands.
  • To discuss the potential clinical implications of targeting these nuclear receptor-ligand interactions.

Main Methods:

  • Utilizing biochemical assays that measure ligand-binding through coactivator recruitment.
  • Applying these assays to orphan nuclear receptor subfamilies, including liver X receptor, farnesoid X receptor, and estrogen receptor-related receptors.
  • Analyzing the identified ligands for their role in uncovering new biological signaling.

Main Results:

  • Successful identification of naturally occurring and synthetic ligands for several orphan nuclear receptors.
  • Demonstration of how these ligands facilitate the discovery of previously unknown biological signaling pathways.
  • Evidence suggesting potential therapeutic applications for the identified ligands and pathways.

Conclusions:

  • Coactivator recruitment assays are powerful tools for discovering ligands for orphan nuclear receptors.
  • Ligand identification has significantly advanced our understanding of nuclear receptor-mediated signaling.
  • Targeting these newly discovered pathways holds promise for future clinical interventions.

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