Trapping and characterization of novel retinoid response elements

Area of Science:

• Developmental Biology
• Molecular Genetics
• Genomics

Background:

• Retinoids, like retinoic acid (RA), are crucial for vertebrate development but can cause malformations at excess embryonic doses.
• Retinoids exert their effects by binding to RA receptors and retinoid X receptors, regulating gene expression.
• Distinguishing direct RA-induced genes from downstream effects and identifying functional Retinoic Acid Responsive Elements (RAREs) is challenging due to loosely defined consensus sequences.

Purpose of the Study:

• To develop a functional genomics approach for identifying novel RAREs within the mouse genome.
• To facilitate the discovery of genes directly regulated by retinoid-bound receptors.
• To better understand the molecular mechanisms underlying retinoid signaling in development.

Main Methods:

• A yeast-based system was engineered to "trap" functional RAREs from the mouse genome.
• Candidate RAREs were identified near genes known to be induced by RA.
• Validated RAREs using mammalian reporter gene assays and electrophoretic mobility shift assays (EMSAs).

Main Results:

• The yeast system successfully identified functional RAREs in the mouse genome.
• Several identified RAREs were located proximal to RA-induced genes.
• Functional analyses confirmed these elements as bona fide RAREs.

Conclusions:

• The developed yeast-based functional genomics system is effective for identifying functional RAREs.
• This approach can uncover novel RA-regulated genes and signaling pathways.
• The findings provide a foundation for further investigation into retinoid-mediated gene regulation during development.