Stanford researchers have developed a novel system to detect estrogen receptor (ER) binding by both agonists and antagonists. Unlike previous assays that relied on indirect identification of ER activity (e.g. ER promoter activity or cofactor recruitment), this novel technology is based upon the intramolecular folding of the ER. The scientists fused the ER between N-terminal and C-terminal fragments of Renilla luciferase or Firefly luciferase. Binding of the ER causes a structural change that brings the two terminal fragments into close proximity of one another, which allows the two fragments to complement one another and produce light. This interaction can be measured and quantified. Importantly, this method is able to distinguish between ER agonists and antagonists as they provide different characteristics for the amount of light emitted. Importantly, the inventors have created a transgenic mouse permitting the study of ER ligands in vivo. [ - ]

Stanford researchers have developed a novel system to detect estrogen receptor (ER) binding by... [ + ]