Figure 14 HTRF strategy for detection and quantification of interaction between receptor and coactivator.

Known agonists have been shown previously to activate ligands for PPARγ in mammalian cell-based assays [24]. Using the HTRF assay approach described above, increasing concentrations of thiazolidinediones (TZDs) were added to reaction mixtures. Figure 15 shows that TZDs induced a dose-dependent, specific interaction between PPARγ-LBD and the nuclear receptor binding domain of CBP with similar EC50s values obtained by transactivation studies. This assay indicates that HTRF assay methods can provide a powerful alternative to cell-based assays for screening large compound libraries for potential agonist drug candidates [25].