The PolarScreen™ Glucocorticoid Receptor Competitor Assay Kit, Red, provides a sensitive and efficient method for high-throughput, fluorescence polarization-based screening of potential glucocorticoid receptor (GR) ligands. The kit uses insect cell-expressed, human GR (also available separately) and a novel, high-affinity, fluorescent glucocorticoid ligand (Fluormone™ GS Red) in a homogenous, mix-and-read assay format.

This kit produces a red color read-out; a 'green' kit is also available. Both kits suitably determine the IC50s of competitive compounds. Color choice depends on the spectral properties of the compounds to be screened and the available instrumentation. For additional information or assistance, contact drugdiscoverytech@lifetech.com.

The PolarScreen Glucocorticoid Receptor Competitor Assay is:

• Complete & ready-to-use out of the box—all reagents included, just add your test compounds
• High throughput compatible—fluorescence polarization assays in a 384-well plate
• Convenient—components available in bulk sizes for larger screening needs

How the Assay Works
GR is added to a fluorescent glucocorticoid ligand (Fluormone GS Red) in the presence of competitor test compounds in microwell plates. The presence of effective competitors prevents the formation of a GS Red/GR complex, resulting in a decrease of the polarization value. The shift in polarization value in the presence of test compounds is used to determine relative affinity of test compounds for GR. The assay is designed to be carried out at room temperature through use of a coactivator-related stabilizing peptide. Alternatively, the assay may be run at 4°C in the absence of the stabilizing peptide, with insignificant change in GR binding characteristics.

Contact us for bulk quantities or for assistance with other nuclear receptor assay needs, from assay development to library screening and beyond.