Antagonist activity at human mineralocorticoid receptor overexpressed in CHOK1 cells assessed as inhibition of aldosterone-induced protein interaction with coactivator peptide after 6 hrs by luminescence assay
Antagonist activity at Gal4 DNA binding domain-tagged human mineralocorticoid receptor ligand binding domain expressed in HEK293 cells assessed as inhibition of receptor-mediated transcriptional activity by luciferase reporter gene assay
Agonist activity at Gal4 DNA binding domain-tagged human mineralocorticoid receptor ligand binding domain expressed in HEK293 cells assessed as activation of receptor-mediated transcriptional activity by luciferase reporter gene assay
Displacement of [3H]-aldosterone from human mineralocorticoid receptor expressed in HEK293 cells by scintillation counting based radioligand competition binding assay
Competitive Molecular Binding Assay: The MR competitive binding assay is based on the binding and displacement of a TAMRA-labeled Dexamethasone probe with fluorescence polarization (FP) detection. The assay is performed in 384-well, low volume NBS black plates (Corning #3676) in assay buffer consisting of 10 mM TES, pH 7.4, 50 mM KCl, 20 mM Sodium molybdate, 1.5 mM EDTA, 0.04% CHAPS, 10% Glycerol and 1 mM DTT. Full Length human mineralocorticoid receptor (hMR) present in a baculovirus infected insect cell lysate is diluted 2 fold in assay buffer and 10 μL of this dilution is added to the assay plate. Blank wells receive 10 μL of the diluted MR lysate containing 3 μM Dexamethasone. 2 μL diluted test compound is transferred to the assay plate for a final starting top concentration of 10 μM in 1% DMSO. The reaction is started by adding 3 μL of 25 nM probe in assay buffer for a final assay concentration of 5 nM.
Receptor Binding Assay: Using cytosol from progesterone receptor-expressing insect cells (Hi5), competitive binding to the progesterone receptor was determined from the ability to displace 3H-progesterone as reference substance from the receptor. If a compound has an affinity corresponding to progesterone, this corresponds to a competition factor (CF) of 1. CF values greater than 1 are characterized by a lower affinity for the progesterone receptor, and CF values of less than 1 are characterized by higher affinity. The test was carried out as test above, with the following modifications: cytosol from mineralocorticoid receptor-expressing insect cells (Hi5) was used, and the reference substance was 3H-aldosterone.
Displacement of [3H]-aldosterone from mineralocorticoid receptor (unknown origin) expressed in HEK293 cell lysate incubated overnight by microbeta scintillation counting method
Antagonist activity against 6xHis-MBP-fused human MR LBD domain (732 to 984 amino acid residues) C808S mutant expressed in Escherichia coli BL21(DE3) assessed as inhibition of aldosterone-mediated receptor activation after 16 hrs by luciferase assay
Displacement of 3H-Cortisol from 6xHis-MBP-fused human MR LBD domain (732 to 984 amino acid residues) C808S mutant expressed in Escherichia coli BL21(DE3) preincubated for 1 hr measured after 30 mins by microbeta plate reader analysis
Agonist activity against 6xHis-MBP-fused human MR LBD domain (732 to 984 amino acid residues) C808S mutant expressed in Escherichia coli BL21(DE3) assessed as receptor activation after 16 hrs by luciferase assay