Mineralocorticoid Receptor (MR; NR3C2)

Product Family	Product Number	Product Description	Technical Manual
IB0050 MR (NR3C2)	IB00501-32	Human MR Reporter Assay System, 3 x 32 assays in 96-well format	Technical Manual
	IB00501	Human MR Reporter Assay System, 1 x 96-well format assays	Technical Manual
	IB00502	Human MR Reporter Assay System, 1 x 384-well format assays

Mineralocorticoid Receptor Background

The mineralocorticoid receptor (MR), also called aldosterone receptor, is a receptor with high affinity for mineralocorticoids. It belongs to the steroid hormone receptor family where the ligand diffuses into cells, interacts with the receptor, and results in a signal transduction affecting specific gene expression in the nucleus. The gene for the NR3C2 (located on chromosome 4q31.1-31.2) encodes for the 107 kDa MR protein.

MR is expressed in many tissues, such as the kidney, colon, heart, central nervous system (hippocampus), brown adipose tissue, and sweat glands. In epithelial tissues, its activation leads to the expression of proteins regulating ionic and water transports (mainly the epithelial sodium channel or ENaC, Na+/K+ pump, serum and glucocorticoid induced kinase or SGK1) resulting in the reabsorption of sodium, and as a consequence an increase in extracellular volume, increase in blood pressure, and an excretion of potassium to maintain a normal salt concentration in the body.

The receptor is activated by mineralocorticoids such as aldosterone and deoxycorticosterone as well as glucocorticoids, like cortisol and cortison. It also responds to some progestins. Spironolactone and eplerenone are mineralocorticoid receptor antagonists. Activation of the mineralocorticoid receptor, upon the binding of its ligand aldosterone, results in its translocation to the cell nucleus, homodimerization and binding to hormone response elements present in the promoter of some genes. This results in the complex recruitment of the transcriptional machinery and the transcription into mRNA of the DNA sequence of the activated genes.

INDIGO's Mineralocorticoid Receptor Reporter Assay Systems utilize proprietary mammalian cells engineered to express human NR3C2 protein, commonly referred to as MR.

The principle application of this assay product is in the screening of test samples to quantify functional activities, either agonist or antagonist, that they may exert against the human mineralocorticoid receptor.

For more information on MR, visit the Nuclear Receptor Resource.

Synonyms: Mineralocorticoid Receptor, MR, Human Mineralocorticoid Receptor, Human MR, NR3C2

Mineralocorticoid Receptor Assay Kit

This Mineralocorticoid Receptor (MR) kit is an all-inclusive assay system that includes, in addition to MR Reporter Cells, two optimized media for use during cell culture and (optionally) in diluting the test samples, a reference agonist, Luciferase Detection Reagent, a cell culture-ready assay plate, and a detailed protocol.

MR Reporter Cells are prepared using INDIGO’s proprietary CryoMite™ process. This cryo-preservation method yields high cell viability post-thaw, and provides the convenience of immediately dispensing healthy, division-competent reporter cells into assay plates. There is no need for intermediate spin-and-wash steps, viability determinations, or cell titer adjustments.

INDIGO’s assay kits feature a luciferase detection reagent specially formulated to provide stable light emission between 5 and 90+ minutes after initiating the luciferase reaction. Incorporating a 5-minute reaction-rest period ensures that light emission profiles attain maximal stability, thereby allowing assay plates to be processed in batch. By doing so, the signal output from all sample wells, from one plate to the next, may be directly compared within an experimental set.

Kits are offered in different assay formats to accommodate researchers’ needs: 3x 32, 1x 96, and 1x 384 assay formats for screening small numbers of test compounds, as well as custom bulk reagents for HTS applications.

Assay Kit & Platforms

Bulk assay reagents can be custom manufactured to accommodate any scale of HTS. Please inquire.

Mineralocorticoid Receptor Assay Services

The primary application of INDIGO’s cell-based nuclear receptor assays are to quantitatively assess the bioactivity of a test compound as an agonist (activator) or antagonist (inhibition of an agonist response) of a given receptor. Service assays include a positive control reference compound and ‘vehicle’ control for every experiment. A formal study report and all data files are provided to the client upon completion of the study. To receive a quote for your proposed study, complete & submit the online “Request a Quote” form or contact an INDIGO Customer Service Representative to discuss your desired study parameters.