Estrogen Receptor Alpha (ERα; ESR1; NR3A1)
These ERα Reporter Assay Systems utilize non-human mammalian cells engineered to express constitutive, high-level expression of the full length Human Estrogen Receptor 1 (NR3A1), a ligand-dependent transcription factor commonly referred to as ERα.
ER-alpha is encoded by the human gene ESR1 (EStrogen Receptor 1).The estrogen receptor (ESR) is a ligand-activated transcription factor composed of several domains important for hormone binding, DNA binding, and activation of transcription. Alternative splicing results in several ESR1 mRNA transcripts, which differ primarily in their 5-prime untranslated regions. The translated receptors show less variability.
INDIGO's Reporter Cells include the luciferase reporter gene functionally linked to an ERα-responsive promoter. Thus, quantifying changes in luciferase expression in the treated reporter cells provides a sensitive surrogate measure of the changes in ERα activity. Luciferase gene expression occurs after ligand-bound ERα undergoes nuclear translocation, DNA binding, recruitment, and assembly of the co-activators and accessory factors required to form a functional transcription complex, culminating in expression of the target gene. Unlike some other cell-based assay strategies, the readout from INDIGO's reporter cells demands the same orchestration of all intracellular molecular interactions and events that can be expected to occur in vivo.
For more information on ERα, visit the Nuclear Receptor Resource.
Kits are offered in different assay formats to accommodate researchers’ needs: 3 x 32, 1 x 96, and 1 x 384 assay formats for screening small numbers of test compounds, as well as custom bulk reagents for HTS applications. Assay systems are all inclusive, providing reporter cells, optimized growth media, media for diluting test compounds, a positive-control agonist, luciferase detection reagent, a white assay plate, a detailed protocol, and a protocol quick guide. All kits are shipped on dry ice.
ER Alpha 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.
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 estrogen receptor alpha. This kit product is an all-inclusive assay system that includes, in addition to ER Alpha 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.
| Product Family | Product Number | Product Description |
| IB0040 ERα (NR3A1) | IB00401-32 | Human ERα Reporter Assay System, 3 x 32 assays in 96-well format |
| IB00401 | Human ERα Reporter Assay System, 1 x 96-well format assays | |
| IB00402 | Human ERα Reporter Assay System, 1 x 384-well format assays |
Service Assays: Human
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. To initiate a Service Study, download and complete all fields of the Excel worksheet “Service Work Order" then submit the electronic file to INDIGO Customer Service.
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Novel synthesised flavone derivatives provide significant insight into the structural features required for enhanced anti-proliferative activity
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ABSTRACT Breast cancer cells express enzymes that convert cholesterol, the synthetic precursor of steroid hormones, into estrogens and androgens, which then drive breast cancer cell proliferation. In the present study, we sought to determine whether oxidosqualene cyclase (OSC), an enzyme in the cholesterol biosynthetic pathway, may be targeted to suppress progression of breast cancer cells. In previous studies, weRead More
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Probing the human estrogen receptor-a binding requirements for phenolic mono- and di-hydroxyl compounds: A combined synthesis, binding and docking study
ABSTRACT Various estrogen analogs were synthesized and tested for binding to human ERα using a florescence polarization displacement assay. Binding affinity and orientation were also predicted using docking calculations. Docking was able to accurately predict relative binding affinity and orientation for estradiol, but only if a tightly bound water molecule bridging Arg394/Glu353 is present. Di-hydroxylRead More
Structural Stereochemistry of Androstane Hormones Determines Interactions with Human Androgen, Estrogen, and Glucocorticoids Receptors
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