Constitutive Androstane Receptor-3 (CAR-3; NR1I3i3)
INDIGO’s Human Constitutive Androstane Receptor, isoform 3 (CAR3) Reporter Assay System utilizes proprietary mammalian cells engineered to provide high-level expression of human CAR3 (NR1I3 isoform 3), a ligand-activated transcription factor. The Reporter Cells utilize a modified version of human CAR3 in which the N-terminal DNA binding domain (DBD) has been replaced with the GAL4-DBD. The human CAR3 ligand binding domain (LBD) is unaltered and fully functional. Reporter cells also incorporate a luciferase cDNA functionally linked to the GAL4-upstream activation sequence (UAS). Thus, quantifying expressed luciferase activity provides a sensitive surrogate measure of changes in CAR3 activity resulting from a direct interaction between a treatment compound and the nuclear receptor. Because this assay system expresses a GAL4-DBD + hCAR3 LBD hybrid receptor, the bio-activity of activators that act through indirect mechanisms (such as those that alter the phosphorylation status of the native N-terminal amino acid sequence of CAR3) may be dampened or go undetected.
Human CAR 3 is not constitutively active, rather, it exhibits ligand-dependent activation. The primary application of this reporter assay system is in the screening of test samples to quantify any functional activity, either agonist or antagonist, that they may exert on human CAR3.
Unlike most nuclear receptors, this transcriptional regulator is constitutively active in the absence of ligand but is regulated by both agonists and inverse agonists. Ligand binding results in translocation of this protein to the nucleus, where it activates or represses target gene transcription. These ligands include bilirubin, a variety of foreign compounds, steroid hormones, and prescription drugs.
For more information on CAR, visit the Nuclear Receptor Resource.
Also available in: Mouse
CAR3 Reporter Cells are prepared using INDIGO’s proprietary CryoMite™ process. This cryo-preservation method yields exceptional cell viability post-thaw, and provides the convenience of immediately dispensing healthy, division-competent reporter cells into assay plates. There is no need for cumbersome intermediate treatment steps such as spin-and-rinse of cells, viability determinations, cell titer adjustments, or pre- incubation of reporter cells prior to assay setup.
|Product Family||Product Number||Product Description|
|IB0090 CAR-3 (NR1I3)||IB00901-32||Human CAR-3 Reporter Assay System, 3 x 32 assays in 96-well format|
|IB00901||Human CAR-3 Reporter Assay System, 1 x 96-well format assays|
|IB00902||Human CAR-3 Reporter Assay System, 1 x 384-well format assays|
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.
Sedaxane—Use of Nuclear Receptor Transactivation Assays, Toxicogenomics, and Toxicokinetics as Part of a Mode of Action Framework for Rodent Liver Tumors
ABSTRACT Experimental data demonstrate a mode of action (MOA) for liver tumors in male rats and mice treated with sedaxane that starts with activation of CAR, followed by altered expression of CAR-responsive genes, increased cell proliferation, and eventually clonal expansion of preneoplastic cells, leading to the development of altered foci and tumors. This MOA is
View Full Size Research conducted by: Koji Toyokawa (1), Ewa Maddox (1), Jack Vanden Huevel (1,2), & Bruce Sherf (1) (1) INDIGO Biosciences, Inc., 1981 Pine Hall Rd, State College, PA, USA (2) Center for Molecular Toxicology and Carcinogenesis, 325 Life Sciences Building, Penn State University, University Park, PA 16802, USA Date of Publication: 2017
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Mouse Liver Tumor Mode of Action: Use of Toxicogenomics in Weight of Evidence for Human Relevance Assessment
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