Toxicological profiling with functional nuclear receptor assays
Gaining early insight into the toxicology profile of drug candidates is necessary in an efficient lead selection process to establish safety profiles and reduce preclinical development costs and drug attrition rates. As many pharmaceutical agents act as ligands for nuclear receptors (NRs), toxicology screens often focus on NR-mediated response to small molecules for developing safer therapeutic candidates and minimizing off-target effects.
SwitchGear Genomics offers comprehensive panels of cell-based reporter assays to assist with toxicological evaluation. Our collection of toxicology-relevant promoter reporters consist of known and predicted targets for key nuclear receptors: aryl hydrocarbon receptor (AhR)*, peroxisome proliferator-activated receptors (PPARs), constitutive androstane receptor (CAR), pregnane X receptor (PXR), androgen receptor (AR), estrogen receptor (ER), and glucocorticoid receptor (GR).
Our assay-ready constructs allow you to measure the response of nuclear receptor proteins upon exposure to small molecules by rapidly and reliably measuring NR-mediated transcriptional activity.
Nuclear receptor functional assay workflow
| 1. Expose NR protein to small molecule. | 2. Small molecule binds to ligand binding domain and activates the NR. | 3. Activated NR binds to human promoter and activates or represses transcription. | 4. Promoter activity is measured by luciferase reporter assay allowing functional evaluation of the NR response to a small molecule. |
SwitchGear Promoter Reporter Assay for Nuclear Receptors
| Cell-based reporter assay Expose each well to small molecule |
Selected Promoter Targets of Toxicologically-relevant Nuclear Receptors |
1. Each well has a reporter construct for a different NR target promoter (see panel descriptions).
2. Light signal measures compound effect on the NR-driven response for each human promoter.
3. Top responding promoters can be implemented in a routine screen.
The SwitchGear Advantage
SwitchGear’s nuclear receptor panel of reporter vectors is:
- Quantitative: Measure nuclear receptor activity in response to stimuli using a highly quantitative luciferase assay to measure NR-mediated toxicity.
- Simple and quick: Perform your experiments today through simple transfection of our luciferase reporter constructs. No cloning or DNA preparation is needed.
- Comprehensive and verified: Choose from SwitchGear’s complete set of sequence verified and transfection ready NR targets.
SwitchGear Toxicology-related Nuclear Receptor Panels
We offer the following assay-ready promoter reporters for known and predicted NR targets. Evaluate NR activity from small molecule exposure to help assess toxicity.
| Transcription factor | Number of constructs available |
Example target genes | Known ligands |
| AhR* | 99 | CYP1A1, CYP1B1, GLRX5 | Aromatic hydrocarbons, dioxins, dibenzofurans, biphenyls, bilirubin |
| PPARs | 288 | CCDC51, PLTP | Fatty acids, eicosanoids, prostaglandin, leukotrienes, TZDs |
| PXR/CAR | 112 | CYP3A, CYP2B, CYP2C | Steroids, xenobiotics |
| AR | 79 | PSA, ABCC4, SOCS2 | Testosterone, dihydrotestosterone, 2-quinolones, phthalamides |
| ER | 262 | GAPDH, TFF1, CASP7 | 17-beta-estradiol, estrone, raloxifene, estriol, genistein |
| GR | 182 | SLC38A4, SDPR, SNTA1 | Cortisol, dexamethasone, prednisone, RU486, cyproterone |
*AhR, though not in the nuclear receptor superfamily, is taken into consideration along with nuclear receptors due to its functional similarities. Selection criteria for all constructs include a combination of sequence motif analysis, available published data, as well as ChIP-chip and other binding data.
How to get started
- Review the SwitchGear panels and their corresponding gene lists in SwitchDB to select your promoters of interest.
- Assess the transfection efficiency of your cell line using our Control Constructs (optional).
- Contact us to discuss an affordable pilot study.