XRE Luciferase Reporter HEK293 Stable Cell Line is derived from human embryonic kidney, and stably expresses firefly luciferase reporter gene under the control of the Xenobiotic response element (XRE). This cell line is an ideal cellular model for monitoring the cellular response to stress-related pathways.
 
Xenobiotic response element (XRE) is a DNA binding sequence at the upstream of inducible target genes for the transcription factor aryl hydrocarbon receptor (AhR) that is responsible for regulation of stress pathway in eukaryotic cells. The AhR regulates response to xenobiotic toxicity from variety of chemicals like 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). The AhR functions as a ligand-activated transcription factor that binds to a canonical xenobiotic response element (XRE) in association with the heterodimerization partner, the AhR nuclear translocator (Arnt) protein.
 
Signosis has established XRE luciferase reporter HEK293 stable cell line that has been stably transfected with XRE-luciferase reporter vector and can be used for studying TCDD toxicity and most cellular stress-related responses. The cell line was established by transfection using a XRE-luciferase reporter vector, which contains 4 repeats of Xenobiotic response element (XRE), a minimal promoter upstream of the firefly luciferase coding region, along with hygromycin expression vector followed by hygromycin selection. The hygromycin resistant clones were subsequently screened for TCDD-induced luciferase activity.
 
Principle behind TF luciferase reporter. TF luciferase reporter stable cell line utilizes artificial promoter constructs to drive luciferase expression. The promoter region can consists of multiple repeats of a cis-element TF binding site, a DNA fragment from the promoter region of a known TF downstream gene, or a DNA fragment containing putative/known TF binding sites. There are several ways that a TF can be activated, such as through extracellular stimuli or through intracellular signaling pathways. Once activated, the TF translocates to the nucleus and often interacts with relevant co-factors to drive gene expression. Once luciferase is expressed, it can generate light in an enzymatic assay and the amount of light measured is positively correlated with the level of TF activation.