ER Stress-ERSE Luciferase Reporter MEF Stable Cell Line is derived from murine embryonic fibroblast, and stably express firefly luciferase reporter gene under the control of ERSE (ER stress response element). This cell line is an ideal cellular model for monitoring the activation of ER Stress Signaling Pathway triggered by stimuli treatment, enforced gene expression and gene knockdown.
 
The endoplasmic reticulum (ER) is responsible for properly folding and processing secreted and transmembrane proteins. Any factors that disrupt this function may cause an accumulation of misfolded and unfolded proteins in the ER, a condition known as ER stress. Upon ER stress a signaling network called the Unfolded Protein Response (UPR) will be initiated to eliminate this stress and restore ER homeostasis. In case of failure however, the UPR promotes apoptosis. ER stress play role in many chronic diseases like diabetes, neurodegeneration and cancer. Researchers have to measure mRNA or protein expression in order to study ER stress or UPR.

Signosis has developed a luciferase reporter stable cell line with ERSE (ER stress response element) that can be easily used to monitor ER stress in the cell. Under conditions of ER stress, ER stress-responsive proteins bind to the ERSE, resulting in the transcriptional induction of luciferase gene.
 
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.