NFAT Responsive Luciferase Reporter NIH/3T3 Stable Cell Line is derived from mouse fibroblast, and stably express firefly luciferase reporter gene under the control of NFAT response element. This cell line is an ideal cellular model for monitoring the activation of Calcium Signaling Pathway triggered by stimuli treatment, enforced gene expression and gene knockdown.
 
NFATs are a family of transcriptional factors that play an important role in immune response as well as in the development of cardiac, skeletal muscle, and nervous systems.  NFATs are regulated by calcium signaling. Through calcium activation of the phosphatase calcineurin, NFATc proteins translocate from the cytoplasm into the nucleus, where they cooperate with other proteins to mediate gene expression. Nuclear import of NFAT is blocked by kinases such as PKA and GSK3. NFATs are also implicated in breast cancer.  Signosis has established a NFAT luciferase reporter cell line that has been stably transfected with a NFAT-luciferase reporter construct. Via the analysis of luciferase, the cell line can be employed to monitor the cellular changes of NFAT activities that are triggered by stimulation, compound treatment, enforced gene expression or gene knockdown. 
 
The cell line is established by transfection using a pTA-NFAT-luciferase reporter vector, which contains NFAT binding sites, 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 PMA+ionomycin-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.