TCF/LEF Responsive Luciferase Reporter HEK293 Stable Cell Line is derived from human embryonic kidney, and stably express firefly luciferase reporter gene under the control of the TCF/LEF response element. This cell line is an ideal cellular model for monitoring the activation of Wnt/b-catenin  Receptor Signaling Pathway triggered by stimuli treatment, enforced gene expression and gene knockdown.
 
The Wnt signaling pathway is important to both embryonic development and tumorigenesis. β-Catenin, the central component of the pathway, functions as a co-factor of the TCF/LEF family of transcription factors. Together, they activate transcription of Wnt target genes by binding to the promoters of downstream target genes involved in cell proliferation, survival, and migration. 
 
Signosis has established a TCF/LEF luciferase reporter stable cell line that has been stably transfected with pTA-TCF/LEF-luciferase reporter vector, which contains 6 repeats of TCF/LEF binding sites, a minimal promoter upstream of the firefly luciferase coding region. Therefore, the cell line can be used as a reporter system for monitoring the activation of β-catenin triggered by stimuli treatment, enforced gene expression and gene knockdown.
 
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.