SMAD 2/3 Responsive Luciferase Reporter HepG2 Stable Cell Line is derived from human liver cancer, and stably express firefly luciferase reporter gene under the control of the SMAD 2/3 response element. This cell line is an ideal cellular model for monitoring the activation of TGFbeta pathway Receptor Signaling Pathway triggered by stimuli treatment, enforced gene expression and gene knockdown.
 
SMAD proteins are transcription factors that respond to transforming growth factor-β (TGFβ) signaling, where TGFβ induces its membrane receptors to directly activate Smad proteins. These activated Smads complex with Smad4 (co-Smad), translocate from cytoplasm into nucleus and bind to target promoter region to regulate gene transcriptions. Dysfunction in TGFβ pathway leads to immunosuppression and angiogenesis, which can make cancer more invasive.
 
Signosis has developed SMAD/TGFb luciferase reporter HepG2 stable cell line by co-transfecting SMAD luciferase reporter vector and hygromycin expression vector. The hygromycin resistant clones were subsequently screened for TGFb1-induced luciferase activity. The cell line can be used as a reporter system for monitoring the activation of SMAD triggered by stimuli treatment, such as TGFb1 and TGFb3, and gene overexpression 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.