Smad3 Transcription Factor Activity Assay

Built around the biology of TGF-β signaling, this Smad3 Transcription Factor Activity Assay from Assay Genie quantifies the DNA-binding competence of Smad3 rather than its overall expression level. Smad3 is a central intracellular effector of TGF-β receptors, translocating to the nucleus upon phosphorylation where it engages SMAD-binding element (SBE) motifs to regulate fibrosis, cancer, epithelial-mesenchymal transition, and inflammatory gene programs. Nuclear and cell lysates are loaded into the microplate wells, which are pre-immobilized with Smad3-specific double-stranded oligonucleotide probes. Active Smad3 within the sample binds these probes and is then revealed with an anti-Smad3 antibody, an HRP-conjugated secondary reagent, and a chromogenic substrate solution whose absorbance reflects Smad3 DNA-binding activity. Compatible with human, mouse, and rat samples, the kit is supplied in a microplate format and supports in vitro research into pathway activation, ligand response, and inhibitor screening. Reagent vials should be stored refrigerated; avoid excessive freeze-thaw cycles. For research use only.