Anti-SMAD2 (phospho S465 + S467) + SMAD3 (phospho S423 + S425) Antibody

SMAD2 and SMAD3 serve as the receptor-activated intracellular effectors of the TGF-β signaling cascade, where ligand-induced activation of the type I receptor leads to phosphorylation at the C-terminal SSXS motif. This rabbit polyclonal antibody from Antibodies.com specifically recognizes the doubly phosphorylated forms of SMAD2 at Ser465/Ser467 and SMAD3 at Ser423/Ser425, the receptor-mediated phosphorylation sites that mark pathway activation. The reagent is supplied as 100 µl of unconjugated IgG and is validated for Western blot detection of endogenous phospho-SMAD2 and phospho-SMAD3 in human and mouse samples. This dual-target approach provides a useful internal control when comparing signaling outputs, since both proteins are phosphorylated by the same activated receptor complex and their detection on the same membrane can help normalize TGF-β pathway activity across experimental conditions. Researchers commonly apply such phospho-specific detection in studies of fibrosis, epithelial-mesenchymal transition, tumor progression, and developmental biology, where transient or sustained pathway activation drives distinct biological outcomes.