Fig. 5. TGF-β induces Smad2 Phosphorylation, ARE Induction, and Trophoblast Differentiation Diagrammatic representation of the TGF-β signaling pathway in SM10 growth inhibition and trophoblast differentiation. The ligand, TGF-β, binds to cognate receptors and triggers activation via the TGF-β Type I receptor (ALK-5) to induce the phosphorylation of Smad2. Phospho-Smad2, via classically presumptive Smad 4 binding, triggers the transactivation of ARE response elements in target genes that inhibit cell growth and promote labyrinthine trophoblast differentiation. Smad 7 acts as a classical negative feedback inhibitor for the TGF-β signaling pathway.
© 2018 International Journal of Stem Cells