(C) Immunoblot of phosphorylated Smad2 (P-Smad2), total Smad2 and β-actin upon ActivinB or TGFβ stimulation for 1 hour. lower panels represent the relative quantification of P-Smad2 normalized to β-actin. The p-values were determined by unpaired t-test. *p < 0.05, **p < 0.01, ***p < 0.001. Bars represent the mean ± SD. Number of replicates is n≥3. 