Figure 4: TGFβ mediates Activin A-induced EMT and DE formation.

(a) qRT-PCR analysis of TGFβ1 expression levels in un-induced hESCs, or in differentiation media with or without Activin A (Act). The expression level of GAPDH is arbitrary set as 1. Data represent mean±s.d. from three independent biological repeats (**P<0.01 when compared to D0 using Student’s unpaired t-test). (b) Secreted protein levels of TGFβ in conditioned medium at day 3 detected by ELISA. Data represent mean±s.d. from three independent repeats (**P<0.01 when compared to D0 using Student’s unpaired t-test). (c) qRT-PCR analysis for the indicated genes in the absence or presence of Repsox (Rep). Data represent mean±s.d. from three independent repeats (*P<0.05; **P<0.01; ***P<0.001 when compared to D0 using Student’s unpaired t-test). (d) Immunofluorescence staining of Activin A-induced cells with or without Repsox. The right panels are cells treated with TGFβ instead of Activin A. Scale bar, 20 μm.