Fig. 4

Effects of MAPK inhibition on cardiac-specific transcription factors expression. Quantitative analyses in RT-PCR for three transcription factors Csx/Nkx2.5 (a), GATA4 (b), and MEF2C (c), were performed on the differentiation day 14 with or without MAP kinase inhibitors (control): PD98059 (10 μM), SP600125 (10 μM) and SB203580 (10 μM). Each expression level was normalized to the ratio in control cells on the differentiation day 14. Representative PCR products are shown in inset (upper) with the reference gene GAPDH (below). Each mRNA product was normalized to that of GAPDH. Data were calculated and normalized to those in the control condition (without MAP kinase inhibitor). *p < 0.05 vs. control, **p < 0.01 vs. control