FGF10 Cardiac Differentiation Figure 3. The FGF-10 response is mediated via FGF receptors. A, RT-PCR results showing gene expression of all 7 isoforms of FGF receptors (FGFRs) during embryonic stem cell cardiomyocyte differentiation (n = 3). B-C, Photomicrographs of embryonic bodies (EBs) stained for FGFR-1 (B) and FGFR-2 (C) at the indicated days. Control, without first antibody. D, Cardiomyocyte differentiation in the presence of the specific small molecule inhibitor of FGFR, PD173074, alone and along with FGF-10. (n = 3). E, Cardiomyocyte differentiation in response to FGF-10 and PD173074 at the indicted times in hanging drop culture. F, RT-PCR data for the expression of cardiomyocyte-specific genes following treatment with FGF-10 or FGFR inhibitor. Control, GAPDH. G, Cardiomyocyte differentiation in the treatment of FGFR-1, FGFR-2 short hairpin RNA (shRNA, n = 3). Control, cells treated with a scramble shRNA. *p,0.05, ***p,0.001. doi:10.1371/journal.pone.0014414.g003 Figure 4. FGF-10 also augments cardiomyocyte differentiation from induced pluripotent stem cells. A, The induced pluripotent stem (iPS) cell line (Nanog promoter-driven EGFP) used in the present study. B–D, Results of cardiomyocyte differentiation from iPS cells in the treatment of FGF-10 (B), FGF-10 neutralizing antibody (C) or FGFR inhibitor PD173074 (D). Control, no treatment. *p,0.05, **p,0.01, ***p,0.001. doi:10.1371/journal.pone.0014414.g004 PLoS ONE | www.plosone.org 7 December 2010 | Volume 5 | Issue 12 | e14414