Fig. 4

Transdifferentiation of pMYOD1-PEFs into myotubes using signaling molecules. a Experimental design for the transdifferentiation of pMYOD1-PEFs into myocytes. The pMYOD1-PEFs were induced toward the myogenic program in the ‘induction’ step, and the induced cells were promoted for myogenic reprogramming in the ‘differentiation’ step. In the differentiation stage, one group was treated with DOX, and the other was not. HS: horse serum, Cont.: Control, FSCHF: FGF2, SB431542, CHIR99021, and forskolin. b Cell images under culture conditions with or without DOX. Scale bar = 200 μm. c qPCR results to confirm the expression patterns of muscle-associated genes (Exo-MYOD1, Endo-MYOD1, MYF5, MYOG, and MHC) in pMYOD1-PEFs. The Cont. group contained pMYOD1-PEFs cultured in basal media. The amount of gene expression in the Cont. group is described as 1 compared to the other groups. Significant differences are represented by different letters, n = 3. d Immunofluorescence images for MHC of pMYOD1-PEFs. The arrows marked a sarcomere-like structure. Scale bar = 100 μm