Skeletal Muscle Cell Induction from Pluripotent Stem Cells

Figure 3

Schematic model for chromatin status of myoblast versus fibroblast-derived iPSCs for myogenic induction. In myoblasts, MyoD binds to the two MyoD enhancers (core and DRR) and promoter (PRR), and histone marks show the open chromatin state characteristic. During iPSC reprogramming via expression of Oct4, Sox3, Klf4, and cMyc, exogenous Oct4 binds to both MyoD enhancers which may lead to the bivalent state characteristic of pluripotent stem cells. In fibroblast, both MyoD enhancers and promoter show the closed chromatin state characteristic. During iPSC reprogramming, exogenous Oct4 binds to both MyoD enhancers which may lead to the bivalent state characteristic of pluripotent stem cells. However, myoblast-derived iPSCs may maintain the more open bivalent state characteristic, and thus, myogenic conversion efficiency is increased upon induction.