Figure 8.

Working model for the mechanism by which skMLCK can enhance myogenesis. (A) Previous studies have shown that MEF2C is inhibited by class II HDACs (HDAC CII), synergizes with MRFs, and recruits p300 to promoters (Sartorelli et al, 1997; Lu et al, 2000; Potthoff and Olson, 2007). Here, we show that skMLCK directly phosphorylates MEF2C, leading to p300/PCAF recruitment, increased acetylation of skeletal muscle-specific genes, and enhanced skeletal myogenesis. (B) Comparison of the stages of myogenesis in embryonic stem cells and satellite cells. ML-7 reduced the efficient upregulation of MRFs in the ES-derived premyogenic mesoderm or during the activation of quiescent satellite cells. In agreement with other studies (Palacios et al, 2010), SB inhibited the loss of Pax7, required for myoblast formation and subsequent differentiation.