Figure 6. Forced expression of downregulated protein myomaker (MYMK) did not rescue abrogated myotube formation. (A) Quantification of MYMK mRNA levels in skeletal muscle primary cells cultured alone or cocultured with 2G11 or PMS-2G11 cells. Data are expressed as means±SE (n=3); distinct letters (a, b) indicate statistically significant differences (P<0.05). (B) Immunocytochemical analysis of MHC in skeletal muscle primary cells transfected with GFP or MYMK and cultured alone or cocultured with PMS-2G11 cells. Arrowhead: MHC+ myotube. (C) Fusion index of differentiated skeletal muscle primary cells, quantified as the percentage of the number of nuclei in myotubes (>2 myonuclei) relative to the total number of nuclei in a field. Data are expressed as means±SE (n=3); *P<0.05.