Fig. 5. MPM enhances mitochondrial respiration to promote C2C12 myogenic differentiation.

a, b MPM silencing inhibited mitochondrial respiratory activity. c, d MPM overexpression enhanced mitochondrial respiratory activity. For a–d, C2C12 myoblasts were transfected with the indicated plasmids for 48 h before detection for oxygen consumption rate (OCR). The basal and maximal oxygen consumption and ATP production of mitochondria (b, d) were calculated based on the OCR (a, c) detected by Seahorse XFe24 analyzer. e PGC-1α overexpression attenuated the inhibitory effect of siMPM on myogenic differentiation. C2C12 myoblasts were transfected with the indicated plasmids for 12 h, then transfected twice at 12-h intervals with NC or a mixture of siMPM-1 and -2 (siMPM-mix). Twelve hours after the last transfection, the cells were refreshed with differentiation medium and incubated for 48 h, then subjected to qPCR assay for MHC level. Data are presented as mean ± SEM in a–e. *P < 0.05; **P < 0.01; ***P < 0.001; ns, not significant. f Working model of MPM function in myogenic differentiation