Fig. 4: SAM loss in SCs leads to cell-autonomous defects in proliferation.

a Top: the experimental scheme for in vivo EdU assay in WT and KO or b Ctrl and iKO mice. Bottom: The percentage of EdU+ SCs was quantified. c Top: the experimental scheme for in vitro EdU assay in 48 h-cultured SC isolated from WT and KO mice. Bottom: The percentage of EdU+ cells was quantified. d The above cultured cells were stained for Pax7 and MyoD. The percentage of double-positive cells was quantified. e and f The above assays were performed in SCs isolated from Ctrl and iKO mice. g EdU assay was performed on single myofibers isolated from WT and KO mice. The percentage of EdU+ SCs was quantified. h EdU assay in ASC transfected with a Vector or SAM expressing plasmid. The percentage of EdU+ SCs was quantified. The center line is represented as mean. i EdU assay in 30 h-cultured SC isolated from WT and KO mice. The percentage of EdU+ SCs was quantified. j Pax7 and MyoD staining in 20h-cultured SCs isolated from WT and KO mice. The percentage of double-positive cells was quantified. k MyoD and MyoG staining in 3 days-cultured SCs isolated from WT and KO mice. Quantification of the double-positive cells was performed. l MF20 staining in 4 days-cultured SCs isolated from WT and KO mice. The fusion index of myotubes (≥2 nuclei)/total MF20+ cells) was quantified. DM differentiation medium. The data are presented as mean ± SD in a–g and i–l. The p values by two-tailed unpaired t test are indicated in a, d, h, and l and by two-tailed paired t test are indicated in b, c, e, f, g, i, j, and k. The total number of mice used in a–g, i–k and biologically independent samples in h and l are indicated. Scale bars: 100 µm a–l. Source data are provided as a Source Data file.