Fig. 4

Myog⁺ cells can undergo cell division. a MuSCs were isolated based on GFP fluorescence from Tg:Pax7-nGFP^Tg/+; Myog^ntdTom/+ mice. Cells were plated for 3 days before initiating live imaging. Black arrowheads point to a tdTOM⁺ cell dividing and its daughter cells. Images were acquired every 9 min. Scale bar, 25 μm. b Representative tracking output from experiment in a. c The left bar graph shows the percentage of tdTOM⁻ and tdTOM⁺ cells that have undergone at least one cell division. The right bar graph indicates the average number of divisions that tdTOM⁻ and tdTOM⁺ underwent during the tracking period (n = 4, 100 cells tracked in total). Data represent mean ± s.d. Two-tailed unpaired Student’s t test; **p value = 0.005 to 0.01. d Recombination of Pax7-expressing cells in Pax7^CreERT2; R26^YFP; Myog^ntdTom reporter mice was induced 1 day before injury of the upper hindlimb muscle. Images were acquired by intravital imaging at 2 timepoints during muscle regeneration (1 mouse/timepoint). White arrows indicate double-positive YFP and tdTOM cells. Scale bar, 100 μm