Fig. 2.

The deletion of Islr delays skeletal muscle regeneration. a A schematic illustration showing the location of loxP in the Islr gene. b Western blot analysis of Islr protein levels in isolated satellite cells of control and Islr cKO mice cultured for 4 d in proliferation medium. c Immunohistochemistry analysis of Islr in Pax7⁺ cells of control and Islr cKO mice at 5 d postinjury using serial sections. Scale bar = 10 μm. d Western blot analysis of Islr protein levels in injured TA muscles of control and Islr cKO mice at 5 d postinjury. e H&E staining of injured and contralateral TA muscles (CTL) in control and Islr cKO mice at 3.5 (N = 3), 5 (N = 4), and 14 (N = 3) d post injury. Scale bar = 100 μm. f Average cross-sectional area (CSA) of regenerating myofibers and g the number of myofibers containing two or more centrally located nuclei per field at 5 d postinjury. N = 3 in each group. h Distribution of myofiber CSAs at 5 d postinjury. N = 3 in each group. Error bars represent the means ± s.d. NS not significant, ^**P < 0.01, ^***P < 0.001; Student’s t test. Control (Ctrl): Myf5-Cre^+/−, Islr^fl/fl; Islr cKO: Myf5-Cre^+/−:Islr^fl/fl