Fig. 2.

SC-specific Loss of Slug Impairs Muscle Regeneration. a Slug expression in different muscle resident cells. Left, representative flow cytometric gating of SCs (CD31⁻CD45⁻Scal1⁻Vcam I⁺), pan-lymphocytes (LCs, CD45⁺), epithelial cells (ECs, CD31⁺), and fibro-adipogenic progenitors (FAPs, CD31⁻CD45⁻Scal1⁺) from freshly prepared skeletal muscle cells. Right, qPCR analysis of Slug expression. *p < 0.05, **p < 0.01, ***p < 0.001 by student’s t-test. b Quantification of Slug expression in undifferentiated and differentiated SCs. Left, representative images of SCs and myotubes. Scale bar, 100 µm. Right, qPCR analysis of Slug expression. *p < 0.05, ***p < 0.001 by student’s t-test. QSC, quiescent satellite cell; ASC, activated satellite cells upon culture in growth medium for 3 days; MT, myotube. c Gene targeting strategy for generation of SC-specific Slug knockout mice. d Diagram of Slug-specific primer design for genotyping PCR. M. DNA marker; Ng negative control for PCR. e Comparison of adult Slug^fl/flPax7^Cre/+ (Slug^cKO) and Slug^fl/+Pax7^Cre/+ (Ctrl). f Immunofluorescence staining of Slug in SCs of Slug^cKO and Ctrl mice (n = 3 mice). Scale bar, 100 µm. g Frequency of SCs in Slug^cKO and Ctrl mice. Similar results were seen from three independent flow cytometric analyses. h Yield of SCs per mg of muscle from Ctrl and Slug^cKO mice (n = 3 mice for each genotype). *p < 0.05 by student’s t-test. i H&E staining of intact and injured TA muscles in Slug^cKO and Ctrl mice (n = 5 mice per group). For single injury, TA muscles were harvested at day 10 after BaCl₂ injection. For consecutive injury, mice with primary injury were recovered for 1 month followed by a second BaCl₂ injection at the same sites. TA muscles were harvested 10 days after each injury. Scale bar, 100 μm. The experiment was repeated independently for three times with similar results. j Quantification of the myofiber CSA (µm²) shown in i. *p < 0.05 by student’s t-test (n.s., not significant). Data are shown as mean ± SEM of three independent replicates. Also see Supplementary Fig. 2 and 3. Source data are provided as a Source Data file