Fig. 5

Syndecan-3 regulates myoblast homeostasis and migration. a Wild type (WT, top panels) and Sdc3 ^−/− (S3−/−, bottom panels) myofibers cultured in suspension for 4 days, fixed, and immunostained to detect Sdc4 (white), Pax7 (red), Myf5 (green), and nuclei (blue). Arrows indicate a satellite cell doublet on a Sdc3 ^−/− myofiber where one cell is Myf5 + Pax7+ and the other cell is Myf5 + Pax7−. b, c Quantification of Myf5 + Pax7− cells (b) and Myf5 + Pax7+ cells (c) as in a. d Muscle cross sections identifying Myf5+ cells (green) in Sdc3 ^−/− (S3−/−) and wild type (WT) muscles 3 months post-injury. Arrows are interstitial cells; arrowheads are sublaminar cells. e, f Quantification of sublaminar (e) and interstitial (f) Myf5+ cells (normalized to area) in Sdc3 ^−/− (S3−/−) and wild type (WT) muscles 3 months post-injury. g Quantification of the numbers of Ki67+ cells (normalized to area) in wild type (WT) and Sdc3 ^−/− (S3−/−) muscles 3 months post-injury. h More myoblasts migrate away from Sdc3 ^−/− (S3−/−) myofibers transferred to gelatin-coated coverslips after 2.5 days culture in suspension than from wild type (WT) myofibers. i Quantification of adherent myoblasts 4 h after myofiber transfer as in g. Scale bars are 100 μm in a, 50 μm in e, and 20 μm in f. Error bars are S.E.M. and ** = p < 0.01; * = p < 0.05