Fig. 1.

Efficient ablation of Pax7⁺ cells. (A) Tamoxifen (tmx) regimen and harvest scheme. Vertical lines indicate daily intervals. (B) Tibialis anterior (TA) muscle diagram. Horizontal lines indicate the orientation of sections (i.e. cross-sections) used for analysis. (C-J) Fluorescent microscopy of Pax7^+/CE;R26R^+/lacz (C,D,G,H) and Pax7^+/CE;R26R^{eGFP-DTA/lacz} (E,F,I,J) TA muscle cross-sections at 1.5 days after tmx administration (C-F) [referred to as day-0 as cardiotoxin (CTX)-induced injuries are performed at this time (see Fig. 2)] and 6.5 days after tamoxifen administration (G-J) [referred to as day-5 as this represents the 5-day regeneration time point (see Fig. 2)]. Pax7 is shown in white (C,E,G,I) or pseudocolored in magenta with DAPI shown in cyan (D,F,H,J). White arrows indicate satellite cells. Boxed insets show magnified views of the area indicated by a dotted white box. (K) Mean number of satellite cells at day-0 (left) and day-5 (right) per 0.154 mm²; 20 random areas/animal (n=3/genotype). Error bars represent s.d. Scale bar: 50 μm.