Figure 2. Klf5 is required for muscle regeneration in vivo.
CTX was injected into the TA muscles of SC-specific Klf5 knockout mice (Pax7CE/+;Klf5flox/flox) and control Pax7+/+;Klf5flox/flox mice. The animals were then sacrificed on day 4 (A), 7 (B–D) or 28 (E–F) after CTX injection. (A) Pax7, Myod1, Myog and Myh3 expression in regenerating TA muscle (on day 4 after CTX injection) was analyzed using qRT-PCR (A). Data represent means ± SEM. n = 3 for each group. **p<0.01. N.S., not significant. (B–F) Sections were stained with H&E or immunostained for eMyHC, laminin and collagen I. Representative images of muscle sections on day 7 (B) or 28 (E) after CTX injection are shown. The eMyHC-positive area 7 days after CTX injection was quantified using Olympus cellSense Digital Imaging software (C). Distributions of myofiber diameters on days 7 (D) and 28 (F) after CTX injection are shown. Representative data from four Klf5 knockout and five control (for day 7) or four mice for each genotype (for day 28) are shown. Scale bars represent 100 µm. ***p<0.001. **p<0.01. N.S., not significant.
Figure 2—figure supplement 1. Tamoxifen treatment does not affect TA muscle morphology.
