Figure 3.

Satellite Cell-specific Deletion of Rpt3 Prevents Muscle Regeneration

(A) Time course for tamoxifen (Tmx) and cardiotoxin (CTX) treatment. Con indicates Rpt3^f/f mice and scKO indicates satellite cell-specific Rpt3 knockout mice (Pax7^CreERT2/+; Rpt3^f/f).

(B) Representative images of tibialis anterior (TA) muscles in Con and scKO mice.

(C and D) Change in (C) muscle weight (mg) and (D) muscle weight (mg)/body weight (g). Data represent mean ± SEM (t test: ^∗p < 0.05, ^∗∗p < 0.01 versus Con, n = 5–9 per group).

(E) H&E staining of intact muscles and those injured by CTX injection, analyzed at 3, 7, and 14 days post injury. Scale bar, 50 μm.

(F) Immunostaining of collagen I (red) and DAPI (blue) in TA muscle cryosections from scKO mice 14 days after injury. Scale bar, 100 μm. The y axis shows the mean collagen I fluorescence intensity (ratio). Data represent means ± SEM (t test: ^∗∗∗p < 0.001; n = 5 per group).

(G) Immunostaining of Laminin (red) and DAPI (blue) in TA muscle cryosections from scKO mice 14 days after injury. Scale bar, 100 μm. The y axis shows the mean cross-sectional area (CSA). Data represent means ± SD (t test: ^∗∗p < 0.01; n = 3 per group).

(H) Immunostaining for MYOD (green), Laminin2α, and DAPI (blue) in TA muscle cryosections from scKO mice 3 days after injury. Scale bar, 50 μm. The y axis shows the relative ratio of MYOD-positive areas. Data represent means ± SD (t test: ^∗∗p < 0.01; n = 3 per group).