Fig. 1.

Paxbp1 was indispensable for muscle regeneration. (A–C) The expression of various proteins was examined by Western blot using equal amounts of soluble whole-cell lysates from (A) FISCs and ASCs cultured for 24 and 48 h; (B) MuSCs directly isolated from wild-type mice that were either noninjured or injured for various times as indicated; and (C) FISCs from control (Ctrl) and Paxbp1-iKO mice. (D) Representative images of regenerating TA muscles stained by hematoxylin & eosin at 5, 14, and 30 dpi in Ctrl and Paxbp1-iKO mice. The second and fourth rows are enlarged views from the corresponding images in the first and third rows, respectively. (E) Immunostaining for embryonic MHC (red) and laminin (green) on TA muscle cross-sections at 5 dpi from Ctrl and iKO mice. (F) Quantification of eMHC⁺ myofibers in E (n = 3 mice per group). In E, nuclei were counterstained with DAPI (blue). Data are presented as mean ± SD. (Scale bars, 100 µm [D] and 50 µm [E].)