METTL3-Mediated m⁶A Methylation Regulates Muscle Stem Cells and Muscle Regeneration by Notch Signaling Pathway

Figure 1

METTL3 is required for muscle regeneration in vivo. (a) Schematic outline of CTX injection in tamoxifen-treated CTL and cKO littermates. (b–d) Immunofluorescence staining and Western blot analysis of TA muscle after injection for 5 days for METTL3. (e) Hematoxylin and eosin (H&E) staining of TA muscles of METTL3 cKO mice and control littermates 2, 5, and 8 days after CTX injection. (f) Number of muscle fibers. (g) Area of regenerating centronuclear fibers. (h) Masson’s Trichrome staining of TA muscles of METTL3 cKO and control littermates. (i) Western blot analysis of Pax7, myosin, myogenin, and METTL3 protein levels in control TA muscle at day 0, day 2, day 5, and day 8. (j) Immunofluorescence staining of TA muscles from METTL3 cKO and control mice detected by myogenin. (k) Quantifications of myogenin staining. (l) Western blot analysis of myogenin. (m) Immunohistochemical staining of myosin. (n) Quantifications of myosin staining. (o) Western blot analysis of myosin. . ; ; ; . CTX: cardiotoxin; TAM: tamoxifen; TA: tibialis anterior; CTL: control; cKO: METTL3 conditional knockout.

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