Figure 4. Itm2a is expressed in adult skeletal muscles.

A–D, Immunohistochemistry on isolated single fibers from the EDL muscle of adult Itm2a^XcdKO/Y mice immediately after isolation (T0) (A, B), or after 48 h, (T48) (C) or 72 h (T72) (D) culture, using Dapi staining (blue) and antibodies recognizing Pax7 (red, A, green B), β-Gal (green, A, C, D, red, B), MyoD (red, C) and Myogenin (red, D). Arrowheads point to Pax7-positive satellite cells (A,B). E, X-Gal staining for β-Gal on isolated single EDL fibers from adult Itm2a^XcdKO/Y mice at T0 showing examples where the myonuclei are positive or negative. Dapi is shown in blue. X-Gal positive staining quenches DAPI. F, Immunohistochemistry on transverse sections of EDL muscle isolated from adult Itm2a^XcdKO/Y mice with Dapi staining (blue), and antibodies recognizing Laminin (green) (left) or slow myosin heavy chain (red) and β-Gal (blue) (right) as indicated. G, Immunohistochemistry experiments on isolated single fibers from adult Itm2a^XcdKO/Y and Itm2a^XKO/Y mice after 48 h culture (T48) with Dapi (blue) and an antibody recognizing MyoD (red). H, Eosin-hematoxylin staining on transverse sections of the EDL muscle isolated from adult control Itm2aXcdKO/Y (top) and Itm2aXKO/Y (bottom) mice, 10 days after cardiotoxin injury (CTX) (right) or PBS injection (control) (left). Dapi staining (blue) marks nuclei. In G and H the mice were crossed with the PGK-Cre line to delete the floxed Itma2 allele.