Fig. 3

Myomaker overexpression is sufficient to drive ectopic fusion in both fast-twitch and slow-twitch muscle cells. A: A 36 h.p.f. embryo with a Myomaker-expressing (as reported by anti-GFP staining) fast-twitch muscle cell displaying hyperfusion (arrow). Fast-twitch muscle cells are labeled with F310 staining, and nuclei and cell membranes are labeled with DAPI and anti-β-catenin staining respectively. Scale bar=20 µm. B: A small percentage of Myomaker-expressing slow-twitch muscle cells can fuse. Top panel shows 3 mononucleated Myomaker-expressing slow-twitch cells (indicated by arrows), while bottom panel shows a binucleated Myomaker-expressing slow-twitch cell (indicated by triangles). The embryos are 21 h.p.f. and stained with anti-GFP (to report Myomaker expression) and F59 antibody (to detect slow-twitch muscle cells). Nuclei and cell membranes are labeled with DAPI and anti-β-catenin staining respectively. Scale bar=20 µm.