Fig. 3

Lmo7, Gli1, alpha-actinin and desmin are concentrated in the nuclear cloud in skeletal muscle fibers. Primary cultures of chick myogenic cells were labeled with antibodies against Lmo7 (B), Gli1 (C–E), alpha-actinin (F) and desmin (G–H), and with the nuclear dye DAPI (D–F). A 72-h chick multinucleated myotube was visualized under phase contrast microscopy (A) and under fluorescence microscopy to show the localization of Lmo7 (green, in B). Arrows in A and B point to Lmo7 distribution near the nuclear surface of a myotube. White open circles (in A and B) mark the region of one nucleus surrounded by Lmo7-positive aggregates. Scale bar in A = 10 μm. Gli-1 (red, in C and E) localizes at the perinuclear region of a 72-h multinucleated myotube (arrow in E). A merged image (with Gli1 and DAPI) is shown in E. Scale bar in E = 5 μm. The intermediate filament desmin and the sarcomeric protein alpha-actinin accumulate at the perinuclear region of mononucleated myoblasts (F and G) and multinucleated myotubes (H). A merged image of sarcomeric alpha-actinin and DAPI is shown in (F). Note the punctate distribution of alpha-actinin (arrows in F) and the continuous distribution of desmin filaments (arrows in G and H) in the juxtanuclear region of cells. Scale bars in F and H = 10 μm, and in G = 5 μm. n = 4 independent experiments.