Fig. 4
Fast muscle-specific expression of human mysterin restores the fast muscle malformation in morphants.
(a) Ectopic expression of human mysterin restores the morphology of fast muscle in mysterin morphant larvae. Labeling of F-actin shows the formation of robust muscle fibers upon ectopic expression of mysterin in fast muscle, but not in the control. Expression of RFP driven by the UAS promoter shows that these larvae carry the GAL4FF-expressing transgene in fast muscle. (b) EM observation of restored fast muscle in the trunk. The lower panels show magnified images. (c) Projection of primary motoneurons in somites. Projection of motoneurons is impaired in mysterin-α morphants and restored by fast muscle-specific expression of human mysterin (white arrows). (d) Effect of suppression of mysterin-α and fast muscle-specific expression of human mysterin on vascular formation. Human mysterin tagged with a 3×FLAG epitope (WT-3×FLAG) is expressed in transgenic zebrafish that express GFP in vascular endothelial cells. Green (GFP) and magenta (F-actin) show trunk vessels and fast muscle, respectively.