Fig. S4

Influence of Hedgehog (Hh) signaling pathway on the MYH_M2528-1 promoter. Hh signaling was inhibited by cyclopamine treatment. Fertilized eggs of Tg:MYH_M2528-1:EGFP were transferred into 2–10 µg mL¹ cyclopamine solution. Control embryos were developed without cyclopamine. (A–F) Morphology and EGFP expression of control (A–C) and 10 µg mL¹ cyclopamine-treated (D–F) transgenic line. (A,D) Ventral views of head of zebrafish larvae at 3 dpf. Inhibition of Hh signaling resulted in a fused-eye phenotype (D). EGFP expression in larvae at 2 dpf (B,E) and 3 dpf (C,F). Cyclopamine-treated larvae displayed a curled body phenotype resulting from Hh signal inhibition but maintained normal EGFP expression in myotomal muscle fibers. (G) The rate of zebrafish embryos expressing EGFP in the larvae at 3 dpf with and without cyclopamine treatment. (H–K) Transverse section of myotomal region of 10 µg mL¹ cyclopamine-treated larvae of Tg:MYH_M2528-1:EGFP at 3 dpf. (H) Primary slow muscle fibers disappeared and secondary slow muscle fiber was stained with F59 antibody. I, merged view showing reacted with F59 and EGFP antibodies. EGFP expressing slow muscle fibers are located at the dorsal extreme region. (J,K) The magnified view of boxed areas of panels H and I. Arrowheads in panels H–K indicate EGFP expressing slow muscle fibers. Scale bars: 100 µm.