Fig. 8.

smo-mutant embryos, lacking slow-twitch fibres, are unresponsive to Urp over expression. (A) An smo-mutant embryo at 48 hpf. (B) An smo-mutant embryo injected with myog::urp2 transgene. Note that there was no effect on the ventrally curved axis. This experiment was performed in two independent biological replicates. In the first batch, five wild-type siblings showed no dorsal curvature and 57 showed dorsal curvature. All 12 smo mutants showed no response. In the second batch, of 105 wild-type siblings all showed dorsal curvature. All 24 smo mutants showed no response. (C) An smo-mutant embryo at 48 hpf, injected with water in the dorsal somite, imaged after 1 h. (D) An smo-mutant embryo, injected with Urp1 in the dorsal somite, imaged after 1 h. Note that there was no effect on the ventrally curved axis. The injection sites are indicated (magenta arrows). Four embryos were injected for each condition. Scale bars: 1 mm.