GFP expression in the G0 embryos, into which the plasmid was injected without (a, b) and with (c, d) transposase mRNA, at Stage 15 (4 dpf, 72 hpf). Lateral views of embryos. Left side (a, c), views on dark field. Right side (b, d), views through GFP filter. (a, b) No GFP expression was observed in the transposase (−) embryos. (c, d) Mosaic GPF expression was observed along the entire body in the transposase (+) embryos. Scale bar, 1 mm.