Fig. 1 Non-coding conserved elements drive mosaic gfp expression in the midline of transient transgenic zebrafish embryos. (A) Zebrafish embryo injected with control gfp-reporter construct, containing a minimal - 0.563 kilobase (kb) zebrafish shh promoter without cis-regulatory motif. (B to H) Embryos were injected with the gfp-reporter 0.563shh:GFP fused to the non-coding conserved sequences arx A7 (B), id1 A8 (C), nkx2.2b A21 (D), sox9a E1 (E), ctgf up1 (F), shh ar-C (G) and shh ar-A (H), respectively. arx A7 (B) and nkx2.2b A21 (D) drove expression in the floor plate while id1 A8 (C), sox9a E1 (E), ctgf up1 (F), shh ar-C (G) and shh ar-A (H) mediated gfp expression in the notochord at 24 h post-fertilization (hpf). Embryos are oriented anterior to the left and dorsal up. Scale bar = 250 μm.
Reprinted from Developmental Biology, 318(2), Rastegar, S., Hess, I., Dickmeis, T., Nicod, J.C., Ertzer, R., Hadzhiev, Y., Thies, W.G., Scherer, G., and Strähle, U., The words of the regulatory code are arranged in a variable manner in highly conserved enhancers, 366-377, Copyright (2008) with permission from Elsevier. Full text @ Dev. Biol.