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Fig. 2. Dmrt5 temporal and spatial expression pattern. (A) Temporal expression of Dmrt5 by RT-PCR. RNA was extracted from embryos at the indicated stages. Histone H4 was used as a loading control. (B)Z) Spatial expression pattern of Dmrt5 compared to that of Dmrt4 analysed by whole-mount in situ hybridization. Unless indicated, all embryos are shown in anterior views. Nieuwkoopaber stages are indicated. (B) Initial expression of Dmrt5 is observed at stage12.5 in a horse-shoe shaped area in the anterior region of the neurectoderm. (C) Embryo at the stage as in (A) double stained with NBT-BCIP for Dmrt5 and Nkx2.1 showing that Dmrt5 and Nkx2.1 do not overlap. (D)G) At stage 135, both Dmrt5 and Dmrt4 genes are detected bilateraly at the anterior neural plate border, the Dmrt5 staining region being broader and extending less medially than the Dmrt4 stained area. Weak Dmrt5 expression is also detected at stage 13 in a stripe bordering the posterior side of the initial horse-shoe shaped stained zone (arrowhead). (H) Stage 15 embryo double stained with Dlx6 (dark blue) and Dmrt5 (light blue) showing that Dmrt5 is expressed in a subdomain of the preplacodal ectoderm and that its expression extends to the adjacent neural plate (arrowhead). (I)L) Single (I) and (J) and double (K) and (L) in situ hybridization showing that at stage 17, Dmrt5, but not Dmrt4, is coexpressed with BF-1 in the developping dorsal telencephalon. Note also that Dmrt5 staining is detected anterior to the domain of expression of the neural crest Slug marker. Arrowheads indicate posterior and anterior boundaries of Dmrt5 and Slug, respectively. (M) and (Z) Relationship between the Dmrt5 and Dmrt4 genes at stages 228, as revealed by single (M)Q), (W)Z) and double in situ hybridization (O). (P), (Q), (X) and (Z) lateral and (W) dorsal views, anterior to the right. A high magnification view of the anterior head fold of a Dmrt5 and Dmrt4 double stained embryo is shown in panel O, with Dmrt5 in light blue and Dmrt4 in dark blue. (R)T) Transverse sections of an embryo through the olfactory epithelium and dorsal telencephalon (R), the anterior (S) or posterior (T) diencephalon. (U) and (V) Horizontal sections though the dorsal telencephalon and diencephalon (U) or through the olfactory placodes and dorsal telencephalon (V). (Y) Sagittal section. Note Dmrt5 strong expression in the dorsal telencephalon, olfactory placodes and diencephalon and weak expression in the prospective lens ectoderm and in the mesenchyme surrounding the eyes. Abbreviations: dt, dorsal telencephalon; hm, head mesenchyme; le, lens ectoderm; di, diencephalon; op, olfactory placodes; ppe, preplacodal ectoderm. |
