Fig. 8

Fig. 8 Zebrafish Zic2 patterns the ventral forebrain primordium. Embryos stained by ISH for dlx2a, nkx2.2a, and ptch2 at 24 hpf and pitx2a at 3 dpf. (A) Dlx2a marks the telencephalon, prethalamus and hypothalamus in the developing forebrain of control morphants (42/44, 3 exp.). (B) Zic2b knockdown reduces dlx2a staining in the prethalamus (18/35, 3 exp., see arrowhead). (C) Zic2a knockdown reduces dlx2a in the prethalamus and hypothalamus, as previously described (see Sanek and Grinblat, 2008; 39/43, 3 exp.). (D) Double zic knockdown causes patterning defects similar to single Zic2a knockdown (46/46, 3 exp.). (E,F) Zic2aYFP induction at 10 hpf strongly reduces dlx2a expression in the telencephalon (arrowhead in F) and hypothalamus (61/92, 4 exp.). (G,H) Ptch2 expression is ablated in the hindbrain and spinal cord and reduced in the medial diencephalon of Zic2aYFP-expressing embryos, but maintained in the ZLI (49/57, 2 exp., see arrows in H). (I,J) Zic2aYFP induction between 10 and 11 hpf ablates nkx2.2a expression in the hindbrain (35/35 embryos, 2 exp., arrows in J). (K,L) The stomodeum of zic2a morphants is decreased in size (55/56, 4 exp.). (A–J) are lateral views, (K, L) are ventral views, anterior to the left. Abbreviations: zli—zona limitans intrathalamica.