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Fig. 3 Zebrafish eaf1 and eaf2 induce anterior neuroectoderm by acting as transcriptional repressors. (A) (a) mRNAs used for injection encode full-length or the N- or C-terminus of Eaf1 or Eaf2 fused with the transcriptional activator VP16 or the engrailed transcriptional repressor domain (EnR). Numbers refer to amino acid residues in Eaf1 and Eaf2. (b) Embryos injected with GFP mRNA at 26 hpf exhibit normal morphology. (c-f) Embryos injected with eaf1-N-EnR mRNA display similar morphology to embryos injected with full-length eaf1 mRNA. (g-j) Embryos injected with eaf1-N-VP16 mRNA display phenotypes with obvious anterior neuroectoderm truncation, similar to Eaf morphants. (B) eaf1 and eaf2 act as anterior neuroectoderm inducers by repressing transcription. six3b (a-e) and opl (f-j) displayed expanded expression in embryos injected with eaf1/2-EnR or eaf1/2-N-EnR mRNA. (k-o) egr2b expression was reduced in embryos injected with eaf1/2-EnR or eaf1/2-N-EnR mRNA. Ba-o, dorsal views, anterior to the left. All mRNA injections were at 50 pg/embryo.