Fig. 5.

sFRP-1 and Dkk1 antagonize Wnt signaling during final phase of ANE restriction. A qPCR measurements showing the temporal expression of dkk1 (a) and sfrp-1 (b) transcripts per embryo from egg to mesenchyme blastula stage of development. The inset in b shows the number of sfrp-1 transcripts per embryo in fertilized eggs and 60-cell embryos. B Comparing foxq2 expression between Dkk1 morphants (Bb, Be) and sFRP-1 morphants (Bc, Bf) during early and late stages of the ANE restriction. C Beginning at blastula stages, sfrp-1 is downregulated in embryos in the absence of functional Fzl5/8 signaling (e–h). D A model diagram, showing that both zygotic sfrp-1 and dkk1 are activated by Fzl5/8 signaling in the ANE and that they work together in a negative feedback loop to antagonize Wnt1/Wnt8–Fzl5/8 signaling in the ANE territory. The model is based on the data presented in this and the preceding figures, as well as data from [20]. FE, fertilized egg; EB, early blastula; B, blastula; MB, mesenchyme blastula. MO, morpholino. Scale bar = 20 μm