Fig. 1.

Spatiotemporal expression of the wnt16 ligand during early anterior-posterior specification and patterning. (A) Diagram showing a model for the areas of Wnt/β-catenin, Fzl5/8-JNK and Fzl1/2/7 signaling during ANE early AP patterning, consistent with previous data (Khadka et al., 2018; Range, 2018; Range and Wei, 2017; and Range et al., 2013). (B) Whole-mount in situ hybridization analysis of wnt16 expression during ANE restriction. (Ba,b) Expression of wnt16 mRNA transcripts was first detected and they were broadly expressed throughout zygotes and 32-cell-stage embryos. (Bd-j) Between the 120-cell stage and late gastrula (30 hpf), wnt16 expression was progressively downregulated from anterior and equatorial ectoderm cells, resulting in a localized expression in the posterior endoderm and mesoderm region of the embryo. (C) qPCR measurements showing the temporal expression of wnt16 transcripts from three different batches of embryos from egg to mesenchyme blastula stages (24 hpf). The number of wnt16 transcripts per embryo (y axis) is based on the Ct value of z12 transcripts. The absolute concentrations of z12 transcripts are known at each stage (Wang et al., 1995). Scale bars: 20 µm. VV, vegetal view.