Xenbase Image ID: 156716

Figure 2. XSox17β Can Inhibit Wnt Signaling Downstream of β-catenin (A) The left panels show representative tail bud stage embryos with a second axis induced by the injection of one ventral blastomere at the 4 cell stage with mRNA encoding dnBMPR (250 pg), bVg1 (100 pg), Xwnt8 (5 pg). Panels on the right show representative embryos similarly injected with the addition of XSox17β (500 pg). XSox17β only inhibits the second axis induced by Xwnt8 (lower right). (B) Summary of second axis assays from three to five separate experiments. Injection of mRNA encoding dnBMPR (250 pg), bVg1 (100 pg), Xwnt8 (5 pg), β-catenin (250 pg), or Siamois (10 pg), resulting in a high frequency of embryos with second axes (gray bars). Embryos similarly injected with the same RNAs + XSox17β mRNA (500 pg) were scored for percent second axis (black bars). (C) Ventralization assay. RNA encoding XSox17β (1 ng) or XSox17β (1 ng) + Xwnt8 (10 pg); XSox17β (1 ng) + β-catenin (250 pg); XSox17β (1 ng) + XTcf-3 (2 ng); XSox17β (1 ng) + Siamois (20 pg) was injected into both dorsal blastomeres at the 4 cell stage (black bars). Control injections (gray bars) without XSox17β were Xwnt8 (10 pg), β-catenin (250 pg), XTcf3 (2 ng), ΔN-XTcf3 (500 pg), ΔN-XTcf3 (500 pg) + XTcf3 (2 ng), and Siamois (20 pg). The dorsal development of the resulting embryos were scored by a dorsal anterior index (DAI; Kao and Elinson 1988). A score of 5 indicates normal development, and a score of 0 indicates severely ventralized embryos. Only Siamois rescued the ventralized phenotype caused by dorsal XSox17β injection. (D) XSox17β operates downstream of β-catenin but upstream from Siamois. Image published in: Zorn AM et al. (1999) Copyright © 1999. Image reproduced with permission of the Publisher, Elsevier B. V. Experiment + Assay Source Phenotypes and Disease Xla Wt + sox17b.2 + tailbud stage (morphology) fig.2.a Anatomical Phenotype increased size of the endoderm Xla Wt + sox17b.2 + cagdf1 + tailbud stage (morphology) fig.2.a,b Anatomical Phenotype obsolete duplicated anterior-posterior axis Xla Wt + sox17b.2 + dnbmpr1a + tailbud stage (morphology) fig.2.a,b Anatomical Phenotype obsolete duplicated anterior-posterior axis Xla Wt + wnt8a + tailbud stage (morphology) fig.2.a,b Anatomical Phenotype obsolete duplicated anterior-posterior axis Xla Wt + cagdf1 + tailbud stage (morphology) fig.2.a,b Anatomical Phenotype obsolete duplicated anterior-posterior axis Xla Wt + dnbmpr1a + tailbud stage (morphology) fig.2.a,b Anatomical Phenotype obsolete duplicated anterior-posterior axis Xla Wt + ctnnb1 + tailbud stage (morphology) fig.2.b Anatomical Phenotype obsolete duplicated anterior-posterior axis Xla Wt + sia1 + tailbud stage (morphology) fig.2.b Anatomical Phenotype obsolete duplicated anterior-posterior axis Xla Wt + sia1 + sox17b.2 + tailbud stage (morphology) fig.2.b Anatomical Phenotype obsolete duplicated anterior-posterior axis Xla Wt + ctnnb1 + sox17b.2 + tailbud stage (morphology) fig.2.c Anatomical Phenotype abnormally ventralized embryo Xla Wt + sia1 + tailbud stage (morphology) fig.2.c Anatomical Phenotype abnormally dorsalized embryo Xla Wt + sox17b.2 + tailbud stage (morphology) fig.2.c Anatomical Phenotype abnormally ventralized embryo Xla Wt + sox17b.2 + tcf3 + tailbud stage (morphology) fig.2.c Anatomical Phenotype abnormally ventralized embryo Xla Wt + sox17b.2 + wnt8a + tailbud stage (morphology) fig.2.c Anatomical Phenotype abnormally ventralized embryo Xla Wt + tcf3 + tailbud stage (morphology) fig.2.c Anatomical Phenotype abnormally ventralized embryo Xla Wt + dntcf3 + tailbud stage (morphology) fig.2.c Anatomical Phenotype abnormally dorsalized embryo Larger Image Printer Friendly View

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