Larger Image Fig. 2. Regulation of hhex expression by Nodal and Wnt/β-catenin signaling. (A) Nodal and Wnt signaling are required for hhex expression. In situ hybridization of hhex and gfp in bisected −6.0Kb:hhex:gfp transgenic gastrulae injected with β-catenin-MO (20 ng), ∆Ntcf3 RNA (500 pg), stabilized pt-β-catenin RNA (250 pg), xnr1 RNA (50 pg), and/or cer-s RNA (750 pg). The number of embryos exhibiting the depicted phenotype is indicated. Transgenic F1 males are heterozygous, and approximately 50% of the embryos are expected to express gfp. (B) The schematic indicates the cells injected with the hhex:luc reporter (300 pg) plus pRL-TK:Renilla (25 pg). Co-injection with xnr1 RNA (1–500 pg) and/or β-catenin RNA (20–200 pg) resulted in a dose-dependent activation the hhex:luc reporter in the ectoderm. The histogram shows the average normalized luciferase activity and standard deviation from a single injection experiment performed in biological triplicate. A representative example of 4 independent experiments is shown. (C) hhex is a direct Nodal-target and an indirect Wnt-target. Blastula stage animal cap tissue was cultured either untreated, with Activin or with BIO. Some explants were incubated in CHX for 30 min prior to and during culture to block protein synthesis. At stage 11, the animal caps were assayed by in situ for hhex, gfp, cerb, and xnr3. This experiment was repeated 3 times, with identical results and a total of 12–15 caps per treatment. A representative example is shown. Image published in: Rankin SA et al. (2011) Copyright © 2011. Image reproduced with permission of the Publisher, Elsevier B. V. Gene Synonyms Species Stage(s) Tissue hhex.L hex, tHex, XHex X. laevis Throughout NF stage 10.5 endoderm endomesoderm cer1.S cer, cer-1, Cerberus, dand4, LOC108713989, tCerberus, xcer, xcer-1, xcer1 X. laevis Throughout NF stage 10.5 endoderm endomesoderm involuting marginal zone nodal3.1.L nr3, Xnr-3, Xnr3 X. laevis Throughout NF stage 10.5 endoderm anterior Image source: Published Experiment + Assay Source Phenotypes and Disease Xla Wt + cer1del + NF11 (in situ hybridization) fig.2.a Expression Phenotype decreased amount hhex.L expression in dorsal endoderm Xla Wt + cer1del + ctnnb1tm1 + NF11 (in situ hybridization) fig.2.a Expression Phenotype decreased amount hhex.L expression in dorsal endoderm Xla Wt + ctnnb1 MO + NF11 (in situ hybridization) fig.2.a Expression Phenotype decreased amount hhex.L expression in dorsal endoderm Xla Wt + nodal1 + ctnnb1 MO + NF11 (in situ hybridization) fig.2.a Expression Phenotype mislocalised hhex.L expression in endoderm increased amount hhex.L expression in endoderm Xla Wt + nodal1 + dntcf3 + NF11 (in situ hybridization) fig.2.a Expression Phenotype mislocalised hhex.L expression in endoderm increased amount hhex.L expression in endoderm Xla Wt + dntcf3 + NF11 (in situ hybridization) fig.2.a Expression Phenotype decreased amount hhex.L expression in dorsal endoderm Xla Wt + Activin + animal cap explant + NF11 (in situ hybridization) fig.2.c Expression Phenotype increased amount cer1.L expression in animal cap increased amount hhex.L expression in animal cap decreased amount nodal3.1.L expression in animal cap Xla Wt + Activin + CHX + animal cap explant + NF11 (in situ hybridization) fig.2.c Expression Phenotype decreased amount cer1.L expression in animal cap increased amount hhex.L expression in animal cap decreased amount nodal3.1.L expression in animal cap Xla Wt + BIO + animal cap explant + NF11 (in situ hybridization) fig.2.c Expression Phenotype decreased amount cer1.L expression in animal cap increased amount hhex.L expression in animal cap increased amount nodal3.1.L expression in animal cap Xla Wt + BIO + CHX + animal cap explant + NF11 (in situ hybridization) fig.2.c Expression Phenotype decreased amount cer1.L expression in animal cap decreased amount hhex.L expression in animal cap increased amount nodal3.1.L expression in animal cap Xla Wt + CHX + animal cap explant + NF11 (in situ hybridization) fig.2.c Expression Phenotype decreased amount cer1.L expression in animal cap decreased amount hhex.L expression in animal cap decreased amount nodal3.1.L expression in animal cap Permanent Image Page Printer Friendly View XB-IMG-48869