ZFIN ID: ZDB-PUB-060508-12
Zebrafish endoderm formation is regulated by combinatorial Nodal, FGF and BMP signalling
Poulain, M., Fürthauer, M., Thisse, B., Thisse, C., and Lepage, T.
Date: 2006
Source: Development (Cambridge, England) 133(11): 2189-2200 (Journal)
Registered Authors: Fürthauer, Maximilian, Lepage, Thierry, Poulain, Morgane, Thisse, Bernard, Thisse, Christine
Keywords: Endoderm, Zebrafish, FGF, BMP, MAP kinase, Mesoderm, Casanova, Bon, ERK
MeSH Terms:
  • Activin Receptors, Type I/metabolism
  • Amino Acid Sequence
  • Animals
  • Bone Morphogenetic Proteins/metabolism*
  • Conserved Sequence
  • DNA-Binding Proteins/chemistry
  • DNA-Binding Proteins/metabolism
  • Embryo, Nonmammalian/embryology
  • Embryo, Nonmammalian/metabolism
  • Endoderm/metabolism*
  • Extracellular Signal-Regulated MAP Kinases/metabolism
  • Fibroblast Growth Factors/genetics
  • Fibroblast Growth Factors/metabolism*
  • Gene Expression Regulation, Developmental
  • High Mobility Group Proteins/chemistry
  • High Mobility Group Proteins/metabolism
  • Homeodomain Proteins/genetics
  • Homeodomain Proteins/metabolism
  • Humans
  • Mitogen-Activated Protein Kinases/metabolism
  • Molecular Sequence Data
  • Mutation/genetics
  • Nodal Protein
  • Phenotype
  • Phosphorylation
  • SOX Transcription Factors
  • SOXF Transcription Factors
  • Sequence Alignment
  • Signal Transduction*
  • Transcription Factors/chemistry
  • Transcription Factors/genetics
  • Transcription Factors/metabolism
  • Transforming Growth Factor beta/genetics
  • Transforming Growth Factor beta/metabolism*
  • Zebrafish/embryology*
  • Zebrafish/genetics
  • Zebrafish/metabolism*
  • Zebrafish Proteins/chemistry
  • Zebrafish Proteins/genetics
  • Zebrafish Proteins/metabolism
PubMed: 16672336 Full text @ Development
FIGURES
ABSTRACT
In the zebrafish embryo, the mesoderm and endoderm originate from common precursors and segregate during gastrulation by mechanisms that are largely unknown. Understanding how the signalling pathways that regulate endoderm and mesoderm formation interact is crucial to understanding how the germ layers are established. Here, we have analysed how the FGF and BMP pathways interact with Nodal signalling during the process of endoderm formation. We found that activation of the FGF/ERK pathway disrupts endoderm formation in the embryo and antagonizes the ability of an activated form of Tar/Acvr1b to induce endoderm at the animal pole. By contrast, inhibition of FGF signalling increases the number of endodermal precursors and potentiates the ability of Tar*/Acvr1b to induce endoderm at the animal pole. Using a pharmacological inhibitor of the FGF receptor, we show that reducing FGF signalling partially rescues the deficit of endoderm precursors in bon mutant embryos. Furthermore, we found that overexpression of BMPs compromises endoderm formation, suggesting that formation of endoderm precursors is negatively regulated by BMPs on the ventral side. We show that simultaneous inhibition of the FGF/Ras and BMP pathways results in a dramatic increase in the number of endoderm precursors. Taken together, these data strongly suggest that BMP and FGF-ERK pathways cooperate to restrict the number of endodermal progenitors induced in response to Nodal signalling. Finally, we investigated the molecular basis for the FGF-MAPK-dependent repression of endoderm formation. We found that FGF/ERK signalling causes phosphorylation of Casanova/Sox32, an important regulator of endoderm determination, and provide evidence that this phosphorylation attenuates its ability to induce sox17. These results identify a molecular mechanism whereby FGF attenuates Nodal-induced endodermal transcription factors and highlight a potential mechanism whereby mesoderm and endoderm fates could segregate from each other.
ADDITIONAL INFORMATIONNo data available