BMP signaling in the epiblast is required for proper recruitment of the prospective paraxial mesoderm and development of the somites.
Bmpr1a encodes the BMP type IA receptor for bone morphogenetic proteins (BMPs), including 2 and 4. Here, we use mosaic inactivation of Bmpr1a in the epiblast of the mouse embryo (Bmpr-MORE embryos) to assess functions of this gene in mesoderm development. Unlike Bmpr1a-null embryos, which fail to gastrulate, Bmpr-MORE embryos initiate gastrulation, but the recruitment of prospective paraxial mesoderm cells to the primitive streak is delayed. This delay causes a more proximal distribution of cells with paraxial mesoderm character within the primitive streak, resulting in a lateral expansion of somitic mesoderm to form multiple columns. Inhibition of FGF signaling restores the normal timing of recruitment of prospective paraxial mesoderm and partially rescues the development of somites. This suggests that BMP and FGF signaling function antagonistically during paraxial mesoderm development.
Miura
Shigeto
S
Laboratory of Reproductive and Developmental Toxicology, National Institute of Environmental Health Sciences, MD C4-10, C458, Research Triangle Park, NC 27709, USA.
Davis
Shannon
S
Klingensmith
John
J
Mishina
Yuji
Y
D000818:Animals; D019521:Body Patterning / Q000235:genetics*; D052005:Bone Morphogenetic Protein Receptors, Type I / Q000037:antagonists & inhibitors / Q000235:genetics / Q000502:physiology*; D019485:Bone Morphogenetic Proteins / Q000502:physiology; D047108:Embryonic Development / Q000235:genetics; D005346:Fibroblast Growth Factors / Q000037:antagonists & inhibitors / Q000235:genetics / Q000502:physiology*; D008648:Mesoderm / Q000166:cytology / Q000502:physiology; D051379:Mice; D008817:Mice, Mutant Strains; D051496:Receptor, Fibroblast Growth Factor, Type 1 / Q000037:antagonists & inhibitors / Q000235:genetics / Q000502:physiology*; D015398:Signal Transduction / Q000235:genetics; D019170:Somites / Q000166:cytology / Q000502:physiology*
D019485:Bone Morphogenetic Proteins; D005346:Fibroblast Growth Factors; C496349:Fgfr1 protein, mouse; D051496:Receptor, Fibroblast Growth Factor, Type 1; C498212:Bmpr1a protein, mouse; D052005:Bone Morphogenetic Protein Receptors, Type I