T (Brachyury) is a direct target of Wnt3a during paraxial mesoderm specification.
Wnt3a encodes a signal that is expressed in the primitive streak of the gastrulating mouse embryo and is required for paraxial mesoderm development. In its absence cells adopt ectopic neural fates. Embryos lacking the T-box-containing transcription factors, Brachyury or Tbx6, also lack paraxial mesoderm. Here we show that Brachyury is specifically down-regulated in Wnt3a mutants in cells fated to form paraxial mesoderm. Transgenic analysis of the T promoter identifies T (Brachyury) as a direct transcriptional target of the Wnt signaling pathway. Our results suggest that Wnt3a, signaling via Brachyury, modulates a balance between mesodermal and neural cell fates during gastrulation.
Yamaguchi
T P
TP
Department of Molecular Biology, Biological Laboratories, Harvard University, Cambridge, Massachusetts 02138 USA.
Takada
S
S
Yoshikawa
Y
Y
Wu
N
N
McMahon
A P
AP
D000818:Animals; D005314:Embryonic and Fetal Development; D005326:Fetal Proteins; D005775:Gastrula / Q000502:physiology*; D018507:Gene Expression Regulation, Developmental; D006579:Heterozygote; D006720:Homozygote; D008648:Mesoderm / Q000502:physiology*; D051379:Mice; D018345:Mice, Knockout; D008822:Mice, Transgenic; D016297:Mutagenesis, Site-Directed; D011401:Promoter Regions, Genetic; D011506:Proteins / Q000235:genetics* / Q000378:metabolism*; D011994:Recombinant Proteins / Q000378:metabolism; D015398:Signal Transduction; D020825:T-Box Domain Proteins / Q000235:genetics* / Q000378:metabolism*; D051153:Wnt Proteins; D060508:Wnt3 Protein; D060509:Wnt3A Protein; D001616:beta-Galactosidase / Q000235:genetics; D000098908:Brachyury Protein
D005326:Fetal Proteins; D011506:Proteins; D011994:Recombinant Proteins; D020825:T-Box Domain Proteins; D051153:Wnt Proteins; D060508:Wnt3 Protein; D060509:Wnt3A Protein; D001616:beta-Galactosidase; D000098908:Brachyury Protein; C555511:Wnt3a protein, mouse