Wnt-3a is required for somite specification along the anteroposterior axis of the mouse embryo and for regulation of cdx-1 expression.
In vertebrates, each vertebra along the anteroposterior axis has a characteristic structure. It has recently been shown that several transcription factors and cell signaling molecules expressed in the primitive streak ectoderm and/or the tailbud play essential roles in establishing the correct anteroposterior specification of vertebrae during mouse development. Here, we report that Wnt-3a mutants exhibit homeotic transformations in the vertebrae along their entire body axis. In addition, reduced expression of cdx-1, the mutation of which results in an anterior transformation, as occurs in Wnt-3a mutants, was observed in the primitive streak and tail bud region of Wnt-3a mutant embryos. These results indicate that Wnt-3a is necessary for correct anteroposterior patterning of vertebra, and that cdx-1 may be one of the mediator genes of Wnt-3a signaling in this process.
Ikeya
M
M
Center for Molecular and Developmental Biology, Graduate School of Science, Kyoto University, Kitashirakawa, Sakyo-ku, 606-8502, Kyoto, Japan.
Takada
S
S
D000483:Alleles; D000818:Animals; D030161:Avian Proteins; D001842:Bone and Bones / Q000002:abnormalities; D019070:Cell Lineage; D015536:Down-Regulation; D004475:Ectoderm / Q000378:metabolism; D004622:Embryo, Mammalian / Q000378:metabolism*; D018507:Gene Expression Regulation, Developmental; D018398:Homeodomain Proteins / Q000096:biosynthesis* / Q000235:genetics / Q000378:metabolism; D017403:In Situ Hybridization; D051379:Mice; D008957:Models, Genetic; D009154:Mutation; D009432:Neural Crest / Q000378:metabolism; D011506:Proteins / Q000235:genetics* / Q000502:physiology*; D015398:Signal Transduction; D013131:Spine / Q000378:metabolism / Q000502:physiology; D014157:Transcription Factors; D051153:Wnt Proteins; D060508:Wnt3 Protein; D060509:Wnt3A Protein
D030161:Avian Proteins; C491272:Cdx1 protein, mouse; D018398:Homeodomain Proteins; D011506:Proteins; D014157:Transcription Factors; D051153:Wnt Proteins; D060508:Wnt3 Protein; D060509:Wnt3A Protein; C555511:Wnt3a protein, mouse