A new mouse member of the Wnt gene family, mWnt-8, is expressed during early embryogenesis and is ectopically induced by retinoic acid.
We have identified a novel mouse Wnt genc using a cDNA differential screening procedure for retinoic-acid-induced transcripts in P19 embryonal carcinoma cells. Sequence analysis showed that this gene represents the first murine Wnt-8 (mWnt-8) gene reported to date. The expression of the mWnt-8 gene, which is rapidly induced by retinoic acid in P19 and embryonic stem cells, appears to be restricted to early stages of mouse embryogenesis. mWnt-8 transcripts are first detected in the posterior region of the epiblast of early primitive streak-stage embryos. As gastrulation proceeds, mWnt-8 expression spreads into the embryonic ectoderm up to a sharp rostral boundary at the base of the developing headfolds. mWnt-8 is also transiently expressed in the newly formed mesoderm. mWnt-8 expression is rapidly down-regulated during early somitogenesis, the latest detectable expression domains corresponding to the presumptive fourth rhombomere and the caudal region of the neural plate. The expression pattern of mWnt-8 is clearly distinct from those of other murine Wnt genes expressed during gastrulation, but shows striking similarities with that of the chicken Cwnt-8C gene. We also show that mWnt-8 expression is ectopically induced in the rostral neural plate in response to RA exposure of presumitic (7-7.5 days post coitum) cultured mouse embryos.
Bouillet
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Institut de Génétique et de Biologie Moléculaire et Cellulaire, CNRS/INSERM/ULP/Collège de France, C.U. de Strasbourg, Illkirch, France.
Oulad-Abdelghani
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Ward
S J
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Bronner
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Chambon
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Dollé
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D000367:Age Factors; D000595:Amino Acid Sequence; D000818:Animals; D002645:Chickens; D003001:Cloning, Molecular; D003598:Cytoskeletal Proteins; D004622:Embryo, Mammalian / Q000737:chemistry; D004625:Embryo, Nonmammalian; D017403:In Situ Hybridization; D051379:Mice; D008810:Mice, Inbred C57BL; D008969:Molecular Sequence Data; D009024:Morphogenesis / Q000187:drug effects; D011506:Proteins / Q000235:genetics* / Q000378:metabolism*; D017386:Sequence Homology, Amino Acid; D014018:Tissue Distribution; D014212:Tretinoin / Q000494:pharmacology*; D014407:Tumor Cells, Cultured; D051153:Wnt Proteins; D014981:Xenopus; D015027:Zebrafish; D029961:Zebrafish Proteins
D003598:Cytoskeletal Proteins; D011506:Proteins; D051153:Wnt Proteins; D029961:Zebrafish Proteins; C094521:wnt8a protein, zebrafish; D014212:Tretinoin