title: XIdax, an inhibitor of the canonical Wnt pathway, is required for anterior neural structure formation in Xenopus.
abstract: Wnt signaling pathways are involved during various stages in the development of many species. In Xenopus, the accumulation of beta-catenin on the dorsal side of embryo is required for induction of the organizer, while the head structure formation requires inhibition of Wnt signaling. Here, we report a role for xIdax, a negative regulator of Wnt signaling. XIdax is expressed in neural tissues at the neurula stage, and in the restricted region of the tadpole brain. Ectopic expression of xIdax inhibits the target gene expression, suggesting that xIdax can inhibit canonical Wnt signaling. To examine the function of xIdax, a morpholino oligo for xIdax (xIdaxMO) was designed. An injection into an animal pole cell caused a loss of forebrain. The anterior neural marker expression is decreased in xIdaxMO-injected embryo, suggesting that xIdax is required for anterior neural development. Moreover, a negative regulator that acts downstream of xIdax rescued this defect. We propose that Idax functions are dependent on the canonical Wnt pathway and are crucial for the anterior neural development.
authors.affiliation: Department of Life Science (Biology), Graduate School of Arts and Sciences, University of Tokyo, Tokyo, Japan.
authors.forename: Tatsuo
authors.initials: T
authors.lastname: Michiue
authors.forename: Akimasa
authors.initials: A
authors.lastname: Fukui
authors.forename: Akira
authors.initials: A
authors.lastname: Yukita
authors.forename: Kenji
authors.initials: K
authors.lastname: Sakurai
authors.forename: Hiroki
authors.initials: H
authors.lastname: Danno
authors.forename: Akira
authors.initials: A
authors.lastname: Kikuchi
authors.forename: Makoto
authors.initials: M
authors.lastname: Asashima
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D015153:Blotting, Western; D019521:Body Patterning; D001921:Brain / Q000196:embryology; D002352:Carrier Proteins / Q000235:genetics* / Q000378:metabolism / Q000502:physiology*; D003001:Cloning, Molecular; D003593:Cytoplasm / Q000378:metabolism; D003598:Cytoskeletal Proteins / Q000378:metabolism; D004268:DNA-Binding Proteins; D017403:In Situ Hybridization; D008957:Models, Genetic; D008969:Molecular Sequence Data; D009420:Nervous System / Q000196:embryology*; D009474:Neurons / Q000378:metabolism*; D010957:Plasmids / Q000378:metabolism; D011518:Proto-Oncogene Proteins / Q000378:metabolism; D012313:RNA / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017386:Sequence Homology, Amino Acid; D015398:Signal Transduction; D013997:Time Factors; D015534:Trans-Activators / Q000378:metabolism; D014157:Transcription Factors; D051153:Wnt Proteins; D014981:Xenopus; D029867:Xenopus Proteins / Q000235:genetics* / Q000502:physiology*; D051176:beta Catenin
chemical_list: C495266:CTNNB1 protein, Xenopus; C494183:CXXC4 protein, Xenopus; C418221:CXXC4 protein, human; D002352:Carrier Proteins; D003598:Cytoskeletal Proteins; D004268:DNA-Binding Proteins; D011518:Proto-Oncogene Proteins; D015534:Trans-Activators; D014157:Transcription Factors; D051153:Wnt Proteins; D029867:Xenopus Proteins; D051176:beta Catenin; D012313:RNA