title: Novel genes involved in canonical Wnt/beta-catenin signaling pathway in early Ciona intestinalis embryos.
abstract: We report here characterization of five genes for novel components of the canonical Wnt/beta-catenin signaling pathway. These genes were identified in the ascidian Ciona intestinalis through a loss-of-function screening for genes required for embryogenesis with morpholinos, and four of them have counterparts in vertebrates. The five genes we studied are as follows: Ci-PGAP1, a Ciona orthologue of human PGAP1, which encodes GPI (glycosylphosphatidylinositol) inositol-deacylase, Ci-ZF278, a gene encoding a C2H2 zinc-finger protein, Ci-C10orf11, a Ciona orthologue of human C10orf11 that encodes a protein with leucine-rich repeats, Ci-Spatial/C4orf17, a single counterpart for two human genes Spatial and C4orf17, and Ci-FLJ10634, a Ciona orthologue of human FLJ10634 that encodes a member of the J-protein family. Knockdown of each of the genes mimicked beta-catenin knockdown and resulted in suppression of the expression of beta-catenin downstream genes (Ci-FoxD, Ci-Lhx3, Ci-Otx and Ci-Fgf9/16/20) and subsequent endoderm formation. For every gene, defects in knockdown embryos were rescued by overexpression of a constitutively active form, but not wild-type, of Ci-beta-catenin. Dosage-sensitive interactions were found between Ci-beta-catenin and each of the genes. These results suggest that these five genes act upstream of or parallel to Ci-beta-catenin in the Wnt/beta-catenin signaling pathway in early Ciona embryos.
authors.affiliation: CREST (Core Research for Evolutional Science and Technology), Japan Science Technology Agency, Kawaguchi, Saitama 333-0012, Japan.
authors.forename: Shuichi
authors.initials: S
authors.lastname: Wada
authors.forename: Mayuko
authors.initials: M
authors.lastname: Hamada
authors.forename: Kenji
authors.initials: K
authors.lastname: Kobayashi
authors.forename: Nori
authors.initials: N
authors.lastname: Satoh
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002938:Ciona intestinalis / Q000196:embryology* / Q000235:genetics / Q000378:metabolism; D015536:Down-Regulation; D004625:Embryo, Nonmammalian / Q000378:metabolism*; D018507:Gene Expression Regulation, Developmental; D008969:Molecular Sequence Data; D010744:Phosphoric Monoester Hydrolases; D015398:Signal Transduction; D051153:Wnt Proteins / Q000235:genetics / Q000378:metabolism*; D051176:beta Catenin / Q000235:genetics / Q000378:metabolism*
chemical_list: D051153:Wnt Proteins; D051176:beta Catenin; D010744:Phosphoric Monoester Hydrolases