title: Chondroitin 6-O-sulfotransferases are required for morphogenesis of the notochord in the ascidian embryo.
abstract: BACKGROUND
  Chondroitin sulfate (CS) is a sulfated polysaccharide chain that binds to various core proteins to form proteoglycans. The amount and position of sulfate groups in CS are variable among different tissues, and are determined by specific sulfotransferases. Although the ascidians are the closest relatives of vertebrates, the functions of their sulfotransferases have not been studied.
  
  
  RESULTS
  The genome of the ascidian Ciona intestinalis contains eight genes encoding proteins similar to chondroitin 6-O-sulfotransferases (C6STs), which appear to have independently diverged in the ascidian lineage during evolution. Among them, Ci-C6ST-like1 and Ci-C6ST-like7 were predominantly expressed in the developing notochord. In addition, they were weakly expressed in the neural tube. The disruption of either one of them affected the convergent extension movement of notochordal cells. Presumptive notochord cells coming from both sides of the embryo did not intercalate. The results suggest that both of them are necessary. In some cases, the anterior neural tube failed to close. Forced expression of Ci-C6ST-like1 or Ci-C6ST-like7 in the notochord restored the normal intercalation of notochordal cells, indicating that the effects of morpholino oligos are specific.
  
  
  CONCLUSIONS
  Ci-C6ST-like1 and Ci-C6ST-like7 are required for the morphogenesis of the notochord in the ascidian embryo.
authors.affiliation: Department of Applied Science, Kochi University, Kochi-shi, Kochi, Japan.
authors.forename: Jun
authors.initials: J
authors.lastname: Nakamura
authors.forename: Keita
authors.initials: K
authors.lastname: Yoshida
authors.forename: Yasunori
authors.initials: Y
authors.lastname: Sasakura
authors.forename: Shigeki
authors.initials: S
authors.lastname: Fujiwara
mesh_terms: D000818:Animals; D002938:Ciona intestinalis / Q000166:cytology / Q000196:embryology* / Q000235:genetics; D004625:Embryo, Nonmammalian / Q000166:cytology / Q000196:embryology*; D018507:Gene Expression Regulation, Developmental / Q000502:physiology; D015971:Gene Expression Regulation, Enzymologic / Q000502:physiology; D055785:Gene Knockdown Techniques; D009672:Notochord / Q000166:cytology / Q000196:embryology*; D038081:Organogenesis / Q000502:physiology*; D015238:Sulfotransferases / Q000096:biosynthesis* / Q000235:genetics; D000097811:Carbohydrate Sulfotransferases
chemical_list: D015238:Sulfotransferases; D000097811:Carbohydrate Sulfotransferases
keywords: Ascidian; chondroitin sulfate; morphogenesis; notochord; sulfotransferase