title: EXT gene family member rib-2 is essential for embryonic development and heparan sulfate biosynthesis in Caenorhabditis elegans.
abstract: EXT gene family members including EXT1, EXT2, and EXTL2 are glycosyltransferases required for heparan sulfate biosynthesis. To examine the biological functions of rib-2, a member of the Caenorhabditis elegans EXT gene family, we generated a mutant worm lacking the rib-2 gene using the UV-TMP method followed by sib-selection. Inactivation of rib-2 alleles induced developmental abnormalities in F2 and F3 homozygous worms, while F1 heterozygotes showed a normal morphology. The F2 homozygous progeny generated from the F1 heterozygous hermaphrodites somehow developed to adult stage but exhibited abnormal characteristics such as developmental delay and egg-laying defects. The F3 homozygous progeny from the F2 homozygous hermaphrodites showed early developmental defects and most of the F3 worms stopped developing during the gastrulation stage. Whole-mount staining analysis for heparan sulfate using Toluidine blue (pH 2.5) revealed a defect of heparan sulfate biosynthesis in the F2 homozygotes. The analysis using fluorometric post-column high-performance liquid chromatography also uncovered reduced production of heparan sulfate in the rib-2 mutant. These results indicate that rib-2 is essential for embryonic development and heparan sulfate biosynthesis in C. elegans.
authors.affiliation: Department of Molecular Gerontology, Tokyo Metropolitan Institute of Gerontology, 35-2 Sakaecho, Itabashi-ku, Tokyo 173-0015, Japan.
authors.forename: Hidenori
authors.initials: H
authors.lastname: Morio
authors.forename: Yoko
authors.initials: Y
authors.lastname: Honda
authors.forename: Hidenao
authors.initials: H
authors.lastname: Toyoda
authors.forename: Mitsunari
authors.initials: M
authors.lastname: Nakajima
authors.forename: Hisashi
authors.initials: H
authors.lastname: Kurosawa
authors.forename: Takuji
authors.initials: T
authors.lastname: Shirasawa
mesh_terms: D000818:Animals; D002107:Caenorhabditis / Q000166:cytology / Q000196:embryology* / Q000235:genetics / Q000254:growth & development*; D029742:Caenorhabditis elegans Proteins; D002807:Chondroitin / Q000378:metabolism; D004187:Disaccharides / Q000378:metabolism; D017238:Genes, Helminth; D006497:Heparan Sulfate / Q000096:biosynthesis*; D005810:Multigene Family; D009154:Mutation; D017351:N-Acetylglucosaminyltransferases / Q000235:genetics / Q000378:metabolism*; D010641:Phenotype
chemical_list: D029742:Caenorhabditis elegans Proteins; D002807:Chondroitin; D004187:Disaccharides; D006497:Heparan Sulfate; D017351:N-Acetylglucosaminyltransferases; C429019:Rib-2 protein, C elegans