title: Structures and developmental alterations of N-glycans of zebrafish embryos.
abstract: Zebrafish is a model organism suitable for studying vertebrate development. We analyzed the N-glycan structures of zebrafish embryos and their alterations during zebrafish embryogenesis to obtain basic data for studying the roles of N-glycosylation. Multiple modes of high-performance liquid chromatography and multistage mass spectrometry were used for structural analysis of N-glycans. The N-glycans from deyolked embryos at 36 hours postfertilization, a mid-pharyngula stage, contained relatively higher amounts of complex- and hybrid-type glycans with LacNAc (Galβ1-4GlcNAc) and/or sialyl LacNAc without additional β1,4-Gal, which are commonly found in mammalian tissues, as well as abundant oligomannose-type glycans. Some of the complex- and hybrid-type glycans possessed various extended LacNAc structures, such as Galβ1-4LacNAc, LacNAc-repeat or unique (+/- dHex)-GalNAcα1-GlcNAcβ1-LacNAc. In contrast, the yolk of the embryo contains predominant oligomannose-type glycans and complex-type glycans with Galβ1-4(Siaα2-3)Galβ1-4(Fucα1-3)GlcNAc antennae. N-Glycan profiles obtained from deyolked embryos at different stages showed stage-dependent variation of complex- and hybrid-type glycans. At gastrula and early segmentation stages, complex- and hybrid-type glycans were minor components, and their antenna structures were mainly sialyl LacdiNAc (Siaα2-6GalNAcβ1-4GlcNAc). From the mid-segmentation to pharyngula stages, those with LacNAc and/or α2,6-sialyl LacNAc antenna structures increased remarkably, and those with α2,3-sialyl LacNAc antenna, core α1,6-Fuc and bisecting GlcNAc modifications increased gradually. These results suggest the presence of mechanisms for regulating the antenna structures of complex/hybrid N-glycan biosynthesis in the phylotypic stage of vertebrate development.
authors.affiliation: Department of Food and Life Sciences, Graduate School of Science and Technology,  Niigata University, 8050 Ikarashi-nino-cho, Nishi-ku, Niigata 950-2181, Japan.
authors.forename: Ken
authors.initials: K
authors.lastname: Hanzawa
authors.affiliation: Department of Food and Life Sciences, Graduate School of Science and Technology,  Niigata University, 8050 Ikarashi-nino-cho, Nishi-ku, Niigata 950-2181, Japan.|Department of Biology, Niigata University, 8050 Ikarashi-nino-cho, Nishi-ku, Niigata 950-2181, Japan.
authors.forename: Noriko
authors.initials: N
authors.lastname: Suzuki
authors.affiliation: Department of Food and Life Sciences, Graduate School of Science and Technology,  Niigata University, 8050 Ikarashi-nino-cho, Nishi-ku, Niigata 950-2181, Japan.|Department of Biology, Niigata University, 8050 Ikarashi-nino-cho, Nishi-ku, Niigata 950-2181, Japan.
authors.forename: Shunji
authors.initials: S
authors.lastname: Natsuka
mesh_terms: D000818:Animals; D002240:Carbohydrate Sequence; D002851:Chromatography, High Pressure Liquid; D004625:Embryo, Nonmammalian / Q000737:chemistry / Q000378:metabolism; D047108:Embryonic Development; D005700:Galactosyltransferases / Q000737:chemistry / Q000378:metabolism; D005775:Gastrula / Q000254:growth & development / Q000378:metabolism; D006031:Glycosylation; D007785:Lactose / Q000031:analogs & derivatives / Q000737:chemistry / Q000378:metabolism; D011134:Polysaccharides / Q000737:chemistry* / Q000378:metabolism; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D015027:Zebrafish / Q000235:genetics / Q000378:metabolism*
chemical_list: D011134:Polysaccharides; C093701:N-acetylgalactosaminyl-1-4-N-acetylglucosamine; D005700:Galactosyltransferases; C038887:N-acetyllactosamine alpha-D-galactosyltransferase; D007785:Lactose
keywords: HPLC; LacNAc; N-glycosylation; multistage mass spectrometry; zebrafish