title: Integrative view of α2,3-sialyltransferases (ST3Gal) molecular and functional evolution in deuterostomes: significance of lineage-specific losses.
abstract: Sialyltransferases are responsible for the synthesis of a diverse range of sialoglycoconjugates predicted to be pivotal to deuterostomes' evolution. In this work, we reconstructed the evolutionary history of the metazoan α2,3-sialyltransferases family (ST3Gal), a subset of sialyltransferases encompassing six subfamilies (ST3Gal I-ST3Gal VI) functionally characterized in mammals. Exploration of genomic and expressed sequence tag databases and search of conserved sialylmotifs led to the identification of a large data set of st3gal-related gene sequences. Molecular phylogeny and large scale sequence similarity network analysis identified four new vertebrate subfamilies called ST3Gal III-r, ST3Gal VII, ST3Gal VIII, and ST3Gal IX. To address the issue of the origin and evolutionary relationships of the st3gal-related genes, we performed comparative syntenic mapping of st3gal gene loci combined to ancestral genome reconstruction. The ten vertebrate ST3Gal subfamilies originated from genome duplication events at the base of vertebrates and are organized in three distinct and ancient groups of genes predating the early deuterostomes. Inferring st3gal gene family history identified also several lineage-specific gene losses, the significance of which was explored in a functional context. Toward this aim, spatiotemporal distribution of st3gal genes was analyzed in zebrafish and bovine tissues. In addition, molecular evolutionary analyses using specificity determining position and coevolved amino acid predictions led to the identification of amino acid residues with potential implication in functional divergence of vertebrate ST3Gal. We propose a detailed scenario of the evolutionary relationships of st3gal genes coupled to a conceptual framework of the evolution of ST3Gal functions.
authors.affiliation: INRA, UMR 1061, Unité Génétique Moléculaire Animale, F-87060 Limoges Cedex, France Université de Limoges, UMR 1061, Unité Génétique Moléculaire Animale, 123 avenue Albert Thomas, F-87060 Limoges Cedex, France.
authors.forename: Daniel
authors.initials: D
authors.lastname: Petit
authors.affiliation: Bioinformatics Unit, Fundación Instituto Leloir, Buenos Aires, Argentina.
authors.forename: Elin
authors.initials: E
authors.lastname: Teppa
authors.affiliation: Laboratoire de Glycobiologie Structurale et Fonctionnelle, UMR 8576 CNRS, Université Lille Nord de France, Lille1, Villeneuve d'Ascq, France.
authors.forename: Anne-Marie
authors.initials: AM
authors.lastname: Mir
authors.affiliation: Laboratoire de Glycobiologie Structurale et Fonctionnelle, UMR 8576 CNRS, Université Lille Nord de France, Lille1, Villeneuve d'Ascq, France.
authors.forename: Dorothée
authors.initials: D
authors.lastname: Vicogne
authors.affiliation: Department of Cell Biology, School of Medicine, University of Virginia.
authors.forename: Christine
authors.initials: C
authors.lastname: Thisse
authors.affiliation: Department of Cell Biology, School of Medicine, University of Virginia.
authors.forename: Bernard
authors.initials: B
authors.lastname: Thisse
authors.affiliation: INRA, UMR 1061, Unité Génétique Moléculaire Animale, F-87060 Limoges Cedex, France Université de Limoges, UMR 1061, Unité Génétique Moléculaire Animale, 123 avenue Albert Thomas, F-87060 Limoges Cedex, France.
authors.forename: Cyril
authors.initials: C
authors.lastname: Filloux
authors.affiliation: Laboratoire de Glycobiologie Structurale et Fonctionnelle, UMR 8576 CNRS, Université Lille Nord de France, Lille1, Villeneuve d'Ascq, France anne.harduin@univ-lille1.fr.
authors.forename: Anne
authors.initials: A
authors.lastname: Harduin-Lepers
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D043344:Chordata / Q000235:genetics; D004447:Echinodermata / Q000235:genetics; D019143:Evolution, Molecular; D008969:Molecular Sequence Data; D010802:Phylogeny; D012799:Sialyltransferases / Q000235:genetics*; D014714:Vertebrates / Q000235:genetics*; D000094663:beta-Galactoside alpha-2,3-Sialyltransferase
chemical_list: D012799:Sialyltransferases; D000094663:beta-Galactoside alpha-2,3-Sialyltransferase
keywords: coevolved amino acid; evolution rates; genomics; glycobiology; molecular evolution; molecular modeling; phylogenetics; specificity determining position; zebrafish; β-galactoside α2,3-sialyltransferases