Biomaterial Database

N-glycans of Phaeodactylum tricornutum diatom and functional characterization of its N-acetylglucosaminyltransferase I enzyme. 2011

Bérengère Baïet, and Carole Burel, and Bruno Saint-Jean, and Romain Louvet, and Laurence Menu-Bouaouiche, and Marie-Christine Kiefer-Meyer, and Elodie Mathieu-Rivet, and Thomas Lefebvre, and Hélène Castel, and Aude Carlier, and Jean-Paul Cadoret, and Patrice Lerouge, and Muriel Bardor

Université de Rouen, Laboratoire Glycobiologie et Matrice Extracellulaire Végétale, Faculté des Sciences, 76821 Mont-Saint-Aignan Cédex, France.

N-glycosylation, a major co- and post-translational event in the synthesis of proteins in eukaryotes, is unknown in aquatic photosynthetic microalgae. In this paper, we describe the N-glycosylation pathway in the diatom Phaeodactylum tricornutum. Bio-informatic analysis of its genome revealed the presence of a complete set of sequences potentially encoding for proteins involved in the synthesis of the lipid-linked Glc(3)Man(9)GlcNAc(2)-PP-dolichol N-glycan, some subunits of the oligosaccharyltransferase complex, as well as endoplasmic reticulum glucosidases and chaperones required for protein quality control and, finally, the α-mannosidase I involved in the trimming of the N-glycan precursor into Man-5 N-glycan. Moreover, one N-acetylglucosaminyltransferase I, a Golgi glycosyltransferase that initiates the synthesis of complex type N-glycans, was predicted in the P. tricornutum genome. We demonstrated that this gene encodes for an active N-acetylglucosaminyltransferase I, which is able to restore complex type N-glycans maturation in the Chinese hamster ovary Lec1 mutant, defective in its endogeneous N-acetylglucosaminyltransferase I. Consistent with these data, the structural analyses of N-linked glycans demonstrated that P. tricornutum proteins carry mainly high mannose type N-glycans ranging from Man-5 to Man-9. Although representing a minor glycan population, paucimannose N-glycans were also detected, suggesting the occurrence of an N-acetylglucosaminyltransferase I-dependent maturation of N-glycans in this diatom.

UI	MeSH Term	Description	Entries
D008969	Molecular Sequence Data	Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.	Sequence Data, Molecular,Molecular Sequencing Data,Data, Molecular Sequence,Data, Molecular Sequencing,Sequencing Data, Molecular
D009154	Mutation	Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.	Mutations
D011134	Polysaccharides	Long chain polymeric CARBOHYDRATES composed of MONOSACCHARIDES linked by glycosidic bonds.	Glycan,Glycans,Polysaccharide
D003412	Cricetulus	A genus of the family Muridae consisting of eleven species. C. migratorius, the grey or Armenian hamster, and C. griseus, the Chinese hamster, are the two species used in biomedical research.	Hamsters, Armenian,Hamsters, Chinese,Hamsters, Grey,Armenian Hamster,Armenian Hamsters,Chinese Hamster,Chinese Hamsters,Grey Hamster,Grey Hamsters,Hamster, Armenian,Hamster, Chinese,Hamster, Grey
D004721	Endoplasmic Reticulum	A system of cisternae in the CYTOPLASM of many cells. In places the endoplasmic reticulum is continuous with the plasma membrane (CELL MEMBRANE) or outer membrane of the nuclear envelope. If the outer surfaces of the endoplasmic reticulum membranes are coated with ribosomes, the endoplasmic reticulum is said to be rough-surfaced (ENDOPLASMIC RETICULUM, ROUGH); otherwise it is said to be smooth-surfaced (ENDOPLASMIC RETICULUM, SMOOTH). (King & Stansfield, A Dictionary of Genetics, 4th ed)	Ergastoplasm,Reticulum, Endoplasmic
D005816	Genetic Complementation Test	A test used to determine whether or not complementation (compensation in the form of dominance) will occur in a cell with a given mutant phenotype when another mutant genome, encoding the same mutant phenotype, is introduced into that cell.	Allelism Test,Cis Test,Cis-Trans Test,Complementation Test,Trans Test,Allelism Tests,Cis Tests,Cis Trans Test,Cis-Trans Tests,Complementation Test, Genetic,Complementation Tests,Complementation Tests, Genetic,Genetic Complementation Tests,Trans Tests
D006056	Golgi Apparatus	A stack of flattened vesicles that functions in posttranslational processing and sorting of proteins, receiving them from the rough ENDOPLASMIC RETICULUM and directing them to secretory vesicles, LYSOSOMES, or the CELL MEMBRANE. The movement of proteins takes place by transfer vesicles that bud off from the rough endoplasmic reticulum or Golgi apparatus and fuse with the Golgi, lysosomes or cell membrane. (From Glick, Glossary of Biochemistry and Molecular Biology, 1990)	Golgi Complex,Apparatus, Golgi,Complex, Golgi
D006224	Cricetinae	A subfamily in the family MURIDAE, comprising the hamsters. Four of the more common genera are Cricetus, CRICETULUS; MESOCRICETUS; and PHODOPUS.	Cricetus,Hamsters,Hamster
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000595	Amino Acid Sequence	The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.	Protein Structure, Primary,Amino Acid Sequences,Sequence, Amino Acid,Sequences, Amino Acid,Primary Protein Structure,Primary Protein Structures,Protein Structures, Primary,Structure, Primary Protein,Structures, Primary Protein