Proteomics and glycomics analyses of N-glycosylated structures involved in Toxoplasma gondii--host cell interactions.
The apicomplexan parasite Toxoplasma gondii recognizes, binds, and penetrates virtually any kind of mammalian cell using a repertoire of proteins released from late secretory organelles and a unique form of gliding motility (also named glideosome) that critically depends on actin filaments and myosin. How T. gondii glycosylated proteins mediate host-parasite interactions remains elusive. To date, only limited evidence is available concerning N-glycosylation in apicomplexans. Here we report comprehensive proteomics and glycomics analyses showing that several key components required for host cell-T. gondii interactions are N-glycosylated. Detailed structural characterization confirmed that N-glycans from T. gondii total protein extracts consist of oligomannosidic (Man(5-8)(GlcNAc)2) and paucimannosidic (Man(3-4)(GlcNAc)2) sugars, which are rarely present on mature eukaryotic glycoproteins. In situ fluorescence using concanavalin A and Pisum sativum agglutinin predominantly stained the entire parasite body. Visualization of Toxoplasma glycoproteins purified by affinity chromatography followed by detailed proteomics and glycan analyses identified components involved in gliding motility, moving junction, and other additional functions implicated in intracellular development. Importantly tunicamycin-treated parasites were considerably reduced in motility, host cell invasion, and growth. Collectively these results indicate that N-glycosylation probably participates in modifying key proteins that are essential for host cell invasion by T. gondii.
Fauquenoy
Sylvain
S
Unité de Glycobiologie Structurale et Fonctionnelle, CNRS UMR 8576, Université des Sciences et Technologies de Lille, 59655 Villeneuve d'Ascq, France.
Morelle
Willy
W
Hovasse
Agnès
A
Bednarczyk
Audrey
A
Slomianny
Christian
C
Schaeffer
Christine
C
Van Dorsselaer
Alain
A
Tomavo
Stanislas
S
D000818:Animals; D002240:Carbohydrate Sequence; D002478:Cells, Cultured; D054794:Glycomics; D006023:Glycoproteins / Q000032:analysis / Q000378:metabolism*; D006031:Glycosylation; D006790:Host-Parasite Interactions; D006801:Humans; D018613:Microscopy, Confocal; D008969:Molecular Sequence Data; D009844:Oligosaccharides / Q000032:analysis; D043524:Peptide-N4-(N-acetyl-beta-glucosaminyl) Asparagine Amidase / Q000737:chemistry; D037121:Plant Lectins / Q000737:chemistry; D011134:Polysaccharides / Q000737:chemistry; D040901:Proteomics; D015800:Protozoan Proteins / Q000032:analysis / Q000378:metabolism*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D014122:Toxoplasma / Q000737:chemistry / Q000378:metabolism / Q000502:physiology*
D006023:Glycoproteins; D009844:Oligosaccharides; D037121:Plant Lectins; D011134:Polysaccharides; D015800:Protozoan Proteins; D043524:Peptide-N4-(N-acetyl-beta-glucosaminyl) Asparagine Amidase