From structural to functional glycomics: core substitutions as molecular switches for shape and lectin affinity of N-glycans
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Sabine André
Abstract
Glycan epitopes of cellular glycoconjugates act as versatile biochemical signals (sugar coding). Here, we test the hypothesis that the common N-glycan modifications by core fucosylation and introduction of the bisecting N-acetylglucosamine moiety have long-range effects with functional consequences. Molecular dynamics simulations indicate a shift in conformational equilibria between linear extension or backfolding of the glycan antennae upon substitution. We also present a new fingerprint-like mode of presentation for this multi-parameter system. In order to delineate definite structure-function relationships, we strategically combined chemoenzymatic synthesis with bioassaying cell binding and the distribution of radioiodinated neoglycoproteins in vivo. Of clinical relevance, tailoring the core region affects serum clearance markedly, e.g., prolonging circulation time for the neoglycoprotein presenting the N-glycan with both substitutions. α2,3-Sialylation is another means toward this end, similarly seen for type II branching in triantennary N-glycans. This discovery signifies that rational glycoengineering along the given lines is an attractive perspective to optimize pharmacokinetic behavior of glycosylated pharmaproteins. Of general importance for the concept of the sugar code, the presented results teach the fundamental lesson that N-glycan core substitutions convey distinct characteristics to the concerned oligosaccharide relevant for cis and trans biorecognition processes. These modifications are thus molecular switches.
©2009 by Walter de Gruyter Berlin New York
Articles in the same Issue
- Guest Editorial
- Highlight: Perspectives in glycobiology
- Cell biology and glycosylation: protein targeting by O- and N-linked glycosylation
- Glycosylation- and phosphorylation-dependent intracellular transport of lysosomal hydrolases
- Glycosylation pattern of brush border-associated glycoproteins in enterocyte-like cells: involvement of complex-type N-glycans in apical trafficking
- Impact of glycosylation and detergent-resistant membranes on the function of intestinal sucrase-isomaltase
- MUC1 traverses apical recycling endosomes along the biosynthetic pathway in polarized MDCK cells
- Cell biology and glycosylation: carbohydrate-mediated recognition and signaling in cell proliferation and differentiation
- From structural to functional glycomics: core substitutions as molecular switches for shape and lectin affinity of N-glycans
- Brain development needs sugar: the role of polysialic acid in controlling NCAM functions
- Beyond glycosylation: sialic acid precursors act as signaling molecules and are involved in cellular control of differentiation of PC12 cells
- Glycosylation and disease
- Management of the human mucosal defensive barrier: evidence for glycan legislation
- Regulation and pathophysiological implications of UDP-GlcNAc 2-epimerase/ManNAc kinase (GNE) as the key enzyme of sialic acid biosynthesis
- GD3 synthase overexpression enhances proliferation and migration of MDA-MB-231 breast cancer cells
- Tumor-associated MUC1 glycopeptide epitopes are not subject to self-tolerance and improve responses to MUC1 peptide epitopes in MUC1 transgenic mice
- Protein-specific glycosylation and its control
- Protein-specific glycosylation: signal patches and cis-controlling peptidic elements
- O-glycosylation pattern of CD24 from mouse brain
- Advancements in analytical techniques
- Carbohydrate microarrays: key developments in glycobiology
- On-line nano-HPLC/ESI QTOF MS monitoring of α2–3 and α2–6 sialylation in granulocyte glycosphingolipidome
Articles in the same Issue
- Guest Editorial
- Highlight: Perspectives in glycobiology
- Cell biology and glycosylation: protein targeting by O- and N-linked glycosylation
- Glycosylation- and phosphorylation-dependent intracellular transport of lysosomal hydrolases
- Glycosylation pattern of brush border-associated glycoproteins in enterocyte-like cells: involvement of complex-type N-glycans in apical trafficking
- Impact of glycosylation and detergent-resistant membranes on the function of intestinal sucrase-isomaltase
- MUC1 traverses apical recycling endosomes along the biosynthetic pathway in polarized MDCK cells
- Cell biology and glycosylation: carbohydrate-mediated recognition and signaling in cell proliferation and differentiation
- From structural to functional glycomics: core substitutions as molecular switches for shape and lectin affinity of N-glycans
- Brain development needs sugar: the role of polysialic acid in controlling NCAM functions
- Beyond glycosylation: sialic acid precursors act as signaling molecules and are involved in cellular control of differentiation of PC12 cells
- Glycosylation and disease
- Management of the human mucosal defensive barrier: evidence for glycan legislation
- Regulation and pathophysiological implications of UDP-GlcNAc 2-epimerase/ManNAc kinase (GNE) as the key enzyme of sialic acid biosynthesis
- GD3 synthase overexpression enhances proliferation and migration of MDA-MB-231 breast cancer cells
- Tumor-associated MUC1 glycopeptide epitopes are not subject to self-tolerance and improve responses to MUC1 peptide epitopes in MUC1 transgenic mice
- Protein-specific glycosylation and its control
- Protein-specific glycosylation: signal patches and cis-controlling peptidic elements
- O-glycosylation pattern of CD24 from mouse brain
- Advancements in analytical techniques
- Carbohydrate microarrays: key developments in glycobiology
- On-line nano-HPLC/ESI QTOF MS monitoring of α2–3 and α2–6 sialylation in granulocyte glycosphingolipidome
