Interaction of N-linked glycans, having multivalent GlcNAc termini, with GM3 ganglioside

Abstract

GM3 ganglioside interacts specifically with complex-type N-linked glycans having multivalent GlcNAc termini, as shown for (1) and (2) below. (1) Oligosaccharides (OS) isolated from ConA-non-binding N-linked glycans of ovalbumin, whose structures were identified as penta-antennary complex-type with bisecting GlcNAc, having five or six GlcNAc termini (OS B1, B2), or bi-antennary complex-type having two GlcNAc termini (OS I). OS I is a structure not previously described. (2) Multi-antennary complex-type N-linked OS isolated from fetuin, treated by sialidase followed by beta-galactosidase, having three or four GlcNAc termini exposed. These OS, conjugated to phosphatidylethanolamine (PE), showed clear interaction with (3)H-labeled liposomes containing GM3, when various doses of OS-PE conjugate were adhered by drying to multi-well polystyrene plates. Interaction was clearly observed only with liposomes containing GM3, but not LacCer, Gb4, or GalNAcalpha1-3Gb4 (Forssman antigen). GM3 interaction with PE conjugate of OS B1 or B2 was stronger than that with PE conjugate of OS I. GM3 interacted clearly with PE conjugate of N-linked OS from desialylated and degalactosylated fetuin, but not native fetuin. No binding was observed to cellobiose-PE conjugate, or to OS-PE conjugate lacking GlcNAc terminus. Thus, GM3, but not other GSL liposomes, interacts with various N-linked OS having multiple GlcNAc termini, in general. These findings suggest that the concept of carbohydrate-to-carbohydrate interaction can be extended to interaction of specific types of N-linked glycans with specific GSLs. Natural occurrence of such interaction to define cell biological phenomena is under investigation.

Functional role of glycosphingolipids and gangliosides in control of cell adhesion, motility, and growth, through glycosynaptic microdomains

“…For example, GM3 is known to interact with the extracellular domain of the epidermal growth factor receptor (EGFR) to inhibit receptor tyrosine kinase [29], but the mechanism and site of EGFR for such interaction has been unclear. GM3 was recently shown to interact with a specific N-linked glycan having multivalent GlcNAc termini [60]. The increased expression of N-glycans with GlcNAc termini in cells treated with swainsonine, which inhibits α-mannosidase-II, causing accumulation of hybridtype structures having GlcNAc termini, was closely associated with the inhibitory effect of GM3 on EGFR tyrosine kinase (Fig.…”

Lowering Glycosphingolipid Levels in CD4+ T Cells Attenuates T Cell Receptor Signaling, Cytokine Production, and Differentiation to the Th17 Lineage

“…Although it is unclear how GSLs influenced TCR signaling in the studies reported here, the ability of such lipids to affect other signaling entities is not without precedence. For example, GM3 has been reported to interact with the epidermal growth factor receptor via the N-acetylglucosamine moieties present on its oligosaccharide side chains (35,36). This association of GM3 with the receptor has been implicated as a potential mode by which its tyrosine kinase and signaling activities are modulated.…”

Structure and function of glycosphingolipids and sphingolipids: Recollections and future trends

“…We found that GM3 bound strongly to a specific complex-type N-linked glycans with 5-6 GlcNAc termini (e.g., "Os. Fr.B"), to a lesser degree to glycans with 3-4 GlcNAc termini, and essentially did not bind to glycans with 2 GlcNAc termini [151]. GM3 interaction with EGFR, which has been known for years (see Sec.…”