Galectins-1, -2 and -3 exhibit differential recognition of sialylated glycans and blood group antigens

Research output: Contribution to journalArticle

Abstract

Human galectins have functionally divergent roles, although most of the members of the galectin family bind weakly to the simple disaccharide lactose (Galss1-4Glc). To assess galectin-glycan interactions in more detail, we explored the binding of several important galectins (Gal-1, Gal-2, and Gal-3) on a glycan microarray containing hundreds of structurally diverse glycans. All three galectins exhibited unique glycan binding characteristics. Only Gal-1 and Gal-2 bound complex-type N-glycans and extended core 1 O-glycans with high affinity, while Gal-2 and Gal-3, but not Gal-1, bound A and B blood group antigens. Gal-2 failed to recognize any sialylated glycans regardless of linkage, whereas Gal-1 and Gal-3 bound a2-3, but not a2-6 sialylated glycans. All galectins showed higher binding to sulfated glycans relative to unsulfated ones. Each galectin exhibited higher binding for glycans with poly-N-acetyllactosamine (PL) sequences (Galss1-4GlcNAc)n when compared to N-acetyllactosamine (Galss1-4GlcNAc) in the microarray. However, only Gal-3 preferred PL when assessed by solution-based surface plasmon resonance. Removal of the terminal galactose residue in PL abrogated its recognition by Gal-1 and Gal-2 while having no substantial effect on Gal-3 recognition, demonstrating that Gal-3 recognizes internal N-acetyllactosamine units. These results provide novel insights into the functional constraints of glycan recognition by each galectin and underscore the basis for differences in biological activity.

Details

Authors
  • Sean R Stowell
  • Connie M Arthur
  • Padmaja Mehta
  • Kristen A Slanina
  • Ola Blixt
  • Hakon Leffler
  • David F Smith
  • Richard D Cummings
Organisations
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Microbiology in the medical area
  • Immunology in the medical area
Original languageEnglish
Pages (from-to)10109-10123
JournalJournal of Biological Chemistry
Volume283
Issue number15
Publication statusPublished - 2008
Publication categoryResearch
Peer-reviewedYes