Glycan dependence of Galectin-3 self-association properties

PLoS One. 2014 Nov 4;9(11):e111836. doi: 10.1371/journal.pone.0111836. eCollection 2014.

Abstract

Human Galectin-3 is found in the nucleus, the cytoplasm and at the cell surface. This lectin is constituted of two domains: an unfolded N-terminal domain and a C-terminal Carbohydrate Recognition Domain (CRD). There are still uncertainties about the relationship between the quaternary structure of Galectin-3 and its carbohydrate binding properties. Two types of self-association have been described for this lectin: a C-type self-association and a N-type self-association. Herein, we have analyzed Galectin-3 oligomerization by Dynamic Light Scattering using both the recombinant CRD and the full length lectin. Our results proved that LNnT induces N-type self-association of full length Galectin-3. Moreover, from Nuclear Magnetic Resonance (NMR) and Surface Plasmon Resonance experiments, we observed no significant specificity or affinity variations for carbohydrates related to the presence of the N-terminal domain of Galectin-3. NMR mapping clearly established that the N-terminal domain interacts with the CRD. We propose that LNnT induces a release of the N-terminal domain resulting in the glycan-dependent self-association of Galectin-3 through N-terminal domain interactions.

MeSH terms

  • Blood Proteins
  • Galectin 3 / chemistry*
  • Galectins
  • Glycosylation
  • Humans
  • Lactose / chemistry
  • Models, Molecular
  • Oligosaccharides / chemistry
  • Protein Binding
  • Protein Multimerization
  • Protein Processing, Post-Translational
  • Protein Structure, Quaternary

Substances

  • Blood Proteins
  • Galectin 3
  • Galectins
  • LGALS3 protein, human
  • Oligosaccharides
  • lacto-N-neotetraose
  • Lactose

Grants and funding

The authors have no support or funding to report.