Galectins are a family of β-galactoside-binding lectins carrying at least one consensus sequence in the carbohydrate-recognition domain. Properties of glycosylated ligands, such as N- and O-glycan branching, LacNAc (N-acetyl-lactosamine) content and the balance of α2,3- and α2,6-linked sialic acid dramatically influence galectin binding to a preferential set of counter-receptors. The presentation of specific glycans in galectin-binding partners is also critical, as proper orientation and clustering of oligosaccharide ligands on multiple carbohydrate side chains increase the binding avidity of galectins for particular glycosylated receptors. When galectins are released from the cells, they typically concentrate on the cell surface and the local matrix, raising their local concentration. Thus galectins can form their own multimers in the extracellular milieu, which in turn cross-link glycoconjugates on the cell surface generating galectin–glycan complexes that modulate intracellular signalling pathways, thus regulating cellular processes such as apoptosis, proliferation, migration and angiogenesis. Subtle changes in receptor expression, rates of protein synthesis, activities of Golgi enzymes, metabolite concentrations supporting glycan biosynthesis, density of glycans, strength of protein–protein interactions at the plasma membrane and stoichiometry may modify galectin–glycan complexes. Although galectins are key contributors to the formation of these extended glycan complexes leading to promotion of receptor segregation/clustering, and inhibition of receptor internalization by surface retention, when these complexes are disrupted, some galectins, particularly galectin-3 and -4, showed the ability to drive clathrin-independent mechanisms of endocytosis. In the present review, we summarize the data available on the assembly, hierarchical organization and regulation of conspicuous galectin–glycan complexes, and their implications in health and disease.
Skip Nav Destination
Article navigation
July 2015
- Cover Image
- PDF Icon PDF LinkFront Matter
- PDF Icon PDF LinkTable of Contents
- PDF Icon PDF LinkEditorial Board
Review Article|
June 19 2015
Assembly, organization and regulation of cell-surface receptors by lectin–glycan complexes
María T. Elola
;
María T. Elola
*Institute of Biochemistry and Biophysics (IQUIFIB), National Research Council (CONICET), Biological Chemistry Department, School of Pharmacy and Biochemistry, University of Buenos Aires, Buenos Aires, Argentina
Search for other works by this author on:
Ada G. Blidner
;
Ada G. Blidner
†Laboratory of Immunopathology, Institute of Biology and Experimental Medicine (IBYME), CONICET, Buenos Aires, Argentina
Search for other works by this author on:
Fátima Ferragut
;
Fátima Ferragut
*Institute of Biochemistry and Biophysics (IQUIFIB), National Research Council (CONICET), Biological Chemistry Department, School of Pharmacy and Biochemistry, University of Buenos Aires, Buenos Aires, Argentina
Search for other works by this author on:
Candelaria Bracalente
;
Candelaria Bracalente
*Institute of Biochemistry and Biophysics (IQUIFIB), National Research Council (CONICET), Biological Chemistry Department, School of Pharmacy and Biochemistry, University of Buenos Aires, Buenos Aires, Argentina
Search for other works by this author on:
Gabriel A. Rabinovich
Gabriel A. Rabinovich
1
†Laboratory of Immunopathology, Institute of Biology and Experimental Medicine (IBYME), CONICET, Buenos Aires, Argentina
‡School of Exact and Natural Sciences, University of Buenos Aires, Buenos Aires, Argentina
1To whom correspondence should be addressed (email gabyrabi@gmail.com).
Search for other works by this author on:
Biochem J (2015) 469 (1): 1–16.
Article history
Received:
April 16 2015
Accepted:
May 13 2015
Citation
María T. Elola, Ada G. Blidner, Fátima Ferragut, Candelaria Bracalente, Gabriel A. Rabinovich; Assembly, organization and regulation of cell-surface receptors by lectin–glycan complexes. Biochem J 1 July 2015; 469 (1): 1–16. doi: https://doi.org/10.1042/BJ20150461
Download citation file:
Sign in
Don't already have an account? Register
Sign in to your personal account
You could not be signed in. Please check your email address / username and password and try again.
Biochemical Society Member Sign in
Sign InSign in via your Institution
Sign in via your InstitutionGet Access To This Article
Cited By
Related Articles
[Difluro(phosphono)methyl]phenylalanine-containing peptide inhibitors of protein tyrosine phosphatases
Biochem J (January,1999)
Harmine suppresses bladder tumor growth by suppressing vascular endothelial growth factor receptor 2-mediated angiogenesis
Biosci Rep (May,2019)