Full-length Galectin-8 and separate carbohydrate recognition domains: the whole is greater than the sum of its parts?

CAGNONI, ALEJANDRO J.; MARÍA FERNANDA TRONCOSO; RABINOVICH, GABRIEL A.; MARIÑO, KARINA V.; MARIA TERESA ELOLA

BIOCHEMICAL SOCIETY TRANSACTIONS

PORTLAND PRESS LTD

Lugar: Londres; Año: 2020

0300-5127

Galectin-8 (Gal-8) is a tandem-repeat type galectin with affinity for β-galactosides, bearing twocarbohydrate recognition domains (CRD) connected by a linker peptide. The N- and C-terminaldomains (Gal-8N and Gal-8C) share 35% homology, and their glycan ligand specificity is notablydissimilar: while Gal-8N shows strong affinity for α(2-3)-sialylated oligosaccharides, Gal-8C hashigher affinity for non-sialylated oligosaccharides, including poly-N-acetyllactosamine and/ or A and Bblood group structures. Particularly relevant for understanding the biological role of this lectin, fulllengthGal-8 can bind cell surface glycoconjugates with broader affinity than the isolated Gal-8N andGal-8C domains, a trait also described for other tandem-repeat galectins. Herein, we aim to discuss thepotential use of separate CRDs in modelling tandem-repeat galectin-8 and its biological functions. Forthis purpose, we will cover several aspects of the structure-function relationship of this proteinincluding crystallographic structures, glycan specificity, cell function and biological roles, with theultimate goal of understanding the potential role of each CRD in predicting full-length Gal-8involvement in relevant biological processes.