Nanoprobe-based affinity mass spectrometry strategy for deciphering galectin-8-binding glycotopes and interplay signaling network

摘要

Galectins, β-galactosides-binding lectins, play important roles in cancer progression by protein-carbohydrate recognition and protein-protein interaction. The binding partners and the corresponding glycan structures in blood samples under physiological and pathological conditions were reported only for the most well-studied galectin-1 and -3 by affinity chromatography-mass spectrometry method. Galectin-8 has been reported for inhibition for cell adhesion and tumor metastasis, and dissociation constants for oligosaccharides has been determined. However, the direct recognition glycotope and regulation signaling are still unclear. Due to the week interaction between galectins and recognized glycoproteins, it is challenging to directly identify endogenous binding partner and study its specific glycotope, if any. mass spectrometry (MS)-based proteomics has become the most powerful method for deciphering glycoproteome, glycosylation sites, and glycome profiling. Moreover, functionalized magnetic nanoparticles (MNPs) provides advantages of its high surface area for ligand functionalization, high density of ligand for enhanced affinity and easy separation by magnetic property, which can be implemented as affinity probe. Therefore, we aim to develop a nanoprobe-based affinity purification strategy integrating mass spectrometry analysis to study the interactome, glycotope recognition of galectin-8.