An application of electrostatic repulsion hydrophilic interaction chromatography in phospho- and glycoproteome profiling of epicardial adipose tissue in obesity mouse

Abstract

Phosphorylation and glycosylation are two of the most important and widespread post-translational modifications (PTMs) in an organism. Proteomics analysis of the PTMs has been challenged by low stoichiometry of the modified proteins and suppression effects by high abundance proteins, typically no-functional house-keeping proteins. In this study, a novel method was applied for not only isolating PTM peptides from intact peptides but also concurrently characterizing of glyco- and phospho-proteome using electrostatic repulsion hydrophilic interaction chromatography (ERLIC) packed with silica coated by cross-linked polyethyleneimine. For 2 mg tryptic digest of mouse proteome of epicardial adipose tissue with fat diet, 802 N-glycosy-lated peptides of 316 glycoproteins and 159 phosphorylated peptides of 75 phosphoproteins were identified using HPLC chip/ quadrupole time-of-flight (Q-TOF) tandem mass spectrometer.