The Enrichment Technique Strategies in Phosphoproteomics Study

In eukaryotes protein phosphorylation is a key event.By reversible protein phosphorylation eukaryotes control many cellular processes including signal transduction,gene expression,the cell cycle etc.The study of phosphoproteomics involves identification of phosphoproteins and phosphopeptides,localization of the exact residues that are phosphorylated and quantitation of phosphorylation.The detection of phosphopeptides remains challenging because of the low abundance of phosphoproteins.The enrichment of phosphoproteins and phosphopeptides is one of the important ways to improve the MS response of phosphopeptide signals.The methods currently available for the enrichment strategies,including using antibodies,immobilized metal affinity chromatography and metal oxide/hydroxide affinity chromatography were summarized in this review.