Proteomic analysis of N-glycosylation of human seminal plasma.

Seminal plasma is a mixture of secretions from several male accessory glands. The seminal plasma contains many secreted proteins which are important for sperm function and male fertility. In this study, we employed N-linked glycosylated peptide enrichment, combined with LC-MS/MS analysis, and establish the first large scale N-linked glycoproteome of human seminal plasma. Combined with the results of five biological replicates, a total of 720 N-glycosylated sites on 372 proteins were identified. Analysis of variations among five individuals revealed similar compositions of N-glycosylated proteins in seminal plasma. The N-linked glycoproteome could help us understanding the biological functions of human seminal plasma. The data set could also be a resource for further screening of biomarkers for male diseases including cancer and infertility at the level of N-glycosylation. For example, N-glycosylated prostate-specific antigen is known to be an efficient biomarker that can distinguish benign prostate hyperplasia from prostate cancer. All MS data have been deposited in the ProteomeXchange with identifier PXD000959 (http://proteomecentral.proteomexchange.org/dataset/PXD000959).