کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
10537052 962664 2015 11 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Site-specific structural characterization of O-glycosylation and identification of phosphorylation sites of recombinant osteopontin
کلمات کلیدی
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی آنالیزی یا شیمی تجزیه
پیش نمایش صفحه اول مقاله
Site-specific structural characterization of O-glycosylation and identification of phosphorylation sites of recombinant osteopontin
چکیده انگلیسی
Osteopontin (OPN) plays a key role in multiple physiological and pathological processes such as cytokine production, mineralization, inflammation, immune responses, and tumorigenesis. Post-translational modifications (PTMs) of OPN significantly affect its structure and biological properties; however, site-specific characterization of O-glycosylation in human OPN has not been reported. In this work, we profiled the overall glycan pattern of human recombinant OPN using a lectin array and completed detailed structural analysis of O-glycopeptides by mass spectrometry (MS). We detected 28 O-glycopeptides from 7 O-glycosylation regions of human OPN, occupied by highly heterogeneous O-glycans. These O-glycans carried, in part, functionally relevant epitopes such as T antigens (Galβ1-3GalNAcα1-), sialyl-Tn antigens, sialyl-T antigens, and sialyl-Lex/a antigens [Neuα2-3Galβ1-4(Fucα1-3)GlcNAc/Neuα2-3Galβ1-3(Fucα1-4)GlcNAc]. MS3 spectra of the generated O-glycopeptides showed cleavages of the peptide backbone and provided essential information on the peptide sequence. Furthermore, 26 phosphorylation sites were identified by reverse-phase liquid chromatography-tandem mass spectrometry (RPLC-MS/MS), including a novel one (Y209). We provide a detailed, site-specific structural characterization of O-glycosylation and identify the phosphorylation sites of OPN. These data lay the foundation for further research into the role of oligosaccharides and phosphorylation of recombinant human OPN. This article is part of a Special Issue entitled: Medical Proteomics.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Biochimica et Biophysica Acta (BBA) - Proteins and Proteomics - Volume 1854, Issue 6, June 2015, Pages 581-591
نویسندگان
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