PMID: 18984734

 

    Legend: Gene, Sites

Title : Site-specific GlcNAcylation of human erythrocyte proteins : potential biomarker(s) for diabetes

Abstract :

1. OBJECTIVE: O-linked N-acetylglucosamine (O-GlcNAc) is upregulated in diabetic tissues and plays a role in insulin resistance and glucose toxicity
2. Here, we investigated the extent of GlcNAcylation on human erythrocyte proteins and compared site-specific GlcNAcylation on erythrocyte proteins from diabetic and normal individuals
3. RESEARCH DESIGN AND METHODS: GlcNAcylated erythrocyte proteins or GlcNAcylated peptides were tagged and selectively enriched by a chemoenzymatic approach and identified by mass spectrometry
4. The enrichment approach was combined with solid-phase chemical derivatization and isotopic labeling to detect O-GlcNAc modification sites and to compare site-specific O-GlcNAc occupancy levels between normal and diabetic erythrocyte proteins
5. RESULTS: The enzymes that catalyze the cycling (addition and removal) of O-GlcNAc were detected in human erythrocytes
6. Twenty-five GlcNAcylated erythrocyte proteins were identified
7. Protein expression levels were compared between diabetic and normal erythrocytes
8. Thirty-five O-GlcNAc sites were reproducibly identified, and their site-specific O-GlcNAc occupancy ratios were calculated
9. CONCLUSIONS: GlcNAcylation is differentially regulated at individual sites on erythrocyte proteins in response to glycemic status
10. These data suggest not only that site-specific O-GlcNAc levels reflect the glycemic status of an individual but also that O-GlcNAc site occupancy on erythrocyte proteins may be eventually useful as a diagnostic tool for the early detection of diabetes

Output (sent_index, trigger, protein, sugar, site):

• 10. occupancy, , proteins, occupancy, -
• 9. GlcNAcylation, , -, -, sites

Output(Part-Of) (sent_index, protein, site):

• 9. proteins, sites

*Output_Site_Fusion* (sent_index, protein, sugar, site):

 

Protein	NCBI ID	SENTENCE INDEX