Dataset Information

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

ABSTRACT:

Objective

O-linked N-acetylglucosamine (O-GlcNAc) is upregulated in diabetic tissues and plays a role in insulin resistance and glucose toxicity. Here, we investigated the extent of GlcNAcylation on human erythrocyte proteins and compared site-specific GlcNAcylation on erythrocyte proteins from diabetic and normal individuals.

Research design and methods

GlcNAcylated erythrocyte proteins or GlcNAcylated peptides were tagged and selectively enriched by a chemoenzymatic approach and identified by mass spectrometry. 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.

Results

The enzymes that catalyze the cycling (addition and removal) of O-GlcNAc were detected in human erythrocytes. Twenty-five GlcNAcylated erythrocyte proteins were identified. Protein expression levels were compared between diabetic and normal erythrocytes. Thirty-five O-GlcNAc sites were reproducibly identified, and their site-specific O-GlcNAc occupancy ratios were calculated.

Conclusions

GlcNAcylation is differentially regulated at individual sites on erythrocyte proteins in response to glycemic status. 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.

SUBMITTER: Wang Z

PROVIDER: S-EPMC2628603 | biostudies-literature | 2009 Feb

REPOSITORIES: biostudies-literature

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Publications

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

Wang Zihao Z Park Kyoungsook K Comer Frank F Hsieh-Wilson Linda C LC Saudek Christopher D CD Hart Gerald W GW

Diabetes 20081104 2

<h4>Objective</h4>O-linked N-acetylglucosamine (O-GlcNAc) is upregulated in diabetic tissues and plays a role in insulin resistance and glucose toxicity. Here, we investigated the extent of GlcNAcylation on human erythrocyte proteins and compared site-specific GlcNAcylation on erythrocyte proteins from diabetic and normal individuals.<h4>Research design and methods</h4>GlcNAcylated erythrocyte proteins or GlcNAcylated peptides were tagged and selectively enriched by a chemoenzymatic approach and ...[more]

PMID: 18984734

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Dataset Information

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

Objective

Research design and methods

Results

Conclusions

Publications

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

Similar Datasets

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