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09:54
Identification and Characterization of Protein Glycosylation using Specific Endo- and Exoglycosidases
Published on: December 26, 2011
Global identification of O-GlcNAc-modified proteins
Animesh Nandi1, Robert Sprung, Deb K Barma
1Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, Texas 75390-9038, USA.
Analytical Chemistry
|January 18, 2006
Summary
Researchers identified O-linked N-acetylglucosamine (O-GlcNAc) modified proteins using a novel TAS method. This approach revealed diverse protein functions regulated by O-GlcNAc, impacting multiple cellular pathways.
Area of Science:
- Proteomics
- Post-translational Modifications
- Cellular Biology
Background:
- O-linked N-acetylglucosamine (O-GlcNAc) is a widespread posttranslational modification on serine/threonine residues.
- The full subproteome and functional roles of O-GlcNAc modification are not well understood.
Purpose of the Study:
- To globally identify O-GlcNAc-modified proteins.
- To explore the functional implications of O-GlcNAc modification.
Main Methods:
- Application of the tagging-via-substrate (TAS) approach.
- Metabolic labeling using an O-GlcNAc azide analogue.
- Chemoselective conjugation for protein detection and enrichment.
- Proteomics analysis and reciprocal immunoprecipitation for validation.
Main Results:
- Identification of 199 putative O-GlcNAc-modified proteins in HeLa cells.
- Confirmation of 23 O-GlcNAc-modified proteins via reciprocal immunoprecipitation.
- Functional classification revealed diverse roles for modified proteins.
Conclusions:
- The TAS approach is effective for global O-GlcNAc proteomics.
- O-GlcNAc modification regulates a wide array of cellular proteins and pathways.
- O-GlcNAc signaling plays a significant role in cellular regulation.
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