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Oligopeptide Competition Assay for Phosphorylation Site Determination
Published on: May 18, 2017
O-GlcNAc modification: why so intimately associated with phosphorylation?
Suresh Mishra1, Sudharsana R Ande, Neil W Salter
1Department of Internal Medicine University of Manitoba, Winnipeg, Canada. mishra@cc.umanitoba.ca.
Cell Communication and Signaling : CCS
|January 13, 2011
Summary
Protein O-GlcNAc modification, a key regulator, interacts with phosphorylation. We propose phosphorylation, including tyrosine phosphorylation, is essential for O-GlcNAc regulation and its interplay with other modifications.
Area of Science:
- Biochemistry
- Molecular Biology
- Cellular Signaling
Background:
- Post-translational modification by O-GlcNAc is a crucial regulatory mechanism.
- O-GlcNAc modification and serine/threonine phosphorylation extensively interplay in proteins.
- The precise regulatory mechanisms governing O-GlcNAc modification and its crosstalk with phosphorylation remain unclear.
Purpose of the Study:
- To investigate the regulatory mechanisms of O-GlcNAc modification.
- To elucidate the interplay between O-GlcNAc modification and protein phosphorylation.
- To test the hypothesis that phosphorylation is a prerequisite for O-GlcNAc modification.
Main Methods:
- Mass spectrometry-based mapping of O-GlcNAc modification sites.
- Analysis of O-GlcNAc and phosphorylation patterns in proteins.
- Bioinformatic analysis of modification site prevalence.
Main Results:
- Nearly all identified O-GlcNAc modified proteins are also phosphorylated.
- Tyrosine phosphorylation is significantly more prevalent (~68%) in O-GlcNAc modified proteins than typically observed (~2%).
- This suggests a potential role for tyrosine phosphorylation in the O-GlcNAc-phosphorylation crosstalk.
Conclusions:
- Phosphorylation may be a prerequisite for O-GlcNAc modification.
- The interplay between O-GlcNAc and phosphorylation extends beyond serine/threonine to include tyrosine phosphorylation.
- This hypothesis offers insights into O-GlcNAc regulation, its crosstalk with phosphorylation, and tyrosine kinase signaling.
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