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Pulse-chase Analysis of N-linked Sugar Chains from Glycoproteins in Mammalian Cells
Published on: April 27, 2010
Snail1 is stabilized by O-GlcNAc modification in hyperglycaemic condition
Sang Yoon Park1, Hyun Sil Kim, Nam Hee Kim
1Department of Biology, Yonsei University, Seodaemun-gu, Seoul, Korea.
The EMBO Journal
|October 21, 2010
Summary
O-GlcNAc modification stabilizes Snail1, a key regulator of epithelial-mesenchymal transition (EMT), by blocking its degradation. This links cellular glucose levels to EMT control via Snail1 regulation.
Area of Science:
- Biochemistry
- Cell Biology
- Molecular Biology
Background:
- Protein O-phosphorylation and O-GlcNAc modification are reciprocal regulatory mechanisms.
- Snail1, a repressor of E-cadherin, is a key regulator of the epithelial-mesenchymal transition (EMT).
- O-phosphorylation of Snail1 by GSK-3β promotes its proteasomal degradation.
Purpose of the Study:
- To investigate the role of O-GlcNAc modification at serine112 on Snail1 stability and function.
- To elucidate the molecular link between cellular glucose metabolism and EMT regulation.
- To understand how reciprocal O-phosphorylation and O-GlcNAc modification of Snail1 control E-cadherin expression.
Main Methods:
- Western blotting to detect protein modifications and levels.
- Immunoprecipitation assays to study protein interactions.
- Quantitative real-time PCR to measure E-cadherin mRNA expression.
- Cellular assays to assess EMT progression.
Main Results:
- O-GlcNAc modification at serine112 stabilizes Snail1 by suppressing O-phosphorylation-mediated degradation.
- Stabilized Snail1 enhances its repressor function, leading to decreased E-cadherin mRNA expression.
- Hyperglycemic conditions increase O-GlcNAc modification, promoting Snail1-mediated EMT initiation.
Conclusions:
- Reciprocal O-phosphorylation and O-GlcNAc modification of Snail1 represent a novel regulatory mechanism.
- This dynamic modification of Snail1 provides a molecular link between glucose metabolism and EMT.
- Targeting this regulatory axis could offer therapeutic strategies for EMT-related diseases.
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