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Characterization of Glycoproteins with the Immunoglobulin Fold by X-Ray Crystallography and Biophysical Techniques
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Enterocyte glycosylation is responsive to changes in extracellular conditions: implications for membrane functions
Dayoung Park1, Gege Xu1, Mariana Barboza1,2
1Department of Chemistry.
Glycobiology
|May 10, 2017
Summary
Intestinal epithelial cells alter their cell surface sugars in response to diet and microbes. Increased high mannose glycans, a key change, negatively impacts gut barrier function and cell interactions.
Area of Science:
- Cell Biology
- Glycobiology
- Gastroenterology
Background:
- Intestinal epithelial cells maintain homeostasis despite dynamic luminal changes.
- Their surface glycans are densely glycosylated, susceptible to environmental alterations.
- Molecular details and consequences of conditional glycan changes remain unclear.
Purpose of the Study:
- To investigate the sensitivity of intestinal epithelial N-glycosylation to environmental factors.
- To understand the functional consequences of altered glycan expression.
Main Methods:
- Utilized Caco-2 and HT-29 cell lines.
- Applied global LC-MS glycomic and statistical analyses.
- Used a mannosidase inhibitor to intensify high mannose glycosylation.
Main Results:
- Glycan expression changes were systematic and condition-dependent.
- Short chain fatty acids increased fucosylation; acidification promoted hypersialylation.
- Elevated extracellular fructose, galactose, and glutamine increased high mannose glycans.
Conclusions:
- High mannose glycosylation upregulation detrimentally affects intestinal epithelial functions.
- Altered glycosylation impacts permeability, host-microbe associations, and membrane protein activity.
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