Related Experiment Video
Updated: Aug 21, 2025
08:51
Profiling of Permethylated Mucin O-glycans Using Matrix-assisted Laser Desorption/Ionization Time-of-flight Mass Spectrometry
Published on: June 20, 2025
253
A Golgi oxygen sensor controls intestinal mucin glycosylation
1Department of Medical Biochemistry and Cell Biology, University of Gothenburg, Gothenburg, Sweden.
The EMBO Journal
|November 16, 2022
Summary
Researchers found that the Golgi enzyme quiescin sulfhydryl oxidase 1 (QSOX1) regulates intestinal mucus by controlling mucin sialylation, impacting mucus-bacterial balance.
Area of Science:
- Cell Biology
- Glycobiology
- Gastroenterology
Background:
- Intestinal mucin glycosylation is crucial for maintaining the mucus barrier and its homeostasis with gut bacteria.
- Alterations in mucin glycosylation are associated with various gastrointestinal diseases.
Purpose of the Study:
- To identify novel regulators of intestinal mucin glycosylation.
- To elucidate the role of specific enzymes in controlling mucin structure and function.
Main Methods:
- Investigated the function of Golgi-resident enzymes in mucin modification.
- Utilized biochemical assays and cellular models to assess enzyme activity and impact on mucin sialylation.
Main Results:
- Identified quiescin sulfhydryl oxidase 1 (QSOX1) as a key enzyme in the Golgi apparatus.
- Demonstrated that QSOX1 controls the sialylation of intestinal mucins.
- Established QSOX1 as a novel regulator of mucus properties.
Conclusions:
- QSOX1 plays a significant role in regulating intestinal mucin sialylation.
- The findings provide new insights into the mechanisms governing mucus barrier integrity.
- QSOX1 emerges as a potential therapeutic target for diseases involving altered mucin glycosylation.
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