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Updated: May 29, 2026
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Pulse-chase Analysis of N-linked Sugar Chains from Glycoproteins in Mammalian Cells
Published on: April 27, 2010
Mammalian O-mannosylation: unsolved questions of structure/function.
Stephanie H Stalnaker1, Ryan Stuart, Lance Wells
1University of Georgia, Complex Carbohydrate Research Center, Athens, GA, United States.
Current Opinion in Structural Biology
|September 28, 2011
Summary
O-mannosylation, a protein modification pathway, is crucial for cell functions and development. Defects in this pathway lead to congenital muscular dystrophies, highlighting its importance.
Area of Science:
- Biochemistry
- Molecular Biology
- Glycobiology
Background:
- Post-translational modification with glycans increases protein structural and functional diversity.
- O-glycosylation is a significant modification pathway, with O-mannosylation being a recently identified mammalian pathway.
- O-mannose glycans are implicated in critical cellular processes and human diseases.
Purpose of the Study:
- To review the current literature on the mammalian O-mannosylation pathway.
- To highlight the key components and functions of O-mannosylation.
- To identify gaps in understanding structure/function relationships within this pathway.
Main Methods:
- Literature review of existing studies on O-mannosylation.
- Analysis of protein substrates, glycan structures, and enzymes involved.
- Identification of knowledge gaps in structure/function relationships.
Main Results:
- O-mannosylation is vital for viral entry, metastasis, cell adhesion, and neuronal development.
- Mutations in O-mannosylation enzymes cause congenital muscular dystrophies.
- Key protein substrates, glycan structures, and enzymes have been identified.
Conclusions:
- The O-mannosylation pathway is essential for normal physiological processes and development.
- Dysregulation of O-mannosylation is linked to severe human genetic disorders.
- Further research is needed to elucidate the structure/function dynamics of O-mannosylation.
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