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Glycosylation, galectins and cellular signaling
Cecile Boscher1, James W Dennis, Ivan R Nabi
1Department of Cellular and Physiological Sciences, Life Sciences Institute, University of British Columbia, Vancouver, BC, Canada.
Current Opinion in Cell Biology
|May 28, 2011
Summary
Glycosylation, a protein modification, creates binding sites for galectins. Increased N-glycan branching enhances galectin interactions, influencing cell functions and evolution.
Area of Science:
- Biochemistry and Molecular Biology
- Cell Biology
- Glycobiology
Background:
- Glycosylation is a key posttranslational modification in the secretory pathway.
- N-glycans, particularly branched structures, bind to galactose-specific lectins called galectins.
- Galectin-glycoprotein interactions are regulated by enzyme expression, sugar supply, and protein sequence.
Purpose of the Study:
- To explore the role of N-glycan branching in galectin binding affinity.
- To understand the evolutionary significance of galectin-glycoprotein interactions.
- To elucidate how galectin lattices regulate cell fate.
Main Methods:
- Analysis of N-glycan structures and their modification by N-acetylglucosaminyltransferases (Mgat genes).
- Investigation of tissue-specific enzyme expression and sugar-nucleotide supply.
- Study of galectin cross-linking of glycoproteins and formation of microdomains.
Main Results:
- Branching of N-glycans by Mgat enzymes increases affinity for galectins.
- Galectin-glycoprotein interactions are influenced by both metabolic and genetic factors.
- Branched N-glycans are a more recent evolutionary development in vertebrates.
Conclusions:
- Galectins act as a code interpreting N-glycan branching and protein site multiplicity.
- Galectin lattices regulate cell surface receptor levels and influence cell fate.
- Further research is needed on galectin regulation and interactions with cellular pathways.
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