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Bioinformatics Resources for the Study of Glycan-Mediated Protein Interactions
Published on: January 20, 2022
Density-dependent lectin-glycan interactions as a paradigm for conditional regulation by posttranslational
James W Dennis1, C Fred Brewer
1Samuel Lunenfeld Research Institute, Mount Sinai Hospital, and Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada.
Molecular & Cellular Proteomics : MCP
|February 5, 2013
Summary
Glycan compensation in mice shows a feedback system regulating cell surface structures. This discovery offers insights into how cells adapt to environmental changes through glycan density regulation.
Area of Science:
- Biochemistry
- Cell Biology
- Glycobiology
Background:
- Specific Golgi glycosyltransferases are crucial for synthesizing complex carbohydrate structures (glycans).
- Glycans on cell surfaces act as recognition sites for various biological interactions, including those involving lectins.
- Understanding glycan biosynthesis and regulation is key to deciphering cellular responses and adaptations.
Purpose of the Study:
- To investigate glycan compensation mechanisms in vivo.
- To explore the role of Golgi glycosyltransferases in maintaining glycan epitope density.
- To provide evidence for a feedback system regulating cell surface carbohydrates.
Main Methods:
- Utilizing genetically modified mice with null mutations in specific Golgi glycosyltransferases.
- Analyzing the glycan structures on cell surface proteins and related molecules.
- Observing the distribution and density of specific carbohydrate epitopes.
Main Results:
- Mice lacking certain Golgi glycosyltransferases exhibited glycan compensation, with missing epitopes appearing on related structures.
- Repetitive saccharide sequences were identified as functional epitopes recognized by animal lectins.
- These findings represent the first in vivo evidence of a feedback system controlling glycan epitope density.
Conclusions:
- A feedback system exists to maintain and regulate glycan epitope density within cells.
- Lectin-glycan interactions, mediated by the Golgi, allow for cell surface receptor and transporter adaptation to environmental signals.
- Similar density-dependent regulatory mechanisms may apply to other post-translational modification systems.
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