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Pulse-chase Analysis of N-linked Sugar Chains from Glycoproteins in Mammalian Cells
Published on: April 27, 2010
Glutelin basic subunits have a mammalian mucin-type O-linked disaccharide side chain
T Kishimoto1, M Watanabe, T Mitsui
1Graduate School of Natural Science and Technology, Niigata University, Ikarashi 2-Nocho, Niigata, 950-8101, Japan.
Archives of Biochemistry and Biophysics
|October 8, 1999
Summary
Rice glutelin, a major seed storage protein, contains complex sugar chains. Researchers identified mucin-type O-linked glycosylation and N-linked glycosylation in its carboxy-terminal region.
Area of Science:
- Plant Biochemistry
- Glycobiology
- Food Science
Background:
- Glutelin is a primary storage protein in rice seeds.
- Understanding its post-translational modifications, like glycosylation, is crucial for seed quality and function.
Purpose of the Study:
- To characterize the sugar chains of rice glutelin.
- To investigate the types and locations of glycosylation in glutelin subunits.
Main Methods:
- Glycoprotein staining using Periodic acid-Schiff (PAS) and lectins (Concanavalin A, Peanut Agglutinin).
- Enzymatic and chemical treatments (O-glycanase, NaIO4, NaOH) to analyze sugar chains.
- Pyridylamination followed by 2D-HPLC for sugar chain profiling.
- Amino acid sequencing of specific peptides.
Main Results:
- Rice glutelin basic subunits are glycoproteins.
- A core 1 mucin-type disaccharide (Galβ-1,3GalNAc) is conjugated to glutelin.
- Both N-linked and O-linked glycosylation occur in the carboxy-terminal region of glutelin subunits.
Conclusions:
- Rice glutelin undergoes complex glycosylation, including mucin-type O-glycosylation and N-glycosylation.
- These modifications are localized to the carboxy-terminal region of the subunits.
- Detailed characterization provides insights into rice seed protein structure and function.
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