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Updated: Aug 12, 2026
10:17
Pulse-chase Analysis of N-linked Sugar Chains from Glycoproteins in Mammalian Cells
Published on: April 28, 2010
Oligosaccharyl transferase: gatekeeper to the secretory pathway
Robert E Dempski1, Barbara Imperiali
1Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA.
Current Opinion in Chemical Biology
|December 10, 2002
Summary
Oligosaccharyl transferase (OST) is a conserved enzyme crucial for N-linked glycoprotein biosynthesis in the endoplasmic reticulum. Ongoing research is revealing its complex interactions with other proteins, clarifying its role in the secretory pathway.
Area of Science:
- Biochemistry
- Molecular Biology
- Cell Biology
Background:
- Oligosaccharyl transferase (OST) is a key enzyme complex.
- It catalyzes the initial, conserved step in N-linked glycoprotein biosynthesis.
- OST functions as a critical 'gatekeeper' for the endoplasmic reticulum secretory pathway.
Purpose of the Study:
- To elucidate the intricate functions of OST.
- To understand the relationship between OST and other endoplasmic reticulum proteins.
- To further unravel the complexities of protein processing in the ER.
Main Methods:
- Identification of novel proteins associated with OST.
- Analysis of protein-protein interactions within the ER lumen.
- Biochemical and molecular characterization of the OST complex.
Main Results:
- An increasing number of proteins interacting with OST have been identified.
- These findings highlight the complex machinery surrounding OST.
- The study sheds light on the enzyme's role beyond initial catalysis.
Conclusions:
- OST is a central component of a larger protein-processing network in the ER.
- Understanding OST's interactome is crucial for comprehending glycoprotein biosynthesis and ER function.
- Further research will continue to unravel the intricacies of this essential enzyme complex.
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