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Updated: Jul 7, 2026
11:11
Determination of Plasma Membrane Partitioning for Peripherally-associated Proteins
Published on: June 15, 2018
Determining protein transport to the plasma membrane
1The Netherlands Cancer Institute, Amsterdam, The Netherlands.
Current Protocols in Cell Biology
|January 30, 2008
Summary
Researchers developed methods to track cell surface proteins. By analyzing post-translational modifications and using enzymatic treatments, they identified proteins reaching the cell surface and those in endocytic pathways.
Area of Science:
- Cell Biology
- Protein Trafficking
- Molecular Biology
Background:
- Integral membrane proteins synthesized in the endoplasmic reticulum are transported to the cell surface.
- Post-translational modifications acquired during Golgi transit serve as markers for cell surface proteins.
Purpose of the Study:
- To establish methods for tracking the appearance of modified proteins at the cell surface.
- To differentiate between cell surface resident proteins and those entering the endocytic pathway.
Main Methods:
- Utilizing enzymatic treatments (sialidase, protease) and biotinylation to identify cell surface proteins.
- Employing temperature-dependent cell treatments (4°C vs. 37°C) to distinguish surface localization from endocytic uptake.
- Analyzing sialic acid content to identify cell surface resident proteins.
Main Results:
- Identified specific enzymatic and chemical treatments to label cell surface proteins.
- Differentiated proteins localized to the cell surface from those internalized via endocytosis based on temperature-dependent enzyme activity.
- Quantified sialic acid modifications to confirm cell surface residency.
Conclusions:
- Developed a robust methodology to track cell surface protein localization.
- The methods allow for the discrimination between cell surface and endocytic pathway proteins.
- This approach aids in understanding protein trafficking and cell surface dynamics.
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