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Updated: Jun 24, 2026
12:40
Visualizing Clathrin-mediated Endocytosis of G Protein-coupled Receptors at Single-event Resolution via TIRF Microscopy
Published on: October 20, 2014
Using quantum dots to visualize clathrin associations
Y Ogunkoya1, B M Nickel, V L Gay
1Department of Biological Sciences, College of Sciences, Southern University and A & M College, Baton Rouge, Louisiana, USA.
Summary
Quantum immune-electron microscopy reveals clathrin
Area of Science:
- Cell Biology
- Molecular Biology
- Biochemistry
Background:
- Clathrin-mediated endocytosis is crucial for cellular processes.
- Coated pits and vesicles are key structures in endocytosis.
- Current methods have limitations in precisely tracking cellular organelles.
Purpose of the Study:
- To precisely localize clathrin and its adaptor protein AP-2 in human adrenal cortical cells.
- To investigate the association of clathrin with various vesicle types.
- To clarify the nature of structures identified as coated vesicles by light microscopy.
Main Methods:
- Quantum immune-electron microscopy was employed.
- Human adrenal cortical cell line (SW-13) was used.
- Localization of clathrin and AP-2 with cellular organelles was performed.
Main Results:
- Clathrin was found to associate with multiple vesicle types, including coated vesicles, pits, pentilaminar annular gap junction vesicles, and multivesicular bodies.
- Quantum dot technology provided accurate and specific localization.
- Some structures identified as coated vesicles by light microscopy may be membrane-bound pits.
Conclusions:
- Quantum immune-electron microscopy offers high precision in localizing clathrin and AP-2.
- Clathrin's role extends beyond classic endocytosis to other vesicle types.
- Re-evaluation of structures identified by light microscopy may be necessary.
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