Related Experiment Video
Updated: Aug 11, 2026
07:54
Cholesterol Efflux Assay
Published on: March 6, 2012
Acute cholesterol depletion inhibits clathrin-coated pit budding
A Subtil1, I Gaidarov, K Kobylarz
1Department of Biochemistry, Weill Graduate School of Medical Sciences of Cornell University, New York, NY 10021, USA.
Summary
Cell membrane cholesterol is crucial for clathrin-coated pit endocytosis. Cholesterol depletion prevents coated pits from detaching, inhibiting the internalization of important molecules like transferrin receptor.
Area of Science:
- Cell biology
- Membrane trafficking
- Endocytosis
Background:
- Clathrin-coated pit endocytosis is a key cellular process for internalizing macromolecules.
- Membrane lipid composition and organization are thought to regulate membrane trafficking.
Purpose of the Study:
- To investigate the role of membrane cholesterol in clathrin-coated pit endocytosis.
- To determine how cholesterol affects the internalization of transferrin receptor.
Main Methods:
- Acute cholesterol depletion using beta-methyl-cyclodextrin.
- Live-cell imaging with a green fluorescent protein-clathrin conjugate.
- Ultrastructural analysis of coated pits.
Main Results:
- Cholesterol depletion reduced transferrin receptor internalization by over 85%.
- Coated pits failed to detach from the plasma membrane after cholesterol depletion.
- Ultrastructural studies showed an accumulation of flat-coated membranes and fewer deep-coated pits.
Conclusions:
- Membrane cholesterol is critical for clathrin-coated pit internalization.
- Cholesterol is required for the detachment of coated pits from the plasma membrane.
- Clathrin cannot induce membrane curvature in cholesterol-depleted membranes.
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