Related Experiment Video
Updated: May 8, 2025
12:40
Visualizing Clathrin-mediated Endocytosis of G Protein-coupled Receptors at Single-event Resolution via TIRF Microscopy
Published on: October 20, 2014
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Membrane order regulates clathrin-coated pit dynamics but not initiation.
G Aditya Kumar1, Yousef Bagheri2, Manojkumar A Puthenveedu1
1Department of Pharmacology, University of Michigan Medical School, Ann Arbor, MI 48109.
Molecular Biology of the Cell
|April 30, 2025
Summary
Membrane order influences clathrin-coated pit (CCP) dynamics during endocytosis. Cholesterol depletion affects CCP initiation and dynamics, but membrane order primarily regulates CCP lifetimes, not initiation.
Area of Science:
- Cell biology
- Biophysics
Background:
- Clathrin-mediated endocytosis (CME) is crucial for cellular processes.
- Regulation of clathrin-coated pit (CCP) dynamics is key to CME.
- The role of membrane physical properties in CME is underexplored.
Purpose of the Study:
- To investigate the role of membrane order in regulating CCP initiation and dynamics.
- To understand how cholesterol affects CCPs and membrane order.
Main Methods:
- Utilized solvatochromic probes to measure membrane order in live cells.
- Employed total internal reflection fluorescence microscopy for endocytosis visualization.
- Manipulated membrane order via cholesterol depletion and other methods.
Main Results:
- Cholesterol depletion reduced membrane order, decreased CCP initiation, and increased CCP lifetimes.
- In unperturbed cells, membrane order correlated with CCP lifetimes but not initiation.
- Altering membrane order without lipid extraction affected CCP lifetimes but not initiation.
Conclusions:
- Membrane order is a primary regulator of CCP dynamics during endocytosis.
- Cholesterol depletion impacts CCP initiation through mechanisms beyond altering membrane order.
- Membrane physical properties play a significant role in CME regulation.
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