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Is clathrin a membrane fission protein?
Ling-Gang Wu1, Lisi Wei1, Michael M Kozlov2
1National Institute of Neurological Disorders and Stroke, 35 Convent Dr., Bldg 35, Bethesda, MD 20892, USA.
Trends in Cell Biology
|April 20, 2025
Summary
Membrane fission, crucial for cell processes, may be mediated by clathrin proteins. These proteins can constrict the neck of Ω-shaped membrane profiles, impacting endocytosis.
Area of Science:
- Cell Biology
- Molecular Biology
- Membrane Dynamics
Background:
- Membrane fission is essential for cellular functions like endocytosis and vesicle trafficking.
- Traditionally, helix-forming proteins were believed to drive membrane neck constriction.
- The role of pit-coating proteins in membrane fission remained less understood.
Purpose of the Study:
- To investigate the potential role of membrane pit-coating proteins, specifically clathrin, in mediating membrane fission.
- To explore how clathrin polymerization might contribute to the constriction of Ω-shaped membrane profiles.
- To re-evaluate endocytic modes previously considered clathrin-independent.
Main Methods:
- Analysis of Ω-shaped membrane profiles.
- Investigating protein polymerization dynamics at membrane necks.
- Utilizing advanced microscopy and biochemical assays (details not provided in abstract).
Main Results:
- Evidence suggests clathrin polymerization can occur on Ω-shaped membrane profiles.
- Clathrin polymerization appears to generate neck constriction, a key step in membrane fission.
- This mechanism provides an alternative pathway for fission, potentially explaining previously observed clathrin-independent endocytosis.
Conclusions:
- Clathrin, a membrane pit-coating protein, may actively participate in membrane fission.
- Clathrin-mediated neck constriction offers a novel understanding of endocytic mechanisms.
- Reclassifying certain endocytic events as potentially clathrin-dependent.
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