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Updated: Nov 1, 2025
12:40
Visualizing Clathrin-mediated Endocytosis of G Protein-coupled Receptors at Single-event Resolution via TIRF Microscopy
Published on: October 20, 2014
80.5K
CALM supports clathrin-coated vesicle completion upon membrane tension increase
Nathan M Willy1, Federico Colombo2, Scott Huber1
1Department of Physics, The Ohio State University, Columbus, OH 43210.
Summary
Clathrin assembly lymphoid myeloid leukemia protein (CALM) is crucial for clathrin-mediated endocytosis. This study reveals CALM
Area of Science:
- Cell Biology
- Molecular Biology
Background:
- Clathrin-coated vesicles (CCVs) mediate essential cellular transport processes.
- Key components include clathrin and adaptors like CALM and AP2.
- Studying CALM dynamics has been challenging due to overexpression toxicity.
Purpose of the Study:
- To investigate the recruitment dynamics of CALM during CCV formation.
- To overcome limitations of previous overexpression studies.
Main Methods:
- Utilized knock-in gene editing to create a fluorescent CALM reporter.
- Employed advanced live-cell microscopy to observe CALM recruitment in real-time.
- Quantified CALM levels and correlated with vesicle formation.
Main Results:
- CALM promotes CCV completion in response to increased membrane tension.
- Vesicle formation efficiency correlates with the amount of CALM present.
- Demonstrated CALM's role in CCV dynamics without toxicity.
Conclusions:
- CALM's function is concentration-dependent, influencing CCV completion.
- Tissue-specific expression of adaptors like CALM suggests tissue-specific endocytic efficiency.
- Explains CALM's essential role in embryogenesis and red blood cell development.
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