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Updated: Jun 21, 2025

12:40
Visualizing Clathrin-mediated Endocytosis of G Protein-coupled Receptors at Single-event Resolution via TIRF Microscopy
Published on: October 20, 2014
80.2K
CCDC32 stabilizes clathrin-coated pits and drives their invagination
Biorxiv : the Preprint Server for Biology
|July 9, 2024
Summary
CCDC32 is a novel protein crucial for clathrin-mediated endocytosis (CME) by stabilizing clathrin-coated pits. Mutations in CCDC32 impair AP2 binding, linking it to cardio-facio-neuro-developmental syndrome (CFNDS).
Area of Science:
- Cell biology
- Molecular biology
- Genetics
Background:
- Clathrin-mediated endocytosis (CME) is vital for cellular homeostasis.
- Over 50 accessory proteins are known, but the mechanism of clathrin-coated pit (CCP) invagination is unclear.
Purpose of the Study:
- To investigate the function of the poorly characterized endocytic accessory protein CCDC32 in CME.
- To elucidate the role of CCDC32 in CCP stabilization and invagination.
Main Methods:
- Quantitative live cell imaging.
- siRNA-mediated knockdown of CCDC32.
- In vitro and cellular binding assays with AP2 complexes.
- Analysis of CCDC32 mutations.
Main Results:
- CCDC32 knockdown causes accumulation of unstable, flat clathrin assemblies.
- CCDC32 interacts with the AP2 complex.
- A specific region (aa78-98) of CCDC32 is essential for AP2 binding and CME function.
- Clinical mutations in CCDC32 lacking this region correlate with CFNDS.
Conclusions:
- CCDC32 is a novel accessory protein essential for stabilizing CCPs and facilitating their invagination during CME.
- CCDC32's interaction with AP2 is critical for its function.
- Impaired CCDC32-AP2 interaction due to mutations may contribute to cardio-facio-neuro-developmental syndrome (CFNDS).
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