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In vivo and in vitro Studies of Adaptor-clathrin Interaction
Published on: January 26, 2011
Nuclear localization of clathrin involves a labile helix outside the trimerization domain
Joel A Ybe1, Sarah N Fontaine, Todd Stone
1Department of Molecular and Cellular Biochemistry, Indiana University, Bloomington, 212 S. Hawthorne Drive, Bloomington, IN 47405, USA. jybe@indiana.edu
FEBS Letters
|November 27, 2012
Summary
Clathrin, a protein crucial for endocytosis, can exist outside its usual trimer form. A specific mutant shows altered distribution and a potential "detrimerization switch" for new functions.
Area of Science:
- Cell Biology
- Protein Structure
- Molecular Mechanisms
Background:
- Clathrin is a key protein in receptor-mediated endocytosis, typically forming a trimer.
- Clathrin's function can extend beyond endocytosis, suggesting alternative structural roles.
- Previous studies examined a clathrin cysteine mutant, hinting at altered properties.
Purpose of the Study:
- To investigate the subcellular localization of a clathrin cysteine mutant.
- To determine the oligomeric state of a specific clathrin mutant (C1573A hub).
- To elucidate the structural basis for potential clathrin detrimerization.
Main Methods:
- Analysis of subcellular distribution of a clathrin cysteine mutant.
- Multi-Angle Light Scattering (MALS) to assess the oligomeric state of the C1573A hub mutant.
- X-ray crystallography of the clathrin trimerization domain.
Main Results:
- The clathrin cysteine mutant exhibited altered subcellular distribution, with some localization to nuclear spaces.
- MALS analysis revealed the C1573A hub exists as a mixture of trimer-like and detrimerized molecules.
- X-ray structure showed reorientation of a helix containing cysteine-1573 in the absence of light chains.
Conclusions:
- Clathrin possesses a detrimerization switch, enabling altered topology.
- This switch suggests clathrin can naturally adopt different structures for novel functions.
- The findings expand our understanding of clathrin's dynamic nature beyond endocytosis.
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