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Published on: November 8, 2006
The auxilin-like phosphoprotein Swa2p is required for clathrin function in yeast
W E Gall1, M A Higginbotham, C Chen
1Department of Biological Sciences, Vanderbilt University, Nashville, Tennessee 37235-1634, USA.
Current Biology : CB
|November 21, 2000
Summary
The yeast SWA2 gene encodes Swa2p, a protein essential for clathrin function in vivo. Swa2p acts as the yeast auxilin ortholog, aiding in clathrin coat disassembly and preventing abnormal clathrin assembly.
Area of Science:
- Cell Biology
- Molecular Biology
Background:
- Clathrin-coated vesicles mediate cargo transport in eukaryotic cells.
- Hsc70 ATPase and auxilin cofactor are required for in vitro clathrin coat removal.
- In vivo roles of auxilin and Hsc70 in clathrin function remain unestablished.
Purpose of the Study:
- To investigate the in vivo function of the yeast SWA2 gene and its encoded protein, Swa2p.
- To determine if Swa2p is involved in clathrin coat dynamics.
Main Methods:
- Cloning and characterization of the SWA2 gene.
- Biochemical assays of Swa2p's interaction with Hsc70 and clathrin.
- Analysis of SWA2 gene disruption phenotypes in Saccharomyces cerevisiae.
- Quantification of membrane-associated clathrin in swa2 mutant strains.
Main Results:
- SWA2 encodes a protein homologous to auxilin with clathrin-binding and Hsc70 ATPase stimulating activities.
- Swa2p contains a TPR domain, suggesting interaction with heat-shock proteins.
- SWA2 disruption leads to phenotypes similar to clathrin mutants, including increased membrane-associated clathrin.
Conclusions:
- Swa2p is a clathrin-binding protein crucial for clathrin function in vivo.
- Swa2p is the yeast ortholog of auxilin, playing a role in clathrin disassembly.
- Swa2p may prevent aberrant clathrin assembly in addition to vesicle uncoating.
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