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Published on: September 9, 2017
ArfGAP1 interacts with coat proteins through tryptophan-based motifs
Moran Rawet1, Sharon Levi-Tal, Edith Szafer-Glusman
1Department of Biology, Technion-Israel Institute of Technology, Haifa 32000, Israel.
Biochemical and Biophysical Research Communications
|March 10, 2010
Summary
ArfGAP1
Area of Science:
- Cell Biology
- Molecular Biology
- Protein Interactions
Background:
- ArfGAP1 is a GTPase-activating protein that controls vesicular transport via the COPI system.
- Its structure includes a catalytic domain, lipid-packing sensors (ALPS motifs), and a carboxy terminus of unclear function.
- The carboxy terminus contains motifs resembling those that bind clathrin adaptors.
Purpose of the Study:
- To investigate the function of the carboxy terminus of ArfGAP1.
- To identify interactions between ArfGAP1 and clathrin adaptors or coatomers.
- To elucidate the role of ArfGAP1 in COPI-mediated vesicular traffic.
Main Methods:
- Pull-down assays using GST-fused peptides of rat ArfGAP1.
- Mutagenesis and peptide competition experiments.
- Reporter fusion assays to assess in vivo interactions.
Main Results:
- A WETF sequence in ArfGAP1 interacted with clathrin adaptors AP1 and AP2.
- A key coatomer-binding determinant was identified in the extreme carboxy terminus ((405)AADEGWDNQNW).
- This determinant is essential for coatomer binding to full-length ArfGAP1, mediated by the delta-subunit.
Conclusions:
- The carboxy terminus of ArfGAP1 plays a crucial role in coatomer interaction.
- ArfGAP1 exhibits mechanistic differences compared to other COPI-associated ArfGAPs.
- These findings reveal novel aspects of ArfGAP1's function in vesicular transport regulation.
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