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Models for the functions of Arf GAPs
Michael P East1, Richard A Kahn
1Department of Biochemistry, Emory University School of Medicine, Atlanta, GA 30322-3050, USA. meast@emory.edu
Seminars in Cell & Developmental Biology
|July 20, 2010
Summary
ADP-ribosylation factor GTPase-activating proteins (Arf GAPs) are key regulators of Arf signaling. This review explores their non-canonical roles as effectors, challenging their traditional role as solely signaling terminators.
Area of Science:
- Cellular Biology
- Molecular Biology
- Biochemistry
Background:
- Arf GAPs (ADP-ribosylation factor GTPase-activating proteins) are crucial regulators of Arf (ADP-ribosylation factor) signaling pathways.
- Their primary known function is to stimulate GTP hydrolysis, inactivating Arf proteins and thus terminating signaling.
- Emerging evidence suggests Arf GAPs possess functions beyond signaling termination.
Purpose of the Study:
- To review the non-canonical functions of Arf GAPs.
- To address key questions regarding Arf GAPs' roles as terminators versus effectors.
- To investigate Arf GAPs' involvement in COPI assembly, vesicle fission, and uncoating.
Main Methods:
- Literature review of existing studies on Arf GAPs.
- Analysis of experimental data on Arf GAP functions.
- Synthesis of current understanding of Arf GAP mechanisms.
Main Results:
- Arf GAPs exhibit dual roles as both terminators and effectors in Arf signaling.
- Arf GAPs can positively or negatively influence COPI coat assembly.
- Evidence suggests Arf GAPs participate in vesicle fission and regulate vesicle uncoating processes.
Conclusions:
- Arf GAPs are versatile regulators with functions extending beyond GTPase activity.
- Their non-canonical roles are critical for various cellular processes, including vesicle trafficking.
- Further research is needed to fully elucidate the complex mechanisms of Arf GAPs.
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