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Published on: March 28, 2014
The structure and function of GGAs, the traffic controllers at the TGN sorting crossroads
Kazuhisa Nakayama1, Soichi Wakatsuki
1Graduate School of Pharmaceutical Sciences, Kyoto University, Yoshida-shimoadachi, Sakyo-ku, Kyoto 606-8501, Japan. kazunaka@pharm.kyoto-u.ac.jp
Cell Structure and Function
|January 28, 2004
Summary
Golgi-localizing, gamma-adaptin ear homology domain, ARF-binding proteins (GGAs) are key adaptors in protein transport. These proteins mediate the movement of cargo, like mannose 6-phosphate receptors, from the Golgi to endosomes via clathrin-coated vesicles.
Area of Science:
- Cell Biology
- Molecular Biology
- Protein Trafficking
Background:
- Golgi-localizing, gamma-adaptin ear homology domain, ARF-binding proteins (GGAs) are monomeric clathrin adaptors conserved across species.
- Recent research has elucidated the localization, domain organization, and structure-function relationships of GGAs.
Purpose of the Study:
- To detail the functional domains of GGAs and their interactions.
- To understand the role of GGAs in cargo protein transport from the trans-Golgi network to endosomes.
Main Methods:
- Analysis of published data on GGA localization and domain organization.
- Investigation of GGA interactions with cargo proteins (e.g., mannose 6-phosphate receptors) and accessory proteins (e.g., ARF, clathrin, Rabaptin-5, gamma-synergin).
Main Results:
- GGAs feature four conserved domains critical for binding cargo, GTPases, clathrin, and accessory proteins.
- GGAs, along with or independently of AP-1, orchestrate the clathrin-mediated transport of cargo proteins from the trans-Golgi network to endosomes.
Conclusions:
- GGAs are essential regulators of selective protein transport within the cell.
- The detailed understanding of GGA function provides insights into intracellular trafficking mechanisms.
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