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PubMed · 14690497

Gamma-COP appendage domain - structure and function.

Peter J Watson·Gabriella Frigerio·Brett M Collins·Rainer Duden·David J Owen
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Abstract

COPI-coated vesicles mediate retrograde transport from the Golgi back to the ER and intra-Golgi transport. The cytosolic precursor of the COPI coat, the heptameric coatomer complex, can be thought of as composed of two subcomplexes. The first consists of the beta-, gamma-, delta- and zeta-COP subunits which are distantly homologous to AP clathrin adaptor subunits. The second consists of the alpha-, beta'- and epsilon-COP subunits. Here, we present the structure of the appendage domain of gamma-COP and show that it has a similar overall fold as the alpha-appendage of AP2. Again, like the alpha-appendage the gamma-COP appendage possesses a single protein/protein interaction site on its platform subdomain. We show that in yeast this site binds to the ARFGAP Glo3p, and in mammalian gamma-COP this site binds to a Glo3p orthologue, ARFGAP2. On the basis of mutations in the yeast homologue of gamma-COP, Sec21p, a second binding site is proposed to exist on the gamma-COP appendage that interacts with the alpha,beta',epsilon COPI subcomplex.

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ADP-Ribosylation FactorsAmino Acid SequenceAnimalsBinding SitesCoat Protein Complex ICrystallography, X-RayFungal ProteinsGTPase-Activating ProteinsHumansMacromolecular SubstancesModels, MolecularMolecular Sequence DataProtein BindingProtein ConformationProtein FoldingProtein Structure, TertiaryProtein SubunitsRatsSequence AlignmentTransport VesiclesJournal ArticleResearch Support, Non-U.S. Gov't

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Peter J Watson, Gabriella Frigerio, Brett M Collins, Rainer Duden, David J Owen. 2004. Gamma-COP appendage domain - structure and function.. https://doi.org/10.1111/j.1600-0854.2004.00158.x

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