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.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
