Structure of a C-terminal fragment of its Vps53 subunit suggests similarity of Golgi-associated retrograde protein (GARP) complex to a family of tethering complexes.
Publication Type:Journal Article
Source:Proc Natl Acad Sci U S A, Volume 107, Issue 32, p.14176-81 (2010)
Keywords:Carrier Proteins, Crystallography, X-Ray, Endosomes, Multiprotein Complexes, Peptide Fragments, Protein Conformation, Protein Subunits, Protein Transport, Saccharomyces cerevisiae Proteins, trans-Golgi Network
<p>The Golgi-associated retrograde protein (GARP) complex is a membrane-tethering complex that functions in traffic from endosomes to the trans-Golgi network. Here we present the structure of a C-terminal fragment of the Vps53 subunit, important for binding endosome-derived vesicles, at a resolution of 2.9 A. We show that the C terminus consists of two alpha-helical bundles arranged in tandem, and we identify a highly conserved surface patch, which may play a role in vesicle recognition. Mutations of the surface result in defects in membrane traffic. The fold of the Vps53 C terminus is strongly reminiscent of proteins that belong to three other tethering complexes--Dsl1, conserved oligomeric Golgi, and the exocyst--thought to share a common evolutionary origin. Thus, the structure of the Vps53 C terminus suggests that GARP belongs to this family of complexes.</p>