Authors: | Fath, S.; Mancias, J. D.; Bi, X.; Goldberg, J. |
Article Title: | Structure and organization of coat proteins in the COPII cage |
Abstract: | COPII-coated vesicles export newly synthesized proteins from the endoplasmic reticulum. The COPII coat consists of the Sec23/24-Sar1 complex that selects cargo and the Sec13/31 assembly unit that can polymerize into an octahedral cage and deform the membrane into a bud. Crystallographic analysis of the assembly unit reveals a 28 nm long rod comprising a central α-solenoid dimer capped by two β-propeller domains at each end. We construct a molecular model of the COPII cage by fitting Sec13/31 crystal structures into a recently determined electron microscopy density map. The vertex geometry involves four copies of the Sec31 β-propeller that converge through their axial ends; there is no interdigitation of assembly units of the kind seen in clathrin cages. We also propose that the assembly unit has a central hinge-an arrangement of interlocked α-solenoids-about which it can bend to adapt to cages of variable curvature. © 2007 Elsevier Inc. All rights reserved. |
Keywords: | unclassified drug; protein domain; electron microscopy; animals; cells, cultured; protein assembly; membrane proteins; endoplasmic reticulum; protein synthesis; saccharomyces cerevisiae; geometry; protein transport; crystal structure; models, molecular; crystallography, x-ray; protein structure, tertiary; saccharomyces cerevisiae proteins; protein structure; density; protein structure, secondary; protein derivative; molecular model; protein polymerization; macromolecular substances; nuclear pore complex proteins; clathrin; crystallography; vesicular transport proteins; dimer; coat protein complex ii; coated vesicle; cop-coated vesicles; solenoidea; golgi apparatus; coat protein; sar 1 protein; sec 13 protein; sec 23 protein; sec 24 protein; sec 31 protein; bud |
Journal Title: | Cell |
Volume: | 129 |
Issue: | 7 |
ISSN: | 0092-8674 |
Publisher: | Cell Press |
Date Published: | 2007-06-29 |
Start Page: | 1325 |
End Page: | 1336 |
Language: | English |
DOI: | 10.1016/j.cell.2007.05.036 |
PUBMED: | 17604721 |
PROVIDER: | scopus |
DOI/URL: | |
Notes: | --- - "Cited By (since 1996): 81" - "Export Date: 17 November 2011" - "CODEN: CELLB" - "Source: Scopus" |