2PM9

Crystal structure of yeast Sec13/31 vertex element of the COPII vesicular coat

Summary for 2PM9

• Entry DOI: 10.2210/pdb2pm9/pdb
• Related: 2PM6 2PM7
• Descriptor: Protein transport protein SEC31, Protein transport protein SEC13 (3 entities in total)
• Functional Keywords: beta propeller, protein transport
• Biological source: Saccharomyces cerevisiae (baker's yeast); More
• Cellular location: Cytoplasmic vesicle, COPII-coated vesicle membrane; Peripheral membrane protein; Cytoplasmic side: P38968 Q04491
• Total number of polymer chains: 2
• Total formula weight: 78842.47

Authors

Goldberg, J.,Fath, S.,Mancias, J.D.,Bi, X. (deposition date: 2007-04-20, release date: 2007-07-03, Last modification date: 2024-04-03)

Primary citation

Fath, S.,Mancias, J.D.,Bi, X.,Goldberg, J.
Structure and Organization of Coat Proteins in the COPII Cage.
Cell(Cambridge,Mass.), 129:1325-1336, 2007

PubMed 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 alpha-solenoid dimer capped by two beta-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 beta-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 alpha-solenoids-about which it can bend to adapt to cages of variable curvature.

PubMed: 17604721
DOI: 10.1016/j.cell.2007.05.036

Experimental method

X-RAY DIFFRACTION (3.3 Å)