2pm7
From Proteopedia
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==Overview== | ==Overview== | ||
| - | COPII-coated vesicles export newly synthesized proteins from the | + | 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. |
==About this Structure== | ==About this Structure== | ||
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[[Category: Fath, S.]] | [[Category: Fath, S.]] | ||
[[Category: Goldberg, J.]] | [[Category: Goldberg, J.]] | ||
| - | [[Category: Mancias, J | + | [[Category: Mancias, J D.]] |
[[Category: alpha solenoid]] | [[Category: alpha solenoid]] | ||
[[Category: beta propeller]] | [[Category: beta propeller]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 18:30:57 2008'' |
Revision as of 16:30, 21 February 2008
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Crystal structure of yeast Sec13/31 edge element of the COPII vesicular coat, selenomethionine version
Overview
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.
About this Structure
2PM7 is a Protein complex structure of sequences from Saccharomyces cerevisiae. Full crystallographic information is available from OCA.
Reference
Structure and organization of coat proteins in the COPII cage., Fath S, Mancias JD, Bi X, Goldberg J, Cell. 2007 Jun 29;129(7):1325-36. PMID:17604721
Page seeded by OCA on Thu Feb 21 18:30:57 2008
