1pcx
From Proteopedia
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Crystal structure of the COPII coat subunit, Sec24, complexed with a peptide from the SNARE protein Bet1
Overview
The COPII coat buds transport vesicles from the endoplasmic reticulum that incorporate cargo and SNARE molecules. Here, we show that recognition of the ER-Golgi SNAREs Bet1, Sed5, and Sec22 occurs through three binding sites on the Sec23/24 subcomplex of yeast COPII. The A site binds to the YNNSNPF motif of Sed5. The B site binds to Lxx-L/M-E sequences present in both the Bet1 and Sed5 molecules, as well as to the DxE cargo-sorting signal. A third, spatially distinct site binds to Sec22. COPII selects the free v-SNARE form of Bet1 because the LxxLE sequence is sequestered in the four-helix bundle of the v-/t-SNARE complex. COPII favors Sed5 within the Sed5/Bos1/Sec22 t-SNARE complex because t-SNARE assembly removes autoinhibitory contacts to expose the YNNSNPF motif. The COPII coat seems to be a specific conductor of the fusogenic forms of these SNAREs, suggesting how vesicle fusion specificity may be programmed during budding.
About this Structure
1PCX is a Protein complex structure of sequences from Saccharomyces cerevisiae with as ligand. Full crystallographic information is available from OCA.
Reference
SNARE selectivity of the COPII coat., Mossessova E, Bickford LC, Goldberg J, Cell. 2003 Aug 22;114(4):483-95. PMID:12941276
Page seeded by OCA on Thu Feb 21 14:27:31 2008
