1m2v
Crystal Structure of the yeast Sec23/24 heterodimer
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OverviewOverview
COPII-coated vesicles form on the endoplasmic reticulum by the stepwise, recruitment of three cytosolic components: Sar1-GTP to initiate coat, formation, Sec23/24 heterodimer to select SNARE and cargo molecules, and, Sec13/31 to induce coat polymerization and membrane deformation., Crystallographic analysis of the Saccharomyces cerevisiae Sec23/24-Sar1, complex reveals a bow-tie-shaped structure, 15 nm long, with a, membrane-proximal surface that is concave and positively charged to, conform to the size and acidic-phospholipid composition of the COPII, vesicle. Sec23 and Sar1 form a continuous surface stabilized by a, non-hydrolysable GTP analogue, and Sar1 has rearranged from the GDP, conformation to expose amino-terminal residues that will probably embed in, the bilayer. The GTPase-activating protein (GAP) activity of Sec23, involves an arginine side chain inserted into the Sar1 active site. These, observations establish the structural basis for GTP-dependent recruitment, of a vesicular coat complex, and for uncoating through coat-controlled GTP, hydrolysis.
About this StructureAbout this Structure
1M2V is a Protein complex structure of sequences from Saccharomyces cerevisiae with ZN as ligand. Full crystallographic information is available from OCA.
ReferenceReference
Structure of the Sec23/24-Sar1 pre-budding complex of the COPII vesicle coat., Bi X, Corpina RA, Goldberg J, Nature. 2002 Sep 19;419(6904):271-7. PMID:12239560
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