1hvv

<table><tr><td colspan='2'>[[1hvv]] is a 4 chain structure. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1HVV OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1HVV FirstGlance]. <br>

</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=TAR:D(-)-TARTARIC+ACID'>TAR</scene></td></tr>

<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1hvv FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1hvv OCA], [http://pdbe.org/1hvv PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=1hvv RCSB], [http://www.ebi.ac.uk/pdbsum/1hvv PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=1hvv ProSAT]</span></td></tr>

[[http://www.uniprot.org/uniprot/STX1A_RAT STX1A_RAT]] Potentially involved in docking of synaptic vesicles at presynaptic active zones. May play a critical role in neurotransmitter exocytosis. May mediate Ca(2+)-regulation of exocytosis acrosomal reaction in sperm.

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== Publication Abstract from PubMed ==

Intracellular membrane fusion requires SNARE proteins found on the vesicle and target membranes. SNAREs associate by formation of a parallel four-helix bundle, and it has been suggested that formation of this complex promotes membrane fusion. The membrane proximal region of the cytoplasmic domain of the SNARE syntaxin 1A, designated H3, contributes one of the four helices to the SNARE complex. In the crystal structure of syntaxin 1A H3, four molecules associate as a homotetramer composed of two pairs of parallel helices that are anti-parallel to each other. The H3 oligomer observed in the crystals is also found in solution, as assessed by gel filtration and chemical cross-linking studies. The crystal structure reveals that the highly conserved Phe-216 packs against conserved Gln-226 residues present on the anti-parallel pair of helices. Modeling indicates that Phe-216 prevents parallel tetramer formation. Mutation of Phe-216 to Leu appears to allow formation of parallel tetramers, whereas mutation to Ala destabilizes the protein. These results indicate that Phe-216 has a role in preventing formation of stable parallel helical bundles, thus favoring the interaction of the H3 region of syntaxin 1a with other proteins involved in membrane fusion.

Self-association of the H3 region of syntaxin 1A. Implications for intermediates in SNARE complex assembly.,Misura KM, Scheller RH, Weis WI J Biol Chem. 2001 Apr 20;276(16):13273-82. Epub 2000 Dec 15. PMID:11118447<ref>PMID:11118447</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>

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<div class="pdbe-citations 1hvv" style="background-color:#fffaf0;"></div>

*[[Syntaxin|Syntaxin]]

[[Category: Misura, K M.S]]

[[Category: Scheller, R H]]

[[Category: Weis, W I]]

[[Category: Alpha-helix]]

[[Category: Homotetramer]]