1u81

<StructureSection load='1u81' size='340' side='right' caption='[[1u81]], [[NMR_Ensembles_of_Models | 11 NMR models]]' scene=''>

<table><tr><td colspan='2'>[[1u81]] is a 1 chain structure with sequence from [http://en.wikipedia.org/wiki/Human Human]. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1U81 OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1U81 FirstGlance]. <br>

</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=GDP:GUANOSINE-5-DIPHOSPHATE'>GDP</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene></td></tr>

<tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">Arf1 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=9606 HUMAN])</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=1u81 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1u81 OCA], [http://pdbe.org/1u81 PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=1u81 RCSB], [http://www.ebi.ac.uk/pdbsum/1u81 PDBsum]</span></td></tr>

[[http://www.uniprot.org/uniprot/ARF1_HUMAN ARF1_HUMAN]] GTP-binding protein that functions as an allosteric activator of the cholera toxin catalytic subunit, an ADP-ribosyltransferase. Involved in protein trafficking among different compartments. Modulates vesicle budding and uncoating within the Golgi complex. Deactivation induces the redistribution of the entire Golgi complex to the endoplasmic reticulum, suggesting a crucial role in protein trafficking. In its GTP-bound form, its triggers the association with coat proteins with the Golgi membrane. The hydrolysis of ARF1-bound GTP, which is mediated by ARFGAPs proteins, is required for dissociation of coat proteins from Golgi membranes and vesicles.

<scriptWhenChecked>select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/u8/1u81_consurf.spt"</scriptWhenChecked>

</jmol>, as determined by [http://consurfdb.tau.ac.il/ ConSurfDB]. You may read the [[Conservation%2C_Evolutionary|explanation]] of the method and the full data available from [http://bental.tau.ac.il/new_ConSurfDB/chain_selection.php?pdb_ID=2ata ConSurf].

<div style="background-color:#fffaf0;">

== Publication Abstract from PubMed ==

Conformational changes associated with nucleotide exchange or truncation of the N-terminal alpha-helix of human Arf1 have been investigated by using forms of easily acquired NMR data, including residual dipolar couplings and amide proton exchange rates. ADP-ribosylation factors (Arfs) are 21-kDa GTPases that regulate aspects of membrane traffic in all eukaryotic cells. An essential component of the biological actions of Arfs is their ability to reversibly bind to membranes, a process that involves exposure of the myristoylated N-terminal amphipathic alpha-helix upon activation and GTP binding. Deletion of this helix results in a protein, termed Delta17Arf1, that has a reduced affinity for GDP and the ability to bind GTP in the absence of lipids or detergents. Previous studies, comparing crystal structures for Arf1.GDP and Delta17Arf1.GTP, identified several regions of structural variation and suggested that these be associated with nucleotide exchange rather than removal of the N-terminal helix. However, separation of conformational changes because of nucleotide binding and N-terminal truncation cannot be addressed in comparing these structures, because both the bound nucleotide and the N terminus differ. Resolving the two effects is important as any structural changes involving the N terminus may represent membrane-mediated conformational adjustments that precede GTP binding. Results from NMR experiments presented here on Arf1.GDP and Delta17Arf1.GDP in solution reveal substantial structural differences that can only be associated with N-terminal truncation.

Conformational changes in human Arf1 on nucleotide exchange and deletion of membrane-binding elements.,Seidel RD 3rd, Amor JC, Kahn RA, Prestegard JH J Biol Chem. 2004 Nov 12;279(46):48307-18. Epub 2004 Aug 12. PMID:15308674<ref>PMID:15308674</ref>

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

</div>

<div class="pdbe-citations 1u81" style="background-color:#fffaf0;"></div>

== References ==

<references/>

[[Category: Human]]

[[Category: Amor, J C]]

[[Category: Kahn, R A]]

[[Category: Prestegard, J H]]

[[Category: Seidel, R D]]

[[Category: Arf1]]

[[Category: Rdc refinement]]