|
|
| (3 intermediate revisions not shown.) |
| Line 1: |
Line 1: |
| | + | |
| | ==Arf1(Delta1-17)in complex with BRAG2 Sec7-PH domain== | | ==Arf1(Delta1-17)in complex with BRAG2 Sec7-PH domain== |
| - | <StructureSection load='4c0a' size='340' side='right' caption='[[4c0a]], [[Resolution|resolution]] 3.30Å' scene=''> | + | <StructureSection load='4c0a' size='340' side='right'caption='[[4c0a]], [[Resolution|resolution]] 3.30Å' scene=''> |
| | == Structural highlights == | | == Structural highlights == |
| - | <table><tr><td colspan='2'>[[4c0a]] is a 8 chain structure with sequence from [http://en.wikipedia.org/wiki/Bos_taurus Bos taurus] and [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4C0A OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=4C0A FirstGlance]. <br> | + | <table><tr><td colspan='2'>[[4c0a]] is a 8 chain structure with sequence from [https://en.wikipedia.org/wiki/Bos_taurus Bos taurus] and [https://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4C0A OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4C0A FirstGlance]. <br> |
| - | </td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=G3D:GUANOSINE-3-MONOPHOSPHATE-5-DIPHOSPHATE'>G3D</scene></td></tr> | + | </td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 3.3Å</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=4c0a FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4c0a OCA], [http://www.rcsb.org/pdb/explore.do?structureId=4c0a RCSB], [http://www.ebi.ac.uk/pdbsum/4c0a PDBsum]</span></td></tr> | + | <tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=G3D:GUANOSINE-3-MONOPHOSPHATE-5-DIPHOSPHATE'>G3D</scene></td></tr> |
| | + | <tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=4c0a FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4c0a OCA], [https://pdbe.org/4c0a PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4c0a RCSB], [https://www.ebi.ac.uk/pdbsum/4c0a PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4c0a ProSAT]</span></td></tr> |
| | </table> | | </table> |
| | == Function == | | == Function == |
| - | [[http://www.uniprot.org/uniprot/ARF1_BOVIN ARF1_BOVIN]] 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. | + | [https://www.uniprot.org/uniprot/IQEC1_HUMAN IQEC1_HUMAN] In addition to accelerate GTP gamma S binding by ARFs of all three classes, it appears to function preferentially as a guanine nucleotide exchange protein for ARF6, mediating internalisation of beta-1 integrin.<ref>PMID:11226253</ref> <ref>PMID:16461286</ref> |
| | <div style="background-color:#fffaf0;"> | | <div style="background-color:#fffaf0;"> |
| | == Publication Abstract from PubMed == | | == Publication Abstract from PubMed == |
| Line 16: |
Line 18: |
| | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> |
| | </div> | | </div> |
| | + | <div class="pdbe-citations 4c0a" style="background-color:#fffaf0;"></div> |
| | == References == | | == References == |
| | <references/> | | <references/> |
| Line 22: |
Line 25: |
| | [[Category: Bos taurus]] | | [[Category: Bos taurus]] |
| | [[Category: Homo sapiens]] | | [[Category: Homo sapiens]] |
| - | [[Category: Aizel, K]] | + | [[Category: Large Structures]] |
| - | [[Category: Biou, V]] | + | [[Category: Aizel K]] |
| - | [[Category: Campanacci, V]] | + | [[Category: Biou V]] |
| - | [[Category: Cherfils, J]] | + | [[Category: Campanacci V]] |
| - | [[Category: Duarte, L]] | + | [[Category: Cherfils J]] |
| - | [[Category: Navaza, J]] | + | [[Category: Duarte L]] |
| - | [[Category: Zeghouf, M]] | + | [[Category: Navaza J]] |
| - | [[Category: Endocytosis]]
| + | [[Category: Zeghouf M]] |
| - | [[Category: Protein transport]]
| + | |
| Structural highlights
Function
IQEC1_HUMAN In addition to accelerate GTP gamma S binding by ARFs of all three classes, it appears to function preferentially as a guanine nucleotide exchange protein for ARF6, mediating internalisation of beta-1 integrin.[1] [2]
Publication Abstract from PubMed
The mechanisms whereby guanine nucleotide exchange factors (GEFs) coordinate their subcellular targeting to their activation of small GTPases remain poorly understood. Here we analyzed how membranes control the efficiency of human BRAG2, an ArfGEF involved in receptor endocytosis, Wnt signaling, and tumor invasion. The crystal structure of an Arf1-BRAG2 complex that mimics a membrane-bound intermediate revealed an atypical PH domain that is constitutively anchored to the catalytic Sec7 domain and interacts with Arf. Combined with the quantitative analysis of BRAG2 exchange activity reconstituted on membranes, we find that this PH domain potentiates nucleotide exchange by about 2,000-fold by cumulative conformational and membrane-targeting contributions. Furthermore, it restricts BRAG2 activity to negatively charged membranes without phosphoinositide specificity, using a positively charged surface peripheral to but excluding the canonical lipid-binding pocket. This suggests a model of BRAG2 regulation along the early endosomal pathway that expands the repertoire of GEF regulatory mechanisms. Notably, it departs from the auto-inhibitory and feedback loop paradigm emerging from studies of SOS and cytohesins. It also uncovers a novel mechanism of unspecific lipid-sensing by PH domains that may allow sustained binding to maturating membranes.
Integrated Conformational and Lipid-Sensing Regulation of Endosomal ArfGEF BRAG2.,Aizel K, Biou V, Navaza J, Duarte LV, Campanacci V, Cherfils J, Zeghouf M PLoS Biol. 2013 Sep;11(9):e1001652. doi: 10.1371/journal.pbio.1001652. Epub 2013 , Sep 10. PMID:24058294[3]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Someya A, Sata M, Takeda K, Pacheco-Rodriguez G, Ferrans VJ, Moss J, Vaughan M. ARF-GEP(100), a guanine nucleotide-exchange protein for ADP-ribosylation factor 6. Proc Natl Acad Sci U S A. 2001 Feb 27;98(5):2413-8. PMID:11226253 doi:http://dx.doi.org/10.1073/pnas.051634798
- ↑ Dunphy JL, Moravec R, Ly K, Lasell TK, Melancon P, Casanova JE. The Arf6 GEF GEP100/BRAG2 regulates cell adhesion by controlling endocytosis of beta1 integrins. Curr Biol. 2006 Feb 7;16(3):315-20. PMID:16461286 doi:http://dx.doi.org/10.1016/j.cub.2005.12.032
- ↑ Aizel K, Biou V, Navaza J, Duarte LV, Campanacci V, Cherfils J, Zeghouf M. Integrated Conformational and Lipid-Sensing Regulation of Endosomal ArfGEF BRAG2. PLoS Biol. 2013 Sep;11(9):e1001652. doi: 10.1371/journal.pbio.1001652. Epub 2013 , Sep 10. PMID:24058294 doi:10.1371/journal.pbio.1001652
|
