This old version of Proteopedia is provided for student assignments while the new version is undergoing repairs. Content and edits done in this old version of Proteopedia after March 1, 2026 will eventually be lost when it is retired in about June of 2026.

Apply for new accounts at the new Proteopedia. Your logins will work in both the old and new versions.

1i4d

From Proteopedia

(Difference between revisions)

Jump to: navigation, search

Revision as of 15:58, 12 October 2017

CRYSTAL STRUCTURE ANALYSIS OF RAC1-GDP COMPLEXED WITH ARFAPTIN (P21)

Structural highlights

1i4d is a 3 chain structure with sequence from Human. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Ligands:	,
Related:	1i49, 1i4l
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

[ARFP2_HUMAN] Putative target protein of ADP-ribosylation factor. Involved in membrane ruffling. [RAC1_HUMAN] Plasma membrane-associated small GTPase which cycles between active GTP-bound and inactive GDP-bound states. In its active state, binds to a variety of effector proteins to regulate cellular responses such as secretory processes, phagocytosis of apoptotic cells, epithelial cell polarization and growth-factor induced formation of membrane ruffles. Rac1 p21/rho GDI heterodimer is the active component of the cytosolic factor sigma 1, which is involved in stimulation of the NADPH oxidase activity in macrophages (By similarity). Essential for the SPATA13-mediated regulation of cell migration and adhesion assembly and disassembly. Stimulates PKN2 kinase activity. In concert with RAB7A, plays a role in regulating the formation of RBs (ruffled borders) in osteoclasts. In glioma cells, promotes cell migration and invasion.^[1] ^[2] ^[3] ^[4] ^[5] Isoform B has an accelerated GEF-independent GDP/GTP exchange and an impaired GTP hydrolysis, which is restored partially by GTPase-activating proteins. It is able to bind to the GTPase-binding domain of PAK but not full-length PAK in a GTP-dependent manner, suggesting that the insertion does not completely abolish effector interaction.^[6] ^[7] ^[8] ^[9] ^[10]

Evolutionary Conservation

Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.

Publication Abstract from PubMed

Small G proteins are GTP-dependent molecular switches that regulate numerous cellular functions. They can be classified into homologous subfamilies that are broadly associated with specific biological processes. Cross-talk between small G-protein families has an important role in signalling, but the mechanism by which it occurs is poorly understood. The coordinated action of Arf and Rho family GTPases is required to regulate many cellular processes including lipid signalling, cell motility and Golgi function. Arfaptin is a ubiquitously expressed protein implicated in mediating cross-talk between Rac (a member of the Rho family) and Arf small GTPases. Here we show that Arfaptin binds specifically to GTP-bound Arf1 and Arf6, but binds to Rac.GTP and Rac.GDP with similar affinities. The X-ray structure of Arfaptin reveals an elongated, crescent-shaped dimer of three-helix coiled-coils. Structures of Arfaptin with Rac bound to either GDP or the slowly hydrolysable analogue GMPPNP show that the switch regions adopt similar conformations in both complexes. Our data highlight fundamental differences between the molecular mechanisms of Rho and Ras family signalling, and suggest a model of Arfaptin-mediated synergy between the Arf and Rho family signalling pathways.

The structural basis of Arfaptin-mediated cross-talk between Rac and Arf signalling pathways.,Tarricone C, Xiao B, Justin N, Walker PA, Rittinger K, Gamblin SJ, Smerdon SJ Nature. 2001 May 10;411(6834):215-9. PMID:11346801^[11]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

References

↑ Ridley AJ, Paterson HF, Johnston CL, Diekmann D, Hall A. The small GTP-binding protein rac regulates growth factor-induced membrane ruffling. Cell. 1992 Aug 7;70(3):401-10. PMID:1643658
↑ Vincent S, Settleman J. The PRK2 kinase is a potential effector target of both Rho and Rac GTPases and regulates actin cytoskeletal organization. Mol Cell Biol. 1997 Apr;17(4):2247-56. PMID:9121475
↑ Bristow JM, Sellers MH, Majumdar D, Anderson B, Hu L, Webb DJ. The Rho-family GEF Asef2 activates Rac to modulate adhesion and actin dynamics and thereby regulate cell migration. J Cell Sci. 2009 Dec 15;122(Pt 24):4535-46. doi: 10.1242/jcs.053728. Epub 2009, Nov 24. PMID:19934221 doi:10.1242/jcs.053728
↑ Hamill KJ, Hopkinson SB, DeBiase P, Jones JC. BPAG1e maintains keratinocyte polarity through beta4 integrin-mediated modulation of Rac1 and cofilin activities. Mol Biol Cell. 2009 Jun;20(12):2954-62. doi: 10.1091/mbc.E09-01-0051. Epub 2009, Apr 29. PMID:19403692 doi:10.1091/mbc.E09-01-0051
↑ Li X, Lee AY. Semaphorin 5A and plexin-B3 inhibit human glioma cell motility through RhoGDIalpha-mediated inactivation of Rac1 GTPase. J Biol Chem. 2010 Oct 15;285(42):32436-45. doi: 10.1074/jbc.M110.120451. Epub, 2010 Aug 9. PMID:20696765 doi:10.1074/jbc.M110.120451
↑ Ridley AJ, Paterson HF, Johnston CL, Diekmann D, Hall A. The small GTP-binding protein rac regulates growth factor-induced membrane ruffling. Cell. 1992 Aug 7;70(3):401-10. PMID:1643658
↑ Vincent S, Settleman J. The PRK2 kinase is a potential effector target of both Rho and Rac GTPases and regulates actin cytoskeletal organization. Mol Cell Biol. 1997 Apr;17(4):2247-56. PMID:9121475
↑ Bristow JM, Sellers MH, Majumdar D, Anderson B, Hu L, Webb DJ. The Rho-family GEF Asef2 activates Rac to modulate adhesion and actin dynamics and thereby regulate cell migration. J Cell Sci. 2009 Dec 15;122(Pt 24):4535-46. doi: 10.1242/jcs.053728. Epub 2009, Nov 24. PMID:19934221 doi:10.1242/jcs.053728
↑ Hamill KJ, Hopkinson SB, DeBiase P, Jones JC. BPAG1e maintains keratinocyte polarity through beta4 integrin-mediated modulation of Rac1 and cofilin activities. Mol Biol Cell. 2009 Jun;20(12):2954-62. doi: 10.1091/mbc.E09-01-0051. Epub 2009, Apr 29. PMID:19403692 doi:10.1091/mbc.E09-01-0051
↑ Li X, Lee AY. Semaphorin 5A and plexin-B3 inhibit human glioma cell motility through RhoGDIalpha-mediated inactivation of Rac1 GTPase. J Biol Chem. 2010 Oct 15;285(42):32436-45. doi: 10.1074/jbc.M110.120451. Epub, 2010 Aug 9. PMID:20696765 doi:10.1074/jbc.M110.120451
↑ Tarricone C, Xiao B, Justin N, Walker PA, Rittinger K, Gamblin SJ, Smerdon SJ. The structural basis of Arfaptin-mediated cross-talk between Rac and Arf signalling pathways. Nature. 2001 May 10;411(6834):215-9. PMID:11346801 doi:http://dx.doi.org/10.1038/35075620

1 Structural highlights
2 Function
3 Evolutionary Conservation
4 Publication Abstract from PubMed
5 See Also
6 References

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/1i4d"

@@ Line 1: / Line 1: @@
 ==CRYSTAL STRUCTURE ANALYSIS OF RAC1-GDP COMPLEXED WITH ARFAPTIN (P21)==
 <StructureSection load='1i4d' size='340' side='right' caption='[[1i4d]], [[Resolution|resolution]] 2.50&Aring;' scene=''>
@@ Line 5: / Line 6: @@
 </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='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[1i49|1i49]], [[1i4l|1i4l]]</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=1i4d FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1i4d OCA], [http://pdbe.org/1i4d PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=1i4d RCSB], [http://www.ebi.ac.uk/pdbsum/1i4d PDBsum]</span></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=1i4d FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1i4d OCA], [http://pdbe.org/1i4d PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=1i4d RCSB], [http://www.ebi.ac.uk/pdbsum/1i4d PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=1i4d ProSAT]</span></td></tr>
 </table>
 == Function ==
@@ Line 28: / Line 29: @@
 </div>
 <div class="pdbe-citations 1i4d" style="background-color:#fffaf0;"></div>
+==See Also==
+*[[Rac|Rac]]
 == References ==
 <references/>
@@ Line 38: / Line 42: @@
 [[Category: Tarricone, C]]
 [[Category: Xiao, B]]
+[[Category: Coiled coil]]
 [[Category: Complex]]
 [[Category: G-protein]]
 [[Category: Signaling protein]]

1i4d

From Proteopedia

Revision as of 15:58, 12 October 2017

CRYSTAL STRUCTURE ANALYSIS OF RAC1-GDP COMPLEXED WITH ARFAPTIN (P21)

Structural highlights

Function

Evolutionary Conservation

Publication Abstract from PubMed

See Also

References

Contents

Proteopedia Page Contributors and Editors (what is this?)

Views

Personal tools

Navigation

Search

Toolbox