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.

4q9u

From Proteopedia

(Difference between revisions)

Jump to: navigation, search

Revision as of 07:20, 9 December 2015

Crystal structure of the Rab5, Rabex-5delta and Rabaptin-5C21 complex

Structural highlights

4q9u is a 8 chain structure. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Related:	4n3x, 4n3y, 4n3z
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum

Function

[RABX5_HUMAN] Rab effector protein acting as linker between gamma-adaptin, RAB4A or RAB5A. Involved in endocytic membrane fusion and membrane trafficking of recycling endosomes. Stimulates nucleotide exchange on RAB5A. Can act as a ubiquitin ligase (By similarity).^[1] ^[2] ^[3] [RABE1_HUMAN] Rab effector protein acting as linker between gamma-adaptin, RAB4A and RAB5A. Involved in endocytic membrane fusion and membrane trafficking of recycling endosomes. Stimulates RABGEF1 mediated nucleotide exchange on RAB5A.^[4] ^[5] ^[6] ^[7] [RAB5A_HUMAN] Required for the fusion of plasma membranes and early endosomes. Contributes to the regulation of filopodia extension.^[8]

Publication Abstract from PubMed

Rabex-5 and Rabaptin-5 function together to activate Rab5 and further promote early endosomal fusion in endocytosis. The Rabex-5 GEF activity is autoinhibited by the Rabex-5 CC domain (Rabex-5CC) and activated by the Rabaptin-5 C2-1 domain (Rabaptin-5C21) with yet unknown mechanism. We report here the crystal structures of Rabex-5 in complex with the dimeric Rabaptin-5C21 (Rabaptin-5C212) and in complex with Rabaptin-5C212 and Rab5, along with biophysical and biochemical analyses. We show that Rabex-5CC assumes an amphipathic alpha-helix which binds weakly to the substrate-binding site of the GEF domain, leading to weak autoinhibition of the GEF activity. Binding of Rabaptin-5C21 to Rabex-5 displaces Rabex-5CC to yield a largely exposed substrate-binding site, leading to release of the GEF activity. In the ternary complex the substrate-binding site of Rabex-5 is completely exposed to bind and activate Rab5. Our results reveal the molecular mechanism for the regulation of the Rabex-5 GEF activity.

Molecular mechanism for Rabex-5 GEF activation by Rabaptin-5.,Zhang Z, Zhang T, Wang S, Gong Z, Tang C, Chen J, Ding J Elife (Cambridge). 2014 Jun 23:e02687. doi: 10.7554/eLife.02687. PMID:24957337^[9]

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

References

↑ Horiuchi H, Lippe R, McBride HM, Rubino M, Woodman P, Stenmark H, Rybin V, Wilm M, Ashman K, Mann M, Zerial M. A novel Rab5 GDP/GTP exchange factor complexed to Rabaptin-5 links nucleotide exchange to effector recruitment and function. Cell. 1997 Sep 19;90(6):1149-59. PMID:9323142
↑ Lippe R, Miaczynska M, Rybin V, Runge A, Zerial M. Functional synergy between Rab5 effector Rabaptin-5 and exchange factor Rabex-5 when physically associated in a complex. Mol Biol Cell. 2001 Jul;12(7):2219-28. PMID:11452015
↑ Delprato A, Merithew E, Lambright DG. Structure, exchange determinants, and family-wide rab specificity of the tandem helical bundle and Vps9 domains of Rabex-5. Cell. 2004 Sep 3;118(5):607-17. PMID:15339665 doi:10.1016/j.cell.2004.08.009
↑ Stenmark H, Vitale G, Ullrich O, Zerial M. Rabaptin-5 is a direct effector of the small GTPase Rab5 in endocytic membrane fusion. Cell. 1995 Nov 3;83(3):423-32. PMID:8521472
↑ Nagelkerken B, Van Anken E, Van Raak M, Gerez L, Mohrmann K, Van Uden N, Holthuizen J, Pelkmans L, Van Der Sluijs P. Rabaptin4, a novel effector of the small GTPase rab4a, is recruited to perinuclear recycling vesicles. Biochem J. 2000 Mar 15;346 Pt 3:593-601. PMID:10698684
↑ Lippe R, Miaczynska M, Rybin V, Runge A, Zerial M. Functional synergy between Rab5 effector Rabaptin-5 and exchange factor Rabex-5 when physically associated in a complex. Mol Biol Cell. 2001 Jul;12(7):2219-28. PMID:11452015
↑ Deneka M, Neeft M, Popa I, van Oort M, Sprong H, Oorschot V, Klumperman J, Schu P, van der Sluijs P. Rabaptin-5alpha/rabaptin-4 serves as a linker between rab4 and gamma(1)-adaptin in membrane recycling from endosomes. EMBO J. 2003 Jun 2;22(11):2645-57. PMID:12773381 doi:http://dx.doi.org/10.1093/emboj/cdg257
↑ Gauthier-Campbell C, Bredt DS, Murphy TH, El-Husseini Ael-D. Regulation of dendritic branching and filopodia formation in hippocampal neurons by specific acylated protein motifs. Mol Biol Cell. 2004 May;15(5):2205-17. Epub 2004 Feb 20. PMID:14978216 doi:10.1091/mbc.E03-07-0493
↑ Zhang Z, Zhang T, Wang S, Gong Z, Tang C, Chen J, Ding J. Molecular mechanism for Rabex-5 GEF activation by Rabaptin-5. Elife (Cambridge). 2014 Jun 23:e02687. doi: 10.7554/eLife.02687. PMID:24957337 doi:http://dx.doi.org/10.7554/eLife.02687

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

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/4q9u"

@@ Line 4: / Line 4: @@
 <table><tr><td colspan='2'>[[4q9u]] is a 8 chain structure. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4Q9U OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=4Q9U FirstGlance]. <br>
 </td></tr><tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[4n3x|4n3x]], [[4n3y|4n3y]], [[4n3z|4n3z]]</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=4q9u FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4q9u OCA], [http://www.rcsb.org/pdb/explore.do?structureId=4q9u RCSB], [http://www.ebi.ac.uk/pdbsum/4q9u 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=4q9u FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4q9u OCA], [http://pdbe.org/4q9u PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=4q9u RCSB], [http://www.ebi.ac.uk/pdbsum/4q9u PDBsum]</span></td></tr>
 </table>
 == Function ==
@@ Line 16: / Line 16: @@
 From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
 </div>
+<div class="pdbe-citations 4q9u" style="background-color:#fffaf0;"></div>
+==See Also==
+*[[Rab5 GDP/GTP exchange factor|Rab5 GDP/GTP exchange factor]]
 == References ==
 <references/>

4q9u

From Proteopedia

Revision as of 07:20, 9 December 2015

Crystal structure of the Rab5, Rabex-5delta and Rabaptin-5C21 complex

Structural highlights

Function

Publication Abstract from PubMed

See Also

References

Contents

Proteopedia Page Contributors and Editors (what is this?)

Views

Personal tools

Navigation

Search

Toolbox