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.

4n3y

From Proteopedia

(Difference between revisions)

Jump to: navigation, search

Current revision

Crystal structure of Rabex-5CC and Rabaptin-5C21 complex

Structural highlights

4n3y is a 3 chain structure with sequence from Homo sapiens. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Method:	X-ray diffraction, Resolution 2.2Å
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

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]

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^[4]

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
↑ 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/4n3y"

Categories: Homo sapiens | Large Structures | Ding J | Zhang T | Zhang Z

@@ Line 1: / Line 1: @@
-'''Unreleased structure'''
-The entry 4n3y is ON HOLD
+==Crystal structure of Rabex-5CC and Rabaptin-5C21 complex==
+<StructureSection load='4n3y' size='340' side='right'caption='[[4n3y]], [[Resolution|resolution]] 2.20&Aring;' scene=''>
+== Structural highlights ==
+<table><tr><td colspan='2'>[[4n3y]] is a 3 chain structure with sequence from [https://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4N3Y OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4N3Y FirstGlance]. <br>
+</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 2.2&#8491;</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=4n3y FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4n3y OCA], [https://pdbe.org/4n3y PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4n3y RCSB], [https://www.ebi.ac.uk/pdbsum/4n3y PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4n3y ProSAT]</span></td></tr>
+</table>
+== Function ==
+[https://www.uniprot.org/uniprot/RABX5_HUMAN 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).<ref>PMID:9323142</ref> <ref>PMID:11452015</ref> <ref>PMID:15339665</ref>
+<div style="background-color:#fffaf0;">
+== 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.
-Authors: Zhang, Z, Zhang, T, Ding, J
+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<ref>PMID:24957337</ref>
-Description: Crystal structure of Rabex-5CC and Rabaptin-5C21 complex
+From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
+</div>
+<div class="pdbe-citations 4n3y" style="background-color:#fffaf0;"></div>
+==See Also==
+*[[Rab5 GDP/GTP exchange factor|Rab5 GDP/GTP exchange factor]]
+== References ==
+<references/>
+__TOC__
+</StructureSection>
+[[Category: Homo sapiens]]
+[[Category: Large Structures]]
+[[Category: Ding J]]
+[[Category: Zhang T]]
+[[Category: Zhang Z]]

4n3y

From Proteopedia

Current revision

Crystal structure of Rabex-5CC 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