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4n3x

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Current revision

Crystal structure of Rabex-5 CC domain

Structural highlights

4n3x is a 4 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 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/4n3x"

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

@@ Line 4: / Line 4: @@
 == Structural highlights ==
 <table><tr><td colspan='2'>[[4n3x]] is a 4 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=4N3X OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4N3X FirstGlance]. <br>
-</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=4n3x FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4n3x OCA], [https://pdbe.org/4n3x PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4n3x RCSB], [https://www.ebi.ac.uk/pdbsum/4n3x PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4n3x ProSAT]</span></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]] 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=4n3x FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4n3x OCA], [https://pdbe.org/4n3x PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4n3x RCSB], [https://www.ebi.ac.uk/pdbsum/4n3x PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4n3x ProSAT]</span></td></tr>
 </table>
 == Function ==

4n3x

From Proteopedia

Current revision

Crystal structure of Rabex-5 CC domain

Structural highlights

Function

Publication Abstract from PubMed

See Also

References

Contents

Proteopedia Page Contributors and Editors (what is this?)

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