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4m4r

From Proteopedia

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Epha4 ectodomain complex with ephrin a5

Structural highlights

4m4r is a 8 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 3.13Å
Ligands:
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

EPHA4_HUMAN Receptor tyrosine kinase which binds membrane-bound ephrin family ligands residing on adjacent cells, leading to contact-dependent bidirectional signaling into neighboring cells. The signaling pathway downstream of the receptor is referred to as forward signaling while the signaling pathway downstream of the ephrin ligand is referred to as reverse signaling. Highly promiscuous, it has the unique property among Eph receptors to bind and to be physiologically activated by both GPI-anchored ephrin-A and transmembrane ephrin-B ligands including EFNA1 and EFNB3. Upon activation by ephrin ligands, modulates cell morphology and integrin-dependent cell adhesion through regulation of the Rac, Rap and Rho GTPases activity. Plays an important role in the development of the nervous system controlling different steps of axonal guidance including the establishment of the corticospinal projections. May also control the segregation of motor and sensory axons during neuromuscular circuit development. Beside its role in axonal guidance plays a role in synaptic plasticity. Activated by EFNA1 phosphorylates CDK5 at 'Tyr-15' which in turn phosphorylates NGEF regulating RHOA and dendritic spine morphogenesis. In the nervous system, plays also a role in repair after injury preventing axonal regeneration and in angiogenesis playing a role in central nervous system vascular formation. Additionally, its promiscuity makes it available to participate in a variety of cell-cell signaling regulating for instance the development of the thymic epithelium.^[1]

Publication Abstract from PubMed

Eph receptor tyrosine kinases and their ephrin ligands mediate cell signaling during normal and oncogenic development. Eph signaling is initiated in a multistep process leading to the assembly of higher-order Eph/ephrin clusters that set off bidirectional signaling in interacting cells. Eph and ephrins are divided in two subclasses based on their abilities to bind and activate each other and on sequence conservation. EphA4 is an exception to the general rule because it can be activated by both A- and B-class ephrin ligands. Here we present high-resolution structures of the complete EphA4 ectodomain and its complexes with ephrin-A5. The structures reveal how ligand binding promotes conformational changes in the EphA4 ligand-binding domain allowing the formation of signaling clusters at the sites of cell-cell contact. In addition, the structural data, combined with structure-based mutagenesis, reveal a previously undescribed receptor-receptor interaction between the EphA4 ligand-binding and membrane-proximal fibronectin domains, which is functionally important for efficient receptor activation.

Insights into Eph receptor tyrosine kinase activation from crystal structures of the EphA4 ectodomain and its complex with ephrin-A5.,Xu K, Tzvetkova-Robev D, Xu Y, Goldgur Y, Chan YP, Himanen JP, Nikolov DB Proc Natl Acad Sci U S A. 2013 Sep 3;110(36):14634-9. doi:, 10.1073/pnas.1311000110. Epub 2013 Aug 19. PMID:23959867^[2]

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

References

↑ Fu WY, Chen Y, Sahin M, Zhao XS, Shi L, Bikoff JB, Lai KO, Yung WH, Fu AK, Greenberg ME, Ip NY. Cdk5 regulates EphA4-mediated dendritic spine retraction through an ephexin1-dependent mechanism. Nat Neurosci. 2007 Jan;10(1):67-76. Epub 2006 Dec 3. PMID:17143272 doi:10.1038/nn1811
↑ Xu K, Tzvetkova-Robev D, Xu Y, Goldgur Y, Chan YP, Himanen JP, Nikolov DB. Insights into Eph receptor tyrosine kinase activation from crystal structures of the EphA4 ectodomain and its complex with ephrin-A5. Proc Natl Acad Sci U S A. 2013 Sep 3;110(36):14634-9. doi:, 10.1073/pnas.1311000110. Epub 2013 Aug 19. PMID:23959867 doi:http://dx.doi.org/10.1073/pnas.1311000110

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/4m4r"

@@ Line 4: / Line 4: @@
 == Structural highlights ==
 <table><tr><td colspan='2'>[[4m4r]] is a 8 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=4M4R OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4M4R FirstGlance]. <br>
-</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=NAG:N-ACETYL-D-GLUCOSAMINE'>NAG</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]] 3.13&#8491;</td></tr>
+<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=NAG:N-ACETYL-D-GLUCOSAMINE'>NAG</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=4m4r FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4m4r OCA], [https://pdbe.org/4m4r PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4m4r RCSB], [https://www.ebi.ac.uk/pdbsum/4m4r PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4m4r ProSAT]</span></td></tr>
 </table>

4m4r

From Proteopedia

Current revision

Epha4 ectodomain complex with ephrin a5

Structural highlights

Function

Publication Abstract from PubMed

See Also

References

Contents

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