View source for 6yw7


==Cryo-EM structure of the ARP2/3 1A5C isoform complex.==
<StructureSection load='6yw7' size='340' side='right'caption='[[6yw7]], [[Resolution|resolution]] 4.50&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[6yw7]] is a 7 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=6YW7 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=6YW7 FirstGlance]. <br>
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">Electron Microscopy, [[Resolution|Resolution]] 4.5&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=ATP:ADENOSINE-5-TRIPHOSPHATE'>ATP</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=6yw7 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=6yw7 OCA], [https://pdbe.org/6yw7 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=6yw7 RCSB], [https://www.ebi.ac.uk/pdbsum/6yw7 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=6yw7 ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/ARP3_HUMAN ARP3_HUMAN] ATP-binding component of the Arp2/3 complex, a multiprotein complex that mediates actin polymerization upon stimulation by nucleation-promoting factor (NPF) (PubMed:9000076). The Arp2/3 complex mediates the formation of branched actin networks in the cytoplasm, providing the force for cell motility (PubMed:9000076). Seems to contact the pointed end of the daughter actin filament (PubMed:9000076). In podocytes, required for the formation of lamellipodia downstream of AVIL and PLCE1 regulation (PubMed:29058690). In addition to its role in the cytoplasmic cytoskeleton, the Arp2/3 complex also promotes actin polymerization in the nucleus, thereby regulating gene transcription and repair of damaged DNA (PubMed:17220302, PubMed:29925947). The Arp2/3 complex promotes homologous recombination (HR) repair in response to DNA damage by promoting nuclear actin polymerization, leading to drive motility of double-strand breaks (DSBs) (PubMed:29925947). Plays a role in ciliogenesis (PubMed:20393563).<ref>PMID:17220302</ref> <ref>PMID:20393563</ref> <ref>PMID:29058690</ref> <ref>PMID:29925947</ref> <ref>PMID:9000076</ref> 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
The Arp2/3 complex regulates many cellular processes by stimulating formation of branched actin filament networks. Because three of its seven subunits exist as two different isoforms, mammals produce a family of Arp2/3 complexes with different properties that may be suited to different physiological contexts. To shed light on how isoform diversification affects Arp2/3 function, we determined a 4.2 A resolution cryo-EM structure of the most active human Arp2/3 complex containing ARPC1B and ARPC5L, and compared it with the structure of the least active ARPC1A-ARPC5-containing complex. The architecture of each isoform-specific Arp2/3 complex is the same. Strikingly, however, the N-terminal half of ARPC5L is partially disordered compared to ARPC5, suggesting that this region of ARPC5/ARPC5L is an important determinant of complex activity. Confirming this idea, the nucleation activity of Arp2/3 complexes containing hybrid ARPC5/ARPC5L subunits is higher when the ARPC5L N-terminus is present, thereby providing insight into activity differences between the different Arp2/3 complexes.

Cryo-EM of human Arp2/3 complexes provides structural insights into actin nucleation modulation by ARPC5 isoforms.,von Loeffelholz O, Purkiss A, Cao L, Kjaer S, Kogata N, Romet-Lemonne G, Way M, Moores CA Biol Open. 2020 Jul 13. pii: bio.054304. doi: 10.1242/bio.054304. PMID:32661131<ref>PMID:32661131</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 6yw7" style="background-color:#fffaf0;"></div>

==See Also==
*[[Actin-related protein 3D structures|Actin-related protein 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Homo sapiens]]
[[Category: Large Structures]]
[[Category: Moores C]]
[[Category: Purkiss A]]
[[Category: Von Loeffelholz O]]