View source for 6djm


==Cryo-EM structure of AMPPNP-actin filaments==
<StructureSection load='6djm' size='340' side='right'caption='[[6djm]], [[Resolution|resolution]] 3.10&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[6djm]] is a 4 chain structure with sequence from [http://en.wikipedia.org/wiki/Gallus_gallus Gallus gallus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=6DJM OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=6DJM FirstGlance]. <br>
</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=ANP:PHOSPHOAMINOPHOSPHONIC+ACID-ADENYLATE+ESTER'>ANP</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene></td></tr>
<tr id='NonStdRes'><td class="sblockLbl"><b>[[Non-Standard_Residue|NonStd Res:]]</b></td><td class="sblockDat"><scene name='pdbligand=HIC:4-METHYL-HISTIDINE'>HIC</scene></td></tr>
<tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[6djo|6djo]], [[6djn|6djn]]</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=6djm FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=6djm OCA], [http://pdbe.org/6djm PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=6djm RCSB], [http://www.ebi.ac.uk/pdbsum/6djm PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=6djm ProSAT]</span></td></tr>
</table>
== Function ==
[[http://www.uniprot.org/uniprot/ACTS_CHICK ACTS_CHICK]] Actins are highly conserved proteins that are involved in various types of cell motility and are ubiquitously expressed in all eukaryotic cells. 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
We used cryo-electron microscopy (cryo-EM) to reconstruct actin filaments with bound AMPPNP (beta,gamma-imidoadenosine 5'-triphosphate, an ATP analog, resolution 3.1 A), ADP-Pi (ADP with inorganic phosphate, resolution 3.1 A), or ADP (resolution 3.6 A). Subunits in the three filaments have similar backbone conformations, so assembly rather than ATP hydrolysis or phosphate dissociation is responsible for their flattened conformation in filaments. Polymerization increases the rate of ATP hydrolysis by changing the positions of the side chains of Q137 and H161 in the active site. Flattening during assembly also promotes interactions along both the long-pitch and short-pitch helices. In particular, conformational changes in subdomain 3 open up multiple favorable interactions with the DNase-I binding loop in subdomain 2 of the adjacent subunit. Subunits at the barbed end of the filament are likely to be in this favorable conformation, while monomers are not. This difference explains why filaments grow faster at the barbed end than the pointed end. When phosphate dissociates from ADP-Pi-actin through a backdoor channel, the conformation of the C terminus changes so it distorts the DNase binding loop, which allows cofilin binding, and a network of interactions among S14, H73, G74, N111, R177, and G158 rearranges to open the phosphate release site.

Mechanism of actin polymerization revealed by cryo-EM structures of actin filaments with three different bound nucleotides.,Chou SZ, Pollard TD Proc Natl Acad Sci U S A. 2019 Feb 13. pii: 1807028115. doi:, 10.1073/pnas.1807028115. PMID:30760599<ref>PMID:30760599</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 6djm" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Gallus gallus]]
[[Category: Large Structures]]
[[Category: Chou, S Z]]
[[Category: Pollard, T D]]
[[Category: Actin]]
[[Category: Amppnp]]
[[Category: Atpase]]
[[Category: Contractile protein]]
[[Category: Filament]]