View source for 4iqj


==Structure of PolIIIalpha-Tauc-DNA complex suggests an atomic model of the replisome==
<StructureSection load='4iqj' size='340' side='right'caption='[[4iqj]], [[Resolution|resolution]] 3.20&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[4iqj]] is a 16 chain structure with sequence from [https://en.wikipedia.org/wiki/Thermus_aquaticus Thermus aquaticus] and [https://en.wikipedia.org/wiki/Synthetic_construct Synthetic construct]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4IQJ OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4IQJ 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]] 3.2&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=DOC:2,3-DIDEOXYCYTIDINE-5-MONOPHOSPHATE'>DOC</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene>, <scene name='pdbligand=ZN:ZINC+ION'>ZN</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=4iqj FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4iqj OCA], [https://pdbe.org/4iqj PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4iqj RCSB], [https://www.ebi.ac.uk/pdbsum/4iqj PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4iqj ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/DPO3A_THEAQ DPO3A_THEAQ] DNA polymerase III is a complex, multichain enzyme responsible for most of the replicative synthesis in bacteria. This DNA polymerase also exhibits 3' to 5' exonuclease activity. The alpha chain is the DNA polymerase (By similarity).
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
The C-terminal domain (CTD) of the tau subunit of the clamp loader (tauc) binds to both the DnaB helicase and the DNA polymerase III alpha subunit (PolIIIalpha), and determines their relative positions and orientations on the leading and lagging strands. Here, we present a 3.2 A resolution structure of Thermus aquaticus PolIIIalpha in complex with tauc and a DNA substrate. The structure reveals that the CTD of tauc interacts with the CTD of PolIIIalpha through its C-terminal helix and the adjacent loop. Additionally, in this complex PolIIIalpha displays an open conformation that includes the reorientations of the oligonucleotide-binding fold and the thumb domain, which may be an indirect result of crystal packing due to the presence of the tauc. Nevertheless, the position of the tauc on PolIIIalpha allows us to suggest an approximate model for how the PolIIIalpha is oriented and positioned on the DnaB helicase.

Structure of the PolIIIalpha-tauc-DNA complex suggests an atomic model of the replisome.,Liu B, Lin J, Steitz TA Structure. 2013 Apr 2;21(4):658-64. doi: 10.1016/j.str.2013.02.002. Epub 2013 Mar, 7. PMID:23478062<ref>PMID:23478062</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 4iqj" style="background-color:#fffaf0;"></div>

==See Also==
*[[DNA polymerase 3D structures|DNA polymerase 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Synthetic construct]]
[[Category: Thermus aquaticus]]
[[Category: Lin J]]
[[Category: Liu B]]
[[Category: Steitz T]]