View source for 3khr


==Dpo4 post-extension ternary complex with the correct C opposite the 2-aminofluorene-guanine [AF]G lesion==
<StructureSection load='3khr' size='340' side='right'caption='[[3khr]], [[Resolution|resolution]] 2.01&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[3khr]] is a 6 chain structure with sequence from [https://en.wikipedia.org/wiki/Saccharolobus_solfataricus_P2 Saccharolobus solfataricus P2]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3KHR OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=3KHR 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]] 2.01&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=AF:2-AMINOFLUORENE'>AF</scene>, <scene name='pdbligand=CA:CALCIUM+ION'>CA</scene>, <scene name='pdbligand=DDG:2,3-DIDEOXY-GUANOSINE-5-MONOPHOSPHATE'>DDG</scene>, <scene name='pdbligand=TTP:THYMIDINE-5-TRIPHOSPHATE'>TTP</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=3khr FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3khr OCA], [https://pdbe.org/3khr PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=3khr RCSB], [https://www.ebi.ac.uk/pdbsum/3khr PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=3khr ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/DPO4_SACS2 DPO4_SACS2] Poorly processive, error-prone DNA polymerase involved in untargeted mutagenesis. Copies undamaged DNA at stalled replication forks, which arise in vivo from mismatched or misaligned primer ends. These misaligned primers can be extended by PolIV. Exhibits no 3'-5' exonuclease (proofreading) activity. It is involved in translesional synthesis.
== Evolutionary Conservation ==
[[Image:Consurf_key_small.gif|200px|right]]
Check<jmol>
  <jmolCheckbox>
    <scriptWhenChecked>; select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/kh/3khr_consurf.spt"</scriptWhenChecked>
    <scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked>
    <text>to colour the structure by Evolutionary Conservation</text>
  </jmolCheckbox>
</jmol>, as determined by [http://consurfdb.tau.ac.il/ ConSurfDB]. You may read the [[Conservation%2C_Evolutionary|explanation]] of the method and the full data available from [http://bental.tau.ac.il/new_ConSurfDB/main_output.php?pdb_ID=3khr ConSurf].
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== Publication Abstract from PubMed ==
The aromatic amine carcinogen 2-aminofluorene (AF) forms covalent adducts with DNA, predominantly with guanine at the C8 position. Such lesions are bypassed by Y-family polymerases such as Dpo4 via error-free and error-prone mechanisms. We show that Dpo4 catalyzes elongation from a correct 3'-terminal cytosine opposite [AF]G in a nonrepetitive template sequence with low efficiency. This extension leads to cognate full-length product, as well as mis-elongated products containing base mutations and deletions. Crystal structures of the Dpo4 ternary complex, with the 3'-terminal primer cytosine base opposite [AF]G in the anti conformation and with the AF moiety positioned in the major groove, reveal both accurate and misalignment-mediated mutagenic extension pathways. The mutagenic template-primer-dNTP arrangement is promoted by interactions between the polymerase and the bulky lesion rather than by a base pair-stabilized misaligment. Further extension leads to semitargeted mutations via this proposed polymerase-guided mechanism.

Mechanism of error-free and semitargeted mutagenic bypass of an aromatic amine lesion by Y-family polymerase Dpo4.,Rechkoblit O, Kolbanovskiy A, Malinina L, Geacintov NE, Broyde S, Patel DJ Nat Struct Mol Biol. 2010 Mar;17(3):379-88. Epub 2010 Feb 14. PMID:20154704<ref>PMID:20154704</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
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<div class="pdbe-citations 3khr" style="background-color:#fffaf0;"></div>

==See Also==
*[[DNA polymerase 3D structures|DNA polymerase 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Saccharolobus solfataricus P2]]
[[Category: Malinina L]]
[[Category: Patel DJ]]
[[Category: Rechkoblit O]]