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5ulx
From Proteopedia
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| - | '''Unreleased structure''' | ||
| - | + | ==Structure of human DNA polymerase iota bound to template 1-methyl-deoxyadenosine crystallized in the presence of dCTP== | |
| + | <StructureSection load='5ulx' size='340' side='right'caption='[[5ulx]], [[Resolution|resolution]] 1.96Å' scene=''> | ||
| + | == Structural highlights == | ||
| + | <table><tr><td colspan='2'>[[5ulx]] is a 3 chain structure with sequence from [https://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens] and [https://en.wikipedia.org/wiki/Unidentified Unidentified]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=5ULX OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=5ULX 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]] 1.96Å</td></tr> | ||
| + | <tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=CL:CHLORIDE+ION'>CL</scene>, <scene name='pdbligand=DOC:2,3-DIDEOXYCYTIDINE-5-MONOPHOSPHATE'>DOC</scene>, <scene name='pdbligand=MA7:1N-METHYLADENOSINE-5-MONOPHOSPHATE'>MA7</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=5ulx FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=5ulx OCA], [https://pdbe.org/5ulx PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=5ulx RCSB], [https://www.ebi.ac.uk/pdbsum/5ulx PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=5ulx ProSAT]</span></td></tr> | ||
| + | </table> | ||
| + | == Function == | ||
| + | [https://www.uniprot.org/uniprot/POLI_HUMAN POLI_HUMAN] Error-prone DNA polymerase specifically involved in DNA repair. Plays an important role in translesion synthesis, where the normal high-fidelity DNA polymerases cannot proceed and DNA synthesis stalls. Favors Hoogsteen base-pairing in the active site. Inserts the correct base with high-fidelity opposite an adenosine template. Exhibits low fidelity and efficiency opposite a thymidine template, where it will preferentially insert guanosine. May play a role in hypermutation of immunogobulin genes. Forms a Schiff base with 5'-deoxyribose phosphate at abasic sites, but may not have lyase activity.<ref>PMID:11013228</ref> <ref>PMID:11251121</ref> <ref>PMID:11387224</ref> <ref>PMID:12410315</ref> <ref>PMID:14630940</ref> <ref>PMID:15199127</ref> <ref>PMID:15254543</ref> | ||
| + | <div style="background-color:#fffaf0;"> | ||
| + | == Publication Abstract from PubMed == | ||
| + | N1-methyl-deoxyadenosine (1-MeA) is formed by methylation of deoxyadenosine at the N1 atom. 1-MeA presents a block to replicative DNA polymerases due to its inability to participate in Watson-Crick (W-C) base pairing. Here we determine how human DNA polymerase-iota (Poliota) promotes error-free replication across 1-MeA. Steady state kinetic analyses indicate that Poliota is ~100 fold more efficient in incorporating the correct nucleotide T versus the incorrect nucleotide C opposite 1-MeA. To understand the basis of this selectivity, we determined ternary structures of Poliota bound to template 1-MeA and incoming dTTP or dCTP. In both structures, template 1-MeA rotates to the syn conformation but pairs differently with dTTP versus dCTP. Thus, whereas dTTP partakes in stable Hoogsteen base pairing with 1-MeA, dCTP fails to gain a "foothold" and is largely disordered. Together, our kinetic and structural studies show how Poliota maintains discrimination between correct and incorrect incoming nucleotide opposite 1-MeA in preserving genome integrity. | ||
| - | + | Mechanism of error-free DNA synthesis across N1-methyl-deoxyadenosine by human DNA polymerase-iota.,Jain R, Choudhury JR, Buku A, Johnson RE, Prakash L, Prakash S, Aggarwal AK Sci Rep. 2017 Mar 8;7:43904. doi: 10.1038/srep43904. PMID:28272441<ref>PMID:28272441</ref> | |
| - | + | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |
| - | [[Category: | + | </div> |
| - | [[Category: | + | <div class="pdbe-citations 5ulx" style="background-color:#fffaf0;"></div> |
| - | [[Category: Aggarwal | + | |
| + | ==See Also== | ||
| + | *[[DNA polymerase 3D structures|DNA polymerase 3D structures]] | ||
| + | == References == | ||
| + | <references/> | ||
| + | __TOC__ | ||
| + | </StructureSection> | ||
| + | [[Category: Homo sapiens]] | ||
| + | [[Category: Large Structures]] | ||
| + | [[Category: Unidentified]] | ||
| + | [[Category: Aggarwal AK]] | ||
| + | [[Category: Jain R]] | ||
Current revision
Structure of human DNA polymerase iota bound to template 1-methyl-deoxyadenosine crystallized in the presence of dCTP
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