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| | ==Human DNA polymerase iota incorporating dGTP opposite 8-oxo-guanine== | | ==Human DNA polymerase iota incorporating dGTP opposite 8-oxo-guanine== |
| | <StructureSection load='3q8r' size='340' side='right' caption='[[3q8r]], [[Resolution|resolution]] 2.45Å' scene=''> | | <StructureSection load='3q8r' size='340' side='right' caption='[[3q8r]], [[Resolution|resolution]] 2.45Å' scene=''> |
| | == Structural highlights == | | == Structural highlights == |
| - | <table><tr><td colspan='2'>[[3q8r]] is a 3 chain structure with sequence from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3Q8R OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=3Q8R FirstGlance]. <br> | + | <table><tr><td colspan='2'>[[3q8r]] is a 3 chain structure with sequence from [http://en.wikipedia.org/wiki/Human Human]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3Q8R OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=3Q8R FirstGlance]. <br> |
| | </td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=DGT:2-DEOXYGUANOSINE-5-TRIPHOSPHATE'>DGT</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene></td></tr> | | </td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=DGT:2-DEOXYGUANOSINE-5-TRIPHOSPHATE'>DGT</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=8OG:8-OXO-2-DEOXY-GUANOSINE-5-MONOPHOSPHATE'>8OG</scene></td></tr> | | <tr id='NonStdRes'><td class="sblockLbl"><b>[[Non-Standard_Residue|NonStd Res:]]</b></td><td class="sblockDat"><scene name='pdbligand=8OG:8-OXO-2-DEOXY-GUANOSINE-5-MONOPHOSPHATE'>8OG</scene></td></tr> |
| | <tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[3q8p|3q8p]], [[3q8q|3q8q]], [[3q8s|3q8s]]</td></tr> | | <tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[3q8p|3q8p]], [[3q8q|3q8q]], [[3q8s|3q8s]]</td></tr> |
| - | <tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">POLI, RAD30B ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=9606 Homo sapiens])</td></tr> | + | <tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">POLI, RAD30B ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=9606 HUMAN])</td></tr> |
| | <tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/DNA-directed_DNA_polymerase DNA-directed DNA polymerase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.7.7.7 2.7.7.7] </span></td></tr> | | <tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/DNA-directed_DNA_polymerase DNA-directed DNA polymerase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.7.7.7 2.7.7.7] </span></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=3q8r FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3q8r OCA], [http://www.rcsb.org/pdb/explore.do?structureId=3q8r RCSB], [http://www.ebi.ac.uk/pdbsum/3q8r PDBsum]</span></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=3q8r FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3q8r OCA], [http://pdbe.org/3q8r PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=3q8r RCSB], [http://www.ebi.ac.uk/pdbsum/3q8r PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=3q8r ProSAT]</span></td></tr> |
| | </table> | | </table> |
| | == Function == | | == Function == |
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| | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> |
| | </div> | | </div> |
| | + | <div class="pdbe-citations 3q8r" style="background-color:#fffaf0;"></div> |
| | | | |
| | ==See Also== | | ==See Also== |
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| | </StructureSection> | | </StructureSection> |
| | [[Category: DNA-directed DNA polymerase]] | | [[Category: DNA-directed DNA polymerase]] |
| - | [[Category: Homo sapiens]] | + | [[Category: Human]] |
| | [[Category: Kirouac, K N]] | | [[Category: Kirouac, K N]] |
| | [[Category: Ling, H]] | | [[Category: Ling, H]] |
| | [[Category: Dna polymerase]] | | [[Category: Dna polymerase]] |
| | [[Category: Transferase-dna complex]] | | [[Category: Transferase-dna complex]] |
| Structural highlights
3q8r is a 3 chain structure with sequence from Human. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
| | Ligands: | , |
| NonStd Res: | |
| Related: | 3q8p, 3q8q, 3q8s |
| Gene: | POLI, RAD30B (HUMAN) |
| Activity: | DNA-directed DNA polymerase, with EC number 2.7.7.7 |
| Resources: | FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT |
Function
[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.[1] [2] [3] [4] [5] [6] [7]
Publication Abstract from PubMed
The 8-oxo-guanine (8-oxo-G) lesion is the most abundant and mutagenic oxidative DNA damage existing in the genome. Due to its dual coding nature, 8-oxo-G causes most DNA polymerases to misincorporate adenine. Human Y-family DNA polymerase iota (poliota) preferentially incorporates the correct cytosine nucleotide opposite 8-oxo-G. This unique specificity may contribute to poliota's biological role in cellular protection against oxidative stress. However, the structural basis of this preferential cytosine incorporation is currently unknown. Here we present four crystal structures of poliota in complex with DNA containing an 8-oxo-G lesion, paired with correct dCTP or incorrect dATP, dGTP, and dTTP nucleotides. An exceptionally narrow poliota active site restricts the purine bases in a syn conformation, which prevents the dual coding properties of 8-oxo-G by inhibiting syn/anti conformational equilibrium. More importantly, the 8-oxo-G base in a syn conformation is not mutagenic in poliota because its Hoogsteen edge does not form a stable base pair with dATP in the narrow active site. Instead, the syn 8-oxo-G template base forms the most stable replicating base pair with correct dCTP due to its small pyrimidine base size and enhanced hydrogen bonding with the Hoogsteen edge of 8-oxo-G. In combination with site directed mutagenesis, we show that Gln59 in the finger domain specifically interacts with the additional O(8) atom of the lesion base, which influences nucleotide selection, enzymatic efficiency, and replication stalling at the lesion site. Our work provides the structural mechanism of high-fidelity 8-oxo-G replication by a human DNA polymerase.
Unique active site promotes error-free replication opposite an 8-oxo-guanine lesion by human DNA polymerase iota.,Kirouac KN, Ling H Proc Natl Acad Sci U S A. 2011 Feb 22;108(8):3210-5. Epub 2011 Feb 7. PMID:21300901[8]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ Tissier A, Frank EG, McDonald JP, Iwai S, Hanaoka F, Woodgate R. Misinsertion and bypass of thymine-thymine dimers by human DNA polymerase iota. EMBO J. 2000 Oct 2;19(19):5259-66. PMID:11013228 doi:http://dx.doi.org/10.1093/emboj/19.19.5259
- ↑ Bebenek K, Tissier A, Frank EG, McDonald JP, Prasad R, Wilson SH, Woodgate R, Kunkel TA. 5'-Deoxyribose phosphate lyase activity of human DNA polymerase iota in vitro. Science. 2001 Mar 16;291(5511):2156-9. PMID:11251121 doi:http://dx.doi.org/10.1126/science.1058386
- ↑ Frank EG, Tissier A, McDonald JP, Rapic-Otrin V, Zeng X, Gearhart PJ, Woodgate R. Altered nucleotide misinsertion fidelity associated with poliota-dependent replication at the end of a DNA template. EMBO J. 2001 Jun 1;20(11):2914-22. PMID:11387224 doi:http://dx.doi.org/10.1093/emboj/20.11.2914
- ↑ Faili A, Aoufouchi S, Flatter E, Gueranger Q, Reynaud CA, Weill JC. Induction of somatic hypermutation in immunoglobulin genes is dependent on DNA polymerase iota. Nature. 2002 Oct 31;419(6910):944-7. PMID:12410315 doi:http://dx.doi.org/10.1038/nature01117
- ↑ Haracska L, Prakash L, Prakash S. A mechanism for the exclusion of low-fidelity human Y-family DNA polymerases from base excision repair. Genes Dev. 2003 Nov 15;17(22):2777-85. PMID:14630940 doi:10.1101/gad.1146103
- ↑ Washington MT, Minko IG, Johnson RE, Wolfle WT, Harris TM, Lloyd RS, Prakash S, Prakash L. Efficient and error-free replication past a minor-groove DNA adduct by the sequential action of human DNA polymerases iota and kappa. Mol Cell Biol. 2004 Jul;24(13):5687-93. PMID:15199127 doi:http://dx.doi.org/10.1128/MCB.24.13.5687-5693.2004
- ↑ Nair DT, Johnson RE, Prakash S, Prakash L, Aggarwal AK. Replication by human DNA polymerase-iota occurs by Hoogsteen base-pairing. Nature. 2004 Jul 15;430(6997):377-80. PMID:15254543 doi:10.1038/nature02692
- ↑ Kirouac KN, Ling H. Unique active site promotes error-free replication opposite an 8-oxo-guanine lesion by human DNA polymerase iota. Proc Natl Acad Sci U S A. 2011 Feb 22;108(8):3210-5. Epub 2011 Feb 7. PMID:21300901 doi:10.1073/pnas.1013909108
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