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5vrx

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Revision as of 10:30, 22 November 2017

Human DNA polymerase beta pre-catalytic 8-oxoG:dC extension complex with dTTP bound in Watson-Crick conformation

Structural highlights

5vrx is a 4 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:	5vry, 5vrz, 5vs0, 5vs1, 5vs2, 5vs3, 5vs4
Gene:	POLB (HUMAN)
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

[DPOLB_HUMAN] Repair polymerase that plays a key role in base-excision repair. Has 5'-deoxyribose-5-phosphate lyase (dRP lyase) activity that removes the 5' sugar phosphate and also acts as a DNA polymerase that adds one nucleotide to the 3' end of the arising single-nucleotide gap. Conducts 'gap-filling' DNA synthesis in a stepwise distributive fashion rather than in a processive fashion as for other DNA polymerases.^[1] ^[2] ^[3] ^[4]

Publication Abstract from PubMed

The oxidative DNA lesion 7,8-dihydro-2'-deoxyguanine (8-oxoG) often occurs in double-stranded DNA and poses a threat to genomic integrity due to the ability of 8-oxoG to form stable Watson-Crick base pairs with deoxycytidine (8-oxoG:dC) and Hoogsteen base pairs with deoxyadenosine (8-oxoG:dA). In humans, short-patch base excision repair of 8-oxoG:dA base pairs requires human DNA polymerase beta (hPolbeta) to bypass 8-oxoG. Previously, we have shown hPolbeta-catalyzed 8-oxoG bypass to exhibit low fidelity and identified a unique stacking interaction between the newly incorporated nucleotide (dCMP or dAMP) and the templating 8-oxoG. The effect of this stacking on the ability of hPolbeta to extend from 8-oxoG during long-patch base excision repair was unknown. Here we report pre-steady-state kinetics and time-dependent crystal structures to demonstrate that extension from both 8-oxoG:dC and 8-oxoG:dA base pairs is 18- to 580-fold less efficient compared to 8-oxoG bypass and that extension from 8-oxoG:dC over 8-oxoG:dA is favored by 15-fold. The overall decrease in efficiency of extension relative to 8-oxoG bypass is due to an alternative nucleotide binding conformation in the precatalytic ternary structures (hPolbeta.DNA.dNTP) for both extension contexts, wherein the incoming nucleotide is bound in either the canonical Watson-Crick base pair or a nonplanar base pair. In addition, the decreased stability of the ternary complex of 8-oxoG:dA extension results in further loss of efficiency when compared to 8-oxoG:dC extension. Therefore, we hypothesize that the inefficient extension from 8-oxoG:dA serves as a newly discovered fidelity checkpoint during base excision repair.

Time-Dependent Extension from an 8-Oxoguanine Lesion by Human DNA Polymerase Beta.,Reed AJ, Suo Z J Am Chem Soc. 2017 Jul 19;139(28):9684-9690. doi: 10.1021/jacs.7b05048. Epub, 2017 Jul 6. PMID:28682600^[5]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

References

↑ Bennett RA, Wilson DM 3rd, Wong D, Demple B. Interaction of human apurinic endonuclease and DNA polymerase beta in the base excision repair pathway. Proc Natl Acad Sci U S A. 1997 Jul 8;94(14):7166-9. PMID:9207062
↑ Matsumoto Y, Kim K, Katz DS, Feng JA. Catalytic center of DNA polymerase beta for excision of deoxyribose phosphate groups. Biochemistry. 1998 May 5;37(18):6456-64. PMID:9572863 doi:10.1021/bi9727545
↑ DeMott MS, Beyret E, Wong D, Bales BC, Hwang JT, Greenberg MM, Demple B. Covalent trapping of human DNA polymerase beta by the oxidative DNA lesion 2-deoxyribonolactone. J Biol Chem. 2002 Mar 8;277(10):7637-40. Epub 2002 Jan 22. PMID:11805079 doi:10.1074/jbc.C100577200
↑ Parsons JL, Dianova II, Khoronenkova SV, Edelmann MJ, Kessler BM, Dianov GL. USP47 is a deubiquitylating enzyme that regulates base excision repair by controlling steady-state levels of DNA polymerase beta. Mol Cell. 2011 Mar 4;41(5):609-15. doi: 10.1016/j.molcel.2011.02.016. PMID:21362556 doi:10.1016/j.molcel.2011.02.016
↑ Reed AJ, Suo Z. Time-Dependent Extension from an 8-Oxoguanine Lesion by Human DNA Polymerase Beta. J Am Chem Soc. 2017 Jul 19;139(28):9684-9690. doi: 10.1021/jacs.7b05048. Epub, 2017 Jul 6. PMID:28682600 doi:http://dx.doi.org/10.1021/jacs.7b05048

1 Structural highlights
2 Function
3 Publication Abstract from PubMed
4 References

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/5vrx"

@@ Line 3: / Line 3: @@
 <StructureSection load='5vrx' size='340' side='right' caption='[[5vrx]], [[Resolution|resolution]] 2.20&Aring;' scene=''>
 == Structural highlights ==
-<table><tr><td colspan='2'>[[5vrx]] is a 4 chain structure. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=5VRX OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=5VRX FirstGlance]. <br>
+<table><tr><td colspan='2'>[[5vrx]] is a 4 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=5VRX OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=5VRX FirstGlance]. <br>
 </td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=ACT:ACETATE+ION'>ACT</scene>, <scene name='pdbligand=CA:CALCIUM+ION'>CA</scene>, <scene name='pdbligand=IMD:IMIDAZOLE'>IMD</scene>, <scene name='pdbligand=PEG:DI(HYDROXYETHYL)ETHER'>PEG</scene>, <scene name='pdbligand=TTP:THYMIDINE-5-TRIPHOSPHATE'>TTP</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">[[5vry|5vry]], [[5vrz|5vrz]], [[5vs0|5vs0]], [[5vs1|5vs1]], [[5vs2|5vs2]], [[5vs3|5vs3]], [[5vs4|5vs4]]</td></tr>
+<tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">POLB ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=9606 HUMAN])</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=5vrx FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=5vrx OCA], [http://pdbe.org/5vrx PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=5vrx RCSB], [http://www.ebi.ac.uk/pdbsum/5vrx PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=5vrx ProSAT]</span></td></tr>
 </table>
@@ Line 24: / Line 25: @@
 __TOC__
 </StructureSection>
+[[Category: Human]]
 [[Category: Reed, A J]]
 [[Category: Suo, Z]]

5vrx

From Proteopedia

Revision as of 10:30, 22 November 2017

Human DNA polymerase beta pre-catalytic 8-oxoG:dC extension complex with dTTP bound in Watson-Crick conformation

Structural highlights

Function

Publication Abstract from PubMed

References

Contents

Proteopedia Page Contributors and Editors (what is this?)

Views

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