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1t3n

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Revision as of 04:56, 9 September 2015

Structure of the catalytic core of DNA polymerase Iota in complex with DNA and dTTP

Structural highlights

1t3n 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:
Gene:	POLI (HUMAN)
Resources:	FirstGlance, OCA, RCSB, PDBsum

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]

Evolutionary Conservation

Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.

Publication Abstract from PubMed

Almost all DNA polymerases show a strong preference for incorporating the nucleotide that forms the correct Watson-Crick base pair with the template base. In addition, the catalytic efficiencies with which any given polymerase forms the four possible correct base pairs are roughly the same. Human DNA polymerase-iota (hPoliota), a member of the Y family of DNA polymerases, is an exception to these rules. hPoliota incorporates the correct nucleotide opposite a template adenine with a several hundred to several thousand fold greater efficiency than it incorporates the correct nucleotide opposite a template thymine, whereas its efficiency for correct nucleotide incorporation opposite a template guanine or cytosine is intermediate between these two extremes. Here we present the crystal structure of hPoliota bound to a template primer and an incoming nucleotide. The structure reveals a polymerase that is 'specialized' for Hoogsteen base-pairing, whereby the templating base is driven to the syn conformation. Hoogsteen base-pairing offers a basis for the varied efficiencies and fidelities of hPoliota opposite different template bases, and it provides an elegant mechanism for promoting replication through minor-groove purine adducts that interfere with replication.

Replication by human DNA polymerase-iota occurs by Hoogsteen base-pairing.,Nair DT, Johnson RE, Prakash S, Prakash L, Aggarwal AK Nature. 2004 Jul 15;430(6997):377-80. PMID:15254543^[8]

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

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
↑ 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

1 Structural highlights
2 Function
3 Evolutionary Conservation
4 Publication Abstract from PubMed
5 See Also
6 References

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/1t3n"

@@ Line 2: / Line 2: @@
 <StructureSection load='1t3n' size='340' side='right' caption='[[1t3n]], [[Resolution|resolution]] 2.30&Aring;' scene=''>
 == Structural highlights ==
-<table><tr><td colspan='2'>[[1t3n]] is a 4 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=1T3N OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1T3N FirstGlance]. <br>
+<table><tr><td colspan='2'>[[1t3n]] 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=1T3N OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1T3N FirstGlance]. <br>
 </td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=MG:MAGNESIUM+ION'>MG</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=DOC:2,3-DIDEOXYCYTIDINE-5-MONOPHOSPHATE'>DOC</scene></td></tr>
-<tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">POLI ([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 ([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=1t3n FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1t3n OCA], [http://www.rcsb.org/pdb/explore.do?structureId=1t3n RCSB], [http://www.ebi.ac.uk/pdbsum/1t3n PDBsum]</span></td></tr>
 </table>
@@ Line 35: / Line 35: @@
 __TOC__
 </StructureSection>
-[[Category: Homo sapiens]]
+[[Category: Human]]
 [[Category: Aggarwal, A K]]
 [[Category: Johnson, R E]]

1t3n

From Proteopedia

Revision as of 04:56, 9 September 2015

Structure of the catalytic core of DNA polymerase Iota in complex with DNA and dTTP

Structural highlights

Function

Evolutionary Conservation

Publication Abstract from PubMed

See Also

References

Contents

Proteopedia Page Contributors and Editors (what is this?)

Views

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