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5l1k

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Revision as of 18:35, 15 November 2017

PostInsertion complex of Human DNA Polymerase Eta bypassing an O6-Methyl-2'-deoxyguanosine : dC site

Structural highlights

5l1k 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:	5l1l, 5l1j, 5l1i
Gene:	POLH, RAD30, RAD30A, XPV (HUMAN)
Activity:	DNA-directed DNA polymerase, with EC number 2.7.7.7
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Disease

[POLH_HUMAN] Defects in POLH are the cause of xeroderma pigmentosum variant type (XPV) [MIM:278750]; also designated as XP-V. Xeroderma pigmentosum (XP) is an autosomal recessive disease due to deficient nucleotide excision repair. It is characterized by hypersensitivity of the skin to sunlight, followed by high incidence of skin cancer and frequent neurologic abnormalities. XPV shows normal nucleotide excision repair, but an exaggerated delay in recovery of replicative DNA synthesis. Most XPV patients do not develop clinical symptoms and skin neoplasias until a later age. Clinical manifestations are limited to photo-induced deterioration of the skin and eyes.^[1] ^[2] ^[3] ^[4] ^[5]

Function

[POLH_HUMAN] 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. Plays an important role in the repair of UV-induced pyrimidine dimers. Depending on the context, it inserts the correct base, but causes frequent base transitions and transversions. May play a role in hypermutation at immunoglobulin genes. Forms a Schiff base with 5'-deoxyribose phosphate at abasic sites, but does not have lyase activity. Targets POLI to replication foci.^[6] ^[7] ^[8] ^[9] ^[10]

Publication Abstract from PubMed

O6-Methyl-2(prime)-deoxyguanosine (O6-MeG) is a ubiquitous DNA lesion, formed not only by xenobiotic carcinogens but also by the endogenous methylating agent S-adenosylmethionine. It can introduce mutations during DNA replication, with different DNA polymerases displaying different ratios of correct or incorrect incoporation opposite this nucleoside. Of the "translesion" Y-family human DNA polymerases (hpols), hpol eta is most efficient in incorporating equal numbers of correct and incorrect C and T bases. However, the mechanistic basis for this specific yet indescriminate activity is not known. To explore this question, we report biochemical and structural analysis of the catalytic core of hpol eta. Activity assays showed the truncated form displayed similar misincorporation properties as the full-length enzyme, incorporating C and T equally and extending from both. X-ray crystal structures of both dC and dT paired with O6-MeG were solved, in both insertion and extension modes. The structures revealed a Watson-Crick-like pairing between O6-MeG and dTMPNPP (approximating dT) at both the insertion and extension stages with formation of two H-bonds. Conversely, both the structures with O6-MeG opposite dCTP and dC display sheared configuration of base pairs, but to different degrees, with formation of two bifurcated H-bonds and two single H-bonds in the structures trapped in the insertion and extension states, respectively. The structural data are consistent with the observed tendency of hpol eta to insert both dC and dT opposite the O6-MeG lesion with similar efficiencies. Comparison of the hpol eta active site configurations with either O6-MeG:dC or O6-MeG:dT bound compared to the corresponding situations in structures of complexes of Sulfolobus solfataricus Dpo4, a bypass pol that favors C relative to T by a factor of ~4, helps rationalize the more error-prone synthesis opposite the lesion by hpol eta.

Mechanisms of Insertion of dCTP and dTTP Opposite the DNA lesion O6-Methyl-2'-deoxyguanosine by Human DNA Polymerase eta.,Patra A, Zhang Q, Guengerich FP, Egli M J Biol Chem. 2016 Sep 30. pii: jbc.M116.755462. PMID:27694439^[11]

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

References

↑ Masutani C, Kusumoto R, Yamada A, Dohmae N, Yokoi M, Yuasa M, Araki M, Iwai S, Takio K, Hanaoka F. The XPV (xeroderma pigmentosum variant) gene encodes human DNA polymerase eta. Nature. 1999 Jun 17;399(6737):700-4. PMID:10385124 doi:10.1038/21447
↑ Johnson RE, Kondratick CM, Prakash S, Prakash L. hRAD30 mutations in the variant form of xeroderma pigmentosum. Science. 1999 Jul 9;285(5425):263-5. PMID:10398605
↑ Yuasa M, Masutani C, Eki T, Hanaoka F. Genomic structure, chromosomal localization and identification of mutations in the xeroderma pigmentosum variant (XPV) gene. Oncogene. 2000 Sep 28;19(41):4721-8. PMID:11032022 doi:10.1038/sj.onc.1203842
↑ Itoh T, Linn S, Kamide R, Tokushige H, Katori N, Hosaka Y, Yamaizumi M. Xeroderma pigmentosum variant heterozygotes show reduced levels of recovery of replicative DNA synthesis in the presence of caffeine after ultraviolet irradiation. J Invest Dermatol. 2000 Dec;115(6):981-5. PMID:11121129 doi:10.1046/j.1523-1747.2000.00154.x
↑ Broughton BC, Cordonnier A, Kleijer WJ, Jaspers NG, Fawcett H, Raams A, Garritsen VH, Stary A, Avril MF, Boudsocq F, Masutani C, Hanaoka F, Fuchs RP, Sarasin A, Lehmann AR. Molecular analysis of mutations in DNA polymerase eta in xeroderma pigmentosum-variant patients. Proc Natl Acad Sci U S A. 2002 Jan 22;99(2):815-20. Epub 2002 Jan 2. PMID:11773631 doi:10.1073/pnas.022473899
↑ Masutani C, Kusumoto R, Yamada A, Dohmae N, Yokoi M, Yuasa M, Araki M, Iwai S, Takio K, Hanaoka F. The XPV (xeroderma pigmentosum variant) gene encodes human DNA polymerase eta. Nature. 1999 Jun 17;399(6737):700-4. PMID:10385124 doi:10.1038/21447
↑ Glick E, Vigna KL, Loeb LA. Mutations in human DNA polymerase eta motif II alter bypass of DNA lesions. EMBO J. 2001 Dec 17;20(24):7303-12. PMID:11743006 doi:10.1093/emboj/20.24.7303
↑ Zeng X, Winter DB, Kasmer C, Kraemer KH, Lehmann AR, Gearhart PJ. DNA polymerase eta is an A-T mutator in somatic hypermutation of immunoglobulin variable genes. Nat Immunol. 2001 Jun;2(6):537-41. PMID:11376341 doi:10.1038/88740
↑ 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
↑ Faili A, Aoufouchi S, Weller S, Vuillier F, Stary A, Sarasin A, Reynaud CA, Weill JC. DNA polymerase eta is involved in hypermutation occurring during immunoglobulin class switch recombination. J Exp Med. 2004 Jan 19;199(2):265-70. PMID:14734526 doi:10.1084/jem.20031831
↑ Patra A, Zhang Q, Guengerich FP, Egli M. Mechanisms of Insertion of dCTP and dTTP Opposite the DNA lesion O6-Methyl-2'-deoxyguanosine by Human DNA Polymerase eta. J Biol Chem. 2016 Sep 30. pii: jbc.M116.755462. PMID:27694439 doi:http://dx.doi.org/10.1074/jbc.M116.755462

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

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/5l1k"

@@ Line 3: / Line 3: @@
 <StructureSection load='5l1k' size='340' side='right' caption='[[5l1k]], [[Resolution|resolution]] 1.82&Aring;' scene=''>
 == Structural highlights ==
-<table><tr><td colspan='2'>[[5l1k]] is a 3 chain structure. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=5L1K OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=5L1K FirstGlance]. <br>
+<table><tr><td colspan='2'>[[5l1k]] 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=5L1K OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=5L1K FirstGlance]. <br>
 </td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=0KX:2-DEOXY-5-O-[(R)-HYDROXY{[(R)-HYDROXY(PHOSPHONOOXY)PHOSPHORYL]AMINO}PHOSPHORYL]CYTIDINE'>0KX</scene>, <scene name='pdbligand=GOL:GLYCEROL'>GOL</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=6OG:6-O-METHYL+GUANOSINE-5-MONOPHOSPHATE'>6OG</scene></td></tr>
 <tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[5l1l|5l1l]], [[5l1j|5l1j]], [[5l1i|5l1i]]</td></tr>
+<tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">POLH, RAD30, RAD30A, XPV ([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='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=5l1k FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=5l1k OCA], [http://pdbe.org/5l1k PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=5l1k RCSB], [http://www.ebi.ac.uk/pdbsum/5l1k PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=5l1k ProSAT]</span></td></tr>
@@ Line 28: / Line 29: @@
 </StructureSection>
 [[Category: DNA-directed DNA polymerase]]
+[[Category: Human]]
 [[Category: Egli, M]]
 [[Category: Patra, A]]

5l1k

From Proteopedia

Revision as of 18:35, 15 November 2017

PostInsertion complex of Human DNA Polymerase Eta bypassing an O6-Methyl-2'-deoxyguanosine : dC site

Structural highlights

Disease

Function

Publication Abstract from PubMed

References

Contents

Proteopedia Page Contributors and Editors (what is this?)

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