4rzr: Difference between revisions
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''' | ==Bypass of a bulky adduct dG1,8 by DPO4== | ||
<StructureSection load='4rzr' size='340' side='right' caption='[[4rzr]], [[Resolution|resolution]] 2.20Å' scene=''> | |||
== Structural highlights == | |||
<table><tr><td colspan='2'>[[4rzr]] is a 6 chain structure. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4RZR OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=4RZR FirstGlance]. <br> | |||
</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=CA:CALCIUM+ION'>CA</scene>, <scene name='pdbligand=DCP:2-DEOXYCYTIDINE-5-TRIPHOSPHATE'>DCP</scene>, <scene name='pdbligand=GOL:GLYCEROL'>GOL</scene>, <scene name='pdbligand=NA:SODIUM+ION'>NA</scene>, <scene name='pdbligand=TRS:2-AMINO-2-HYDROXYMETHYL-PROPANE-1,3-DIOL'>TRS</scene></td></tr> | |||
<tr id='NonStdRes'><td class="sblockLbl"><b>[[Non-Standard_Residue|NonStd Res:]]</b></td><td class="sblockDat"><scene name='pdbligand=2JV:N-(8-AMINOPYREN-1-YL)-2-DEOXY-5-O-(TRIHYDROXY-LAMBDA~5~-PHOSPHANYL)GUANOSINE'>2JV</scene></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=4rzr FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4rzr OCA], [http://pdbe.org/4rzr PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=4rzr RCSB], [http://www.ebi.ac.uk/pdbsum/4rzr PDBsum]</span></td></tr> | |||
</table> | |||
== Function == | |||
[[http://www.uniprot.org/uniprot/DPO4_SULSO DPO4_SULSO]] Poorly processive, error-prone DNA polymerase involved in untargeted mutagenesis. Copies undamaged DNA at stalled replication forks, which arise in vivo from mismatched or misaligned primer ends. These misaligned primers can be extended by PolIV. Exhibits no 3'-5' exonuclease (proofreading) activity. It is involved in translesional synthesis.[HAMAP-Rule:MF_01113] | |||
<div style="background-color:#fffaf0;"> | |||
== Publication Abstract from PubMed == | |||
1-Nitropyrene (1-NP), an environmental pollutant, induces DNA damage in vivo and is considered to be carcinogenic. The DNA adducts formed by the 1-NP metabolites stall replicative DNA polymerases but are presumably bypassed by error-prone Y-family DNA polymerases at the expense of replication fidelity and efficiency in vivo. Our running start assays confirmed that a site-specifically placed 8-(deoxyguanosin-N(2)-yl)-1-aminopyrene (dG(1,8)), one of the DNA adducts derived from 1-NP, can be bypassed by Sulfolobus solfataricus DNA polymerase IV (Dpo4), although this representative Y-family enzyme was paused strongly by the lesion. Pre-steady-state kinetic assays were employed to determine the low nucleotide incorporation fidelity and establish a minimal kinetic mechanism for the dG(1,8) bypass by Dpo4. To reveal a structural basis for dCTP incorporation opposite dG(1,8), we solved the crystal structures of the complexes of Dpo4 and DNA containing a templating dG(1,8) lesion in the absence or presence of dCTP. The Dpo4.DNA-dG(1,8) binary structure shows that the aminopyrene moiety of the lesion stacks against the primer/template junction pair, while its dG moiety projected into the cleft between the Finger and Little Finger domains of Dpo4. In the Dpo4.DNA-dG(1,8).dCTP ternary structure, the aminopyrene moiety of the dG(1,8) lesion, is sandwiched between the nascent and junction base pairs, while its base is present in the major groove. Moreover, dCTP forms a Watson-Crick base pair with dG, two nucleotides upstream from the dG(1,8) site, creating a complex for "-2" frameshift mutation. Mechanistically, these crystal structures provide additional insight into the aforementioned minimal kinetic mechanism. | |||
Mechanistic Basis for the Bypass of a Bulky DNA Adduct Catalyzed by a Y-Family DNA Polymerase.,Vyas R, Efthimiopoulos G, Tokarsky EJ, Malik CK, Basu AK, Suo Z J Am Chem Soc. 2015 Sep 23;137(37):12131-42. doi: 10.1021/jacs.5b08027. Epub 2015, Sep 11. PMID:26327169<ref>PMID:26327169</ref> | |||
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |||
</div> | |||
<div class="pdbe-citations 4rzr" style="background-color:#fffaf0;"></div> | |||
[[Category: | == References == | ||
<references/> | |||
__TOC__ | |||
</StructureSection> | |||
[[Category: DNA-directed DNA polymerase]] | |||
[[Category: Suo, Z]] | [[Category: Suo, Z]] | ||
[[Category: Vyas, R]] | [[Category: Vyas, R]] | ||
[[Category: Dbh]] | |||
[[Category: Dpo4]] | |||
[[Category: Polymerase]] | |||
[[Category: Transferase-dna complex]] | |||
Revision as of 10:34, 7 October 2015
Bypass of a bulky adduct dG1,8 by DPO4Bypass of a bulky adduct dG1,8 by DPO4
Structural highlights
Function[DPO4_SULSO] Poorly processive, error-prone DNA polymerase involved in untargeted mutagenesis. Copies undamaged DNA at stalled replication forks, which arise in vivo from mismatched or misaligned primer ends. These misaligned primers can be extended by PolIV. Exhibits no 3'-5' exonuclease (proofreading) activity. It is involved in translesional synthesis.[HAMAP-Rule:MF_01113] Publication Abstract from PubMed1-Nitropyrene (1-NP), an environmental pollutant, induces DNA damage in vivo and is considered to be carcinogenic. The DNA adducts formed by the 1-NP metabolites stall replicative DNA polymerases but are presumably bypassed by error-prone Y-family DNA polymerases at the expense of replication fidelity and efficiency in vivo. Our running start assays confirmed that a site-specifically placed 8-(deoxyguanosin-N(2)-yl)-1-aminopyrene (dG(1,8)), one of the DNA adducts derived from 1-NP, can be bypassed by Sulfolobus solfataricus DNA polymerase IV (Dpo4), although this representative Y-family enzyme was paused strongly by the lesion. Pre-steady-state kinetic assays were employed to determine the low nucleotide incorporation fidelity and establish a minimal kinetic mechanism for the dG(1,8) bypass by Dpo4. To reveal a structural basis for dCTP incorporation opposite dG(1,8), we solved the crystal structures of the complexes of Dpo4 and DNA containing a templating dG(1,8) lesion in the absence or presence of dCTP. The Dpo4.DNA-dG(1,8) binary structure shows that the aminopyrene moiety of the lesion stacks against the primer/template junction pair, while its dG moiety projected into the cleft between the Finger and Little Finger domains of Dpo4. In the Dpo4.DNA-dG(1,8).dCTP ternary structure, the aminopyrene moiety of the dG(1,8) lesion, is sandwiched between the nascent and junction base pairs, while its base is present in the major groove. Moreover, dCTP forms a Watson-Crick base pair with dG, two nucleotides upstream from the dG(1,8) site, creating a complex for "-2" frameshift mutation. Mechanistically, these crystal structures provide additional insight into the aforementioned minimal kinetic mechanism. Mechanistic Basis for the Bypass of a Bulky DNA Adduct Catalyzed by a Y-Family DNA Polymerase.,Vyas R, Efthimiopoulos G, Tokarsky EJ, Malik CK, Basu AK, Suo Z J Am Chem Soc. 2015 Sep 23;137(37):12131-42. doi: 10.1021/jacs.5b08027. Epub 2015, Sep 11. PMID:26327169[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
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