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1lpq
From Proteopedia
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<StructureSection load='1lpq' size='340' side='right'caption='[[1lpq]], [[Resolution|resolution]] 3.14Å' scene=''> | <StructureSection load='1lpq' size='340' side='right'caption='[[1lpq]], [[Resolution|resolution]] 3.14Å' scene=''> | ||
== Structural highlights == | == Structural highlights == | ||
| - | <table><tr><td colspan='2'>[[1lpq]] is a 3 chain structure with sequence from [ | + | <table><tr><td colspan='2'>[[1lpq]] is a 3 chain structure with sequence from [https://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1LPQ OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1LPQ FirstGlance]. <br> |
| - | </td></tr><tr id=' | + | </td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 3.14Å</td></tr> |
| - | <tr id=' | + | <tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=8OG:8-OXO-2-DEOXY-GUANOSINE-5-MONOPHOSPHATE'>8OG</scene></td></tr> |
| - | + | <tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=1lpq FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1lpq OCA], [https://pdbe.org/1lpq PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1lpq RCSB], [https://www.ebi.ac.uk/pdbsum/1lpq PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1lpq ProSAT]</span></td></tr> | |
| - | <tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[ | + | |
</table> | </table> | ||
== Disease == | == Disease == | ||
| - | [ | + | [https://www.uniprot.org/uniprot/TOP1_HUMAN TOP1_HUMAN] Note=A chromosomal aberration involving TOP1 is found in a form of therapy-related myelodysplastic syndrome. Translocation t(11;20)(p15;q11) with NUP98. |
== Function == | == Function == | ||
| - | [ | + | [https://www.uniprot.org/uniprot/TOP1_HUMAN TOP1_HUMAN] Releases the supercoiling and torsional tension of DNA introduced during the DNA replication and transcription by transiently cleaving and rejoining one strand of the DNA duplex. Introduces a single-strand break via transesterification at a target site in duplex DNA. The scissile phosphodiester is attacked by the catalytic tyrosine of the enzyme, resulting in the formation of a DNA-(3'-phosphotyrosyl)-enzyme intermediate and the expulsion of a 5'-OH DNA strand. The free DNA strand then undergoes passage around the unbroken strand thus removing DNA supercoils. Finally, in the religation step, the DNA 5'-OH attacks the covalent intermediate to expel the active-site tyrosine and restore the DNA phosphodiester backbone (By similarity). Regulates the alternative splicing of tissue factor (F3) pre-mRNA in endothelial cells.<ref>PMID:2833744</ref> <ref>PMID:19168442</ref> <ref>PMID:14594810</ref> <ref>PMID:16033260</ref> |
== Evolutionary Conservation == | == Evolutionary Conservation == | ||
[[Image:Consurf_key_small.gif|200px|right]] | [[Image:Consurf_key_small.gif|200px|right]] | ||
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</jmol>, as determined by [http://consurfdb.tau.ac.il/ ConSurfDB]. You may read the [[Conservation%2C_Evolutionary|explanation]] of the method and the full data available from [http://bental.tau.ac.il/new_ConSurfDB/main_output.php?pdb_ID=1lpq ConSurf]. | </jmol>, as determined by [http://consurfdb.tau.ac.il/ ConSurfDB]. You may read the [[Conservation%2C_Evolutionary|explanation]] of the method and the full data available from [http://bental.tau.ac.il/new_ConSurfDB/main_output.php?pdb_ID=1lpq ConSurf]. | ||
<div style="clear:both"></div> | <div style="clear:both"></div> | ||
| - | <div style="background-color:#fffaf0;"> | ||
| - | == Publication Abstract from PubMed == | ||
| - | 7,8-Dihydro-8-oxoguanine (8-oxoG) is the most common form of oxidative DNA damage in human cells. Biochemical studies have shown that 8-oxoG decreases the DNA cleavage activity of human topoisomerase I, an enzyme vital to DNA metabolism and stability. We present the 3.1-A crystal structure of human topoisomerase I in noncovalent complex with a DNA oligonucleotide containing 8-oxoG at the +1 position in the scissile strand. We find that 8-oxoG reorganizes the active site of human topoisomerase I into an inactive conformation relative to the structures of topoisomerase I-DNA complexes elucidated previously. The catalytic Tyr-723-Phe rotates away from the DNA cleavage site and packs into the body of the molecule. A second active-site residue, Arg-590, becomes disordered and is not observed in the structure. The docked, inactive conformation of Tyr-723-Phe is reminiscent of the related tyrosine recombinase family of integrases and recombinases, suggesting a common regulatory mechanism. We propose that human topoisomerase I binds to DNA first in an inactive conformation and then rearranges its active site for catalysis. 8-OxoG appears to impact topoisomerase I by stabilizing the inactive, DNA-bound state. | ||
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| - | 8-Oxoguanine rearranges the active site of human topoisomerase I.,Lesher DT, Pommier Y, Stewart L, Redinbo MR Proc Natl Acad Sci U S A. 2002 Sep 17;99(19):12102-7. Epub 2002 Sep 3. PMID:12209008<ref>PMID:12209008</ref> | ||
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| - | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | ||
| - | </div> | ||
| - | <div class="pdbe-citations 1lpq" style="background-color:#fffaf0;"></div> | ||
==See Also== | ==See Also== | ||
| - | *[[Topoisomerase|Topoisomerase]] | + | *[[Topoisomerase 3D structures|Topoisomerase 3D structures]] |
== References == | == References == | ||
<references/> | <references/> | ||
__TOC__ | __TOC__ | ||
</StructureSection> | </StructureSection> | ||
| - | [[Category: | + | [[Category: Homo sapiens]] |
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[[Category: Large Structures]] | [[Category: Large Structures]] | ||
| - | [[Category: Lesher | + | [[Category: Lesher DT]] |
| - | [[Category: Pommier | + | [[Category: Pommier Y]] |
| - | [[Category: Redinbo | + | [[Category: Redinbo MR]] |
| - | [[Category: Stewart | + | [[Category: Stewart L]] |
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Current revision
Human DNA Topoisomerase I (70 Kda) In Non-Covalent Complex With A 22 Base Pair DNA Duplex Containing an 8-oxoG Lesion
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