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1t8i

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Revision as of 15:00, 12 October 2017

Human DNA Topoisomerase I (70 Kda) In Complex With The Poison Camptothecin and Covalent Complex With A 22 Base Pair DNA Duplex

Structural highlights

1t8i 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:	1k4t
Gene:	TOP1 (HUMAN)
Activity:	DNA topoisomerase, with EC number 5.99.1.2
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Disease

[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

[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.^[1] ^[2] ^[3] ^[4]

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

Human topoisomerase I (top1) is the molecular target of a diverse set of anticancer compounds, including the camptothecins, indolocarbazoles, and indenoisoquinolines. These compounds bind to a transient top1-DNA covalent complex and inhibit the resealing of a single-strand nick that the enzyme creates to relieve superhelical tension in duplex DNA. (Hertzberg, R. P.; et al. Biochem. 1989, 28, 4629-4638. Hsiang, Y. H.; et al. J. Biol. Chem 1985, 260, 14873-14878. Champoux, J. J. Annu. Rev. Biochem. 2001, 70, 369-413. Stewart, L.; et al. Science 1998, 729, 1534-1541.) We report the X-ray crystal structures of the human top1-DNA complex bound with camptothecin and representative members of the indenoisoquinoline and indolocarbazole classes of top1 poisons. The planar nature of all three structurally diverse classes allows them to intercalate between DNA base pairs at the site of single-strand cleavage. All three classes of compounds have a free electron pair near Arg364, a residue that if mutated confers resistance to all three classes of drugs. The common intercalative binding mode is augmented by unexpected chemotype-specific contacts with amino acid residues Asn352 and Glu356, which adopt alternative side-chain conformations to accommodate the bound compounds. These new X-ray structures explain how very different molecules can stabilize top1-DNA covalent complexes and will aid the rational design of completely novel structural classes of anticancer drugs.

Structures of three classes of anticancer agents bound to the human topoisomerase I-DNA covalent complex.,Staker BL, Feese MD, Cushman M, Pommier Y, Zembower D, Stewart L, Burgin AB J Med Chem. 2005 Apr 7;48(7):2336-45. PMID:15801827^[5]

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

References

↑ D'Arpa P, Machlin PS, Ratrie H 3rd, Rothfield NF, Cleveland DW, Earnshaw WC. cDNA cloning of human DNA topoisomerase I: catalytic activity of a 67.7-kDa carboxyl-terminal fragment. Proc Natl Acad Sci U S A. 1988 Apr;85(8):2543-7. PMID:2833744
↑ Eisenreich A, Bogdanov VY, Zakrzewicz A, Pries A, Antoniak S, Poller W, Schultheiss HP, Rauch U. Cdc2-like kinases and DNA topoisomerase I regulate alternative splicing of tissue factor in human endothelial cells. Circ Res. 2009 Mar 13;104(5):589-99. doi: 10.1161/CIRCRESAHA.108.183905. Epub, 2009 Jan 22. PMID:19168442 doi:10.1161/CIRCRESAHA.108.183905
↑ Interthal H, Quigley PM, Hol WG, Champoux JJ. The role of lysine 532 in the catalytic mechanism of human topoisomerase I. J Biol Chem. 2004 Jan 23;279(4):2984-92. Epub 2003 Oct 31. PMID:14594810 doi:10.1074/jbc.M309959200
↑ Ioanoviciu A, Antony S, Pommier Y, Staker BL, Stewart L, Cushman M. Synthesis and mechanism of action studies of a series of norindenoisoquinoline topoisomerase I poisons reveal an inhibitor with a flipped orientation in the ternary DNA-enzyme-inhibitor complex as determined by X-ray crystallographic analysis. J Med Chem. 2005 Jul 28;48(15):4803-14. PMID:16033260 doi:10.1021/jm050076b
↑ Staker BL, Feese MD, Cushman M, Pommier Y, Zembower D, Stewart L, Burgin AB. Structures of three classes of anticancer agents bound to the human topoisomerase I-DNA covalent complex. J Med Chem. 2005 Apr 7;48(7):2336-45. PMID:15801827 doi:10.1021/jm049146p

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

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/1t8i"

@@ Line 1: / Line 1: @@
 ==Human DNA Topoisomerase I (70 Kda) In Complex With The Poison Camptothecin and Covalent Complex With A 22 Base Pair DNA Duplex==
 <StructureSection load='1t8i' size='340' side='right' caption='[[1t8i]], [[Resolution|resolution]] 3.00&Aring;' scene=''>
@@ Line 8: / Line 9: @@
 <tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">TOP1 ([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_topoisomerase DNA topoisomerase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=5.99.1.2 5.99.1.2] </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=1t8i FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1t8i OCA], [http://pdbe.org/1t8i PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=1t8i RCSB], [http://www.ebi.ac.uk/pdbsum/1t8i PDBsum]</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=1t8i FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1t8i OCA], [http://pdbe.org/1t8i PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=1t8i RCSB], [http://www.ebi.ac.uk/pdbsum/1t8i PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=1t8i ProSAT]</span></td></tr>
 </table>
 == Disease ==
@@ Line 33: / Line 34: @@
 </div>
 <div class="pdbe-citations 1t8i" style="background-color:#fffaf0;"></div>
-==See Also==
-*[[Topoisomerase|Topoisomerase]]
 == References ==
 <references/>

1t8i

From Proteopedia

Revision as of 15:00, 12 October 2017

Human DNA Topoisomerase I (70 Kda) In Complex With The Poison Camptothecin and Covalent Complex With A 22 Base Pair DNA Duplex

Structural highlights

Disease

Function

Evolutionary Conservation

Publication Abstract from PubMed

References

Contents

Proteopedia Page Contributors and Editors (what is this?)

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