This old version of Proteopedia is provided for student assignments while the new version is undergoing repairs. Content and edits done in this old version of Proteopedia after March 1, 2026 will eventually be lost when it is retired in about June of 2026.


Apply for new accounts at the new Proteopedia. Your logins will work in both the old and new versions.


1lpq

From Proteopedia

(Difference between revisions)
Jump to: navigation, search
Current revision (07:34, 14 February 2024) (edit) (undo)
 
(15 intermediate revisions not shown.)
Line 1: Line 1:
-
[[Image:1lpq.gif|left|200px]]
 
-
{{Structure
+
==Human DNA Topoisomerase I (70 Kda) In Non-Covalent Complex With A 22 Base Pair DNA Duplex Containing an 8-oxoG Lesion==
-
|PDB= 1lpq |SIZE=350|CAPTION= <scene name='initialview01'>1lpq</scene>, resolution 3.14&Aring;
+
<StructureSection load='1lpq' size='340' side='right'caption='[[1lpq]], [[Resolution|resolution]] 3.14&Aring;' scene=''>
-
|SITE=
+
== Structural highlights ==
-
|LIGAND=
+
<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>
-
|ACTIVITY= [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]
+
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 3.14&#8491;</td></tr>
-
|GENE=
+
<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>
 +
</table>
 +
== 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 ==
 +
[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 ==
 +
[[Image:Consurf_key_small.gif|200px|right]]
 +
Check<jmol>
 +
<jmolCheckbox>
 +
<scriptWhenChecked>; select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/lp/1lpq_consurf.spt"</scriptWhenChecked>
 +
<scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked>
 +
<text>to colour the structure by Evolutionary Conservation</text>
 +
</jmolCheckbox>
 +
</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>
-
'''Human DNA Topoisomerase I (70 Kda) In Non-Covalent Complex With A 22 Base Pair DNA Duplex Containing an 8-oxoG Lesion'''
+
==See Also==
-
 
+
*[[Topoisomerase 3D structures|Topoisomerase 3D structures]]
-
 
+
== References ==
-
==Overview==
+
<references/>
-
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.
+
__TOC__
-
 
+
</StructureSection>
-
==Disease==
+
-
Known disease associated with this structure: DNA topoisomerase I, camptothecin-resistant OMIM:[[http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=126420 126420]]
+
-
 
+
-
==About this Structure==
+
-
1LPQ is a [[Single protein]] structure of 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=1LPQ OCA].
+
-
 
+
-
==Reference==
+
-
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:[http://www.ncbi.nlm.nih.gov/pubmed/12209008 12209008]
+
-
[[Category: DNA topoisomerase]]
+
[[Category: Homo sapiens]]
[[Category: Homo sapiens]]
-
[[Category: Single protein]]
+
[[Category: Large Structures]]
-
[[Category: Lesher, D T.]]
+
[[Category: Lesher DT]]
-
[[Category: Pommier, Y.]]
+
[[Category: Pommier Y]]
-
[[Category: Redinbo, M R.]]
+
[[Category: Redinbo MR]]
-
[[Category: Stewart, L.]]
+
[[Category: Stewart L]]
-
[[Category: dna damage]]
+
-
[[Category: induced conformational change]]
+
-
[[Category: protein-dna complex]]
+
-
 
+
-
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Mar 20 12:33:41 2008''
+

Current revision

Human DNA Topoisomerase I (70 Kda) In Non-Covalent Complex With A 22 Base Pair DNA Duplex Containing an 8-oxoG Lesion

PDB ID 1lpq

Drag the structure with the mouse to rotate

Proteopedia Page Contributors and Editors (what is this?)

OCA

Personal tools