View source for 5nwa


==Crystal structure of the complex of Tdp1 with duplex DNA==
<StructureSection load='5nwa' size='340' side='right'caption='[[5nwa]], [[Resolution|resolution]] 3.20&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[5nwa]] is a 3 chain structure with sequence from [https://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens] and [https://en.wikipedia.org/wiki/Synthetic_construct Synthetic construct]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=5NWA OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=5NWA FirstGlance]. <br>
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 3.2&#8491;</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=5nwa FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=5nwa OCA], [https://pdbe.org/5nwa PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=5nwa RCSB], [https://www.ebi.ac.uk/pdbsum/5nwa PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=5nwa ProSAT]</span></td></tr>
</table>
== Disease ==
[https://www.uniprot.org/uniprot/TYDP1_HUMAN TYDP1_HUMAN] Defects in TDP1 are the cause of spinocerebellar ataxia autosomal recessive with axonal neuropathy (SCAN1) [MIM:[https://omim.org/entry/607250 607250]. SCAN1 is an autosomal recessive cerebellar ataxia (ARCA) associated with peripheral axonal motor and sensory neuropathy, distal muscular atrophy, pes cavus and steppage gait as seen in Charcot-Marie-Tooth neuropathy. All affected individuals have normal intelligence.<ref>PMID:16141202</ref> <ref>PMID:15647511</ref> <ref>PMID:12244316</ref> <ref>PMID:17948061</ref> <ref>PMID:15920477</ref> 
== Function ==
[https://www.uniprot.org/uniprot/TYDP1_HUMAN TYDP1_HUMAN] DNA repair enzyme that can remove a variety of covalent adducts from DNA through hydrolysis of a 3'-phosphodiester bond, giving rise to DNA with a free 3' phosphate. Catalyzes the hydrolysis of dead-end complexes between DNA and the topoisomerase I active site tyrosine residue. Hydrolyzes 3'-phosphoglycolates on protruding 3' ends on DNA double-strand breaks due to DNA damage by radiation and free radicals. Acts on blunt-ended double-strand DNA breaks and on single-stranded DNA. Has low 3'exonuclease activity and can remove a single nucleoside from the 3'end of DNA and RNA molecules with 3'hydroxyl groups. Has no exonuclease activity towards DNA or RNA with a 3'phosphate.<ref>PMID:12023295</ref> <ref>PMID:15111055</ref> <ref>PMID:15811850</ref> <ref>PMID:16141202</ref> <ref>PMID:22822062</ref> 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Tyrosyl-DNA phosphodiesterase (Tdp1) is a DNA 3'-end processing enzyme that repairs topoisomerase 1B-induced DNA damage. We use a new tool combining site-specific DNA-protein cross-linking with mass spectrometry to identify Tdp1 interactions with DNA. A conserved phenylalanine (F259) of Tdp1, required for efficient DNA processing in biochemical assays, cross-links to defined positions in DNA substrates. Crystal structures of Tdp1-DNA complexes capture the DNA repair machinery after 3'-end cleavage; these reveal how Tdp1 coordinates the 3'-phosphorylated product of nucleosidase activity and accommodates duplex DNA. A hydrophobic wedge splits the DNA ends, directing the scissile strand through a channel towards the active site. The F259 side-chain stacks against the -3 base pair, delimiting the junction of duplexed and melted DNA, and fixes the scissile strand in the channel. Our results explain why Tdp1 cleavage is non-processive and provide a molecular basis for DNA 3'-end processing by Tdp1.

Structural basis for DNA 3'-end processing by human tyrosyl-DNA phosphodiesterase 1.,Flett FJ, Ruksenaite E, Armstrong LA, Bharati S, Carloni R, Morris ER, Mackay CL, Interthal H, Richardson JM Nat Commun. 2018 Jan 2;9(1):24. doi: 10.1038/s41467-017-02530-z. PMID:29295983<ref>PMID:29295983</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 5nwa" style="background-color:#fffaf0;"></div>

==See Also==
*[[Phosphodiesterase 3D structures|Phosphodiesterase 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Homo sapiens]]
[[Category: Large Structures]]
[[Category: Synthetic construct]]
[[Category: Morris ER]]
[[Category: Richardson JM]]
[[Category: Ruksenaite E]]