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5eaw

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Revision as of 06:51, 22 April 2020

Crystal structure of Dna2 nuclease-helicase

Structural highlights

5eaw is a 2 chain structure with sequence from Lk3 transgenic mice. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Ligands:	,
Related:	5ean, 5eax, 5eay
Gene:	Dna2, Dna2l, Kiaa0083 (LK3 transgenic mice)
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

[DNA2_MOUSE] Key enzyme involved in DNA replication and DNA repair in nucleus and mitochondrion. Involved in Okazaki fragments processing by cleaving long flaps that escape FEN1: flaps that are longer than 27 nucleotides are coated by replication protein A complex (RPA), leading to recruit DNA2 which cleaves the flap until it is too short to bind RPA and becomes a substrate for FEN1. Also involved in 5'-end resection of DNA during double-strand break (DSB) repair: recruited by BLM and mediates the cleavage of 5'-ssDNA, while the 3'-ssDNA cleavage is prevented by the presence of RPA. Also involved in DNA replication checkpoint independently of Okazaki fragments processing. Possesses different enzymatic activities, such as single-stranded DNA (ssDNA)-dependent ATPase, 5'-3' helicase and endonuclease activities. While the ATPase and endonuclease activities are well-defined and play a key role in Okazaki fragments processing and DSB repair, the 5'-3' DNA helicase activity is subject to debate. According to various reports, the helicase activity is weak and its function remains largely unclear. Helicase activity may promote the motion of DNA2 on the flap, helping the nuclease function (By similarity).

Publication Abstract from PubMed

The Dna2 nuclease-helicase maintains genomic integrity by processing DNA double-strand breaks, Okazaki fragments and stalled replication forks. Dna2 requires ssDNA ends, and is dependent on the ssDNA-binding protein Rpa, which controls cleavage polarity. Here we present the 2.3 A structure of intact mouse Dna2 bound to a 15-nucleotide ssDNA. The nuclease active site is embedded in a long, narrow tunnel through which the DNA has to thread. The helicase domain is required for DNA binding but not threading. We also present the structure of a flexibly-tethered Dna2-Rpa interaction that recruits Dna2 to Rpa-coated DNA. We establish that a second Dna2-Rpa interaction is mutually exclusive with Rpa-DNA interactions and mediates the displacement of Rpa from ssDNA. This interaction occurs at the nuclease tunnel entrance and the 5' end of the Rpa-DNA complex. Hence, it only displaces Rpa from the 5' but not 3' end, explaining how Rpa regulates cleavage polarity.

Dna2 nuclease-helicase structure, mechanism and regulation by Rpa.,Zhou C, Pourmal S, Pavletich NP Elife. 2015 Oct 22;4. pii: e09832. doi: 10.7554/eLife.09832. PMID:26491943^[1]

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

References

↑ Zhou C, Pourmal S, Pavletich NP. Dna2 nuclease-helicase structure, mechanism and regulation by Rpa. Elife. 2015 Oct 22;4. pii: e09832. doi: 10.7554/eLife.09832. PMID:26491943 doi:http://dx.doi.org/10.7554/eLife.09832

1 Structural highlights
2 Function
3 Publication Abstract from PubMed
4 References

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/5eaw"

@@ Line 1: / Line 1: @@
 ==Crystal structure of Dna2 nuclease-helicase==
-<StructureSection load='5eaw' size='340' side='right' caption='[[5eaw]], [[Resolution|resolution]] 3.00&Aring;' scene=''>
+<StructureSection load='5eaw' size='340' side='right'caption='[[5eaw]], [[Resolution|resolution]] 3.00&Aring;' scene=''>
 == Structural highlights ==
-<table><tr><td colspan='2'>[[5eaw]] is a 2 chain structure. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=5EAW OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=5EAW FirstGlance]. <br>
+<table><tr><td colspan='2'>[[5eaw]] is a 2 chain structure with sequence from [http://en.wikipedia.org/wiki/Lk3_transgenic_mice Lk3 transgenic mice]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=5EAW OCA]. For a <b>guided tour on the structure components</b> use [http://proteopedia.org/fgij/fg.htm?mol=5EAW FirstGlance]. <br>
-</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=ADP:ADENOSINE-5-DIPHOSPHATE'>ADP</scene>, <scene name='pdbligand=SF4:IRON/SULFUR+CLUSTER'>SF4</scene></td></tr>
+</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=ADP:ADENOSINE-5-DIPHOSPHATE'>ADP</scene>, <scene name='pdbligand=SF4:IRON/SULFUR+CLUSTER'>SF4</scene></td></tr>
 <tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[5ean|5ean]], [[5eax|5eax]], [[5eay|5eay]]</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=5eaw FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=5eaw OCA], [http://pdbe.org/5eaw PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=5eaw RCSB], [http://www.ebi.ac.uk/pdbsum/5eaw PDBsum]</span></td></tr>
+<tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">Dna2, Dna2l, Kiaa0083 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=10090 LK3 transgenic mice])</td></tr>
+<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://proteopedia.org/fgij/fg.htm?mol=5eaw FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=5eaw OCA], [http://pdbe.org/5eaw PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=5eaw RCSB], [http://www.ebi.ac.uk/pdbsum/5eaw PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=5eaw ProSAT]</span></td></tr>
 </table>
 == Function ==
@@ Line 22: / Line 24: @@
 __TOC__
 </StructureSection>
+[[Category: Large Structures]]
+[[Category: Lk3 transgenic mice]]
 [[Category: Pavletich, N P]]
 [[Category: Pourmal, S]]

5eaw

From Proteopedia

Revision as of 06:51, 22 April 2020

Crystal structure of Dna2 nuclease-helicase

Structural highlights

Function

Publication Abstract from PubMed

References

Contents

Proteopedia Page Contributors and Editors (what is this?)

Views

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