View source for 6s6v


==Resting state of the E. coli Mre11-Rad50 (SbcCD) head complex bound to ATPgS==
<SX load='6s6v' size='340' side='right' viewer='molstar' caption='[[6s6v]], [[Resolution|resolution]] 3.50&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[6s6v]] is a 4 chain structure with sequence from [https://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=6S6V OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=6S6V FirstGlance]. <br>
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">Electron Microscopy, [[Resolution|Resolution]] 3.5&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=AGS:PHOSPHOTHIOPHOSPHORIC+ACID-ADENYLATE+ESTER'>AGS</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene>, <scene name='pdbligand=MN:MANGANESE+(II)+ION'>MN</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=6s6v FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=6s6v OCA], [https://pdbe.org/6s6v PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=6s6v RCSB], [https://www.ebi.ac.uk/pdbsum/6s6v PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=6s6v ProSAT]</span></td></tr>
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== Function ==
[https://www.uniprot.org/uniprot/SBCD_ECOLI SBCD_ECOLI] SbcCD cleaves DNA hairpin structures. These structures can inhibit DNA replication and are intermediates in certain DNA recombination reactions. The complex acts as a 3'->5' double strand exonuclease that can open hairpins. It also has a 5' single-strand endonuclease activity.
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== Publication Abstract from PubMed ==
DNA double-strand breaks (DSBs) threaten genome stability throughout life and are linked to tumorigenesis in humans. To initiate DSB repair by end joining or homologous recombination, the Mre11-nuclease Rad50-ATPase complex detects and processes diverse and obstructed DNA ends, but a structural mechanism is still lacking. Here we report cryo-EM structures of the E. coli Mre11-Rad50 homolog SbcCD in resting and DNA-bound cutting states. In the resting state, Mre11's nuclease is blocked by ATP-Rad50, and the Rad50 coiled coils appear flexible. Upon DNA binding, the two coiled coils zip up into a rod and, together with the Rad50 nucleotide-binding domains, form a clamp around dsDNA. Mre11 moves to the side of Rad50, binds the DNA end, and assembles a DNA cutting channel for the nuclease reactions. The structures reveal how Mre11-Rad50 can detect and process diverse DNA ends and uncover a clamping and gating function for the coiled coils.

Mechanism of DNA End Sensing and Processing by the Mre11-Rad50 Complex.,Kashammer L, Saathoff JH, Lammens K, Gut F, Bartho J, Alt A, Kessler B, Hopfner KP Mol Cell. 2019 Nov 7;76(3):382-394.e6. doi: 10.1016/j.molcel.2019.07.035. Epub, 2019 Sep 3. PMID:31492634<ref>PMID:31492634</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
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<div class="pdbe-citations 6s6v" style="background-color:#fffaf0;"></div>
== References ==
<references/>
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[[Category: Escherichia coli]]
[[Category: Large Structures]]
[[Category: Alt A]]
[[Category: Bartho J]]
[[Category: Gut F]]
[[Category: Hopfner KP]]
[[Category: Kaeshammer L]]
[[Category: Kessler B]]
[[Category: Lammens K]]
[[Category: Saathoff JH]]