7z03
From Proteopedia
(Difference between revisions)
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== Structural highlights == | == Structural highlights == | ||
<table><tr><td colspan='2'>[[7z03]] is a 6 chain structure with sequence from [https://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli] 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=7Z03 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=7Z03 FirstGlance]. <br> | <table><tr><td colspan='2'>[[7z03]] is a 6 chain structure with sequence from [https://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli] 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=7Z03 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=7Z03 FirstGlance]. <br> | ||
| - | </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=MG:MAGNESIUM+ION'>MG</scene>, <scene name='pdbligand=MN:MANGANESE+(II)+ION'>MN</scene></td></tr> | + | </td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">Electron Microscopy, [[Resolution|Resolution]] 3.7Å</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=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=7z03 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=7z03 OCA], [https://pdbe.org/7z03 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=7z03 RCSB], [https://www.ebi.ac.uk/pdbsum/7z03 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=7z03 ProSAT]</span></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=7z03 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=7z03 OCA], [https://pdbe.org/7z03 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=7z03 RCSB], [https://www.ebi.ac.uk/pdbsum/7z03 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=7z03 ProSAT]</span></td></tr> | ||
</table> | </table> | ||
== Function == | == Function == | ||
| - | + | [https://www.uniprot.org/uniprot/SBCC_ECOLI SBCC_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. | |
<div style="background-color:#fffaf0;"> | <div style="background-color:#fffaf0;"> | ||
== Publication Abstract from PubMed == | == Publication Abstract from PubMed == | ||
DNA double-strand breaks (DSBs) threaten genome stability and are linked to tumorigenesis in humans. Repair of DSBs requires the removal of attached proteins and hairpins through a poorly understood but physiologically critical endonuclease activity by the Mre11-Rad50 complex. Here, we report cryoelectron microscopy (cryo-EM) structures of the bacterial Mre11-Rad50 homolog SbcCD bound to a protein-blocked DNA end and a DNA hairpin. The structures reveal that Mre11-Rad50 bends internal DNA for endonucleolytic cleavage and show how internal DNA, DNA ends, and hairpins are processed through a similar ATP-regulated conformational state. Furthermore, Mre11-Rad50 is loaded onto blocked DNA ends with Mre11 pointing away from the block, explaining the distinct biochemistries of 3' --> 5' exonucleolytic and endonucleolytic incision through the way Mre11-Rad50 interacts with diverse DNA ends. In summary, our results unify Mre11-Rad50's enigmatic nuclease diversity within a single structural framework and reveal how blocked DNA ends and hairpins are processed. | DNA double-strand breaks (DSBs) threaten genome stability and are linked to tumorigenesis in humans. Repair of DSBs requires the removal of attached proteins and hairpins through a poorly understood but physiologically critical endonuclease activity by the Mre11-Rad50 complex. Here, we report cryoelectron microscopy (cryo-EM) structures of the bacterial Mre11-Rad50 homolog SbcCD bound to a protein-blocked DNA end and a DNA hairpin. The structures reveal that Mre11-Rad50 bends internal DNA for endonucleolytic cleavage and show how internal DNA, DNA ends, and hairpins are processed through a similar ATP-regulated conformational state. Furthermore, Mre11-Rad50 is loaded onto blocked DNA ends with Mre11 pointing away from the block, explaining the distinct biochemistries of 3' --> 5' exonucleolytic and endonucleolytic incision through the way Mre11-Rad50 interacts with diverse DNA ends. In summary, our results unify Mre11-Rad50's enigmatic nuclease diversity within a single structural framework and reveal how blocked DNA ends and hairpins are processed. | ||
| - | Structural mechanism of endonucleolytic processing of blocked DNA ends and hairpins by Mre11-Rad50.,Gut F, Kashammer L, Lammens K, Bartho JD, Boggusch AM, van de Logt E, Kessler B, Hopfner KP Mol Cell. 2022 | + | Structural mechanism of endonucleolytic processing of blocked DNA ends and hairpins by Mre11-Rad50.,Gut F, Kashammer L, Lammens K, Bartho JD, Boggusch AM, van de Logt E, Kessler B, Hopfner KP Mol Cell. 2022 Sep 15;82(18):3513-3522.e6. doi: 10.1016/j.molcel.2022.07.019. , Epub 2022 Aug 19. PMID:35987200<ref>PMID:35987200</ref> |
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | ||
Current revision
Endonuclease state of the E. coli Mre11-Rad50 (SbcCD) head complex bound to ADP and extended dsDNA
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