View source for 7qen


==S.c. Condensin core in DNA- and ATP-bound state==
<StructureSection load='7qen' size='340' side='right'caption='[[7qen]], [[Resolution|resolution]] 3.46&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[7qen]] is a 6 chain structure with sequence from [https://en.wikipedia.org/wiki/Saccharomyces_cerevisiae Saccharomyces cerevisiae], [https://en.wikipedia.org/wiki/Saccharomyces_cerevisiae_CEN.PK113-7D Saccharomyces cerevisiae CEN.PK113-7D] 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=7QEN OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=7QEN 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]] 3.46&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=ATP:ADENOSINE-5-TRIPHOSPHATE'>ATP</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</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=7qen FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=7qen OCA], [https://pdbe.org/7qen PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=7qen RCSB], [https://www.ebi.ac.uk/pdbsum/7qen PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=7qen ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/SMC4_YEAST SMC4_YEAST] Central component of the condensin complex, a complex required for conversion of interphase chromatin into mitotic-like condense chromosomes. The condensin complex probably introduces positive supercoils into relaxed DNA in the presence of type I topoisomerases and converts nicked DNA into positive knotted forms in the presence of type II topoisomerases.
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Structural maintenance of chromosomes (SMC) protein complexes structure genomes by extruding DNA loops, but the molecular mechanism that underlies their activity has remained unknown. We show that the active condensin complex entraps the bases of a DNA loop transiently in two separate chambers. Single-molecule imaging and cryo-electron microscopy suggest a putative power-stroke movement at the first chamber that feeds DNA into the SMC-kleisin ring upon adenosine triphosphate binding, whereas the second chamber holds on upstream of the same DNA double helix. Unlocking the strict separation of "motor" and "anchor" chambers turns condensin from a one-sided into a bidirectional DNA loop extruder. We conclude that the orientation of two topologically bound DNA segments during the SMC reaction cycle determines the directionality of DNA loop extrusion.

A hold-and-feed mechanism drives directional DNA loop extrusion by condensin.,Shaltiel IA, Datta S, Lecomte L, Hassler M, Kschonsak M, Bravo S, Stober C, Ormanns J, Eustermann S, Haering CH Science. 2022 Jun 3;376(6597):1087-1094. doi: 10.1126/science.abm4012. Epub 2022 , Jun 2. PMID:35653469<ref>PMID:35653469</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 7qen" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Saccharomyces cerevisiae]]
[[Category: Saccharomyces cerevisiae CEN PK113-7D]]
[[Category: Synthetic construct]]
[[Category: Eustermann S]]
[[Category: Haering C]]
[[Category: Hassler M]]
[[Category: Lecomte L]]