View source for 8glx


==CryoEM structure of the TnsC(1-503)-TnsD(1-318)-DNA complex in a 6:2:1 stoichiometry from E. coli Tn7==
<StructureSection load='8glx' size='340' side='right'caption='[[8glx]], [[Resolution|resolution]] 3.88&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[8glx]] is a 10 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=8GLX OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=8GLX 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]] 3.88&#8491;</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=ATP:ADENOSINE-5-TRIPHOSPHATE'>ATP</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene>, <scene name='pdbligand=ZN:ZINC+ION'>ZN</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=8glx FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=8glx OCA], [https://pdbe.org/8glx PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=8glx RCSB], [https://www.ebi.ac.uk/pdbsum/8glx PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=8glx ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/TNSC_ECOLX TNSC_ECOLX] TnsC binds non-specifically to DNA in the presence of ATP. It is required for Tn7 transposition.  TnsABC + TnsD promote high-frequency insertion of Tn7 into a specific target site known as att-Tn7 whereas TnsABC + TnsE promote low-frequency insertion into many different sites.
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
The Tn7 family of transposons is notable for its highly regulated integration mechanisms, including programmable RNA-guided transposition. The targeting pathways rely on dedicated target selection proteins from the TniQ family and the AAA+ adaptor TnsC to recruit and activate the transposase at specific target sites. Here, we report the cryoelectron microscopy (cryo-EM) structures of TnsC bound to the TniQ domain of TnsD from prototypical Tn7 and unveil key regulatory steps stemming from unique behaviors of ATP- versus ADP-bound TnsC. We show that TnsD recruits ADP-bound dimers of TnsC and acts as an exchange factor to release one protomer with exchange to ATP. This loading process explains how TnsC assembles a heptameric ring unidirectionally from the target site. This unique loading process results in functionally distinct TnsC protomers within the ring, providing a checkpoint for target immunity and explaining how insertions at programmed sites precisely occur in a specific orientation across Tn7 elements.

Assembly of the Tn7 targeting complex by a regulated stepwise process.,Shen Y, Krishnan SS, Petassi MT, Hancock MA, Peters JE, Guarne A Mol Cell. 2024 Jun 20;84(12):2368-2381.e6. doi: 10.1016/j.molcel.2024.05.012. , Epub 2024 Jun 3. PMID:38834067<ref>PMID:38834067</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 8glx" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Escherichia coli]]
[[Category: Large Structures]]
[[Category: Guarne A]]
[[Category: Shen Y]]