View source for 9ioa


==Cryo-EM structure of the tetrameric DRT9-ncRNA complex==
<StructureSection load='9ioa' size='340' side='right'caption='[[9ioa]], [[Resolution|resolution]] 2.59&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[9ioa]] is a 8 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=9IOA OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=9IOA 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]] 2.59&#8491;</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=9ioa FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=9ioa OCA], [https://pdbe.org/9ioa PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=9ioa RCSB], [https://www.ebi.ac.uk/pdbsum/9ioa PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=9ioa ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/A0A6D0I497_ECOLX A0A6D0I497_ECOLX] 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Prokaryotic defense-associated reverse transcriptases (DRTs) were recently identified with antiviral functions; however, their functional mechanisms remain largely unexplored. Here we show that DRT9 forms a hexameric complex with its upstream non-coding RNA (ncRNA) to mediate antiphage defense by inducing cell growth arrest via abortive infection. Upon phage infection, the phage-encoded ribonucleotide reductase NrdAB complex elevates intracellular dATP levels, activating DRT9 to synthesize long, poly-A-rich single-stranded cDNA, which likely sequesters the essential phage SSB protein and disrupts phage propagation. We further determined the cryo-electron microscopy structure of the DRT9-ncRNA hexamer complex, providing mechanistic insights into its cDNA synthesis. These findings highlight the diversity of RT-based antiviral defense mechanisms, expand our understanding of RT biological functions, and provide a structural basis for developing DRT9-based biotechnological tools.

Bacterial reverse transcriptase synthesizes long poly-A-rich cDNA for antiphage defense.,Song XY, Xia Y, Zhang JT, Liu YJ, Qi H, Wei XY, Hu H, Xia Y, Liu X, Ma YF, Jia N Science. 2025 May 1:eads4639. doi: 10.1126/science.ads4639. PMID:40310939<ref>PMID:40310939</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 9ioa" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Escherichia coli]]
[[Category: Large Structures]]
[[Category: Jia N]]
[[Category: Song XY]]
[[Category: Wei XY]]
[[Category: Zhang JT]]