View source for 6ifk


==Cryo-EM structure of type III-A Csm-CTR1 complex, AMPPNP bound==
<SX load='6ifk' size='340' side='right' viewer='molstar' caption='[[6ifk]], [[Resolution|resolution]] 3.20&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[6ifk]] is a 10 chain structure with sequence from [https://en.wikipedia.org/wiki/Streptococcus_thermophilus_ND03 Streptococcus thermophilus ND03]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=6IFK OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=6IFK 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]] 3.2&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=ANP:PHOSPHOAMINOPHOSPHONIC+ACID-ADENYLATE+ESTER'>ANP</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=6ifk FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=6ifk OCA], [https://pdbe.org/6ifk PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=6ifk RCSB], [https://www.ebi.ac.uk/pdbsum/6ifk PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=6ifk ProSAT]</span></td></tr>
</table>
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== Publication Abstract from PubMed ==
Csm, a type III-A CRISPR-Cas interference complex, is a CRISPR RNA (crRNA)-guided RNase that also possesses target RNA-dependent DNase and cyclic oligoadenylate (cOA) synthetase activities. However, the structural features allowing target RNA-binding-dependent activation of DNA cleavage and cOA generation remain unknown. Here, we report the structure of Csm in complex with crRNA together with structures of cognate or non-cognate target RNA bound Csm complexes. We show that depending on complementarity with the 5' tag of crRNA, the 3' anti-tag region of target RNA binds at two distinct sites of the Csm complex. Importantly, the interaction between the non-complementary anti-tag region of cognate target RNA and Csm1 induces a conformational change at the Csm1 subunit that allosterically activates DNA cleavage and cOA generation. Together, our structural studies provide crucial insights into the mechanistic processes required for crRNA-meditated sequence-specific RNA cleavage, RNA target-dependent non-specific DNA cleavage, and cOA generation.

Structure Studies of the CRISPR-Csm Complex Reveal Mechanism of Co-transcriptional Interference.,You L, Ma J, Wang J, Artamonova D, Wang M, Liu L, Xiang H, Severinov K, Zhang X, Wang Y Cell. 2018 Nov 26. pii: S0092-8674(18)31451-X. doi: 10.1016/j.cell.2018.10.052. PMID:30503210<ref>PMID:30503210</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 6ifk" style="background-color:#fffaf0;"></div>
== References ==
<references/>
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</SX>
[[Category: Large Structures]]
[[Category: Streptococcus thermophilus ND03]]
[[Category: Ma J]]
[[Category: Wang J]]
[[Category: Wang Y]]
[[Category: You L]]
[[Category: Zhang X]]