View source for 7sbb


==Structure of type I-D Cascade bound to a ssRNA target==
<StructureSection load='7sbb' size='340' side='right'caption='[[7sbb]], [[Resolution|resolution]] 3.10&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[7sbb]] is a 13 chain structure with sequence from [https://en.wikipedia.org/wiki/Synechocystis_sp._PCC_6803 Synechocystis sp. PCC 6803] 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=7SBB OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=7SBB 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]] 3.1&#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=7sbb FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=7sbb OCA], [https://pdbe.org/7sbb PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=7sbb RCSB], [https://www.ebi.ac.uk/pdbsum/7sbb PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=7sbb ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/Q6ZEI7_SYNY3 Q6ZEI7_SYNY3] 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
CRISPR-Cas systems are adaptive immune systems that protect prokaryotes from foreign nucleic acids, such as bacteriophages. Two of the most prevalent CRISPR-Cas systems include type I and type III. Interestingly, the type I-D interference proteins contain characteristic features of both type I and type III systems. Here, we present the structures of type I-D Cascade bound to both a double-stranded (ds)DNA and a single-stranded (ss)RNA target at 2.9 and 3.1 A, respectively. We show that type I-D Cascade is capable of specifically binding ssRNA and reveal how PAM recognition of dsDNA targets initiates long-range structural rearrangements that likely primes Cas10d for Cas3' binding and subsequent non-target strand DNA cleavage. These structures allow us to model how binding of the anti-CRISPR protein AcrID1 likely blocks target dsDNA binding via competitive inhibition of the DNA substrate engagement with the Cas10d active site. This work elucidates the unique mechanisms used by type I-D Cascade for discrimination of single-stranded and double stranded targets. Thus, our data supports a model for the hybrid nature of this complex with features of type III and type I systems.

Structural rearrangements allow nucleic acid discrimination by type I-D Cascade.,Schwartz EA, McBride TM, Bravo JPK, Wrapp D, Fineran PC, Fagerlund RD, Taylor DW Nat Commun. 2022 May 20;13(1):2829. doi: 10.1038/s41467-022-30402-8. PMID:35595728<ref>PMID:35595728</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 7sbb" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Synechocystis sp. PCC 6803]]
[[Category: Synthetic construct]]
[[Category: Schwartz EA]]
[[Category: Taylor DW]]