View source for 8y04


==Crystal structure of LbCas12a in complex with crRNA and 6nt target DNA==
<StructureSection load='8y04' size='340' side='right'caption='[[8y04]], [[Resolution|resolution]] 3.71&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[8y04]] is a 4 chain structure with sequence from [https://en.wikipedia.org/wiki/Lachnospiraceae_bacterium_ND2006 Lachnospiraceae bacterium ND2006]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=8Y04 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=8Y04 FirstGlance]. <br>
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 3.71&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><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=8y04 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=8y04 OCA], [https://pdbe.org/8y04 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=8y04 RCSB], [https://www.ebi.ac.uk/pdbsum/8y04 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=8y04 ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/A0A5S8WF58_9FIRM A0A5S8WF58_9FIRM] 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Precursor (pre)-CRISPR RNA (crRNA) processing can occur in both the repeat and spacer regions, leading to the removal of specific segments from the repeat and spacer sequences, thereby facilitating crRNA maturation. The processing of pre-crRNA repeat by Cas effector and ribonuclease has been observed in CRISPR-Cas9 and CRISPR-Cas12a systems. However, no evidence of pre-crRNA spacer cleavage by any enzyme has been reported in these systems. In this study, we demonstrate that DNA target binding triggers efficient cleavage of pre-crRNA spacers by type II and V Cas effectors such as Cas12a, Cas12b, Cas12i, Cas12j and Cas9. We show that the pre-crRNA spacer cleavage catalyzed by Cas12a and Cas9 has distinct characteristics. Activation of the cleavage activity in Cas12a is induced by both single-stranded DNA (ssDNA) and double-stranded DNA target binding, whereas only ssDNA target binding triggers cleavage in Cas9 toward the pre-crRNA spacer. We present a series of structures elucidating the underlying mechanisms governing conformational activation in both Cas12a and Cas9. Furthermore, leveraging the trans-cutting activity of the pre-crRNA spacer, we develop a one-step DNA detection method characterized by its simplicity, high sensitivity, and excellent specificity.

DNA target binding-induced pre-crRNA processing in type II and V CRISPR-Cas systems.,Chen J, Lin X, Xiang W, Chen Y, Zhao Y, Huang L, Liu L Nucleic Acids Res. 2024 Dec 16:gkae1241. doi: 10.1093/nar/gkae1241. PMID:39676682<ref>PMID:39676682</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 8y04" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Lachnospiraceae bacterium ND2006]]
[[Category: Large Structures]]
[[Category: Chen J]]
[[Category: Lin X]]
[[Category: Liu L]]