View source for 4cmq


==Crystal structure of Mn-bound S.pyogenes Cas9==
<StructureSection load='4cmq' size='340' side='right'caption='[[4cmq]], [[Resolution|resolution]] 3.09&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[4cmq]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Streptococcus_pyogenes_serotype_M1 Streptococcus pyogenes serotype M1]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4CMQ OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4CMQ 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]] 3.09&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=MN:MANGANESE+(II)+ION'>MN</scene>, <scene name='pdbligand=SO4:SULFATE+ION'>SO4</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=4cmq FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4cmq OCA], [https://pdbe.org/4cmq PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4cmq RCSB], [https://www.ebi.ac.uk/pdbsum/4cmq PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4cmq ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/CAS9_STRP1 CAS9_STRP1] CRISPR (clustered regularly interspaced short palindromic repeat) is an adaptive immune system that provides protection against mobile genetic elements (viruses, transposable elements and conjugative plasmids). CRISPR clusters contain spacers, sequences complementary to antecedent mobile elements, and target invading nucleic acids. CRISPR clusters are transcribed and processed into CRISPR RNA (crRNA) (Probable). In type II CRISPR systems correct processing of pre-crRNA requires a trans-encoded small RNA (tracrRNA), endogenous ribonuclease 3 (rnc) and this protein. The tracrRNA serves as a guide for ribonuclease 3-aided processing of pre-crRNA. Subsequently Cas9/crRNA/tracrRNA endonucleolytically cleaves linear or circular dsDNA target complementary to the spacer. The target strand not complementary to crRNA is first cut endonucleolytically, then trimmed by 3'-5' exonucleolytically. DNA-binding requires protein and both RNA species. Cas9 probably recognizes a short motif in the CRISPR repeat sequences (the PAM or protospacer adjacent motif) to help distinguish self versus nonself.<ref>PMID:21455174</ref> <ref>PMID:22745249</ref> 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Type II CRISPR-Cas systems use an RNA-guided DNA endonuclease, Cas9, to generate double-strand breaks in invasive DNA during an adaptive bacterial immune response. Cas9 has been harnessed as a powerful tool for genome editing and gene regulation in many eukaryotic organisms. Here, we report 2.6 and 2.2 A resolution crystal structures of two major Cas9 enzymes subtypes, revealing the structural core shared by all Cas9 family members. The architectures of Cas9 enzymes define nucleic acid binding clefts, and single-particle electron microscopy reconstructions show that the two structural lobes harboring these clefts undergo guide RNA-induced reorientation to form a central channel where DNA substrates are bound. The observation that extensive structural rearrangements occur before target DNA duplex binding implicates guide RNA loading as a key step in Cas9 activation.

Structures of Cas9 Endonucleases Reveal RNA-Mediated Conformational Activation.,Jinek M, Jiang F, Taylor DW, Sternberg SH, Kaya E, Ma E, Anders C, Hauer M, Zhou K, Lin S, Kaplan M, Iavarone AT, Charpentier E, Nogales E, Doudna JA Science. 2014 Feb 6. PMID:24505130<ref>PMID:24505130</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 4cmq" style="background-color:#fffaf0;"></div>

==See Also==
*[[Endonuclease 3D structures|Endonuclease 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Streptococcus pyogenes serotype M1]]
[[Category: Anders C]]
[[Category: Charpentier E]]
[[Category: Doudna JA]]
[[Category: Hauer M]]
[[Category: Iavarone AT]]
[[Category: Jiang F]]
[[Category: Jinek M]]
[[Category: Kaplan M]]
[[Category: Kaya E]]
[[Category: Lin S]]
[[Category: Ma E]]
[[Category: Nogales E]]
[[Category: Sternberg SH]]
[[Category: Taylor DW]]
[[Category: Zhou K]]