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6ai6

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Revision as of 21:28, 28 October 2020

Crystal structure of SpCas9-NG

Structural highlights

6ai6 is a 4 chain structure. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Ligands:	, ,
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

[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.^[1] ^[2]

Publication Abstract from PubMed

The RNA-guided endonuclease Cas9 cleaves its target DNA and is a powerful genome-editing tool. However, the widely used Streptococcus pyogenes Cas9 enzyme (SpCas9) requires an NGG protospacer adjacent motif (PAM) for target recognition, thereby restricting the targetable genomic loci. Here, we report a rationally engineered SpCas9 variant (SpCas9-NG) that can recognize relaxed NG PAMs. The crystal structure revealed that the loss of the base-specific interaction with the third nucleobase is compensated by newly introduced non-base-specific interactions, thereby enabling the NG PAM recognition. We showed that SpCas9-NG induces indels at endogenous target sites bearing NG PAMs in human cells. Furthermore, we found that the fusion of SpCas9-NG and the activation-induced cytidine deaminase (AID) mediates the C-to-T conversion at target sites with NG PAMs in human cells.

Engineered CRISPR-Cas9 nuclease with expanded targeting space.,Nishimasu H, Shi X, Ishiguro S, Gao L, Hirano S, Okazaki S, Noda T, Abudayyeh OO, Gootenberg JS, Mori H, Oura S, Holmes B, Tanaka M, Seki M, Hirano H, Aburatani H, Ishitani R, Ikawa M, Yachie N, Zhang F, Nureki O Science. 2018 Sep 21;361(6408):1259-1262. doi: 10.1126/science.aas9129. Epub 2018, Aug 30. PMID:30166441^[3]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

References

↑ Deltcheva E, Chylinski K, Sharma CM, Gonzales K, Chao Y, Pirzada ZA, Eckert MR, Vogel J, Charpentier E. CRISPR RNA maturation by trans-encoded small RNA and host factor RNase III. Nature. 2011 Mar 31;471(7340):602-7. doi: 10.1038/nature09886. PMID:21455174 doi:http://dx.doi.org/10.1038/nature09886
↑ Jinek M, Chylinski K, Fonfara I, Hauer M, Doudna JA, Charpentier E. A programmable dual-RNA-guided DNA endonuclease in adaptive bacterial immunity. Science. 2012 Aug 17;337(6096):816-21. doi: 10.1126/science.1225829. Epub 2012, Jun 28. PMID:22745249 doi:http://dx.doi.org/10.1126/science.1225829
↑ Nishimasu H, Shi X, Ishiguro S, Gao L, Hirano S, Okazaki S, Noda T, Abudayyeh OO, Gootenberg JS, Mori H, Oura S, Holmes B, Tanaka M, Seki M, Hirano H, Aburatani H, Ishitani R, Ikawa M, Yachie N, Zhang F, Nureki O. Engineered CRISPR-Cas9 nuclease with expanded targeting space. Science. 2018 Sep 21;361(6408):1259-1262. doi: 10.1126/science.aas9129. Epub 2018, Aug 30. PMID:30166441 doi:http://dx.doi.org/10.1126/science.aas9129

1 Structural highlights
2 Function
3 Publication Abstract from PubMed
4 References

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/6ai6"

@@ Line 1: / Line 1: @@
 ==Crystal structure of SpCas9-NG==
-<StructureSection load='6ai6' size='340' side='right' caption='[[6ai6]], [[Resolution|resolution]] 2.70&Aring;' scene=''>
+<StructureSection load='6ai6' size='340' side='right'caption='[[6ai6]], [[Resolution|resolution]] 2.70&Aring;' scene=''>
 == Structural highlights ==
-<table><tr><td colspan='2'>[[6ai6]] is a 4 chain structure. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=6AI6 OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=6AI6 FirstGlance]. <br>
+<table><tr><td colspan='2'>[[6ai6]] is a 4 chain structure. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=6AI6 OCA]. For a <b>guided tour on the structure components</b> use [http://proteopedia.org/fgij/fg.htm?mol=6AI6 FirstGlance]. <br>
-</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=EDO:1,2-ETHANEDIOL'>EDO</scene>, <scene name='pdbligand=K:POTASSIUM+ION'>K</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene></td></tr>
+</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=EDO:1,2-ETHANEDIOL'>EDO</scene>, <scene name='pdbligand=K:POTASSIUM+ION'>K</scene>, <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'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=6ai6 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=6ai6 OCA], [http://pdbe.org/6ai6 PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=6ai6 RCSB], [http://www.ebi.ac.uk/pdbsum/6ai6 PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=6ai6 ProSAT]</span></td></tr>
+<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://proteopedia.org/fgij/fg.htm?mol=6ai6 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=6ai6 OCA], [http://pdbe.org/6ai6 PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=6ai6 RCSB], [http://www.ebi.ac.uk/pdbsum/6ai6 PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=6ai6 ProSAT]</span></td></tr>
 </table>
 == Function ==
@@ Line 22: / Line 22: @@
 __TOC__
 </StructureSection>
+[[Category: Large Structures]]
 [[Category: Hirano, S]]
 [[Category: Ishitani, R]]

6ai6

From Proteopedia

Revision as of 21:28, 28 October 2020

Crystal structure of SpCas9-NG

Structural highlights

Function

Publication Abstract from PubMed

References

Contents

Proteopedia Page Contributors and Editors (what is this?)

Views

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