+Open data
-Basic information
Entry | Database: EMDB / ID: EMD-21551 | |||||||||
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Title | Cryo-EM structure of Cas12i-crRNA complex | |||||||||
Map data | sharpened | |||||||||
Sample |
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Keywords | CRISPR / HYDROLASE-DNA-RNA complex | |||||||||
Biological species | Lachnospiraceae bacterium ND2006 (bacteria) | |||||||||
Method | single particle reconstruction / cryo EM / Resolution: 3.9 Å | |||||||||
Authors | Chang L / Li Z / Zhang H | |||||||||
Citation | Journal: Nat Struct Mol Biol / Year: 2020 Title: Mechanisms for target recognition and cleavage by the Cas12i RNA-guided endonuclease. Authors: Heng Zhang / Zhuang Li / Renjian Xiao / Leifu Chang / Abstract: Cas12i is a recently identified type V CRISPR-Cas endonuclease that predominantly cleaves the non-target strand of a double-stranded DNA substrate. This nicking activity of Cas12i could potentially ...Cas12i is a recently identified type V CRISPR-Cas endonuclease that predominantly cleaves the non-target strand of a double-stranded DNA substrate. This nicking activity of Cas12i could potentially be used for genome editing with high specificity. To elucidate its mechanisms for target recognition and cleavage, we determined cryo-EM structures of Cas12i in multiple functional states. Cas12i pre-orders a seven-nucleotide seed sequence of the crRNA for target recognition and undergoes a two-step activation through crRNA-DNA hybridization. Formation of 14 base pairs activates the nickase activity, and 28-bp hybridization promotes cleavage of the target strand. The atomic structures and mechanistic insights gained should facilitate the manipulation of Cas12i for genome editing applications. | |||||||||
History |
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-Structure visualization
Movie |
Movie viewer |
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Structure viewer | EM map: SurfViewMolmilJmol/JSmol |
Supplemental images |
-Downloads & links
-EMDB archive
Map data | emd_21551.map.gz | 2.4 MB | EMDB map data format | |
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Header (meta data) | emd-21551-v30.xml emd-21551.xml | 11.4 KB 11.4 KB | Display Display | EMDB header |
Images | emd_21551.png | 116.9 KB | ||
Filedesc metadata | emd-21551.cif.gz | 5.8 KB | ||
Archive directory | http://ftp.pdbj.org/pub/emdb/structures/EMD-21551 ftp://ftp.pdbj.org/pub/emdb/structures/EMD-21551 | HTTPS FTP |
-Validation report
Summary document | emd_21551_validation.pdf.gz | 359.8 KB | Display | EMDB validaton report |
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Full document | emd_21551_full_validation.pdf.gz | 359.3 KB | Display | |
Data in XML | emd_21551_validation.xml.gz | 5.5 KB | Display | |
Data in CIF | emd_21551_validation.cif.gz | 6.2 KB | Display | |
Arichive directory | https://ftp.pdbj.org/pub/emdb/validation_reports/EMD-21551 ftp://ftp.pdbj.org/pub/emdb/validation_reports/EMD-21551 | HTTPS FTP |
-Related structure data
Related structure data | 6w62MC 6w5cC 6w64C C: citing same article (ref.) M: atomic model generated by this map |
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Similar structure data |
-Links
EMDB pages | EMDB (EBI/PDBe) / EMDataResource |
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-Map
File | Download / File: emd_21551.map.gz / Format: CCP4 / Size: 27 MB / Type: IMAGE STORED AS FLOATING POINT NUMBER (4 BYTES) | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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Annotation | sharpened | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Voxel size | X=Y=Z: 1.05 Å | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Density |
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Symmetry | Space group: 1 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Details | EMDB XML:
CCP4 map header:
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-Supplemental data
-Sample components
-Entire : Cryo-EM structure of CRISPR-Cas complex
Entire | Name: Cryo-EM structure of CRISPR-Cas complex |
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Components |
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-Supramolecule #1: Cryo-EM structure of CRISPR-Cas complex
Supramolecule | Name: Cryo-EM structure of CRISPR-Cas complex / type: complex / ID: 1 / Parent: 0 / Macromolecule list: all |
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Source (natural) | Organism: Lachnospiraceae bacterium ND2006 (bacteria) |
-Macromolecule #1: Cas12i
Macromolecule | Name: Cas12i / type: protein_or_peptide / ID: 1 / Number of copies: 1 / Enantiomer: LEVO |
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Source (natural) | Organism: Lachnospiraceae bacterium ND2006 (bacteria) |
Molecular weight | Theoretical: 125.879211 KDa |
Recombinant expression | Organism: Escherichia coli BL21(DE3) (bacteria) |
Sequence | String: MSNKEKNASE TRKAYTTKMI PRSHDRMKLL GNFMDYLMDG TPIFFELWNQ FGGGIDRDII SGTANKDKIS DDLLLAVNWF KVMPINSKP QGVSPSNLAN LFQQYSGSEP DIQAQEYFAS NFDTEKHQWK DMRVEYERLL AELQLSRSDM HHDLKLMYKE K CIGLSLST ...String: MSNKEKNASE TRKAYTTKMI PRSHDRMKLL GNFMDYLMDG TPIFFELWNQ FGGGIDRDII SGTANKDKIS DDLLLAVNWF KVMPINSKP QGVSPSNLAN LFQQYSGSEP DIQAQEYFAS NFDTEKHQWK DMRVEYERLL AELQLSRSDM HHDLKLMYKE K CIGLSLST AHYITSVMFG TGAKNNRQTK HQFYSKVIQL LEESTQINSV EQLASIILKA GDCDSYRKLR IRCSRKGATP SI LKIVQDY ELGTNHDDEV NVPSLIANLK EKLGRFEYEC EWKCMEKIKA FLASKVGPYY LGSYSAMLEN ALSPIKGMTT KNC KFVLKQ IDAKNDIKYE NEPFGKIVEG FFDSPYFESD TNVKWVLHPH HIGESNIKTL WEDLNAIHSK YEEDIASLSE DKKE KRIKV YQGDVCQTIN TYCEEVGKEA KTPLVQLLRY LYSRKDDIAV DKIIDGITFL SKKHKVEKQK INPVIQKYPS FNFGN NSKL LGKIISPKDK LKHNLKCNRN QVDNYIWIEI KVLNTKTMRW EKHHYALSST RFLEEVYYPA TSENPPDALA ARFRTK TNG YEGKPALSAE QIEQIRSAPV GLRKVKKRQM RLEAARQQNL LPRYTWGKDF NINICKRGNN FEVTLATKVK KKKEKNY KV VLGYDANIVR KNTYAAIEAH ANGDGVIDYN DLPVKPIESG FVTVESQVRD KSYDQLSYNG VKLLYCKPHV ESRRSFLE K YRNGTMKDNR GNNIQIDFMK DFEAIADDET SLYYFNMKYC KLLQSSIRNH SSQAKEYREE IFELLRDGKL SVLKLSSLS NLSFVMFKVA KSLIGTYFGH LLKKPKNSKS DVKAPPITDE DKQKADPEMF ALRLALEEKR LNKVKSKKEV IANKIVAKAL ELRDKYGPV LIKGENISDT TKKGKKSSTN SFLMDWLARG VANKVKEMVM MHQGLEFVEV NPNFTSHQDP FVHKNPENTF R ARYSRCTP SELTEKNRKE ILSFLSDKPS KRPTNAYYNE GAMAFLATYG LKKNDVLGVS LEKFKQIMAN ILHQRSEDQL LF PSRGGMF YLATYKLDAD ATSVNWNGKQ FWVCNADLVA AYNVGLVDIQ KDFKKK |
-Macromolecule #2: crRNA
Macromolecule | Name: crRNA / type: rna / ID: 2 / Number of copies: 1 |
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Source (natural) | Organism: Lachnospiraceae bacterium ND2006 (bacteria) |
Molecular weight | Theoretical: 9.581721 KDa |
Sequence | String: CAAAUUGUGC CCAUCGUUGG CACGCGUGCA |
-Experimental details
-Structure determination
Method | cryo EM |
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Processing | single particle reconstruction |
Aggregation state | particle |
-Sample preparation
Concentration | .5 mg/mL |
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Buffer | pH: 7.5 |
Grid | Details: unspecified |
Vitrification | Cryogen name: ETHANE |
-Electron microscopy
Microscope | FEI TITAN KRIOS |
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Image recording | #0 - Image recording ID: 1 / #0 - Film or detector model: GATAN K3 (6k x 4k) / #0 - Detector mode: SUPER-RESOLUTION / #0 - Average electron dose: 35.0 e/Å2 / #1 - Image recording ID: 2 / #1 - Film or detector model: GATAN K2 SUMMIT (4k x 4k) / #1 - Average electron dose: 1.3 e/Å2 |
Electron beam | Acceleration voltage: 300 kV / Electron source: FIELD EMISSION GUN |
Electron optics | Illumination mode: SPOT SCAN / Imaging mode: BRIGHT FIELD |
Experimental equipment | Model: Titan Krios / Image courtesy: FEI Company |