+Open data
-Basic information
Entry | Database: PDB / ID: 6nm9 | ||||||
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Title | CryoEM structure of the LbCas12a-crRNA-AcrVA4 dimer | ||||||
Components |
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Keywords | UNKNOWN FUNCTION/RNA / UNKNOWN FUNCTION-RNA complex | ||||||
Function / homology | Function and homology information | ||||||
Biological species | Moraxella bovoculi (bacteria) Lachnospiraceae bacterium ND2006 (bacteria) | ||||||
Method | ELECTRON MICROSCOPY / single particle reconstruction / cryo EM / Resolution: 3.38 Å | ||||||
Authors | Chang, L. / Li, Z. / Zhang, H. | ||||||
Citation | Journal: Cell Host Microbe / Year: 2019 Title: Structural Basis for the Inhibition of CRISPR-Cas12a by Anti-CRISPR Proteins. Authors: Heng Zhang / Zhuang Li / Courtney M Daczkowski / Clinton Gabel / Andrew D Mesecar / Leifu Chang / Abstract: CRISPR-Cas12a (Cpf1), a type V CRISPR-associated nuclease, provides bacterial immunity against bacteriophages and plasmids but also serves as a tool for genome editing. Foreign nucleic acids are ...CRISPR-Cas12a (Cpf1), a type V CRISPR-associated nuclease, provides bacterial immunity against bacteriophages and plasmids but also serves as a tool for genome editing. Foreign nucleic acids are integrated into the CRISPR locus, prompting transcription of CRISPR RNAs (crRNAs) that guide Cas12a cleavage of foreign complementary DNA. However, mobile genetic elements counteract Cas12a with inhibitors, notably type V-A anti-CRISPRs (AcrVAs). We present cryoelectron microscopy structures of Cas12a-crRNA bound to AcrVA1 and AcrVA4 at 3.5 and 3.3 Å resolutions, respectively. AcrVA1 is sandwiched between the recognition (REC) and nuclease (NUC) lobes of Cas12a and inserts into the binding pocket for the protospacer-adjacent motif (PAM), a short DNA sequence guiding Cas12a targeting. AcrVA1 cleaves crRNA in a Cas12a-dependent manner, inactivating Cas12a-crRNA complexes. The AcrVA4 dimer is anchored around the crRNA pseudoknot of Cas12a-crRNA, preventing required conformational changes for crRNA-DNA heteroduplex formation. These results uncover molecular mechanisms for CRISPR-Cas12a inhibition, providing insights into bacteria-phage dynamics. | ||||||
History |
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-Structure visualization
Movie |
Movie viewer |
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Structure viewer | Molecule: MolmilJmol/JSmol |
-Downloads & links
-Download
PDBx/mmCIF format | 6nm9.cif.gz | 513.3 KB | Display | PDBx/mmCIF format |
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PDB format | pdb6nm9.ent.gz | 410.5 KB | Display | PDB format |
PDBx/mmJSON format | 6nm9.json.gz | Tree view | PDBx/mmJSON format | |
Others | Other downloads |
-Validation report
Summary document | 6nm9_validation.pdf.gz | 811.7 KB | Display | wwPDB validaton report |
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Full document | 6nm9_full_validation.pdf.gz | 880.3 KB | Display | |
Data in XML | 6nm9_validation.xml.gz | 79.6 KB | Display | |
Data in CIF | 6nm9_validation.cif.gz | 118.9 KB | Display | |
Arichive directory | https://data.pdbj.org/pub/pdb/validation_reports/nm/6nm9 ftp://data.pdbj.org/pub/pdb/validation_reports/nm/6nm9 | HTTPS FTP |
-Related structure data
Related structure data | 9398MC 0445C 0446C 0447C 0449C 6nmaC 6nmcC 6nmdC 6nmeC 6omvC M: map data used to model this data C: citing same article (ref.) |
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Similar structure data |
-Links
-Assembly
Deposited unit |
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1 |
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-Components
#1: Protein | Mass: 27369.162 Da / Num. of mol.: 2 Source method: isolated from a genetically manipulated source Source: (gene. exp.) Moraxella bovoculi (bacteria) / Gene: AAX07_09545 / Production host: Escherichia coli (E. coli) / References: UniProt: A0A0U2APF4 #2: Protein | Mass: 143750.219 Da / Num. of mol.: 2 Source method: isolated from a genetically manipulated source Source: (gene. exp.) Lachnospiraceae bacterium ND2006 (bacteria) Production host: Escherichia coli (E. coli) / References: UniProt: A0A182DWE3 #3: RNA chain | Mass: 12879.634 Da / Num. of mol.: 2 / Source method: obtained synthetically Source: (synth.) Lachnospiraceae bacterium ND2006 (bacteria) #4: Chemical | ChemComp-MG / |
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-Experimental details
-Experiment
Experiment | Method: ELECTRON MICROSCOPY |
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EM experiment | Aggregation state: PARTICLE / 3D reconstruction method: single particle reconstruction |
-Sample preparation
Component | Name: protein complex 5 / Type: COMPLEX / Entity ID: #1-#3 / Source: MULTIPLE SOURCES |
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Source (natural) | Organism: Lachnospiraceae bacterium ND2006 (bacteria) |
Buffer solution | pH: 7.5 |
Specimen | Conc.: 1 mg/ml / Embedding applied: NO / Shadowing applied: NO / Staining applied: NO / Vitrification applied: YES |
Specimen support | Details: unspecified |
Vitrification | Cryogen name: ETHANE |
-Electron microscopy imaging
Experimental equipment | Model: Titan Krios / Image courtesy: FEI Company |
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Microscopy | Model: FEI TITAN KRIOS |
Electron gun | Electron source: FIELD EMISSION GUN / Accelerating voltage: 300 kV / Illumination mode: SPOT SCAN |
Electron lens | Mode: BRIGHT FIELD |
Image recording | Electron dose: 35 e/Å2 / Detector mode: SUPER-RESOLUTION / Film or detector model: GATAN K2 SUMMIT (4k x 4k) |
-Processing
Software | Name: PHENIX / Version: 1.15.2_3472: / Classification: refinement | ||||||||||||||||||||||||
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EM software | Name: cisTEM / Version: 1.0.0 / Category: 3D reconstruction | ||||||||||||||||||||||||
CTF correction | Type: PHASE FLIPPING ONLY | ||||||||||||||||||||||||
Symmetry | Point symmetry: C2 (2 fold cyclic) | ||||||||||||||||||||||||
3D reconstruction | Resolution: 3.38 Å / Resolution method: FSC 0.143 CUT-OFF / Num. of particles: 47609 / Symmetry type: POINT | ||||||||||||||||||||||||
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