+Open data
-Basic information
Entry | Database: EMDB / ID: EMD-5892 | |||||||||
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Title | CryoEM of C3PO assembled on ssRNA-ChemiC grids | |||||||||
Map data | C3PO on let7 ssRNA ChemiC grids | |||||||||
Sample |
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Keywords | Nuclease activity / RNA interference / ChemiC / C3PO / side port | |||||||||
Function / homology | Function and homology information : / endoribonuclease complex / Small interfering RNA (siRNA) biogenesis / regulatory ncRNA-mediated post-transcriptional gene silencing / siRNA processing / male germ cell nucleus / single-stranded DNA binding / endonuclease activity / DNA recombination / sequence-specific DNA binding ...: / endoribonuclease complex / Small interfering RNA (siRNA) biogenesis / regulatory ncRNA-mediated post-transcriptional gene silencing / siRNA processing / male germ cell nucleus / single-stranded DNA binding / endonuclease activity / DNA recombination / sequence-specific DNA binding / Hydrolases; Acting on ester bonds / mRNA binding / endoplasmic reticulum / DNA binding / RNA binding / nucleoplasm / identical protein binding / nucleus / cytosol / cytoplasm Similarity search - Function | |||||||||
Biological species | Homo sapiens (human) / unidentified (others) | |||||||||
Method | single particle reconstruction / cryo EM / Resolution: 15.0 Å | |||||||||
Authors | Llaguno MC / Xu H / Shi L / Huang H / Zhang H / Liu Q / Jiang Q | |||||||||
Citation | Journal: J Struct Biol / Year: 2014 Title: Chemically functionalized carbon films for single molecule imaging. Authors: Marc C Llaguno / Hui Xu / Liang Shi / Nian Huang / Hong Zhang / Qinghua Liu / Qiu-Xing Jiang / Abstract: Many biological complexes are naturally low in abundance and pose a significant challenge to their structural and functional studies. Here we describe a new method that utilizes strong oxidation and ...Many biological complexes are naturally low in abundance and pose a significant challenge to their structural and functional studies. Here we describe a new method that utilizes strong oxidation and chemical linkage to introduce a high density of bioactive ligands onto nanometer-thick carbon films and enable selective enrichment of individual macromolecular complexes at subnanogram levels. The introduced ligands are physically separated. Ni-NTA, Protein G and DNA/RNA oligonucleotides were covalently linked to the carbon surface. They embody negligible mass and their stability makes the functionalized films able to survive long-term storage and tolerate variations in pH, temperature, salts, detergents, and solvents. We demonstrated the application of the new method to the electron microscopic imaging of the substrate-bound C3PO, an RNA-processing enzyme important for the RNA interference pathway. On the ssRNA-linked carbon surface, the formation of C3PO oligomers at subnanomolar concentrations likely mimics their assembly onto ssRNA substrates presented by their native partners. Interestingly, the 3D reconstructions by negative stain EM reveal a side port in the C3PO/ssRNA complex, and the 15Å cryoEM map showed extra density right above the side port, which probably represents the ssRNA. These results suggest a new way for ssRNAs to interact with the active sites of the complex. Together our data demonstrate that the surface-engineered carbon films are suitable for selectively enriching low-abundance biological complexes at nanomolar level and for developing novel applications on a large number of surface-presented molecules. | |||||||||
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_5892.map.gz | 325.3 KB | EMDB map data format | |
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Header (meta data) | emd-5892-v30.xml emd-5892.xml | 12.3 KB 12.3 KB | Display Display | EMDB header |
Images | 400_5892.gif 80_5892.gif | 35.6 KB 3.5 KB | ||
Archive directory | http://ftp.pdbj.org/pub/emdb/structures/EMD-5892 ftp://ftp.pdbj.org/pub/emdb/structures/EMD-5892 | HTTPS FTP |
-Validation report
Summary document | emd_5892_validation.pdf.gz | 79.1 KB | Display | EMDB validaton report |
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Full document | emd_5892_full_validation.pdf.gz | 78.2 KB | Display | |
Data in XML | emd_5892_validation.xml.gz | 494 B | Display | |
Arichive directory | https://ftp.pdbj.org/pub/emdb/validation_reports/EMD-5892 ftp://ftp.pdbj.org/pub/emdb/validation_reports/EMD-5892 | HTTPS FTP |
-Related structure data
Similar structure data |
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-Links
EMDB pages | EMDB (EBI/PDBe) / EMDataResource |
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Related items in Molecule of the Month |
-Map
File | Download / File: emd_5892.map.gz / Format: CCP4 / Size: 3.3 MB / Type: IMAGE STORED AS FLOATING POINT NUMBER (4 BYTES) | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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Annotation | C3PO on let7 ssRNA ChemiC grids | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Projections & slices | Image control
Images are generated by Spider. | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Voxel size | X=Y=Z: 2.33 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 : Complex 3 Promoter of RISC (C3PO) assembled on the let7 ssRNA pre...
Entire | Name: Complex 3 Promoter of RISC (C3PO) assembled on the let7 ssRNA presented by ChemiC grids |
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Components |
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-Supramolecule #1000: Complex 3 Promoter of RISC (C3PO) assembled on the let7 ssRNA pre...
Supramolecule | Name: Complex 3 Promoter of RISC (C3PO) assembled on the let7 ssRNA presented by ChemiC grids type: sample / ID: 1000 / Details: The sample was monodisperse. / Oligomeric state: One C3PO octamer binds to one let7 ssRNA / Number unique components: 2 |
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Molecular weight | Experimental: 240 KDa / Theoretical: 240 KDa / Method: Gel filtration and ultra-centrifugation |
-Macromolecule #1: Component 3 Promoter of RISC
Macromolecule | Name: Component 3 Promoter of RISC / type: protein_or_peptide / ID: 1 / Name.synonym: C3PO Details: C3PO was incubated on let7 ssRNA presented on ChemiC films. Number of copies: 1 / Oligomeric state: Octamer / Recombinant expression: Yes |
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Source (natural) | Organism: Homo sapiens (human) / synonym: Human / Location in cell: cytoplasm |
Molecular weight | Experimental: 240 KDa / Theoretical: 240 KDa |
Recombinant expression | Organism: Escherichia coli (E. coli) / Recombinant strain: BL21(DE3) / Recombinant plasmid: pET Duet |
Sequence | UniProtKB: Translin / GO: GO: 0090305, RNA binding, nucleus / InterPro: Translin family |
-Macromolecule #2: let7 ssRNA
Macromolecule | Name: let7 ssRNA / type: rna / ID: 2 / Classification: OTHER / Structure: SINGLE STRANDED / Synthetic?: Yes |
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Source (natural) | Organism: unidentified (others) |
-Experimental details
-Structure determination
Method | cryo EM |
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Processing | single particle reconstruction |
Aggregation state | particle |
-Sample preparation
Concentration | 0.01 mg/mL |
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Buffer | pH: 8 / Details: 150 mM NaCl, 10 mM Tris-HCl |
Grid | Details: 400 mesh copper grid with thin carbon with covalently bound let7 ssRNA |
Vitrification | Cryogen name: ETHANE / Chamber humidity: 100 % / Chamber temperature: 77 K / Instrument: FEI VITROBOT MARK III / Method: blot for 7 seconds before plunging |
-Electron microscopy
Microscope | JEOL 2200FS |
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Temperature | Min: 77 K / Max: 110 K / Average: 100 K |
Alignment procedure | Legacy - Astigmatism: Astigmatism was corrected at 100,000 times magnification. |
Specialist optics | Energy filter - Name: JEOL Omega type / Energy filter - Lower energy threshold: 0.0 eV / Energy filter - Upper energy threshold: 25.0 eV |
Details | weak exposure, 12 min developing, 5 min quick fixing |
Date | Sep 4, 2012 |
Image recording | Category: FILM / Film or detector model: KODAK SO-163 FILM / Digitization - Scanner: ZEISS SCAI / Digitization - Sampling interval: 14 µm / Number real images: 294 / Average electron dose: 20 e/Å2 / Details: film images selected in a diffractometer / Od range: 1.2 / Bits/pixel: 8 |
Electron beam | Acceleration voltage: 200 kV / Electron source: FIELD EMISSION GUN |
Electron optics | Calibrated magnification: 61198 / Illumination mode: FLOOD BEAM / Imaging mode: BRIGHT FIELD / Cs: 2.0 mm / Nominal defocus max: 2.0 µm / Nominal defocus min: 1.0 µm / Nominal magnification: 60000 |
Sample stage | Specimen holder: Liquid nitrogen cooled / Specimen holder model: GATAN LIQUID NITROGEN |
-Image processing
Details | The particles were selected manually using the EMAN boxer program. |
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CTF correction | Details: each particle |
Final reconstruction | Algorithm: OTHER / Resolution.type: BY AUTHOR / Resolution: 15.0 Å / Resolution method: OTHER / Software - Name: IMAGIC, SPIDER, EMAN / Number images used: 38968 |
Final two d classification | Number classes: 1081 |