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Open data
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Basic information
Entry | Database: PDB / ID: 8vah | ||||||
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Title | E.coli PNPase in complex with single 8-oxoG RNA | ||||||
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![]() | RNA BINDING PROTEIN / PNPase / oxidized RNA / Phosphorolysis / 8-oxo G | ||||||
Function / homology | ![]() polyribonucleotide nucleotidyltransferase / polyribonucleotide nucleotidyltransferase activity / mRNA catabolic process / RNA processing / 3'-5'-RNA exonuclease activity / magnesium ion binding / RNA binding / cytosol Similarity search - Function | ||||||
Biological species | ![]() ![]() | ||||||
Method | ELECTRON MICROSCOPY / single particle reconstruction / cryo EM / Resolution: 3.15 Å | ||||||
![]() | Kim, W. / Zhang, Y.J. | ||||||
Funding support | ![]()
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![]() | ![]() Title: Selective 8-oxo-rG stalling occurs in the catalytic core of polynucleotide phosphorylase (PNPase) during degradation. Authors: Lucas G Miller / Wantae Kim / Shawn Schowe / Kathleen Taylor / Runhua Han / Vashita Jain / Raeyeon Park / Mark Sherman / Janssen Fang / Haydee Ramirez / Andrew Ellington / Phanourios Tamamis ...Authors: Lucas G Miller / Wantae Kim / Shawn Schowe / Kathleen Taylor / Runhua Han / Vashita Jain / Raeyeon Park / Mark Sherman / Janssen Fang / Haydee Ramirez / Andrew Ellington / Phanourios Tamamis / Marino J E Resendiz / Y Jessie Zhang / Lydia Contreras / ![]() Abstract: RNA oxidation, predominantly through the accumulation of 8-oxo-7,8-dihydroguanosine (8-oxo-rG), represents an important biomarker for cellular oxidative stress. Polynucleotide phosphorylase (PNPase) ...RNA oxidation, predominantly through the accumulation of 8-oxo-7,8-dihydroguanosine (8-oxo-rG), represents an important biomarker for cellular oxidative stress. Polynucleotide phosphorylase (PNPase) is a 3'-5' exoribonuclease that has been shown to preferentially recognize 8-oxo-rG-containing RNA and protect cells from oxidative stress. However, the impact of 8-oxo-rG on PNPase-mediated RNA degradation has not been studied. Here, we show that the presence of 8-oxo-rG in RNA leads to catalytic stalling of PNPase through in vitro RNA degradation experiments and electrophoretic analysis. We also link this stalling to the active site of the enzyme through resolution of single-particle cryo-EM structures for PNPase in complex with singly or doubly oxidized RNA oligonucleotides. Following identification of Arg399 as a key residue in recognition of both single and sequential 8-oxo-rG nucleotides, we perform follow-up in vitro analysis to confirm the importance of this residue in 8-oxo-rG-specific PNPase stalling. Finally, we investigate the effects of mutations to active site residues implicated in 8-oxo-rG binding through cell growth experiments under HO-induced oxidative stress. Specifically, Arg399 mutations show significant effects on cell growth under oxidative stress. Overall, we demonstrate that 8-oxo-rG-specific stalling of PNPase is relevant to bacterial survival under oxidative stress and speculate that this enzyme might associate with other cellular factors to mediate this stress. | ||||||
History |
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Structure visualization
Structure viewer | Molecule: ![]() ![]() |
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Downloads & links
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Download
PDBx/mmCIF format | ![]() | 358 KB | Display | ![]() |
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PDB format | ![]() | 293.8 KB | Display | ![]() |
PDBx/mmJSON format | ![]() | Tree view | ![]() | |
Others | ![]() |
-Validation report
Arichive directory | ![]() ![]() | HTTPS FTP |
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-Related structure data
Related structure data | ![]() 43092MC ![]() 8vakC M: map data used to model this data C: citing same article ( |
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Similar structure data | Similarity search - Function & homology ![]() |
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Links
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Assembly
Deposited unit | ![]()
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Components
#1: Protein | Mass: 77189.844 Da / Num. of mol.: 3 Source method: isolated from a genetically manipulated source Source: (gene. exp.) ![]() ![]() ![]() ![]() #2: RNA chain | | Mass: 2917.895 Da / Num. of mol.: 1 / Source method: obtained synthetically / Source: (synth.) ![]() ![]() #3: RNA chain | Mass: 1279.841 Da / Num. of mol.: 3 / Source method: obtained synthetically / Source: (synth.) ![]() ![]() #4: Chemical | Has ligand of interest | Y | Has protein modification | N | |
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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 |
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Sample preparation
Component | Name: PNPase complexed with single 8-oxo G RNA / Type: COMPLEX / Entity ID: #1-#3 / Source: RECOMBINANT |
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Molecular weight | Experimental value: NO |
Source (natural) | Organism: ![]() ![]() |
Source (recombinant) | Organism: ![]() ![]() |
Buffer solution | pH: 7.4 |
Specimen | Conc.: 5 mg/ml / Embedding applied: NO / Shadowing applied: NO / Staining applied: NO / Vitrification applied: YES |
Vitrification | Instrument: FEI VITROBOT MARK IV / Cryogen name: ETHANE |
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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: ![]() |
Electron lens | Mode: BRIGHT FIELD / Nominal defocus max: 1900 nm / Nominal defocus min: 500 nm |
Image recording | Electron dose: 69 e/Å2 / Film or detector model: GATAN K3 (6k x 4k) |
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Processing
EM software | Name: PHENIX / Version: 1.18rc3_3805: / Category: model refinement | ||||||||||||||||||||||||
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CTF correction | Type: PHASE FLIPPING AND AMPLITUDE CORRECTION | ||||||||||||||||||||||||
Symmetry | Point symmetry: C1 (asymmetric) | ||||||||||||||||||||||||
3D reconstruction | Resolution: 3.15 Å / Resolution method: FSC 0.143 CUT-OFF / Num. of particles: 705788 / Symmetry type: POINT | ||||||||||||||||||||||||
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