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Entry
Database: PDB / ID: 7cxm
TitleArchitecture of a SARS-CoV-2 mini replication and transcription complex
Components
  • (Non-structural protein ...) x 2
  • Helicase
  • RNA (25-MER)
  • RNA (26-MER)
  • RNA (5'-R(P*UP*UP*UP*UP*UP*U)-3')
  • RNA-directed RNA polymerase
KeywordsVIRAL PROTEIN/RNA / SARS-CoV-2 / RTC complex / VIRAL PROTEIN-RNA complex
Function / homology
Function and homology information


protein guanylyltransferase activity / RNA endonuclease activity producing 3'-phosphomonoesters, hydrolytic mechanism / mRNA guanylyltransferase activity / 5'-3' RNA helicase activity / Lyases; Phosphorus-oxygen lyases / Assembly of the SARS-CoV-2 Replication-Transcription Complex (RTC) / Maturation of replicase proteins / symbiont-mediated suppression of host cytoplasmic pattern recognition receptor signaling pathway via inhibition of TBK1 activity / ISG15-specific peptidase activity / TRAF3-dependent IRF activation pathway ...protein guanylyltransferase activity / RNA endonuclease activity producing 3'-phosphomonoesters, hydrolytic mechanism / mRNA guanylyltransferase activity / 5'-3' RNA helicase activity / Lyases; Phosphorus-oxygen lyases / Assembly of the SARS-CoV-2 Replication-Transcription Complex (RTC) / Maturation of replicase proteins / symbiont-mediated suppression of host cytoplasmic pattern recognition receptor signaling pathway via inhibition of TBK1 activity / ISG15-specific peptidase activity / TRAF3-dependent IRF activation pathway / Transcription of SARS-CoV-2 sgRNAs / Translation of Replicase and Assembly of the Replication Transcription Complex / snRNP Assembly / Replication of the SARS-CoV-2 genome / double membrane vesicle viral factory outer membrane / Hydrolases; Acting on ester bonds; Exoribonucleases producing 5'-phosphomonoesters / host cell endoplasmic reticulum-Golgi intermediate compartment / SARS coronavirus main proteinase / 3'-5'-RNA exonuclease activity / 5'-3' DNA helicase activity / host cell endosome / symbiont-mediated degradation of host mRNA / mRNA guanylyltransferase / symbiont-mediated suppression of host ISG15-protein conjugation / G-quadruplex RNA binding / symbiont-mediated suppression of host toll-like receptor signaling pathway / symbiont-mediated suppression of host cytoplasmic pattern recognition receptor signaling pathway via inhibition of IRF3 activity / omega peptidase activity / SARS-CoV-2 modulates host translation machinery / mRNA (guanine-N7)-methyltransferase / host cell Golgi apparatus / methyltransferase cap1 / symbiont-mediated perturbation of host ubiquitin-like protein modification / symbiont-mediated suppression of host NF-kappaB cascade / DNA helicase / methyltransferase cap1 activity / ubiquitinyl hydrolase 1 / cysteine-type deubiquitinase activity / mRNA 5'-cap (guanine-N7-)-methyltransferase activity / forked DNA-dependent helicase activity / single-stranded 3'-5' DNA helicase activity / four-way junction helicase activity / double-stranded DNA helicase activity / Hydrolases; Acting on peptide bonds (peptidases); Cysteine endopeptidases / single-stranded RNA binding / regulation of autophagy / host cell perinuclear region of cytoplasm / viral protein processing / lyase activity / host cell endoplasmic reticulum membrane / RNA helicase / symbiont-mediated suppression of host type I interferon-mediated signaling pathway / symbiont-mediated suppression of host gene expression / copper ion binding / viral translational frameshifting / symbiont-mediated activation of host autophagy / RNA-directed RNA polymerase / cysteine-type endopeptidase activity / viral RNA genome replication / RNA-directed RNA polymerase activity / DNA-templated transcription / lipid binding / host cell nucleus / SARS-CoV-2 activates/modulates innate and adaptive immune responses / ATP hydrolysis activity / proteolysis / RNA binding / zinc ion binding / ATP binding / membrane
Similarity search - Function
Nsp8 replicase, head domain / Viral (Superfamily 1) RNA helicase / RNA-dependent RNA polymerase, SARS-CoV-like / Nonstructural protein 14, betacoronavirus / NSP15, NendoU domain, coronavirus / Nonstructural protein 15, middle domain, alpha/betacoronavirus / Nonstructural protein 15, N-terminal domain, alpha/beta-coronavirus / NSP14, guanine-N7-methyltransferase domain, coronavirus / Coronavirus (CoV) guanine-N7-methyltransferase (N7-MTase) domain profile. / Coronavirus (CoV) Nsp15 N-terminal oligomerization domain profile. ...Nsp8 replicase, head domain / Viral (Superfamily 1) RNA helicase / RNA-dependent RNA polymerase, SARS-CoV-like / Nonstructural protein 14, betacoronavirus / NSP15, NendoU domain, coronavirus / Nonstructural protein 15, middle domain, alpha/betacoronavirus / Nonstructural protein 15, N-terminal domain, alpha/beta-coronavirus / NSP14, guanine-N7-methyltransferase domain, coronavirus / Coronavirus (CoV) guanine-N7-methyltransferase (N7-MTase) domain profile. / Coronavirus (CoV) Nsp15 N-terminal oligomerization domain profile. / NSP12 RNA-dependent RNA polymerase, coronavirus / : / Coronavirus Nsp12 RNA-dependent RNA polymerase (RdRp) domain profile. / Coronavirus Nsp12 Interface domain profile. / : / : / Coronavirus Nonstructural protein 13, 1B domain / Coronavirus Non-structural protein 13, zinc-binding domain / Coronavirus Nonstructural protein 13, stalk domain / Nidovirus 2-O-methyltransferase / Nidovirus 2'-O-methyltransferase (2'-O-MTase) domain profile. / Non-structural protein NSP15, N-terminal domain superfamily, coronavirus / Non-structural protein NSP15, middle domain superfamily / Coronavirus replicase NSP15, N-terminal oligomerization / Nonstructural protein 15, middle domain, coronavirus / Nonstructural protein 13, 1B domain, coronavirus / Coronavirus replicase NSP15, middle domain / Coronavirus replicase NSP15, N-terminal oligomerisation / Nidovirus 3'-5' exoribonuclease domain / Nidovirus 3'-5' exoribonuclease (ExoN) domain profile. / Non-structural protein NSP16, coronavirus-like / Non-structural protein 14, coronavirus / RNA polymerase, N-terminal, coronavirus / Coronavirus 2'-O-methyltransferase / Coronavirus proofreading exoribonuclease / Coronavirus RNA-dependent RNA polymerase, N-terminal / Nonstructural protein 13, zinc-binding domain, coronavirus-like / Coronaviridae zinc-binding (CV ZBD) domain profile. / Arterivirus Nsp11 N-terminal/Coronavirus NSP15 middle domain / Arterivirus Nsp11 N-terminal/coronavirus NSP15 middle (AV-Nsp11N/CoV-Nsp15M) domain profile. / Nidoviral uridylate-specific endoribonuclease (NendoU) domain profile. / Nidovirus RdRp-associated nucleotidyl transferase (NiRAN) domain / Nidovirus RdRp-associated nucleotidyl transferase (NiRAN) domain profile. / Endoribonuclease EndoU-like / NendoU domain, nidovirus / Coronavirus replicase NSP15, uridylate-specific endoribonuclease / : / Lipocalin signature. / DNA2/NAM7 helicase-like, C-terminal / AAA domain / (+) RNA virus helicase core domain / (+)RNA virus helicase core domain profile. / Non-structural protein NSP3, SUD-N (Mac2) domain, betacoronavirus / Sarbecovirus Nsp3c-N domain profile. / Non-structural protein NSP3, N-terminal, betacoronavirus / Polyprotein cleavage domain PL2pro superfamily, betacoronavirus / Non-structural protein NSP3, SUD-N (Mac2) domain superfamily, betacoronavirus / Betacoronavirus SUD-C domain / Betacoronavirus replicase NSP3, N-terminal / NSP1 globular domain superfamily, betacoronavirus / Non-structural protein 2, SARS-CoV-like / Carbamoyl-phosphate synthase subdomain signature 2. / Betacoronavirus Nsp3c-M domain profile. / NSP1, globular domain, betacoronavirus / Non-structural protein NSP3, SUD-M domain, betacoronavirus / Non-structural protein NSP3, SUD-M domain superfamily, betacoronavirus / Betacoronavirus replicase NSP1 / Betacoronavirus single-stranded poly(A) binding domain / NSP1, C-terminal domain, betacoronavirus / : / Betacoronavirus (BetaCoV) Nsp1 C-terminal domain profile. / Betacoronavirus Nsp3e group 2-specific marker (G2M) domain profile. / Betacoronavirus Nsp3c-C domain profile. / Betacoronavirus Nsp3e nucleic acid-binding (NAB) domain profile. / DPUP/SUD, C-terminal, betacoronavirus / Non-structural protein NSP3, nucleic acid-binding domain, betacoronavirus / Non-structural protein NSP3A domain-like superfamily / Non-structural protein NSP3, nucleic acid-binding domain superfamily, betacoronavirus / Non-structural protein 6, betacoronavirus / Betacoronavirus nucleic acid-binding (NAB) / Papain-like viral protease, palm and finger domains, coronavirus / Papain-like protease, N-terminal domain superfamily, coronavirus / Coronavirus replicase NSP2, N-terminal / : / Coronavirus replicase NSP2, C-terminal / Coronavirus (CoV) Nsp2 middle domain profile. / NSP1, globular domain, alpha/betacoronavirus / Coronavirus (CoV) Nsp1 globular domain profile. / Coronavirus (CoV) Nsp2 N-terminal domain profile. / Coronavirus (CoV) Nsp2 C-terminal domain profile. / Nonstructural protein 2, N-terminal domain, coronavirus / Non-structural protein 2, C-terminal domain, coronavirus / NSP3, second ubiquitin-like (Ubl) domain, coronavirus / Coronavirus Nsp3a Ubl domain profile. / Coronavirus Nsp3d Ubl domain profile. / NSP3, first ubiquitin-like (Ubl) domain, coronavirus / Peptidase family C16 domain profile. / : / : / Coronavirus replicase NSP7
Similarity search - Domain/homology
RNA / RNA (> 10) / Replicase polyprotein 1ab
Similarity search - Component
Biological speciesSevere acute respiratory syndrome coronavirus 2
MethodELECTRON MICROSCOPY / single particle reconstruction / cryo EM / Resolution: 2.9 Å
AuthorsYan, L. / Zhang, Y. / Ge, J. / Zheng, L. / Gao, Y. / Wang, T. / Jia, Z. / Wang, H. / Huang, Y. / Li, M. ...Yan, L. / Zhang, Y. / Ge, J. / Zheng, L. / Gao, Y. / Wang, T. / Jia, Z. / Wang, H. / Huang, Y. / Li, M. / Wang, Q. / Rao, Z. / Lou, Z.
Funding support China, 1items
OrganizationGrant numberCountry
Ministry of Science and Technology (MoST, China)2017YFC0840300 China
CitationJournal: Nat Commun / Year: 2020
Title: Architecture of a SARS-CoV-2 mini replication and transcription complex.
Authors: Liming Yan / Ying Zhang / Ji Ge / Litao Zheng / Yan Gao / Tao Wang / Zhihui Jia / Haofeng Wang / Yucen Huang / Mingyu Li / Quan Wang / Zihe Rao / Zhiyong Lou /
Abstract: Non-structural proteins (nsp) constitute the SARS-CoV-2 replication and transcription complex (RTC) to play a pivotal role in the virus life cycle. Here we determine the atomic structure of a SARS- ...Non-structural proteins (nsp) constitute the SARS-CoV-2 replication and transcription complex (RTC) to play a pivotal role in the virus life cycle. Here we determine the atomic structure of a SARS-CoV-2 mini RTC, assembled by viral RNA-dependent RNA polymerase (RdRp, nsp12) with a template-primer RNA, nsp7 and nsp8, and two helicase molecules (nsp13-1 and nsp13-2), by cryo-electron microscopy. Two groups of mini RTCs with different conformations of nsp13-1 are identified. In both of them, nsp13-1 stabilizes overall architecture of the mini RTC by contacting with nsp13-2, which anchors the 5'-extension of RNA template, as well as interacting with nsp7-nsp8-nsp12-RNA. Orientation shifts of nsp13-1 results in its variable interactions with other components in two forms of mini RTC. The mutations on nsp13-1:nsp12 and nsp13-1:nsp13-2 interfaces prohibit the enhancement of helicase activity achieved by mini RTCs. These results provide an insight into how helicase couples with polymerase to facilitate its function in virus replication and transcription.
History
DepositionSep 2, 2020Deposition site: PDBJ / Processing site: PDBJ
Revision 1.0Nov 4, 2020Provider: repository / Type: Initial release
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Assembly

Deposited unit
A: RNA-directed RNA polymerase
B: Non-structural protein 8
C: Non-structural protein 7
D: Non-structural protein 8
I: RNA (25-MER)
J: RNA (26-MER)
L: RNA (5'-R(P*UP*UP*UP*UP*UP*U)-3')
F: Helicase
E: Helicase
hetero molecules


Theoretical massNumber of molelcules
Total (without water)324,12017
Polymers323,5979
Non-polymers5238
Water00
1


  • Idetical with deposited unit
  • defined by author
  • Evidence: gel filtration
TypeNameSymmetry operationNumber
identity operation1_5551
Buried area22620 Å2
ΔGint-186 kcal/mol
Surface area118600 Å2

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Components

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Protein , 2 types, 3 molecules AFE

#1: Protein RNA-directed RNA polymerase / pp1ab / ORF1ab polyprotein / Pol / RdRp / Non-structural protein 12 / nsp12


Mass: 108161.477 Da / Num. of mol.: 1 / Fragment: UNP residues 4393-5324 / Mutation: D910N
Source method: isolated from a genetically manipulated source
Source: (gene. exp.) Severe acute respiratory syndrome coronavirus 2
Gene: rep, 1a-1b / Production host: Escherichia coli BL21(DE3) (bacteria) / Strain (production host): BL21(DE3) / References: UniProt: P0DTD1, RNA-directed RNA polymerase
#7: Protein Helicase / pp1ab / ORF1ab polyprotein / Hel / Non-structural protein 13 / nsp13


Mass: 66930.531 Da / Num. of mol.: 2 / Fragment: UNP residues 5325-5925
Source method: isolated from a genetically manipulated source
Source: (gene. exp.) Severe acute respiratory syndrome coronavirus 2
Gene: rep, 1a-1b / Production host: Escherichia coli BL21(DE3) (bacteria) / Strain (production host): BL21(DE3) / References: UniProt: P0DTD1, DNA helicase, RNA helicase

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Non-structural protein ... , 2 types, 3 molecules BDC

#2: Protein Non-structural protein 8 / pp1ab / ORF1ab polyprotein / nsp8


Mass: 21903.047 Da / Num. of mol.: 2 / Fragment: UNP residues 3943-4140
Source method: isolated from a genetically manipulated source
Source: (gene. exp.) Severe acute respiratory syndrome coronavirus 2
Gene: rep, 1a-1b / Production host: Escherichia coli BL21(DE3) (bacteria) / Strain (production host): BL21(DE3) / References: UniProt: P0DTD1
#3: Protein Non-structural protein 7 / pp1ab / ORF1ab polyprotein / nsp7


Mass: 9248.804 Da / Num. of mol.: 1 / Fragment: UNP residues 3860-3942
Source method: isolated from a genetically manipulated source
Source: (gene. exp.) Severe acute respiratory syndrome coronavirus 2
Gene: rep, 1a-1b / Production host: Escherichia coli BL21(DE3) (bacteria) / Strain (production host): BL21(DE3) / References: UniProt: P0DTD1

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RNA chain , 3 types, 3 molecules IJL

#4: RNA chain RNA (25-MER)


Mass: 8172.932 Da / Num. of mol.: 1 / Source method: obtained synthetically / Details: G
Source: (synth.) Severe acute respiratory syndrome coronavirus 2
#5: RNA chain RNA (26-MER)


Mass: 18461.963 Da / Num. of mol.: 1 / Source method: obtained synthetically
Source: (synth.) Severe acute respiratory syndrome coronavirus 2
#6: RNA chain RNA (5'-R(P*UP*UP*UP*UP*UP*U)-3')


Mass: 1884.197 Da / Num. of mol.: 1 / Source method: obtained synthetically
Source: (synth.) Severe acute respiratory syndrome coronavirus 2

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Non-polymers , 1 types, 8 molecules

#8: Chemical
ChemComp-ZN / ZINC ION


Mass: 65.409 Da / Num. of mol.: 8 / Source method: obtained synthetically / Formula: Zn / Feature type: SUBJECT OF INVESTIGATION

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Details

Has ligand of interestY
Has protein modificationN

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Experimental details

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Experiment

ExperimentMethod: ELECTRON MICROSCOPY
EM experimentAggregation state: 3D ARRAY / 3D reconstruction method: single particle reconstruction

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Sample preparation

Component
IDNameTypeEntity IDParent-IDSource
1nsp12-nsp7-nsp8-nsp13-RNACOMPLEX#1-#70MULTIPLE SOURCES
2nsp12-nsp7-nsp8-nsp13COMPLEX#1-#41RECOMBINANT
3RNACOMPLEX#5-#71MULTIPLE SOURCES
Source (natural)
IDEntity assembly-IDOrganismNcbi tax-ID
22Severe acute respiratory syndrome coronavirus 22697049
33Severe acute respiratory syndrome coronavirus 22697049
Source (recombinant)Organism: Escherichia coli BL21(DE3) (bacteria)
Buffer solutionpH: 7
SpecimenEmbedding applied: NO / Shadowing applied: NO / Staining applied: NO / Vitrification applied: YES
VitrificationCryogen name: NITROGEN

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Electron microscopy imaging

Experimental equipment
Model: Tecnai Polara / Image courtesy: FEI Company
MicroscopyModel: FEI POLARA 300
Electron gunElectron source: OTHER / Accelerating voltage: 300 kV / Illumination mode: OTHER
Electron lensMode: OTHER
Image recordingElectron dose: 60 e/Å2 / Film or detector model: GATAN K3 BIOQUANTUM (6k x 4k)

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Processing

SoftwareName: PHENIX / Version: 1.18rc3_3805: / Classification: refinement
EM softwareName: PHENIX / Category: model refinement
CTF correctionType: PHASE FLIPPING AND AMPLITUDE CORRECTION
3D reconstructionResolution: 2.9 Å / Resolution method: FSC 0.143 CUT-OFF / Num. of particles: 384727 / Num. of class averages: 83144 / Symmetry type: POINT
Refine LS restraints
Refine-IDTypeDev idealNumber
ELECTRON MICROSCOPYf_bond_d0.00721866
ELECTRON MICROSCOPYf_angle_d0.74829980
ELECTRON MICROSCOPYf_dihedral_angle_d10.5693479
ELECTRON MICROSCOPYf_chiral_restr0.0483465
ELECTRON MICROSCOPYf_plane_restr0.0053626

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