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Open data
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Basic information
| Entry | Database: PDB / ID: 9n73 | |||||||||||||||
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| Title | SSU processome maturation and disassembly, State G | |||||||||||||||
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Keywords | RIBOSOME / SSU processome / ribosome assembly / RNA folding / RNA-protein interactions | |||||||||||||||
| Function / homology | Function and homology information18S rRNA (adenine1779-N6/adenine1780-N6)-dimethyltransferase / 18S rRNA (adenine(1779)-N(6)/adenine(1780)-N(6))-dimethyltransferase activity / nuclear polyadenylation-dependent antisense transcript catabolic process / nuclear polyadenylation-dependent snoRNA catabolic process / nuclear polyadenylation-dependent snRNA catabolic process / tRNA wobble cytosine modification / tRNA cytidine N4-acetyltransferase activity / rRNA acetylation involved in maturation of SSU-rRNA / 18S rRNA cytidine N-acetyltransferase activity / regulation of ribosomal protein gene transcription by RNA polymerase II ...18S rRNA (adenine1779-N6/adenine1780-N6)-dimethyltransferase / 18S rRNA (adenine(1779)-N(6)/adenine(1780)-N(6))-dimethyltransferase activity / nuclear polyadenylation-dependent antisense transcript catabolic process / nuclear polyadenylation-dependent snoRNA catabolic process / nuclear polyadenylation-dependent snRNA catabolic process / tRNA wobble cytosine modification / tRNA cytidine N4-acetyltransferase activity / rRNA acetylation involved in maturation of SSU-rRNA / 18S rRNA cytidine N-acetyltransferase activity / regulation of ribosomal protein gene transcription by RNA polymerase II / U1 snRNA 3'-end processing / tRNA acetylation / nuclear polyadenylation-dependent mRNA catabolic process / nuclear polyadenylation-dependent CUT catabolic process / U5 snRNA 3'-end processing / box H/ACA snoRNA binding / TRAMP-dependent tRNA surveillance pathway / RNA fragment catabolic process / exosome (RNase complex) / rRNA small subunit pseudouridine methyltransferase Nep1 / CURI complex / UTP-C complex / rRNA 2'-O-methylation / Noc4p-Nop14p complex / endonucleolytic cleavage in ITS1 upstream of 5.8S rRNA from tricistronic rRNA transcript (SSU-rRNA, 5.8S rRNA, LSU-rRNA) / U4 snRNA 3'-end processing / nuclear polyadenylation-dependent rRNA catabolic process / poly(A)-dependent snoRNA 3'-end processing / t-UTP complex / nuclear exosome (RNase complex) / Pwp2p-containing subcomplex of 90S preribosome / nuclear microtubule / Mpp10 complex / rRNA (pseudouridine) methyltransferase activity / exonucleolytic trimming to generate mature 3'-end of 5.8S rRNA from tricistronic rRNA transcript (SSU-rRNA, 5.8S rRNA, LSU-rRNA) / box C/D sno(s)RNA binding / snoRNA guided rRNA 2'-O-methylation / rRNA modification / histone H2AQ104 methyltransferase activity / septum digestion after cytokinesis / regulation of rRNA processing / rRNA (adenine-N6,N6-)-dimethyltransferase activity / tRNA re-export from nucleus / snRNA binding / histone mRNA catabolic process / RNA folding chaperone / box C/D sno(s)RNA 3'-end processing / nuclear mRNA surveillance / rRNA methyltransferase activity / rDNA heterochromatin / endonucleolytic cleavage in 5'-ETS of tricistronic rRNA transcript (SSU-rRNA, 5.8S rRNA, LSU-rRNA) / endonucleolytic cleavage of tricistronic rRNA transcript (SSU-rRNA, 5.8S rRNA, LSU-rRNA) / post-transcriptional tethering of RNA polymerase II gene DNA at nuclear periphery / maturation of SSU-rRNA from tricistronic rRNA transcript (SSU-rRNA, LSU-rRNA,5S) / regulation of transcription by RNA polymerase I / endonucleolytic cleavage to generate mature 5'-end of SSU-rRNA from (SSU-rRNA, 5.8S rRNA, LSU-rRNA) / box C/D methylation guide snoRNP complex / U4/U6 snRNP / positive regulation of rRNA processing / tRNA export from nucleus / single-stranded telomeric DNA binding / rRNA primary transcript binding / small nuclear ribonucleoprotein complex / sno(s)RNA-containing ribonucleoprotein complex / rRNA base methylation / : / O-methyltransferase activity / U4 snRNA binding / SUMOylation of RNA binding proteins / protein localization to nucleolus / 90S preribosome assembly / rRNA methylation / mTORC1-mediated signalling / Protein hydroxylation / RNA catabolic process / mRNA modification / U4 snRNP / regulation of telomere maintenance / U3 snoRNA binding / poly(U) RNA binding / positive regulation of nuclear-transcribed mRNA catabolic process, deadenylation-dependent decay / Formation of the ternary complex, and subsequently, the 43S complex / Translation initiation complex formation / poly(A)+ mRNA export from nucleus / precatalytic spliceosome / Ribosomal scanning and start codon recognition / preribosome, small subunit precursor / snoRNA binding / Major pathway of rRNA processing in the nucleolus and cytosol / establishment of cell polarity / spliceosomal complex assembly / positive regulation of transcription by RNA polymerase I / SRP-dependent cotranslational protein targeting to membrane / GTP hydrolysis and joining of the 60S ribosomal subunit / nucleolar large rRNA transcription by RNA polymerase I / Formation of a pool of free 40S subunits / Nonsense Mediated Decay (NMD) independent of the Exon Junction Complex (EJC) / Nonsense Mediated Decay (NMD) enhanced by the Exon Junction Complex (EJC) / L13a-mediated translational silencing of Ceruloplasmin expression / 90S preribosome Similarity search - Function | |||||||||||||||
| Biological species | ![]() | |||||||||||||||
| Method | ELECTRON MICROSCOPY / single particle reconstruction / cryo EM / Resolution: 5.96 Å | |||||||||||||||
Authors | Buzovetsky, O. / Klinge, S. | |||||||||||||||
| Funding support | United States, 2items
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Citation | Journal: Nature / Year: 2025Title: Helicase-mediated mechanism of SSU processome maturation and disassembly. Authors: Olga Buzovetsky / Sebastian Klinge / ![]() Abstract: Eukaryotic ribosomal small subunit (SSU) assembly requires the SSU processome, a nucleolar precursor containing the RNA chaperone U3 small nucleolar RNA (snoRNA). The underlying molecular mechanisms ...Eukaryotic ribosomal small subunit (SSU) assembly requires the SSU processome, a nucleolar precursor containing the RNA chaperone U3 small nucleolar RNA (snoRNA). The underlying molecular mechanisms of SSU processome maturation, remodelling, disassembly and RNA quality control, and the transitions between states remain unknown owing to a paucity of intermediates. Here we report 16 native SSU processome structures alongside genetic data, revealing how two helicases, the Mtr4-exosome and Dhr1, are controlled for accurate and unidirectional ribosome biogenesis. Our data show how irreversible pre-ribosomal RNA degradation by the redundantly tethered RNA exosome couples the transformation of the SSU processome into a pre-40S particle, during which Utp14 can probe evolving surfaces, ultimately positioning and activating Dhr1 to unwind the U3 snoRNA and initiate nucleolar pre-40S release. This study highlights a paradigm for large dynamic RNA-protein complexes in which irreversible RNA degradation drives compositional changes and communicates these changes to govern enzyme activity while maintaining overall quality control. | |||||||||||||||
| History |
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Structure visualization
| Structure viewer | Molecule: Molmil Jmol/JSmol |
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Downloads & links
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Download
| PDBx/mmCIF format | 9n73.cif.gz | 4.5 MB | Display | PDBx/mmCIF format |
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| PDB format | pdb9n73.ent.gz | Display | PDB format | |
| PDBx/mmJSON format | 9n73.json.gz | Tree view | PDBx/mmJSON format | |
| Others | Other downloads |
-Validation report
| Summary document | 9n73_validation.pdf.gz | 1.9 MB | Display | wwPDB validaton report |
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| Full document | 9n73_full_validation.pdf.gz | 1.9 MB | Display | |
| Data in XML | 9n73_validation.xml.gz | 485.8 KB | Display | |
| Data in CIF | 9n73_validation.cif.gz | 880.7 KB | Display | |
| Arichive directory | https://data.pdbj.org/pub/pdb/validation_reports/n7/9n73 ftp://data.pdbj.org/pub/pdb/validation_reports/n7/9n73 | HTTPS FTP |
-Related structure data
| Related structure data | ![]() 49083MC ![]() 9n6vC ![]() 9n6wC ![]() 9n6xC ![]() 9n6yC ![]() 9n6zC ![]() 9n70C ![]() 9n74C ![]() 9n75C ![]() 9n76C ![]() 9n77C ![]() 9n7aC ![]() 9n7bC C: citing same article ( M: map data used to model this data |
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| Similar structure data | Similarity search - Function & homology F&H Search |
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Links
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Assembly
| Deposited unit | ![]()
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Components
+RNA chain , 3 types, 3 molecules L0L1L2
+40S ribosomal protein ... , 18 types, 18 molecules L3L4L5L6L7L8L9LCLDLELFLGNFNGNPNQOHSR
+Protein , 19 types, 23 molecules LHLOLULXLYNBNDNLNMNNNSNVOAOUSCSDSESFSHSJSKSWSZ
+U3 small nucleolar RNA-associated protein ... , 17 types, 17 molecules LILJLKLLLMLNLPLQLRLSLTLWNANHSPSSSY
+Ribosome biogenesis protein ... , 2 types, 2 molecules LVSI
+U3 small nucleolar ribonucleoprotein protein ... , 3 types, 3 molecules LZNCSM
+Ribosomal RNA-processing protein ... , 2 types, 2 molecules NISG
+Nucleolar protein ... , 2 types, 2 molecules SASB
+RRNA-processing protein ... , 2 types, 2 molecules SLSQ
+Nucleolar complex protein ... , 2 types, 2 molecules STSU
+Details
-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: SSU processome maturation and disassembly, State G / Type: COMPLEX / Entity ID: all / Source: NATURAL | ||||||||||||||||||||||||||||
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| Source (natural) | Organism: ![]() | ||||||||||||||||||||||||||||
| Buffer solution | pH: 7.5 | ||||||||||||||||||||||||||||
| Buffer component |
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| Specimen | Embedding applied: NO / Shadowing applied: NO / Staining applied: NO / Vitrification applied: YES | ||||||||||||||||||||||||||||
| Vitrification | 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: TFS KRIOS |
| Electron gun | Electron source: FIELD EMISSION GUN / Accelerating voltage: 300 kV / Illumination mode: OTHER |
| Electron lens | Mode: BRIGHT FIELD / Nominal defocus max: 25000 nm / Nominal defocus min: 1000 nm |
| Image recording | Electron dose: 60 e/Å2 / Film or detector model: GATAN K3 (6k x 4k) |
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Processing
| CTF correction | Type: PHASE FLIPPING AND AMPLITUDE CORRECTION |
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| 3D reconstruction | Resolution: 5.96 Å / Resolution method: FSC 0.143 CUT-OFF / Num. of particles: 4987 / Symmetry type: POINT |
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About Yorodumi






United States, 2items
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FIELD EMISSION GUN