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Open data
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Basic information
| Entry | Database: PDB / ID: 28zv | ||||||||||||||||||
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| Title | human 48S PIC with mRNA (non-Kozak) | ||||||||||||||||||
Components |
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Keywords | RIBOSOME / translation initiation / Kozak sequence | ||||||||||||||||||
| Function / homology | Function and homology informationtranslation initiation ternary complex / regulation of translation in response to endoplasmic reticulum stress / glial limiting end-foot / response to manganese-induced endoplasmic reticulum stress / Cellular response to mitochondrial stress / positive regulation of type B pancreatic cell apoptotic process / HRI-mediated signaling / methionyl-initiator methionine tRNA binding / Response of EIF2AK1 (HRI) to heme deficiency / negative regulation of translational initiation in response to stress ...translation initiation ternary complex / regulation of translation in response to endoplasmic reticulum stress / glial limiting end-foot / response to manganese-induced endoplasmic reticulum stress / Cellular response to mitochondrial stress / positive regulation of type B pancreatic cell apoptotic process / HRI-mediated signaling / methionyl-initiator methionine tRNA binding / Response of EIF2AK1 (HRI) to heme deficiency / negative regulation of translational initiation in response to stress / PERK-mediated unfolded protein response / Recycling of eIF2:GDP / PERK regulates gene expression / response to kainic acid / eukaryotic translation initiation factor 2 complex / multi-eIF complex / regulation of translational initiation in response to stress / eukaryotic 43S preinitiation complex / translation factor activity, RNA binding / formation of translation preinitiation complex / eukaryotic 48S preinitiation complex / negative regulation of endoplasmic reticulum unfolded protein response / oxidized pyrimidine DNA binding / response to TNF agonist / positive regulation of base-excision repair / protein-synthesizing GTPase / positive regulation of intrinsic apoptotic signaling pathway in response to DNA damage / positive regulation of respiratory burst involved in inflammatory response / positive regulation of gastrulation / protein tyrosine kinase inhibitor activity / regulation of translational initiation / IRE1-RACK1-PP2A complex / positive regulation of Golgi to plasma membrane protein transport / nucleolus organization / TNFR1-mediated ceramide production / positive regulation of ubiquitin-protein transferase activity / positive regulation of DNA-templated transcription initiation / negative regulation of RNA splicing / negative regulation of DNA repair / erythrocyte homeostasis / supercoiled DNA binding / regulation of establishment of cell polarity / cysteine-type endopeptidase activator activity involved in apoptotic process / oxidized purine DNA binding / NF-kappaB complex / cytoplasmic translational initiation / rRNA modification in the nucleus and cytosol / negative regulation of intrinsic apoptotic signaling pathway in response to hydrogen peroxide / negative regulation of phagocytosis / negative regulation of bicellular tight junction assembly / ubiquitin-like protein conjugating enzyme binding / cytoplasmic side of rough endoplasmic reticulum membrane / Formation of the ternary complex, and subsequently, the 43S complex / laminin receptor activity / negative regulation of myoblast fusion / ion channel inhibitor activity / protein kinase A binding / positive regulation of mitochondrial depolarization / Ribosomal scanning and start codon recognition / PELO:HBS1L and ABCE1 dissociate a ribosome on a non-stop mRNA / Translation initiation complex formation / negative regulation of Wnt signaling pathway / fibroblast growth factor binding / ZNF598 and the Ribosome-associated Quality Trigger (RQT) complex dissociate a ribosome stalled on a no-go mRNA / Protein hydroxylation / TOR signaling / BH3 domain binding / negative regulation of translational frameshifting / iron-sulfur cluster binding / regulation of adenylate cyclase-activating G protein-coupled receptor signaling pathway / monocyte chemotaxis / mTORC1-mediated signalling / SARS-CoV-1 modulates host translation machinery / regulation of cell division / positive regulation of GTPase activity / Peptide chain elongation / cellular response to ethanol / Dengue Virus Attachment and Entry / Selenocysteine synthesis / Formation of a pool of free 40S subunits / negative regulation of protein binding / negative regulation of respiratory burst involved in inflammatory response / positive regulation of intrinsic apoptotic signaling pathway by p53 class mediator / Eukaryotic Translation Termination / protein serine/threonine kinase inhibitor activity / SRP-dependent cotranslational protein targeting to membrane / Response of EIF2AK4 (GCN2) to amino acid deficiency / negative regulation of ubiquitin-dependent protein catabolic process / ubiquitin ligase inhibitor activity / Viral mRNA Translation / endonucleolytic cleavage to generate mature 3'-end of SSU-rRNA from (SSU-rRNA, 5.8S rRNA, LSU-rRNA) / Nonsense Mediated Decay (NMD) independent of the Exon Junction Complex (EJC) / positive regulation of signal transduction by p53 class mediator / GTP hydrolysis and joining of the 60S ribosomal subunit / L13a-mediated translational silencing of Ceruloplasmin expression / mitophagy / Major pathway of rRNA processing in the nucleolus and cytosol / regulation of translational fidelity / positive regulation of microtubule polymerization / phagocytic cup Similarity search - Function | ||||||||||||||||||
| Biological species | Homo sapiens (human) | ||||||||||||||||||
| Method | ELECTRON MICROSCOPY / single particle reconstruction / cryo EM / Resolution: 2.9 Å | ||||||||||||||||||
Authors | von Loeffelholz, O. / Barchet, C. / Klaholz, B. | ||||||||||||||||||
| Funding support | France, 1items
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Citation | Journal: Nat Commun / Year: 2026Title: Translation initiation by the Kozak mRNA sequence is based on a conformational readout on the ribosome. Authors: Ottilie von Loeffelholz / Charles Barchet / Samuel Holvec / Aida Abou Ramadan / Cristina Protuc / Anne Maglott-Roth / S Nimali T de Silva / Isabelle Hazemann / Bruno P Klaholz / ![]() Abstract: The recognition mechanism of Kozak mRNA, typically comprising purines in the -3 and +4 positions flanking the AUG start codon, has remained enigmatic for decades. To address this fundamental function ...The recognition mechanism of Kozak mRNA, typically comprising purines in the -3 and +4 positions flanking the AUG start codon, has remained enigmatic for decades. To address this fundamental function in eukaryotes during translation initiation, we analysed several cryo-EM structures of human 48S preinitiation complexes with mRNA sequences differing in Kozak activity revealing distinct modes of recognition. The pre-codon triplet forms a fan-like intercalation into the 18S ribosomal RNA (rRNA), while a -3 pyrimidine destabilizes ternary complex positioning. Specificity towards the +4 purine is achieved beyond a single residue recognition by mutual conformational adaptations of eIF1A, mRNA and rRNA that involve the insertion of a reading head in which decoding residue A1825 (rRNA) stacks with the A-site codon to stabilize the fully accommodated state. Hence, instead of relying on base pairing as in bacteria, the specific recognition of the Kozak sequence on eukaryotic ribosomes is based on an induced-fit mechanism that triggers a conformational readout of the mRNA. | ||||||||||||||||||
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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 | 28zv.cif.gz | 2.1 MB | Display | PDBx/mmCIF format |
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| PDB format | pdb28zv.ent.gz | Display | PDB format | |
| PDBx/mmJSON format | 28zv.json.gz | Tree view | PDBx/mmJSON format | |
| Others | Other downloads |
-Validation report
| Arichive directory | https://data.pdbj.org/pub/pdb/validation_reports/8z/28zv ftp://data.pdbj.org/pub/pdb/validation_reports/8z/28zv | HTTPS FTP |
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-Related structure data
| Related structure data | ![]() 57005MC ![]() 28zuC ![]() 28zxC ![]() 28zyC M: map data used to model this data C: citing same article ( |
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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 S2BG
| #1: RNA chain | Mass: 603660.125 Da / Num. of mol.: 1 / Source method: isolated from a natural source / Source: (natural) Homo sapiens (human) |
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| #21: RNA chain | Mass: 15995.544 Da / Num. of mol.: 1 / Source method: obtained synthetically / Source: (synth.) Homo sapiens (human) |
| #40: RNA chain | Mass: 24543.787 Da / Num. of mol.: 1 / Source method: isolated from a natural source / Source: (natural) Homo sapiens (human) |
-Protein/peptide , 1 types, 1 molecules Ln
| #2: Protein/peptide | Mass: 3473.451 Da / Num. of mol.: 1 / Source method: isolated from a natural source / Source: (natural) Homo sapiens (human) / References: UniProt: P62945 |
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-Small ribosomal subunit protein ... , 4 types, 4 molecules SESLSTSZ
| #3: Protein | Mass: 29654.869 Da / Num. of mol.: 1 / Source method: isolated from a natural source / Source: (natural) Homo sapiens (human) / References: UniProt: P62701 |
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| #8: Protein | Mass: 18468.826 Da / Num. of mol.: 1 / Source method: isolated from a natural source / Source: (natural) Homo sapiens (human) / References: UniProt: P62280 |
| #34: Protein | Mass: 16104.579 Da / Num. of mol.: 1 / Source method: isolated from a natural source / Source: (natural) Homo sapiens (human) / References: UniProt: P39019 |
| #36: Protein | Mass: 13776.224 Da / Num. of mol.: 1 / Source method: isolated from a natural source / Source: (natural) Homo sapiens (human) / References: UniProt: P62851 |
+40S ribosomal protein ... , 26 types, 26 molecules SASBSHSISVSXSaSCSGSJSNSOSWSYSbSDSFSRSdScSKSMSUSQSSSP
-Protein , 4 types, 4 molecules SeSfSgH
| #20: Protein | Mass: 14415.724 Da / Num. of mol.: 1 / Source method: isolated from a natural source / Source: (natural) Homo sapiens (human) / References: UniProt: P62861 |
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| #24: Protein | Mass: 18004.041 Da / Num. of mol.: 1 / Source method: isolated from a natural source / Source: (natural) Homo sapiens (human) / References: UniProt: P62979 |
| #27: Protein | Mass: 35115.652 Da / Num. of mol.: 1 / Source method: isolated from a natural source / Source: (natural) Homo sapiens (human) / References: UniProt: P63244 |
| #41: Protein | Mass: 16488.449 Da / Num. of mol.: 1 Source method: isolated from a genetically manipulated source Source: (gene. exp.) Homo sapiens (human) / Gene: EIF1AX, EIF1A, EIF4C / Production host: ![]() |
-Eukaryotic translation initiation factor 2 subunit ... , 3 types, 3 molecules DEF
| #37: Protein | Mass: 36161.180 Da / Num. of mol.: 1 / Source method: isolated from a natural source / Source: (natural) Homo sapiens (human) / References: UniProt: P05198 |
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| #38: Protein | Mass: 51178.406 Da / Num. of mol.: 1 / Source method: isolated from a natural source / Source: (natural) Homo sapiens (human) / References: UniProt: P41091, protein-synthesizing GTPase |
| #39: Protein | Mass: 38454.484 Da / Num. of mol.: 1 / Source method: isolated from a natural source / Source: (natural) Homo sapiens (human) / References: UniProt: P20042 |
-Non-polymers , 6 types, 428 molecules 










| #42: Chemical | ChemComp-K / #43: Chemical | ChemComp-MG / #44: Chemical | #45: Chemical | ChemComp-GNP / | #46: Chemical | ChemComp-MET / | #47: Water | ChemComp-HOH / | |
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-Details
| Has ligand of interest | N |
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| Has protein modification | Y |
-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: 48S PIC / Type: RIBOSOME / Entity ID: #1-#41 / Source: NATURAL |
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| Source (natural) | Organism: Homo sapiens (human) |
| Buffer solution | pH: 7.5 |
| 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: FLOOD BEAM |
| Electron lens | Mode: BRIGHT FIELD / Nominal defocus max: 2500 nm / Nominal defocus min: 500 nm |
| Image recording | Electron dose: 40 e/Å2 / Film or detector model: TFS FALCON 4i (4k x 4k) |
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Processing
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| CTF correction | Type: PHASE FLIPPING AND AMPLITUDE CORRECTION | ||||||||||||||||||||||||
| 3D reconstruction | Resolution: 2.9 Å / Resolution method: FSC 0.143 CUT-OFF / Num. of particles: 39810 / Symmetry type: POINT | ||||||||||||||||||||||||
| Refinement | Highest resolution: 2.9 Å Stereochemistry target values: REAL-SPACE (WEIGHTED MAP SUM AT ATOM CENTERS) | ||||||||||||||||||||||||
| Refine LS restraints |
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About Yorodumi




Homo sapiens (human)
France, 1items
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