+Open data
-Basic information
Entry | Database: EMDB / ID: EMD-23438 | ||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Title | Tetrahymena telomerase T4D4 structure at 4.4 Angstrom | ||||||||||||
Map data | Tetrahymena telomerase T4D4 structure | ||||||||||||
Sample |
| ||||||||||||
Function / homology | Function and homology information telomerase catalytic core complex assembly / telomerase RNA stabilization / : / DNA replication factor A complex / single-stranded telomeric DNA binding / telomerase RNA binding / telomerase holoenzyme complex / telomeric DNA binding / telomere maintenance via telomerase / RNA-directed DNA polymerase ...telomerase catalytic core complex assembly / telomerase RNA stabilization / : / DNA replication factor A complex / single-stranded telomeric DNA binding / telomerase RNA binding / telomerase holoenzyme complex / telomeric DNA binding / telomere maintenance via telomerase / RNA-directed DNA polymerase / DNA recombination / DNA replication / chromosome, telomeric region / DNA repair / DNA binding / zinc ion binding / metal ion binding Similarity search - Function | ||||||||||||
Biological species | Tetrahymena thermophila (eukaryote) | ||||||||||||
Method | single particle reconstruction / cryo EM / Resolution: 4.4 Å | ||||||||||||
Authors | He Y / Wang Y / Liu B / Helmling C / Susac L / Cheng R / Zhou ZH / Feigon J | ||||||||||||
Funding support | United States, 3 items
| ||||||||||||
Citation | Journal: Nature / Year: 2021 Title: Structures of telomerase at several steps of telomere repeat synthesis. Authors: Yao He / Yaqiang Wang / Baocheng Liu / Christina Helmling / Lukas Sušac / Ryan Cheng / Z Hong Zhou / Juli Feigon / Abstract: Telomerase is unique among the reverse transcriptases in containing a noncoding RNA (known as telomerase RNA (TER)) that includes a short template that is used for the processive synthesis of G-rich ...Telomerase is unique among the reverse transcriptases in containing a noncoding RNA (known as telomerase RNA (TER)) that includes a short template that is used for the processive synthesis of G-rich telomeric DNA repeats at the 3' ends of most eukaryotic chromosomes. Telomerase maintains genomic integrity, and its activity or dysregulation are critical determinants of human longevity, stem cell renewal and cancer progression. Previous cryo-electron microscopy structures have established the general architecture, protein components and stoichiometries of Tetrahymena and human telomerase, but our understandings of the details of DNA-protein and RNA-protein interactions and of the mechanisms and recruitment involved remain limited. Here we report cryo-electron microscopy structures of active Tetrahymena telomerase with telomeric DNA at different steps of nucleotide addition. Interactions between telomerase reverse transcriptase (TERT), TER and DNA reveal the structural basis of the determination of the 5' and 3' template boundaries, handling of the template-DNA duplex and separation of the product strand during nucleotide addition. The structure and binding interface between TERT and telomerase protein p50 (a homologue of human TPP1) define conserved interactions that are required for telomerase activation and recruitment to telomeres. Telomerase La-related protein p65 remodels several regions of TER, bridging the 5' and 3' ends and the conserved pseudoknot to facilitate assembly of the TERT-TER catalytic core. | ||||||||||||
History |
|
-Structure visualization
Movie |
Movie viewer |
---|---|
Structure viewer | EM map: SurfViewMolmilJmol/JSmol |
Supplemental images |
-Downloads & links
-EMDB archive
Map data | emd_23438.map.gz | 49.6 MB | EMDB map data format | |
---|---|---|---|---|
Header (meta data) | emd-23438-v30.xml emd-23438.xml | 9.6 KB 9.6 KB | Display Display | EMDB header |
Images | emd_23438.png | 100.7 KB | ||
Archive directory | http://ftp.pdbj.org/pub/emdb/structures/EMD-23438 ftp://ftp.pdbj.org/pub/emdb/structures/EMD-23438 | HTTPS FTP |
-Validation report
Summary document | emd_23438_validation.pdf.gz | 341.7 KB | Display | EMDB validaton report |
---|---|---|---|---|
Full document | emd_23438_full_validation.pdf.gz | 341.3 KB | Display | |
Data in XML | emd_23438_validation.xml.gz | 6 KB | Display | |
Arichive directory | https://ftp.pdbj.org/pub/emdb/validation_reports/EMD-23438 ftp://ftp.pdbj.org/pub/emdb/validation_reports/EMD-23438 | HTTPS FTP |
-Related structure data
-Links
EMDB pages | EMDB (EBI/PDBe) / EMDataResource |
---|---|
Related items in Molecule of the Month |
-Map
File | Download / File: emd_23438.map.gz / Format: CCP4 / Size: 64 MB / Type: IMAGE STORED AS FLOATING POINT NUMBER (4 BYTES) | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Annotation | Tetrahymena telomerase T4D4 structure | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Projections & slices | Image control
Images are generated by Spider. | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Voxel size | X=Y=Z: 1.36 Å | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Density |
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Symmetry | Space group: 1 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Details | EMDB XML:
CCP4 map header:
|
-Supplemental data
-Sample components
-Entire : Tetrahymena telomerase T4D4 structure
Entire | Name: Tetrahymena telomerase T4D4 structure |
---|---|
Components |
|
-Supramolecule #1: Tetrahymena telomerase T4D4 structure
Supramolecule | Name: Tetrahymena telomerase T4D4 structure / type: complex / ID: 1 / Parent: 0 / Macromolecule list: #1-#8 |
---|---|
Source (natural) | Organism: Tetrahymena thermophila (eukaryote) |
-Experimental details
-Structure determination
Method | cryo EM |
---|---|
Processing | single particle reconstruction |
Aggregation state | particle |
-Sample preparation
Buffer | pH: 8 |
---|---|
Vitrification | Cryogen name: ETHANE |
-Electron microscopy
Microscope | FEI TITAN KRIOS |
---|---|
Image recording | Film or detector model: GATAN K2 SUMMIT (4k x 4k) / Detector mode: SUPER-RESOLUTION / Average electron dose: 48.0 e/Å2 |
Electron beam | Acceleration voltage: 300 kV / Electron source: FIELD EMISSION GUN |
Electron optics | Illumination mode: FLOOD BEAM / Imaging mode: BRIGHT FIELD |
Experimental equipment | Model: Titan Krios / Image courtesy: FEI Company |
-Image processing
Final reconstruction | Resolution.type: BY AUTHOR / Resolution: 4.4 Å / Resolution method: FSC 0.143 CUT-OFF / Number images used: 28297 |
---|---|
Initial angle assignment | Type: MAXIMUM LIKELIHOOD |
Final angle assignment | Type: MAXIMUM LIKELIHOOD |