+
Open data
-
Basic information
| Entry | ![]() | ||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Title | Consensus volume for (Nap1)2-H2A-H2B-Kap114 structure | ||||||||||||||||||
Map data | |||||||||||||||||||
Sample |
| ||||||||||||||||||
Keywords | Histone / Chaperone / Import / Nucleosome Assembly / TRANSPORT PROTEIN | ||||||||||||||||||
| Biological species | ![]() | ||||||||||||||||||
| Method | single particle reconstruction / cryo EM / Resolution: 3.54 Å | ||||||||||||||||||
Authors | Jiou J / Fung HYJ / Chook YM | ||||||||||||||||||
| Funding support | United States, 5 items
| ||||||||||||||||||
Citation | Journal: J Cell Biol / Year: 2025Title: Nap1 and Kap114 co-chaperone H2A-H2B and facilitate targeted histone release in the nucleus. Authors: Ho Yee Joyce Fung / Jenny Jiou / Ashley B Niesman / Natalia E Bernardes / Yuh Min Chook / ![]() Abstract: Core histones, synthesized and processed in the cytoplasm, must be chaperoned as they are transported into the nucleus for nucleosome assembly. The importin Kap114 transports H2A-H2B into the yeast ...Core histones, synthesized and processed in the cytoplasm, must be chaperoned as they are transported into the nucleus for nucleosome assembly. The importin Kap114 transports H2A-H2B into the yeast nucleus, where RanGTP facilitates histone release. Kap114 and H2A-H2B also bind the histone chaperone Nap1, but how Nap1 and Kap114 cooperate in transport and nucleosome assembly remains unclear. Here, biochemical and structural analyses show that Kap114, H2A-H2B, and a Nap1 dimer (Nap12) associate in the absence and presence of RanGTP to form equimolar complexes. A previous study had shown that RanGTP reduces Kap114's ability to chaperone H2A-H2B, but a new cryo-EM structure of the Nap12•H2A-H2B•Kap114•RanGTP complex explains how both Kap114 and Nap12 interact with H2A-H2B, restoring its chaperoning within the assembly while effectively depositing it into nucleosomes. Together, our results suggest that Kap114 and Nap12 provide a sheltered path that facilitates the transfer of H2A-H2B from Kap114 to Nap12, ultimately directing its specific deposition into nucleosomes. | ||||||||||||||||||
| History |
|
-
Structure visualization
| Supplemental images |
|---|
-
Downloads & links
-EMDB archive
| Map data | emd_44140.map.gz | 209.8 MB | EMDB map data format | |
|---|---|---|---|---|
| Header (meta data) | emd-44140-v30.xml emd-44140.xml | 17.6 KB 17.6 KB | Display Display | EMDB header |
| Images | emd_44140.png | 60.7 KB | ||
| Filedesc metadata | emd-44140.cif.gz | 4.7 KB | ||
| Others | emd_44140_half_map_1.map.gz emd_44140_half_map_2.map.gz | 391.9 MB 391.9 MB | ||
| Archive directory | http://ftp.pdbj.org/pub/emdb/structures/EMD-44140 ftp://ftp.pdbj.org/pub/emdb/structures/EMD-44140 | HTTPS FTP |
-Validation report
| Summary document | emd_44140_validation.pdf.gz | 920.8 KB | Display | EMDB validaton report |
|---|---|---|---|---|
| Full document | emd_44140_full_validation.pdf.gz | 920.4 KB | Display | |
| Data in XML | emd_44140_validation.xml.gz | 17.6 KB | Display | |
| Data in CIF | emd_44140_validation.cif.gz | 20.7 KB | Display | |
| Arichive directory | https://ftp.pdbj.org/pub/emdb/validation_reports/EMD-44140 ftp://ftp.pdbj.org/pub/emdb/validation_reports/EMD-44140 | HTTPS FTP |
-Related structure data
-
Links
| EMDB pages | EMDB (EBI/PDBe) / EMDataResource |
|---|
-
Map
| File | Download / File: emd_44140.map.gz / Format: CCP4 / Size: 421.9 MB / Type: IMAGE STORED AS FLOATING POINT NUMBER (4 BYTES) | ||||||||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Projections & slices | Image control
Images are generated by Spider. | ||||||||||||||||||||||||||||||||||||
| Voxel size | X=Y=Z: 0.83 Å | ||||||||||||||||||||||||||||||||||||
| Density |
| ||||||||||||||||||||||||||||||||||||
| Symmetry | Space group: 1 | ||||||||||||||||||||||||||||||||||||
| Details | EMDB XML:
|
-Supplemental data
-Half map: #1
| File | emd_44140_half_map_1.map | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Projections & Slices |
| ||||||||||||
| Density Histograms |
-Half map: #2
| File | emd_44140_half_map_2.map | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Projections & Slices |
| ||||||||||||
| Density Histograms |
-
Sample components
-Entire : Crosslinked mixture of Kap114 with Nap1 and H2A-H2B
| Entire | Name: Crosslinked mixture of Kap114 with Nap1 and H2A-H2B |
|---|---|
| Components |
|
-Supramolecule #1: Crosslinked mixture of Kap114 with Nap1 and H2A-H2B
| Supramolecule | Name: Crosslinked mixture of Kap114 with Nap1 and H2A-H2B / type: complex / ID: 1 / Parent: 0 / Macromolecule list: #1-#4 Details: Nap1 and H2A-H2B were pre-complexed with excess histones, and Kap114 was added before mild crosslinking and SEC separation. |
|---|---|
| Source (natural) | Organism: ![]() |
| Molecular weight | Theoretical: 72 KDa |
-Experimental details
-Structure determination
| Method | cryo EM |
|---|---|
Processing | single particle reconstruction |
| Aggregation state | particle |
-
Sample preparation
| Concentration | 1.2 mg/mL | |||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Buffer | pH: 7.4 Component:
| |||||||||||||||
| Grid | Model: Quantifoil / Material: COPPER / Support film - Material: CARBON / Support film - topology: HOLEY | |||||||||||||||
| Vitrification | Cryogen name: ETHANE / Chamber humidity: 95 % / Chamber temperature: 280 K / Instrument: FEI VITROBOT MARK IV | |||||||||||||||
| Details | Crosslinked sample. |
-
Electron microscopy
| Microscope | FEI TITAN KRIOS |
|---|---|
| Specialist optics | Energy filter - Slit width: 20 eV |
| Image recording | Film or detector model: GATAN K3 (6k x 4k) / Number grids imaged: 1 / Number real images: 1080 / Average exposure time: 5.4 sec. / Average electron dose: 59.0 e/Å2 |
| Electron beam | Acceleration voltage: 300 kV / Electron source: FIELD EMISSION GUN |
| Electron optics | Illumination mode: FLOOD BEAM / Imaging mode: BRIGHT FIELD / Nominal defocus max: 2.4 µm / Nominal defocus min: 0.9 µm / Nominal magnification: 105000 |
| Sample stage | Specimen holder model: FEI TITAN KRIOS AUTOGRID HOLDER |
| Experimental equipment | ![]() Model: Titan Krios / Image courtesy: FEI Company |
Movie
Controller
About Yorodumi




Keywords
Authors
United States, 5 items
Citation












Z (Sec.)
Y (Row.)
X (Col.)




































Processing
FIELD EMISSION GUN
