ELECTRON MICROSCOPY


Sample

Native purified Nucleosome Elongation Complex from Drosophila melanogaster

Specimen Preperation
Sample Aggregation State PARTICLE
Vitrification Instrument FEI VITROBOT MARK IV
Cryogen Name ETHANE
Sample Vitrification Details ?
3D Reconstruction
Reconstruction Method SINGLE PARTICLE
Number of Particles 36552
Reported Resolution (Å) 7.8
Resolution Method FSC 0.143 CUT-OFF
Other Details The Nucleosome EC was refined to an overall resolution of 7.8 A. Then, local refinement was performed with an indvidual focus on the nucleosome and Pol II. This entry represents a composite map of the two locally refined entities.
Refinement Type
Symmetry Type POINT
Map-Model Fitting and Refinement
ID 1
Refinement Space ?
Refinement Protocol AB INITIO MODEL
Refinement Target ?
Overall B Value 50
Fitting Procedure ?
Details The model was based on individual models from this study: octameric nucleosome and Pol II. The models were rigid-body fit into the composite structure, connected and fixed in Coot and Phenix.
Data Acquisition
Detector Type FEI FALCON IV (4k x 4k)
Electron Dose (electrons/Å2) 50.65
Imaging Experiment
Date of Experiment ?
Temprature (Kelvin)
Microscope Model TFS TALOS
Minimum Defocus (nm) 1000
Maximum Defocus (nm) 2500
Minimum Tilt Angle (degrees) ?
Maximum Tilt Angle (degrees) ?
Nominal CS ?
Imaging Mode BRIGHT FIELD
Specimen Holder Model FEI TITAN KRIOS AUTOGRID HOLDER
Nominal Magnification ?
Calibrated Magnification ?
Source FIELD EMISSION GUN
Acceleration Voltage (kV) 200
Imaging Details ?
Imaging Experiment
Task Software Package Version
PARTICLE SELECTION cryoSPARC 4.3.1
IMAGE ACQUISITION EPU 3.4
CTF CORRECTION cryoSPARC 4.3.1
MODEL FITTING UCSF ChimeraX 1.8
INITIAL EULER ASSIGNMENT cryoSPARC 4.3.1
FINAL EULER ASSIGNMENT cryoSPARC 4.3.1
RECONSTRUCTION cryoSPARC 4.3.1
MODEL REFINEMENT Coot 0.9.8.7
MODEL REFINEMENT PHENIX 1.21.5207
Image Processing
CTF Correction Type CTF Correction Details Number of Particles Selected Particle Selection Details
PHASE FLIPPING AND AMPLITUDE CORRECTION 'Patch CTF Estimation' in cryoSPARC