6QJQ
Cryo-EM structure of heparin-induced 2N3R tau filaments
ELECTRON MICROSCOPY
| Sample |
|---|
| heparin-induced 2N3R tau filaments |
| Specimen Preparation | |
|---|---|
| Sample Aggregation State | FILAMENT |
| Vitrification Instrument | FEI VITROBOT MARK IV |
| Cryogen Name | ETHANE |
| Sample Vitrification Details | Blot force: -12 ; Blot time: 4s |
| 3D Reconstruction | |
|---|---|
| Reconstruction Method | SINGLE PARTICLE |
| Number of Particles | 149909 |
| Reported Resolution (Å) | 3.7 |
| Resolution Method | FSC 0.143 CUT-OFF |
| Other Details | For masked FSC calculation, phase randomisation was done at 6.1 A, where the FSC of the unmasked map was 0.85. |
| Refinement Type | |
| Symmetry Type | HELICAL |
| Axial Symmetry | C1 |
| Axial Rise | 4.7 |
| Angular Rotation | -1.05 |
| Map-Model Fitting and Refinement | |||||
|---|---|---|---|---|---|
| Id | 1 | ||||
| Refinement Space | RECIPROCAL | ||||
| Refinement Protocol | AB INITIO MODEL | ||||
| Refinement Target | Fourier shell correlation | ||||
| Overall B Value | 95.9 | ||||
| Fitting Procedure | |||||
| Details | A stack of three consecutive monomers was refined to preserve nearest-neighbour interactions for the middle chain. Side-chain clashes were detected us ... | ||||
| Data Acquisition | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Detector Type | GATAN K2 SUMMIT (4k x 4k) | ||||||||
| Electron Dose (electrons/Å**2) | 1.134 | ||||||||
| Imaging Experiment | 1 |
|---|---|
| Date of Experiment | |
| Temperature (Kelvin) | |
| Microscope Model | FEI TITAN KRIOS |
| Minimum Defocus (nm) | 800 |
| Maximum Defocus (nm) | 2200 |
| Minimum Tilt Angle (degrees) | |
| Maximum Tilt Angle (degrees) | |
| Nominal CS | 2.7 |
| Imaging Mode | BRIGHT FIELD |
| Specimen Holder Model | FEI TITAN KRIOS AUTOGRID HOLDER |
| Nominal Magnification | |
| Calibrated Magnification | |
| Source | FIELD EMISSION GUN |
| Acceleration Voltage (kV) | 300 |
| Imaging Details |
| EM Software | ||
|---|---|---|
| Task | Software Package | Version |
| PARTICLE SELECTION | RELION | 3.0 |
| IMAGE ACQUISITION | EPU | 1.10.0.77REL |
| CTF CORRECTION | CTFFIND | 4.1 |
| MODEL FITTING | Coot | 0.8.9.1 |
| INITIAL EULER ASSIGNMENT | RELION | 3.0 |
| FINAL EULER ASSIGNMENT | RELION | 3.0 |
| CLASSIFICATION | RELION | 3.0 |
| RECONSTRUCTION | RELION | 3.0 |
| MODEL REFINEMENT | REFMAC | 5.8.0236 |
| MODEL REFINEMENT | PHENIX | dev-2919-000 |
| Image Processing | ||||
|---|---|---|---|---|
| CTF Correction Type | CTF Correction Details | Number of Particles Selected | Particle Selection Details | |
| PHASE FLIPPING AND AMPLITUDE CORRECTION | Aligned, non-dose-weighted micrographs were used to estimate the contrast transfer function (CTF) using CTFFIND4.1 | 788359 | Manually picked | |
