Cryo-EM structure of the human SK2-4 chimera/calmodulin channel complex in the Ca2+ free state
ELECTRON MICROSCOPY
Starting Model(s)
| Initial Refinement Model(s) | |||
|---|---|---|---|
| Type | Source | Accession Code | Details |
| experimental model | PDB | 9O48 | |
Refinement
| RMS Deviations | |
|---|---|
| Key | Refinement Restraint Deviation |
| f_dihedral_angle_d | 3.03 |
| f_angle_d | 0.314 |
| f_chiral_restr | 0.033 |
| f_plane_restr | 0.002 |
| f_bond_d | 0.001 |
| Sample |
|---|
| Ternary complex of human SK2-4 chimera/calmodulin channel complex in the Ca2+-free state |
| Sample Components |
| Human SK2-4 chimeric channel |
| Human calmodulin |
| Specimen Preparation | |
|---|---|
| Sample Aggregation State | PARTICLE |
| Vitrification Instrument | FEI VITROBOT MARK IV |
| Cryogen Name | ETHANE |
| Sample Vitrification Details | 5 uL of sample was applied to grids at 4 degree temperature with 100% humidity. After 30 seconds, grids were blotted for 5 seconds with blot force 25 ... |
| 3D Reconstruction | |
|---|---|
| Reconstruction Method | SINGLE PARTICLE |
| Number of Particles | 386845 |
| Reported Resolution (Å) | 3.4 |
| Resolution Method | FSC 0.143 CUT-OFF |
| Other Details | |
| Refinement Type | |
| Symmetry Type | POINT |
| Point Symmetry | C4 |
| Map-Model Fitting and Refinement | |||||
|---|---|---|---|---|---|
| Id | 1 (9O48) | ||||
| Refinement Space | REAL | ||||
| Refinement Protocol | |||||
| Refinement Target | |||||
| Overall B Value | |||||
| Fitting Procedure | |||||
| Details | |||||
| Data Acquisition | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Detector Type | FEI FALCON IV (4k x 4k) | ||||||||
| Electron Dose (electrons/Å**2) | 50 | ||||||||
| Imaging Experiment | 1 |
|---|---|
| Date of Experiment | |
| Temperature (Kelvin) | |
| Microscope Model | TFS KRIOS |
| Minimum Defocus (nm) | 800 |
| Maximum Defocus (nm) | 1600 |
| Minimum Tilt Angle (degrees) | |
| Maximum Tilt Angle (degrees) | |
| Nominal CS | 0.01 |
| Imaging Mode | BRIGHT FIELD |
| Specimen Holder Model | FEI TITAN KRIOS AUTOGRID HOLDER |
| Nominal Magnification | 75000 |
| Calibrated Magnification | |
| Source | FIELD EMISSION GUN |
| Acceleration Voltage (kV) | 300 |
| Imaging Details |
| EM Software | ||
|---|---|---|
| Task | Software Package | Version |
| PARTICLE SELECTION | cryoSPARC | |
| IMAGE ACQUISITION | EPU | |
| MODEL FITTING | PHENIX | 1.21.2_5419 |
| INITIAL EULER ASSIGNMENT | cryoSPARC | |
| FINAL EULER ASSIGNMENT | cryoSPARC | |
| CLASSIFICATION | cryoSPARC | |
| RECONSTRUCTION | cryoSPARC | |
| MODEL REFINEMENT | PHENIX | 1.21.2_5419 |
| Image Processing | ||||
|---|---|---|---|---|
| CTF Correction Type | CTF Correction Details | Number of Particles Selected | Particle Selection Details | |
| PHASE FLIPPING AND AMPLITUDE CORRECTION | 8200000 | |||
