Table 1:
Cryo-EM data collection, refinement and validation statistics
| Active State: 2:1 complex (EMD-9384) (PDB 6NJ9) | Active State: 1:1 complex (EMD-0480) (PDB 6NQA) | Poised State (EMD-0468) (PDB 6NOG) | |
|---|---|---|---|
| Data collection and processing | |||
| Magnification | 130,000 | 130,000 | 130,000 |
| Voltage (kV) | 300 | 300 | 300 |
| Electron exposure (e–/Å2) | 50 | 50 | 50 |
| Defocus range (μm) | −1 to −2.5 | −1 to −2.5 | −1 to −2.5 |
| Pixel size (Å) | 0.532 | 0.532 | 0.532 |
| Symmetry imposed | C2 | ||
| Initial particle images (no.) | 800727 | 800727 | 868027 |
| Final particle images (no.) | 237780 | 220681 | 108658 |
| Map resolution (Å) | 2.96 | 3.54 | 3.9 |
| FSC threshold | (0.143) | (0.143) | (0.143) |
| Refinement | |||
| Initial model used (PDB code) | 1KX3, 1NW3, 1UBQ | 1KX3, 1NW3, 1UBQ | 1KX3, 3QOW 1UBQ |
| Model resolution (Å) | 3.2 | 4.0 | 4.4 |
| FSC threshold | (0.5) | (0.5) | (0.5) |
| Model resolution range (Å) | 272.4-3.3 | 272.4-4.0 | 272.4-4.4 |
| Map sharpening B factor (Å2) | −73 | −96.5 | −180 |
| Model composition | |||
| Non-hydrogen atoms | 15510 | 15322 | 14957 |
| Protein residues | 1186 | 1164 | 1126 |
| Nucleotides | 292 | 292 | 292 |
| Ligands | 1 | 1 | 0 |
| B factors (Å2) | |||
| Protein | 71.6 | 72.8 | 113.1 |
| Nucleotide | 19.47 | 24.5 | 134.4 |
| Ligand | 77.42 | 68.1 | - |
| R.m.s. deviations | |||
| Bond lengths (Å) | 0.013 | 0.007 | 0.009 |
| Bond angles (°) | 1.04 | 0.853 | 1.35 |
| Validation | |||
| MolProbity score | 1.46 | 1.59 | 1.41 |
| Clashscore | 2.72 | 4.11 | 4.29 |
| Poor rotamers (%) | 0.99 | 0.51 | 0.94 |
| Ramachandran plot | |||
| Favored (%) | 94.08 | 94.23 | 96.73 |
| Allowed (%) | 5.92 | 5.77 | 3.27 |
| Disallowed (%) | 0 | 0 | 0 |