Table 1.
Kinetic parameters of single vesicle fusion events
| Dataset A | |||||
|---|---|---|---|---|---|
| Genotype | munc18-1 +/+ or munc18-1 +/− | munc18-1 −/− | munc18-1 −/− | munc18-1 −/− | munc18-1 −/− |
| Overexpression | Untransfected | Untransfected | Munc18-1 WT | Munc18-2 WT | Munc18-1 NV |
| Number of cells | 17 | 12 | 17 | 18 | 17 |
| Analyzed fusion events | 905 | 562 | 1155 | 1102 | 777 |
| Amplitude (pA) | 53 ± 3 | 61 ± 6 | 56 ± 4 | 63 ± 5 | 65 ± 7 |
| Half-width (ms) | 2.1 ± 0.2 | 2.2 ± 0.2 | 2.3 ± 0.2 | 2.0 ± 0.3 | 2.1 ± 0.2 |
| 10–90% rise time (ms) | 0.43 ± 0.02 | 0.41 ± 0.03 | 0.41 ± 0.02 | 0.39 ± 0.03 | 0.40 ± 0.01 |
| Foot duration (ms) | 2.4 ± 0.2 | 1.8 ± 0.2 | 2.0 ± 0.2 | 2.0 ± 0.2 | 2.1 ± 0.3 |
| Dataset B |
Dataset C |
||||
| Genotype | munc18-1 −/− | munc18-1 −/− | munc18-1 +/+ (bovine cells) | munc18-1 +/+ (bovine cells) | |
| Overexpression | Munc18-1 R39C | Munc18-1 WT | Munc18-1 R39C | Munc18-1 WT | |
| Number of cells | 26 | 23 | 25 | 25 | |
| Analyzed fusion events | 1857 | 1590 | 1132 | 1218 | |
| Amplitude (pA) | 67 ± 4 | 61 ± 4 | 170 ± 20 | 140 ± 20 | |
| Half-width (ms) | 2.6 ± 0.3 | 2.8 ± 0.3 | 9 ± 1 | 10 ± 1 | |
| 10–90% rise time (ms) | 0.54 ± 0.05 | 0.52 ± 0.03 | 1.2 ± 0.1 | 1.3 ± 0.2 | |
| Foot duration (ms) | 2.8 ± 0.2 | 2.9 ± 0.2 | 3.5 ± 0.4 | 4.3 ± 0.5 | |
Medians from ≥50 events per cell were calculated. Shown here is the mean ± SEM of the cell medians within each group. The two-step data pooling strategy takes cell-to-cell variability into account. No significant differences were found (at α = 0.05) in any parameters after pairwise comparison (Mann–Whitney test) within each dataset.