Appendix 1—figure 3. Additional properties of single fusion pores in the presence of full-length Syt1 or soluble C2AB.

Open-pore conductance fluctuations relative to mean (A), average flicker rate during a burst (B), average open-pore probability, $P_o$, during a current burst (fraction of time pore is in the open state during a burst) (C), and average burst lifetime, $T_o$, (D) for the indicated conditions. (E) Distributions of the number of flickers per burst, $N_{flickers}$, for the indicated conditions. Fits to geometric distributions are shown in red, $y=p{\left(1-p\right)}^{n-1},n=1,2,3,\dots$. Best fit parameters (with ± 95% confidence intervals) are $p=0.072(0.053,0.092)$ (no Syt1, 100 μM Ca²⁺, averaged over 49 individual fusion pores from 10 cells, mean $N_{flickers}=12.8$), 0.083(0.051,0115) (Syt1, 0 μM Ca²⁺; averaged over 24 individual fusion pores from 11 cells, mean $N_{flickers}=11.0$), 0.053(0.044,0.063) (Syt1, 100 μM Ca²⁺; averaged over 123 individual fusion pores from 20 cells, mean $N_{flickers}=17.7$). (F) Distribution of burst lifetimes, $T_o$ for the indicated conditions. Best fits to single exponentials are shown as red curves, with means (and 95% confidence intervals) as follows. No Syt1, 100 μM Ca²⁺: 6.1 s (4.7 to 8.3 s, 49 fusion pores from 10 cells), Syt1, 0 μM Ca²⁺: 6.5 s (4.5 to 10.1 s, 24 fusion pores from 11 cells), Syt1, 100 μM Ca²⁺: 16 s (13.5 to 19.3 s, 123 fusion pores from 20 cells). In A-D, the two-sample Kolmogorov-Smirnov test was used to assess significant differences between the "no C2AB" group and the rest. *, **, *** indicate p<0.05, 0.01, and 0.001, respectively. Comparison between Syt1 and C2AB in the presence of Ca²⁺ and PI(4,5)P₂ are also indicated (using the two-sample Kolmogorov-Smirnov test).