Fig. 3. Dependence of the energy barrier and the acceleration factor of the fusion pore formation on the spontaneous curvature of the proximal monolayers and on the tilt decay length.

a, b describe the effects of varying background spontaneous curvature, $J_{\mathrm{S}}^0$ on the energy barrier (a) and the acceleration factor (b): Blue line $J_{\mathrm{S}}^0=-0.02{\mathrm{nm}}^{-1}$, red line $J_{\mathrm{S}}^0=-0.058{\mathrm{nm}}^{-1}$, and green line $J_{\mathrm{S}}^0=-0.1{\mathrm{nm}}^{-1}$. c, d describe the effect of tilt decay length, $l$ on the energy barrier (c) and the acceleration factor (d): Blue line $l=1\mathrm{nm}$, red line $l=1.5\mathrm{nm}$, and green line $l=2\mathrm{nm}$. The parameter values used in all panels: $x^{*}=6.6\mathrm{nm}$, $R_{\mathrm{B}}=15\mathrm{nm}$, ${\kappa }_{\mathrm{m}}=10k_{\mathrm{b}}$T, ${\overline{\kappa }}_{\mathrm{m}}=-5k_{\mathrm{b}}T$, and $\lambda =10\mathrm{pN}$. The tilt decay length size used in a and in b is $l=1.5\mathrm{nm}$ and the background spontaneous curvature in panels c and d is $J_{\mathrm{S}}^0=-0.1{\mathrm{nm}}^{-1}$. In panels b and d the acceleration factor is indicated for the maximal calculated area fraction of LPC in the proximal monolayers. b: Blue line, $J_{\mathrm{S}}^0=-0.02{\mathrm{nm}}^{-1}$, maximal fraction of LPC is 6%, $\beta =0.9$. Red line, $J_{\mathrm{S}}^0=-0.06{\mathrm{nm}}^{-1},$ maximal fraction of LPC is 6.8%, $\beta =1.6$. Green line, $J_{\mathrm{S}}^0=-0.1{\mathrm{nm}}^{-1},$ maximal fraction of LPC is 7.5% LPC, $\beta =4$. d: Blue line, $l=1\mathrm{nm},$ maximal fraction of LPC is 10%, β = 1.5 Red line, $l=1.5\mathrm{nm},$ maximal fraction of LPC is 7.5%, β = 4. Green line, l = 2 nm, maximal fraction of LPC is 7.5%, β = 46.