Fusion Pore Diameter Regulation by Cations Modulating Local Membrane Anisotropy

Figure 4

The relationship between the equilibrium radius of the pore (𝑅_eq) and the relative cation concentration in the vesicle (𝑛⁺/𝑛^+max). The relationship between 𝑛⁺/𝑛^+max and 𝑅_eq is derived from the minimization of the membrane bending energy. Note that an increase in the cation concentration (bold line) leads to an abrupt increase in the fusion pore radius, 𝑅_eq (i.e., the opening of the fusion pore), while, in the opposite direction (dotted line), a reduction in the cation concentration leads to an abrupt closure of the fusion pore.