Energy landscape for dome-shaped assemblies.

(A) Total energy of the system as a function of the attachment angle θ, for different values of the membrane–protein adhesion strength |W|. For |W| = |W|as ≃ 0.25 mN/m, the energy landscape has a minimum at θ = 0°. As |W| increases beyond this value, the attachment angle θ of the minimum energy state (i.e. the optimal attachment angle) moves continuously towards higher θ-values, reaching θ = 75° (corresponding to neck closure and scission) for |W| = |W|sc ≃ 0.56 mN/m. (B) Optimal attachment angle θ as a function of |W|. In both (A) and (B), the total area of the bud is nm2, corresponding to a final bud radius Rbu ≃ 42 nm.