Fig. 3.

Mechanics of the Piezo dome. Force exerted on the Piezo dome, $F_P$, for the observed Piezo dome radii of curvature, $R_P=R_{\text{obs}}$, obtained from (minus) the derivative of the stationary free membrane bending energy with respect to $R_P$, $F_P=-\frac{\partial G_M}{\partial R_P}$ in Eq. 2, at $R_P=R_{\text{obs}}$ for the measured Piezo vesicle radii $R_v$ in Fig. 2C. In mechanical equilibrium of the Piezo–membrane system, the restoring force generated internally by the Piezo dome is given by $-F_P$. The gray curve shows the force on the Piezo dome obtained by fitting the mean curvature force in Eq. 4, $F_P^{MC}\left(R_P\right)$, to the force–displacement values of the Piezo dome, $(R_P, F_P$), yielding $K_P=18\pm 2.1 k_{B}T$ and $R_0=42\pm 12 \text{nm}$ in Eqs. 3 and 4.