Fig. 3.

Tilt, energy potential, and equilibrium force with which a PF pushes as a function of the ring's size. (A) Tilting angle χ for the three terminal dimers as a function of w. (B) Energy for lateral bonds engaged in force production as a function of w (only the last two dimers are shown). Symbols α and β refer to the tubulin subunits. With increasing w, every bond gets stretched, but the changes are smaller for less distal dimers. (C) Equilibrium pushing force exerted by a bending PF for different values of w.