Fig. 3: Possible mechanisms of MT lattice destabilization by GTP hydrolysis.

a Visualization of the starting configuration of an MT in the tubulin dilution simulations. GDP-bound tubulin dimers are shown with light and dark green spheres. GTP-bound dimers are shown with yellow and orange spheres. b Dependence of MT length on time in three independent repeats of the tubulin dilution simulation: PF bending stiffness is identical for GTP- and GDP-bound PFs and equal to 174 kcal mol⁻¹ rad⁻²; lateral bond strength, b_lat equals 8 and 4.7 kcal mol⁻¹ for GTP- and GDP-bound tubulins, respectively. Blue arrow indicates a brief pause of rapid GDP-MT lattice disassembly at a random GTP-tubulin remnant, which happened occasionally in some simulation runs (also see Supplementary Movie 3). c Dependence of the total number of remaining GTP-tubulin subunits on time in three independent repeats of tubulin dilution simulation from panel b. d Dependence of MT length on time in two independent repeats of tubulin dilution simulation: the lateral bond strength is set to 4.7 kcal mol⁻¹, regardless of the bound nucleotide; PF bending stiffnesses are 78 and 174 kcal mol⁻¹ rad⁻² for GTP- and GDP-bound PFs, respectively. e Dependence of the total number of remaining GTP-tubulin subunits on time in two independent repeats of tubulin dilution simulation from panel d.