Figure 4: Model predictions.
(A) Simulated and measured fraction of free KCs. The green dots are the experimental values for pairs (capture time of the first KC in a pair; mean ± s.e.m., n = 51). The black line shows simulations for the case with 6 MTs and the other parameters given in Fig. 3C and the corresponding standard error of the mean. All simulation results are averaged over 10000 runs with random initial orientations for both MTs and KC pairs. (B) Predictions of the model for the total KC capture time (or moment of the capture of the last KC) in the case where the three KC pairs were replaced by six free KCs. First bar: simulations with the measured parameters (Fig. 3C); second bar: simulations for six unpaired KCs; third bar: simulations for six pairs of KCs. The parameters that were changed with respect to the measured values are given under each bar. Note that DKC = 2.9·10−2 μm2/min was obtained by measuring the diffusion coefficient of KCs that were unpaired, i.e., their motion was not correlated with that of any other KC. The green area marks the experimental values (mean ± s.e.m.). The capture time for a pair of KC was computed as the time needed to capture the first KC in that pair. (C) The effect of diffusion on the average time of KC capture (mean first passage time averaged over each KC). The simulations were performed using the measured parameters (first bar); DMT = 0, DKC = 0 (second bar); DKC = 0 (third bar); DMT = 0 (fourth bar), as shown schematically under each bar. All other parameters were the same as in Fig. 3C. All simulations are for 6 MTs. The green area marks the experimental values (mean ± s.e.m.). (D) Average capture time (mean first passage time averaged over each KC) as a function of MT length for the case in which dynamic instability is switched off (MT length is constant). All the other parameters are as in Fig. 3C. All simulations are for 6 MTs. The green area marks the experimental values (mean ± s.e.m.).
