Figure 5. Lower lattice coverage or slower diffusion does not dramatically change the mean first-passage time (MFPT).

(A) First-passage time at different lattice coverages (67% and 33%). Closed circles are cases where Gag-Pol dimerization occurs in 100% of trajectories, while open circles are cases where Gag-Pol dimerization occurs in <100%. The gray line is the first-passage time when two free Gag-Pols diffusing on an empty spherical surface bind to one another. For the weakest lattice, rebinding is actually faster than diffusional encounter times between a dilute pair. (B) MFPT at different diffusion constants of the lipid. A monomer of Gag on the membrane diffuses at 0.2 µm²/s (black data), and diffuses slower as it grows in size consistent with Einstein-Stokes (Methods). We also simulated the system where diffusion of all species was slowed by a factor of 10 (red data). The MFPT is also not sensitive to changes in the dimer strength (Figure 5—figure supplement 1).

Figure 5—figure supplement 1. Effect of dimer interaction strength of mean first-passage time (MFPT) is minimal for these physiologic values.

Black data are from simulations with a dimer free energy of –11.62k_BT, and red data are more stable at –13.62k_BT. Unlike the effect of changing the hexamer free energy, as evidenced by the x-axis, a more stable dimer interaction has minimal effect on the MFPT. Filled data are from models where all trajectories produced dimerization events, open circles are lower bounds as not all trajectories produced events over the simulation time.