Figure 3.
Molecular Crowding Slows Down the Capture of New Molecules
(A) Examples of the distribution of 50 sites (red squares) in the absence of extra immobile obstacles at time point t = 0 (left) or among 200 obstacles (black circles) of size = 1 nm (center) or size = 10 nm (right). Obstacles occupy the position of other sites in the hexagonal grid and remain bound and immobile during all the simulation. Bar: 60 nm.
(B and C) Number of bound molecules in time in synapses (Pbind = 0.9) with initially 50 free sites, in absence of presence of 100 or 200 obstacles at t = 0, for small (B1-2) or large (C1-2) molecules. Distance between sites was 10 nm (B1 and C1) or 15 nm (B2 and C2). Obstacles had the same size than diffusing molecules. Colors as in B1. Mean (lines) ± SD (shaded areas) of 10 independent simulations.
Only the first 37.5s of the simulation are shown (the entire simulations are depicted in Figure S6).