Figure 4.

Dynamics of colocalization of four polymers in Model A. (a) Dynamics of the probability distribution of the different states is shown as function of time, t. Here molecule concentration, c, and binding affinity, E (c = 1.0% E = 4.4 kT), are chosen to have an equilibrium state where the state with two-polymer couples is the most likely (upper region in the phase diagram of Fig. 3b). Polymers are initially set in a random configuration, with no couples. After t ∼ 1 h, a first couple is formed. Later on, in the majority of cases, a second couple is assembled. (b) Average normalized energy of the system, ɛ, plotted as a function of time. (Squares) Same value of c and E used for the plot in panel a, with the first plateau corresponding to the formation of the first polymer couple, and the second, lower plateau to the formation of the second couple. (Diamonds) Dynamics when a below-threshold value of the energy is chosen: the system approaches the phase where no stable couples are formed and ɛ(t) reaches a comparatively higher plateau. Panels c and d show pictorial representations of two typical system configurations from Monte Carlo simulations in Model A in the region where two couples are formed (c), and in Model B where the four polymers come together (d); see text.