10.1371/journal.pcbi.1005386.g002 Vinal Lakhani Vinal Lakhani Timothy C. Elston Timothy C. Elston Receptor Occupancy at Equilibrium. Public Library of Science 2017 novel simulation methods multicellular organisms gradient yeast cells filter fluctuations Unicellular organisms use gradient chemical gradients Particle-Based Reaction-Diffusion model 2017-02-16 21:03:48 Figure https://plos.figshare.com/articles/figure/Receptor_Occupancy_at_Equilibrium_/4663579 <p><b>(A)</b> Simulation results for the number of active receptors as a function of time. Each color represents a different realization of the process. The thick, solid, black line is the mean from the data (5035 Ste2*). The thin, solid, black lines represent one standard deviation away from the mean, as calculated from the data (±52 Ste2*). The thick, dashed, black line is the theoretical mean calculated from <a href="http://www.ploscompbiol.org/article/info:doi/10.1371/journal.pcbi.1005386#pcbi.1005386.e003" target="_blank">Eq 1a</a> (5027 Ste2*). The thin, dashed, black lines are one theoretical standard deviation from the mean as calculated from <a href="http://www.ploscompbiol.org/article/info:doi/10.1371/journal.pcbi.1005386#pcbi.1005386.e004" target="_blank">Eq 1b</a> (±50 Ste2*). <b>(B)</b> A histogram of the data in <b>(A)</b>. The vertical lines are equivalent to those in <b>(A)</b>. The red curve shows the theoretical distribution. <b>(C)</b> A plot of time-averaged receptor occupancy. Each time point displays the average occupancy of the preceding 10 minutes. No average is available for t < 10min. The black lines are similar to those in <b>(A)</b>. The simulation mean is 5034 ± 23 Ste2*, and the theoretical mean is 5027 ± 19 Ste2*. The theoretical mean is again calculated with <a href="http://www.ploscompbiol.org/article/info:doi/10.1371/journal.pcbi.1005386#pcbi.1005386.e003" target="_blank">Eq 1a</a>, but the time-averaged standard deviation is calculated from <a href="http://www.ploscompbiol.org/article/info:doi/10.1371/journal.pcbi.1005386#pcbi.1005386.e013" target="_blank">Eq 5</a> and the relation described in the text. <b>(D)</b> A histogram of the data in <b>(C)</b>. The time-averaged distribution is much narrower (σ = 23 Ste2*) than the instantaneous distribution (σ = 52 Ste2*). The parameters used for these simulations are reported in <b><a href="http://www.ploscompbiol.org/article/info:doi/10.1371/journal.pcbi.1005386#pcbi.1005386.t001" target="_blank">Table 1</a></b>, with binding and unbinding rates of 1.6×10<sup>6</sup> (M·s)<sup>-1</sup> and 0.011 s<sup>-1</sup>, respectively, and no ligand gradient.</p>