Fig. 7. Motions within dense phases of N130 + rpL5 show bimodality.

a MSD of the PD plotted against the lag time shows that N130 has super-diffusive and sub-diffusive regimes. Here, the abscissa is a unitless parameter t′ = t/t_D where t_D is the timescale over which the motion of the PD is purely diffusive. The red region in the panel indicates the timescales that fit best to purely diffusive motion. There is a timescale below t_D where the motion is super-diffusive and a timescale above t_D where the motion is sub-diffusive, with the regimes and corresponding exponents indicated in the panel. b Histograms of the exponents calculated for the mean square displacements of individual PDs. The bimodal distribution reflects the presence of super-diffusive and sub-diffusive regimes. Negative exponents result from uncertainty regarding the long-time behavior of the MSDs. c MSDs of the PD and charged residues in each of the acidic regions and the rpL5 peptides. In contrast to the PD, the acidic regions and the peptides show only sub-diffusive motions on all timescales. In all cases, averages were calculated over five replicates ($n=5$).