Figure 7: Clustering dynamics in living cells.
(a) Representative data (open circles) and fits (curves) of the normalized intensity of fluorescent F-actin in cells during (a) clustering after Cytochalasin D treatment, (b) declustering after washing out Cytochalasin D and (c) normal conditions for untreated cells. For a,b, curves and data are shifted on the time axis by the time delay offset (see Methods) such that the fitted sigmoid is centred at t=0. The condition of the media was initially changed to Cytochalasin D or washed and replenished with growth media for a,b, respectively, at the first time point of each data set. Different colours represent different representative clusters or intracellular positions across multiple cells. Distributions of time constants for (d) clustering (average τC=28±5 s (s.e.m.), n=15 clusters) and (e) declustering (average τD=155±42 s (s.e.m.), n=12 clusters). Representative time evolution during cluster (f) formation and (g) disintegration inside live cells. In f,g, t=0 corresponds to the time when the drug is added or removed. Scale bars, 5 μm. Arrows point to the same cluster at different time points. Typical cells that are (h) untreated, (i) treated with Cytochalasin D for 1 h, and (j) treated with Latrunculin A for 1 h. Images in h–j are maximum projections from z-stacks with 1 μm z-resolution. Scale bars, 20 μm.
