Formation of clusters containing actomyosin ring components in the absence of turnover. (A) Contraction of rings in cell ghosts incubated with 0.5 mM ATP. Arrow, clusters. (B) Different categories of rings in cell ghosts incubated with 0.5 mM ATP. Shown are representative images of each category after 50-min ATP incubation. 1, 70 rings; 2, 88 rings; 3, 33 rings; 4, 37 rings. (C) Formation of Rlc1 clusters in rings in cell ghosts incubated with 0.5 mM ATP. Arrows, clusters. (D) Quantification of the number of clusters as a function of ring perimeter (black dotted line; 53 rings), and quantification of the mean distance between clusters as a function of ring perimeter (blue dotted line; 50 rings). The ring perimeter quantitated is the initial ring perimeter after ATP addition. (E) Distribution of the distance between Rlc1 clusters (478 clusters). Red line, log-Gaussian fitted line to the distribution; R², fitting coefficient. All the distances between clusters are plotted in the scattered dot plot.