F. Distribution of cluster sizes in HEK293 cells transfected with STIM1-mCherry (black, n = 2644) or STIM1A-mCherry (red, n = 4754) at 0.2 µm2 intervals in %. G. Violin blot of the cluster shown in (F), shown as median, first and third quartile. ns: not significant with Mann Whitney test. D 