EDFigure 5. A single calcium spark occurs around an hour before cells divide.

(A) Blocking stretch-induced proliferation with gadolinium at two hours post-stretch does not affect the percentages of cells in S phase, as measured by EdU incorporation from the mean of six independent experiments, where error bars are s.e.m. and P values from a t-test compared to the non-stretched control show no significance. (B) Inhibition of Piezo1 with Gd³⁺ or transcription with alpha-amanitin blocks stretch-induced cytoplasmic cyclin B accumulation and mitosis (H3P), where each micrograph is representative of >100 samples except for alpha-amanitin (40 samples) and bar=10μm. (C) Quantification of time from calcium spark to cell rounding measured from 10 mitotic events in 8 videos. Error bars=s.e.m. (D) Sample graph measuring the time (minutes) from calcium spark (arrow) to cell rounding (arrowhead) in MDCK cells expressing the calcium indicator, CMV-R-GECO1 using Nikon Elements.