English: 1= cAMP signaling during aggregation without EGCG treatment. Spatio-temporal cAMP propagation were obtained by FRET signals of cAMP indicator Epac1-camps. FRET signal intensities are indicated as heat map (a snapshot is shown in Figure 7A). High concentration of cAMP is indicated by yellow and low concentration of cAMP is indicated by purple. Images were acquired every 30 seconds and the duration of the movie is 140 min. The field of view is 0.8 mm ×0.8 mm.