Probes) and analyzed by time-lapse spinning disk confocal microscopy (Andor Revolution). Frames were acquired every 5 seconds over the course of 15 minutes. After 5 minutes in vehicle (0.05% DMSO), 500 nM jasplakinolide was added. Scale bar is 10 mm. (MOV) Video S2 Region tracking analysis example. A. californica BCN injected with Alexa-568 actin (Molecular Probes) and analyzed by time-lapse spinning disk confocal microscopy (Andor Revolution). Tracked regions are outlined in red. The left panel shows tracking during vehicle pretreatment; the right panel shows tracking beginning 25 seconds after addition of 500 nM jasplaki- nolide. Images were acquired every 5 seconds for 5 minutes (vehicle) and 8 minutes 20 seconds (jasplakinolide). Scale bar is 5 mm. (MOV) Video S3 Actin dynamics during blebbistatin and blebbistatin/jasplakinolide treatment. A. californica BCN injected with Alexa-568 actin (Molecular Probes) and analyzed by References 1. 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