Movie 3

Counter-balancing of actomyosin ring contraction by impulsive force.
The center of an epithelial cell in the Lifeact-GFP–overexpressing embryo was directly irradiated with a single pulse of the femtosecond laser (15 nJ/pulse) at time = 0 s. After formation of the actomyosin ring at around 120 s, impulsive forces generated by femtosecond laser (25 nJ/pulse) were loaded onto the center of the actomyosin ring 50 times at 1 s intervals (red dots in 138–187 s). Scale bar: 10 μm.