Time-lapse DIC microscopy air-1 RNAi in the one-cell stage of C. elegans embryos. Time-lapse movies were acquired using Differential Interference Contrast (DIC) microscopy (Axioskop, Carl Zeiss Inc.) at 1 frame every 5 seconds, and played at 20 frames/sec. Note the presence of uniform contractility in air-1 (RNAi) in contrast to the wild-type embryo (Movie 1).