Movie 1.

Early cell nuclei labelling using NNT construct and 2xPE-Gal4 driver. 2xPE-Gal4 is driving the expression of the NNT construct with EGFP deposited maternally (left), or the NLS-GFP construct (right) to label the mesoderm. Time-lapse movies start during cellularization at stage 5 (25 min before furrow closure). In this and subsequent movies, the embryo was imaged from the ventral side, with anterior to the left.