Movie 5.

Early cell nuclei labelling (using maternal expressed GFP) combined with late cell nuclei labelling (using zygotically expressed NLS-GFP). 2xPE-Gal4 is driving the expression of the NNT construct (with EGFP deposited maternally) together with NLSGFP construct to label the mesoderm (using the 5xUAS::NNT, UAS::NLS-GFP fly line). Time-lapse movie starts during cellularization at stage 5 (i.e. 40 min before furrow closure).