Syncytial stage embryos expressing a fusion protein of histone 2A and green fluorescent protein (His-GFP) were used to visualize chromatin in living embryos. A representative example of the syncytial, synchronous, nuclear divisions, progressing through mitosis with normal morphology and timing is shown. Decondensed DNA in interphase nuclei (A) began to condense as nuclei progressed into prophase (B). The condensed chromatin aligned along the mitotic spindle in metaphase (C). Normal metaphase persisted 2–3 min (C and D), followed by the separation and segregation of the DNA masses during anaphase (D). Finally, the chromatin decondenses in late telophase (E), and the cycle began again. The arrows indicate a single nucleus followed through mitosis (total length ∼8 min) The scale bar in E corresponds to 10 μm.