Loss of cell partitions and multinucleation in famk-1Δ embryos. (A) Arrest stage of famk-1Δ embryos that failed to hatch. (B) Images of control and famk-1Δ embryos expressing fluorescent probes that label the plasma membrane and chromatin. Arrows indicate multinucleated cells. Scale bar, 5 µm. The graph on the right shows frequency of embryos with at least one clear multinucleation event at different embryonic stages. (C) High-time-resolution images of famk-1Δ embryos. Arrowheads point to partition loss that results in multinucleation; the two classes of events associated with multinucleation and their relative frequency are shown. Scale bars, 10 µm.