Breaking down the wall: the nuclear envelope during mitosis.

A defining feature of eukaryotic cells is the nucleus, which houses the genome inside the nuclear envelope (NE): a double lipid bilayer that separates the nuclear and cytoplasmic materials. Although the NE is commonly viewed as a barrier that is overcome only by embedded nuclear pore complexes (NPCs) that facilitate nuclear-cytoplasmic trafficking, recent work in a wide range of eukaryotes reveals that the NE is a dynamic organelle that is modified each time the cell divides to ultimately establish two functional daughter nuclei. Here, we review how studies of divergent mitotic strategies have helped elucidate common properties of NE biology that allow it to function throughout the cell cycle.