Coordinating postmitotic nuclear pore complex assembly with abscission timing.

Cells divide and accurately inherit genomic and cellular content through synchronized changes in cellular organization and chromosome dynamics. Although DNA segregation, nuclear reformation, and cytokinesis/abscission temporally overlap, little is known about how these distinct events are coordinated to ensure accurate cell division. Recently, we found that disruption of postmitotic nuclear pore complex assembly, an essential aspect of the newly forming nuclear envelope, triggers an Aurora B-dependent delay in abscission. This delay is further characterized by mislocalized, aberrantly active Aurora B in the cytoplasm of midbody-stage cells. These results support a model in which an Aurora B-mediated abscission checkpoint provides surveillance of nuclear pore complex formation to ensure that elements of nuclear architecture are fully formed before daughter cells are physically separated. Here we discuss the process of nuclear pore complex assembly, describe potential mechanisms that may explain how this process could be coordinated with abscission, and postulate why such a checkpoint mechanism may exist.