Nuclear envelope assembly and disassembly.

Abstract

The nuclear envelope (NE) is a highly complex dynamic structure that must provide a boundary separating the cytoplasm from the nucleoplasm during inter-phase but not during mitosis, when chromosomes are segregated between two daughter cells. In other words, the nuclear envelope must be stable during interphase but unstable during mitosis. Understanding the processes that control nuclear envelope breakdown (NEBD) and reassembly has been the subject of intensive research during the past eight years, such that over the last year or two a consensus has started to emerge that was put succinctly by John Newport at the 1992 Lancaster symposium of the Society of Experimental Biology, when he expressed the view that NEBD and reassembly are extremes of a dynamic process involving continuous structural rearrangements of the components of the envelope. In this chapter we will review what is currently known about this process and propose a general model for the regulation of the major events involved.