Nuclear envelope proteins and their role in nuclear positioning and replication.

Controlled movement of the nucleus is important in a wide variety of plant cellular events. Positioning involving intact nuclei occurs in cell division, development, tip growing systems such as the root hair and in response to stimuli, including light, touch and infection. Positioning is also essential in the division and replication of nuclear components, ranging from chromosome attachment to the breakdown and reformation of the nuclear envelope. Although description and understanding of the processes involved have advanced rapidly in recent years, significant gaps remain in our knowledge, especially concerning nuclear proteins involved in anchoring and interacting with cytoskeletal and nucleoskeletal elements involved in movement. In the present review, processes involving the movement and positioning of nuclei and nuclear components are described together with novel proteins implicated in nucleoskeletal and cytoskeletal interactions.