Nuclear size, nuclear pore number and cell cycle

Nucleus. Mar-Apr 2011;2(2):113-8. doi: 10.4161/nucl.2.2.15446.

Abstract

In eukaryotic cells, the nucleus is a complex and sophisticated organelle containing genomic DNA and supports essential cellular activities. Its surface contains many nuclear pore complexes (NPCs), channels for macromolecular transport between the cytoplasm and nucleus. It has been observed that the nuclear volume and the number of NPCs almost doubles during interphase in dividing cells, but the coordination of these events with the cell cycle was poorly understood, particularly in mammalian cells. Recently, we demonstrated that cyclin-dependent protein kinases (Cdks) control interphase NPC formation in dividing human cells. Cdks drive the very early step of NPC formation because Cdk inhibition suppressed the generation of "nascent pores," which are considered to be immature NPCs, and disturbed expression and localization of some nucleoporins. Cdk inhibition did not affect nuclear volume, suggesting that these two processes have distinct regulatory mechanisms in the cell cycle. The details of our experimental systems and finding are discussed in more depth. With new findings recently reported, we also discuss possible molecular mechanisms of interphase NPC formation.

Keywords: bio-imaging; cell-fusion; cyclin-dependent protein kinases (Cdks); nuclear pore complex (NPC); nuclear size.

MeSH terms

  • Animals
  • Cell Cycle* / drug effects
  • Cell Nucleus Size* / drug effects
  • Cricetinae
  • Cyclin-Dependent Kinases / antagonists & inhibitors
  • Cyclin-Dependent Kinases / metabolism
  • HeLa Cells
  • Humans
  • Interphase / drug effects
  • Mitosis / drug effects
  • Neoplasms / pathology
  • Nuclear Pore / drug effects
  • Nuclear Pore / metabolism*
  • Protein Kinase Inhibitors / pharmacology

Substances

  • Protein Kinase Inhibitors
  • Cyclin-Dependent Kinases