Taming the spindle for containing the chromosomes

Cell Cycle. 2005 Mar;4(3):376-9. doi: 10.4161/cc.4.3.1537. Epub 2005 Mar 17.


Checkpoint controls are critical for coordination of cell cycle events, especially during exposure to perturbations or stresses. The DNA replication checkpoint is activated in S phase in response to replication stresses that impede fork progression. Mec1 and Rad53 are critical effectors of this control pathway; they maintain the integrity of stalled replication forks and prevent premature segregation of unreplicated chromosomes. It has long been thought that the checkpoint inhibits precocious segregation of chromosomes by preventing early onset of mitosis. However, recent evidence suggests that the replication checkpoint thwarts untimely chromosome separation not by inhibiting mitotic entry but by directly regulating spindle dynamics. These findings raise a number of issues which may require a revisit to the well-trodden territories of cell cycle regulation.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Cdc20 Proteins
  • Cell Cycle
  • Cell Cycle Proteins / metabolism
  • Checkpoint Kinase 2
  • Chromosomes / ultrastructure*
  • DNA Replication
  • Gene Expression Regulation, Fungal
  • Intracellular Signaling Peptides and Proteins
  • Kinetochores / metabolism
  • Mad2 Proteins
  • Microtubules / metabolism
  • Mitosis
  • Models, Biological
  • Nuclear Proteins / metabolism
  • Protein-Serine-Threonine Kinases / metabolism
  • S Phase
  • Saccharomyces cerevisiae Proteins / metabolism
  • Saccharomycetales
  • Spindle Apparatus*


  • CDC20 protein, S cerevisiae
  • Cdc20 Proteins
  • Cell Cycle Proteins
  • Intracellular Signaling Peptides and Proteins
  • MAD2 protein, S cerevisiae
  • Mad2 Proteins
  • Nuclear Proteins
  • Saccharomyces cerevisiae Proteins
  • Checkpoint Kinase 2
  • MEC1 protein, S cerevisiae
  • Protein-Serine-Threonine Kinases
  • RAD53 protein, S cerevisiae