Sister chromatid tension and the spindle assembly checkpoint.
The spindle assembly checkpoint (SAC) is a feedback control system that monitors the state of kinetochore/microtubule attachment during mitosis and halts cell cycle progression until all chromosomes are properly aligned at the metaphase plate. The state of chromosome-microtubule attachment is implicated as a crucial factor in the checkpoint response. On the contrary, lack of tension in the centromere-kinetochore region of sister chromatids has been shown to regulate a pathway of correction of undesired chromosome-microtubule connections, while the presence of tension is believed to promote the stabilization of attachments. We discuss how tension-sensitive phenomena, such as attachment correction and stabilization, relate to the SAC and we speculate on the existence of a single pathway linking error correction and SAC activation.
Department of Experimental Oncology, European Institute of Oncology, Milan, Italy.
Luigi
L
Nezi
Andrea
A
Musacchio
D000818:Animals; D064127:Aurora Kinases; D018797:Cell Cycle Proteins / Q000235:genetics / Q000378:metabolism; D002842:Chromatids / Q000378:metabolism*; D020090:Chromosome Segregation / Q000502:physiology; D006801:Humans; D018386:Kinetochores / Q000378:metabolism; D008870:Microtubules; D008938:Mitosis; D008954:Models, Biological; D017346:Protein Serine-Threonine Kinases / Q000235:genetics / Q000378:metabolism; D008941:Spindle Apparatus / Q000235:genetics / Q000378:metabolism*
D018797:Cell Cycle Proteins; D064127:Aurora Kinases; D017346:Protein Serine-Threonine Kinases