Intrakinetochore stretch is associated with changes in kinetochore phosphorylation and spindle assembly checkpoint activity
Open Access
- 3 February 2009
- journal article
- Published by Rockefeller University Press in The Journal of cell biology
- Vol. 184 (3) , 373-381
- https://doi.org/10.1083/jcb.200808130
Abstract
Cells have evolved a signaling pathway called the spindle assembly checkpoint (SAC) to increase the fidelity of chromosome segregation by generating a “wait anaphase” signal until all chromosomes are properly aligned within the mitotic spindle. It has been proposed that tension generated by the stretch of the centromeric chromatin of bioriented chromosomes stabilizes kinetochore microtubule attachments and turns off SAC activity. Although biorientation clearly causes stretching of the centromeric chromatin, it is unclear whether the kinetochore is also stretched. To test whether intrakinetochore stretch occurs and is involved in SAC regulation, we developed a Drosophila melanogaster S2 cell line expressing centromere identifier–mCherry and Ndc80–green fluorescent protein to mark the inner and outer kinetochore domains, respectively. We observed stretching within kinetochores of bioriented chromosomes by monitoring both inter- and intrakinetochore distances in live cell assays. This intrakinetochore stretch is largely independent of a 30-fold variation in centromere stretch. Furthermore, loss of intrakinetochore stretch is associated with enhancement of 3F3/2 phosphorylation and SAC activation.Keywords
This publication has 22 references indexed in Scilit:
- Stable hZW10 kinetochore residency, mediated by hZwint-1 interaction, is essential for the mitotic checkpointThe Journal of cell biology, 2008
- Aurora B Kinase-Dependent Recruitment of hZW10 and hROD to Tensionless KinetochoresCurrent Biology, 2007
- Spindly, a novel protein essential for silencing the spindle assembly checkpoint, recruits dynein to the kinetochoreThe Journal of cell biology, 2007
- Kinetochore Dynein Is Required for Chromosome Motion and Congression Independent of the Spindle CheckpointCurrent Biology, 2007
- The outer plate in vertebrate kinetochores is a flexible network with multiple microtubule interactionsNature Cell Biology, 2007
- The spindle-assembly checkpoint in space and timeNature Reviews Molecular Cell Biology, 2007
- Spatial organization of a ubiquitous eukaryotic kinetochore protein network in Drosophila chromosomesChromosoma, 2007
- The spindle checkpoint: tension versus attachmentTrends in Cell Biology, 2005
- ZW10 links mitotic checkpoint signaling to the structural kinetochoreThe Journal of cell biology, 2005
- Differential expression of a phosphoepitope at the kinetochores of moving chromosomesThe Journal of cell biology, 1993