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Insights from an erroneous kinetochore-microtubule attachment state.

ABSTRACT: Faithful distribution of the genome requires that sister kinetochores, which assemble on each chromatid during cell division, interact with dynamic microtubules from opposite spindle poles in a configuration called chromosome biorientation. Biorientation produces tension that increases the affinity of kinetochores for microtubules via ill-defined mechanisms. Non-bioriented kinetochore-microtubule (kt-MT) interactions are prevalent but short-lived due to an error correction pathway that reduces the affinity of kinetochores for microtubules. Interestingly, incorrect kt-MT interactions can be stabilized by experimentally applying force to misoriented chromosomes. Here, a live-cell force assay is utilized to characterize the molecular composition of a common type of improper kt-MT attachment. Our force-related studies are also discussed in the context of current models for tension-dependent stabilization of kt-MT interactions.

SUBMITTER: Cane S

PROVIDER: S-EPMC3782542 | biostudies-literature | 2013 May-Jun

REPOSITORIES: biostudies-literature

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Insights from an erroneous kinetochore-microtubule attachment state.

Cane Stuart S McGilvray Philip T PT Maresca Thomas J TJ

Bioarchitecture 20130501 3

Faithful distribution of the genome requires that sister kinetochores, which assemble on each chromatid during cell division, interact with dynamic microtubules from opposite spindle poles in a configuration called chromosome biorientation. Biorientation produces tension that increases the affinity of kinetochores for microtubules via ill-defined mechanisms. Non-bioriented kinetochore-microtubule (kt-MT) interactions are prevalent but short-lived due to an error correction pathway that reduces t ...[more]

PMID: 23887229

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