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Dynamic microtubules are essential for efficient chromosome capture and biorientation in S. cerevisiae.

ABSTRACT: Attachment of chromosomes to the mitotic spindle has been proposed to require dynamic microtubules that randomly search three-dimensional space and become stabilized upon capture by kinetochores. In this study, we test this model by examining chromosome capture in Saccharomyces cerevisiae mutants with attenuated microtubule dynamics. Although viable, these cells are slow to progress through mitosis. Preanaphase cells contain a high proportion of chromosomes that are attached to only one spindle pole and missegregate in the absence of the spindle assembly checkpoint. Measurement of the rates of chromosome capture and biorientation demonstrate that both are severely decreased in the mutants. These results provide direct evidence that dynamic microtubules are critical for efficient chromosome capture and biorientation and support the hypothesis that microtubule search and capture plays a central role in assembly of the mitotic spindle.

SUBMITTER: Huang B

PROVIDER: S-EPMC2064488 | biostudies-literature | 2006 Oct

REPOSITORIES: biostudies-literature

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Dynamic microtubules are essential for efficient chromosome capture and biorientation in S. cerevisiae.

Huang Baoying B Huffaker Tim C TC

The Journal of cell biology 20061001 1

Attachment of chromosomes to the mitotic spindle has been proposed to require dynamic microtubules that randomly search three-dimensional space and become stabilized upon capture by kinetochores. In this study, we test this model by examining chromosome capture in Saccharomyces cerevisiae mutants with attenuated microtubule dynamics. Although viable, these cells are slow to progress through mitosis. Preanaphase cells contain a high proportion of chromosomes that are attached to only one spindle ...[more]

PMID: 17030980

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