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Kip3, the yeast kinesin-8, is required for clustering of kinetochores at metaphase.

ABSTRACT: In Saccharomyces cerevisiae, chromosome congression clusters kinetochores on either side of the spindle equator at metaphase. Many organisms require one or more kinesin-8 molecular motors to achieve chromosome alignment. The yeast kinesin-8, Kip3, has been well studied in vitro but a role in chromosome congression has not been reported. We investigated Kip3's role in this process using semi-automated, quantitative fluorescence microscopy and time-lapse imaging and found that Kip3 is required for congression. Deletion of KIP3 increases inter-kinetochore distances and increases the variability in the position of sister kinetochores along the spindle axis during metaphase. Kip3 does not regulate spindle length and is not required for kinetochore-microtubule attachment. Instead, Kip3 clusters kinetochores on the metaphase spindle by tightly regulating kinetochore microtubule lengths.

SUBMITTER: Wargacki MM

PROVIDER: S-EPMC2976798 | biostudies-literature | 2010 Jul

REPOSITORIES: biostudies-literature

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Kip3, the yeast kinesin-8, is required for clustering of kinetochores at metaphase.

Wargacki Megan M MM Tay Jessica C JC Muller Eric G EG Asbury Charles L CL Davis Trisha N TN

Cell cycle (Georgetown, Tex.) 20100701 13

In Saccharomyces cerevisiae, chromosome congression clusters kinetochores on either side of the spindle equator at metaphase. Many organisms require one or more kinesin-8 molecular motors to achieve chromosome alignment. The yeast kinesin-8, Kip3, has been well studied in vitro but a role in chromosome congression has not been reported. We investigated Kip3's role in this process using semi-automated, quantitative fluorescence microscopy and time-lapse imaging and found that Kip3 is required for ...[more]

PMID: 20603597

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