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Sds22 regulates aurora B activity and microtubule-kinetochore interactions at mitosis.

ABSTRACT: We have studied Sds22, a conserved regulator of protein phosphatase 1 (PP1) activity, and determined its role in modulating the activity of aurora B kinase and kinetochore-microtubule interactions. Sds22 is required for proper progression through mitosis and localization of PP1 to mitotic kinetochores. Depletion of Sds22 increases aurora B T-loop phosphorylation and the rate of recovery from monastrol arrest. Phospho-aurora B accumulates at kinetochores in Sds22-depleted cells juxtaposed to critical kinetochore substrates. Sds22 modulates sister kinetochore distance and the interaction between Hec1 and the microtubule lattice and, thus, the activation of the spindle assembly checkpoint. These results demonstrate that Sds22 specifically defines PP1 function and localization in mitosis. Sds22 regulates PP1 targeting to the kinetochore, accumulation of phospho-aurora B, and force generation at the kinetochore-microtubule interface.

SUBMITTER: Posch M

PROVIDER: S-EPMC2953433 | biostudies-literature | 2010 Oct

REPOSITORIES: biostudies-literature

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Sds22 regulates aurora B activity and microtubule-kinetochore interactions at mitosis.

Posch Markus M Khoudoli Guennadi A GA Swift Sam S King Emma M EM Deluca Jennifer G JG Swedlow Jason R JR

The Journal of cell biology 20101001 1

We have studied Sds22, a conserved regulator of protein phosphatase 1 (PP1) activity, and determined its role in modulating the activity of aurora B kinase and kinetochore-microtubule interactions. Sds22 is required for proper progression through mitosis and localization of PP1 to mitotic kinetochores. Depletion of Sds22 increases aurora B T-loop phosphorylation and the rate of recovery from monastrol arrest. Phospho-aurora B accumulates at kinetochores in Sds22-depleted cells juxtaposed to crit ...[more]

PMID: 20921135

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Sds22 regulates aurora B activity and microtubule–kinetochore interactions at mitosis

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