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Regulation of aurora B kinase by the lipid raft protein flotillin-1.

ABSTRACT: The lipid raft protein Flotillin-1 was previously shown to be required for cell proliferation. Here we show that it is critical for the maintenance of the levels of the mitotic regulator Aurora B. Knockdown of Flotillin-1 induced aberrant mitotic events similar to those produced by Aurora B depletion and led to a marked decline in Aurora B levels and activity. Transfection of wild-type full-length Flotillin-1 or forms directed to the nucleus increased Aurora B levels and activity. Flotillin-1 interacted with Aurora B directly through its SPFH domain in a complex distinct from the chromosomal passenger protein complex, and the two proteins co-purified in nuclear, non-raft fractions. These observations are the first evidence for a function of Flotillin-1 outside of lipid rafts and suggest its critical role in the maintenance of a pool of active Aurora B.

SUBMITTER: Gomez V

PROVIDER: S-EPMC2898292 | biostudies-literature | 2010 Jul

REPOSITORIES: biostudies-literature

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Regulation of aurora B kinase by the lipid raft protein flotillin-1.

Gómez Valentí V Sesé Marta M Santamaría Anna A Martínez Juan D JD Castellanos Elisabet E Soler Marta M Thomson Timothy M TM Paciucci Rosanna R

The Journal of biological chemistry 20100429 27

The lipid raft protein Flotillin-1 was previously shown to be required for cell proliferation. Here we show that it is critical for the maintenance of the levels of the mitotic regulator Aurora B. Knockdown of Flotillin-1 induced aberrant mitotic events similar to those produced by Aurora B depletion and led to a marked decline in Aurora B levels and activity. Transfection of wild-type full-length Flotillin-1 or forms directed to the nucleus increased Aurora B levels and activity. Flotillin-1 in ...[more]

PMID: 20430883

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