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The tetrameric kinesin Kif25 suppresses pre-mitotic centrosome separation to establish proper spindle orientation.

ABSTRACT: Microtubules tether centrosomes together during interphase. How this is accomplished and what benefit it provides to the cell is not known. We have identified a bipolar, minus-end-directed kinesin, Kif25, that suppresses centrosome separation. Kif25 is required to prevent premature centrosome separation during interphase. We show that premature centrosome separation leads to microtubule-dependent nuclear translocation, culminating in eccentric nuclear positioning that disrupts the cortical spindle positioning machinery. The activity of Kif25 during interphase is required to maintain a centred nucleus to ensure the spindle is stably oriented at the onset of mitosis.

SUBMITTER: Decarreau J

PROVIDER: S-EPMC5376238 | biostudies-literature | 2017 Apr

REPOSITORIES: biostudies-literature

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The tetrameric kinesin Kif25 suppresses pre-mitotic centrosome separation to establish proper spindle orientation.

Decarreau Justin J Wagenbach Michael M Lynch Eric E Halpern Aaron R AR Vaughan Joshua C JC Kollman Justin J Wordeman Linda L

Nature cell biology 20170306 4

Microtubules tether centrosomes together during interphase. How this is accomplished and what benefit it provides to the cell is not known. We have identified a bipolar, minus-end-directed kinesin, Kif25, that suppresses centrosome separation. Kif25 is required to prevent premature centrosome separation during interphase. We show that premature centrosome separation leads to microtubule-dependent nuclear translocation, culminating in eccentric nuclear positioning that disrupts the cortical spind ...[more]

PMID: 28263957

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