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Elm1 kinase activates the spindle position checkpoint kinase Kin4.

ABSTRACT: Budding yeast asymmetric cell division relies upon the precise coordination of spindle orientation and cell cycle progression. The spindle position checkpoint (SPOC) is a surveillance mechanism that prevents cells with misoriented spindles from exiting mitosis. The cortical kinase Kin4 acts near the top of this network. How Kin4 kinase activity is regulated and maintained in respect to spindle positional cues remains to be established. Here, we show that the bud neck-associated kinase Elm1 participates in Kin4 activation and SPOC signaling by phosphorylating a conserved residue within the activation loop of Kin4. Blocking Elm1 function abolishes Kin4 kinase activity in vivo and eliminates the SPOC response to spindle misalignment. These findings establish a novel function for Elm1 in the coordination of spindle positioning with cell cycle progression via its control of Kin4.

SUBMITTER: Caydasi AK

PROVIDER: S-EPMC3101594 | biostudies-literature | 2010 Sep

REPOSITORIES: biostudies-literature

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Elm1 kinase activates the spindle position checkpoint kinase Kin4.

Caydasi Ayse Koca AK Kurtulmus Bahtiyar B Orrico Maria I L MI Hofmann Astrid A Ibrahim Bashar B Pereira Gislene G

The Journal of cell biology 20100901 6

Budding yeast asymmetric cell division relies upon the precise coordination of spindle orientation and cell cycle progression. The spindle position checkpoint (SPOC) is a surveillance mechanism that prevents cells with misoriented spindles from exiting mitosis. The cortical kinase Kin4 acts near the top of this network. How Kin4 kinase activity is regulated and maintained in respect to spindle positional cues remains to be established. Here, we show that the bud neck-associated kinase Elm1 parti ...[more]

PMID: 20855503

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