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Bora and the kinase Aurora a cooperatively activate the kinase Plk1 and control mitotic entry.

ABSTRACT: A central question in the study of cell proliferation is, what controls cell-cycle transitions? Although the accumulation of mitotic cyclins drives the transition from the G2 phase to the M phase in embryonic cells, the trigger for mitotic entry in somatic cells remains unknown. We report that the synergistic action of Bora and the kinase Aurora A (Aur-A) controls the G2-M transition. Bora accumulates in the G2 phase and promotes Aur-A-mediated activation of Polo-like kinase 1 (Plk1), leading to the activation of cyclin-dependent kinase 1 and mitotic entry. Mechanistically, Bora interacts with Plk1 and controls the accessibility of its activation loop for phosphorylation and activation by Aur-A. Thus, Bora and Aur-A control mitotic entry, which provides a mechanism for one of the most important yet ill-defined events in the cell cycle.

SUBMITTER: Seki A

PROVIDER: S-EPMC2834883 | biostudies-literature | 2008 Jun

REPOSITORIES: biostudies-literature

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Bora and the kinase Aurora a cooperatively activate the kinase Plk1 and control mitotic entry.

Seki Akiko A Coppinger Judith A JA Jang Chang-Young CY Yates John R JR Fang Guowei G

Science (New York, N.Y.) 20080601 5883

A central question in the study of cell proliferation is, what controls cell-cycle transitions? Although the accumulation of mitotic cyclins drives the transition from the G2 phase to the M phase in embryonic cells, the trigger for mitotic entry in somatic cells remains unknown. We report that the synergistic action of Bora and the kinase Aurora A (Aur-A) controls the G2-M transition. Bora accumulates in the G2 phase and promotes Aur-A-mediated activation of Polo-like kinase 1 (Plk1), leading to ...[more]

PMID: 18566290

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