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Comment
. 2010 Jul 13;107(28):12409-10.
doi: 10.1073/pnas.1006046107. Epub 2010 Jun 30.

Greatwall kinase protects mitotic phosphosites from barbarian phosphatases

Michael L Goldberg  1
Affiliations
Comment

Greatwall kinase protects mitotic phosphosites from barbarian phosphatases

Michael L Goldberg. Proc Natl Acad Sci U S A. .
No abstract available

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Conflict of interest statement

The author declares no conflict of interest.

Figures

Fig. 1.
Fig. 1.
Gwl kinase mediates the inactivation of PP2A/B55 phosphatase during M-phase entry. Green boxes indicate active enzymes; red boxes indicate inactive enzymes. MPF becomes activated through an autoregulatory process involving the removal of inhibitory phosphorylations from its CDK1 component. Active MPF then phosphorylates many targets, creating phosphoproteins involved in many downstream events in mitosis. Among the targets of MPF are enzymes (such as Cdc25 phosphatase, not shown) that participate in the autoregulatory loop and thus keep MPF activity high. MPF also phosphorylates and activates Gwl kinase. Gwl, in turn, inactivates (through a currently unknown mechanism) PP2A phosphatases with B55 regulatory subunits. If not inactivated by this Gwl-mediated process, PP2A/B55 phosphatases would prematurely reverse MPF-driven phosphorylations, preventing M-phase entry.
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References

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