Mitotic kinases and phosphatases cooperate to shape the right response.
Ontology highlight
ABSTRACT:
SUBMITTER: Vallardi G
PROVIDER: S-EPMC4614840 | biostudies-other | 2015
REPOSITORIES: biostudies-other
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Project description:Temporal control over protein phosphorylation and dephosphorylation is crucial for accurate chromosome segregation and for completion of the cell division cycle during exit from mitosis. In budding yeast, the Cdc14 phosphatase is thought to be a major regulator at this time, while in higher eukaryotes PP2A phosphatases take a dominant role. Here, we use time-resolved phosphoproteome analysis in budding yeast to evaluate the respective contributions of Cdc14 and the two main PP2A isoforms, PP2A(Cdc55) and PP2A(Rts1). This reveals an overlapping requirement for all three phosphatases during mitotic progression. Cdc14 instructs the sequential pattern of phosphorylation changes, in part through its preferential recognition of serine-based cyclin-dependent kinase (Cdk) substrates. PP2A(Cdc55) and PP2A(Rts1) in turn exhibit a broad substrate spectrum with some selectivity for phospho-threonines and a role for PP2A(Rts1) in sustaining Aurora kinase activity. Our results illustrate synergy and coordination between phosphatases as they orchestrate phosphoproteome dynamics during mitotic progression.
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