Targeting of PP2C in Budding Yeast

  • Irene M. Ota
  • James Mapes
Part of the Methods in Molecular Biology book series (MIMB, volume 365)


Type 2C Ser/Thr phosphatases or PP2Cs are monomeric metal-requiring protein phosphatases that are present in prokaryotes and eukaryotes. In the yeast Saccharomyces cerevisiae, there are seven PP2Cs called PTCs (phosphatase 2C). Molecular genetic studies have implicated PTCs in many different functions, including RNA splicing, the unfolded protein response, mitogen-activated protein kinase (MAPK) pathway, and cell-cycle regulation. We have shown that three PTCs (Ptc1, Ptc2, and Ptc3), regulate the stress-activated high-osmolarity glycerol (HOG) mitogen-activated protein kinase (MAPK) pathway. Proteomics studies have provided additional possible functions for these phosphatases by identifying interacting proteins. These studies have also provided the possible means by which these phosphatases are targeted to their substrates. For example, Nbp2-Ptc1 was identified as an interacting pair in yeast two-hybrid studies, and Nbp2 was found together with Ptc1 and HOG pathway kinases. We have shown that Nbp2 is an adapter in this pathway, mediating interaction between Ptc1 and the Pbs2 MAP/ERK kinase in the HOG pathway.

Key Words

PP2C Ptc1 Nbp2 adapter MAPK MEK budding yeast 


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Copyright information

© Humana Press Inc. 2007

Authors and Affiliations

  • Irene M. Ota
    • 1
  • James Mapes
    • 2
  1. 1.Huntsman Cancer InstituteUniversity of UtahSalt Lake CityUSA
  2. 2.Department of Molecular, Cellular, and Developmental BiologyUniversity of ColoradoBoulderUSA

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