Dataset Information

A specific protein-protein interaction accounts for the in vivo substrate selectivity of Ptp3 towards the Fus3 MAP kinase.

ABSTRACT: The mitogen-activated protein kinases (MAPKs) play critical roles in many signal transduction processes. Several MAPKs have been found in Saccharomyces cerevisiae, including Fus3 in the mating pathway and Hog1 in the osmotic-stress response pathway. Cells lacking Fus3 or Hog1 activity are deficient in mating or adaptation to osmotic shock, respectively. However, constitutive activation of either Fus3 or Hog1 is lethal. Therefore, yeast cells have to tightly regulate both the activation and inactivation of Fus3 and Hog1 MAPKs, which are controlled mainly by phosphorylation and dephosphorylation. Previous studies have shown that Fus3 activity is negatively regulated by protein tyrosine phosphatase Ptp3. In contrast, the Hog1 MAPK is mainly dephosphorylated by Ptp2 even though the two phosphatases share a high degree of sequence similarity. To understand the mechanisms of MAPK regulation, we examined the molecular basis underlying the in vivo substrate specificity between phosphatases and MAPKs. We observed that the amino-terminal noncatalytic domain of Ptp3 directly interacts with Fus3 via CH2 (Cdc25 homology) domain conserved among yeast PTPases and mammalian MAP kinase phosphatases and is responsible for the in vivo substrate selectivity of the phosphatase. Interaction between Ptp3 and Fus3 is required for dephosphorylation and inactivation of Fus3 under physiological conditions. Mutations in either Ptp3 or Fus3 that abolish this interaction cause a dysregulation of the Fus3 MAPK. Our data demonstrate that the specificity of MAP kinase inactivation in vivo by phosphatases is determined by specific protein-protein interactions outside of the phosphatase catalytic domain.

SUBMITTER: Zhan XL

PROVIDER: S-EPMC317133 | biostudies-literature | 1999 Nov

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

A specific protein-protein interaction accounts for the in vivo substrate selectivity of Ptp3 towards the Fus3 MAP kinase.

Zhan X L XL Guan K L KL

Genes & development 19991101 21

The mitogen-activated protein kinases (MAPKs) play critical roles in many signal transduction processes. Several MAPKs have been found in Saccharomyces cerevisiae, including Fus3 in the mating pathway and Hog1 in the osmotic-stress response pathway. Cells lacking Fus3 or Hog1 activity are deficient in mating or adaptation to osmotic shock, respectively. However, constitutive activation of either Fus3 or Hog1 is lethal. Therefore, yeast cells have to tightly regulate both the activation and inact ...[more]

PMID: 10557209

Similar Datasets

Project description:Despite their importance, plant MAP kinase targets are still poorly elucidated. Here, the specific in vivo interaction of an ethylene response factor (ERF104) with the Arabidopsis MAP kinase, MPK6, is shown by fluorescence resonance energy transfer. The interaction, which is lost within minutes after treatment with the flagellin-derived flg22 peptide, is dependent on both MPK6 kinase activity and rapid ethylene signaling initiated downstream of MPK6 activation. ERF104 is an MPK6 substrate and phosphorylation site mutations affected its stability. ERF104 activates promoters with GCC elements. This was evident from microarray data of overexpressing transgenic plants, where promoters of up regulated genes contain GCC motifs and chromatin immunoprecipitation showing ERF104 association with PDF1.2 promoter. The ERF104 overexpressor did not affect biotrophic bacteria proliferation but was more susceptible to necrotrophic Botrytis cinerea. Microarray performed with erf104 or mpk6 revealed only a limited number of flg22-induced genes that require these elements - possibly as a; result of functional redundancies. Thus, ERF104 phosphorylation by MPK6, in concert with ethylene signaling induced by pathogen-derived molecules, modulates defense in Arabidopsis. Experiment Overall Design: Leaves of six week old Col-0, erf104, mpk6 and 35S::ERF104 plants were infiltrated with 1ÂµM Flg22 or water and harvested four hours later. Total RNA was isolated and processed according to the Affymetrix protocol for biotin-labelled cRNA and hybridized to the Affymetrix ATH1 chip. The data Experiment Overall Design: was analyzed with Genespring GX 7.3.1 software (Agilent) with the following parameters: Filter on Flags for present or marginal in 50% of all considered experiments, Filter for reliable differentially expressed genes based on volcano plot (one way ANOVA p-value <0.05 and >3-fold change in expression). For the flg22 experiments, analysis for each genotype was separately performed and a composite list of flg22-regulated genes compiled â with the aim of including genes that may be differentially regulated in the genotype. Global expression profile was visualized by k-means clustering and condition tree (Genespring).

Dataset Information

A specific protein-protein interaction accounts for the in vivo substrate selectivity of Ptp3 towards the Fus3 MAP kinase.

Publications

A specific protein-protein interaction accounts for the in vivo substrate selectivity of Ptp3 towards the Fus3 MAP kinase.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets