TOR controls transcriptional and translational programs via Sap-Sit4 protein phosphatase signaling effectors
| Autor: | Susan G. Campbell, N. Shane Cutler, Maria E. Cardenas, John R. Rohde, Sara A. Zurita-Martinez, Mark P. Ashe |
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| Rok vydání: | 2004 |
| Předmět: |
Saccharomyces cerevisiae Proteins
Transcription Genetic Saccharomyces cerevisiae Phosphatase Protein Serine-Threonine Kinases Phosphatidylinositol 3-Kinases Genes Reporter Eukaryotic initiation factor Phosphoprotein Phosphatases Protein Phosphatase 2 Molecular Biology Cell Growth and Development Adaptor Proteins Signal Transducing biology Translation (biology) Cell Biology Protein phosphatase 2 Ribonucleoprotein U2 Small Nuclear biology.organism_classification Phosphoproteins TOR signaling Phosphotransferases (Alcohol Group Acceptor) Biochemistry Gene Expression Regulation Protein Biosynthesis TOR Serine-Threonine Kinases Signal transduction Protein Kinases Signal Transduction |
| Zdroj: | Molecular and cellular biology. 24(19) |
| ISSN: | 0270-7306 |
| Popis: | The Tor kinases are the targets of the immunosuppressive drug rapamycin and couple nutrient availability to cell growth. In the budding yeast Saccharomyces cerevisiae, the PP2A-related phosphatase Sit4 together with its regulatory subunit Tap42 mediates several Tor signaling events. Sit4 interacts with other potential regulatory proteins known as the Saps. Deletion of the SAP or SIT4 genes confers increased sensitivity to rapamycin and defects in expression of subsets of Tor-regulated genes. Sap155, Sap185, or Sap190 can restore these responses. Strains lacking Sap185 and Sap190 are hypersensitive to rapamycin, and this sensitivity is Gcn2 dependent and correlated with a defect in translation, constitutive eukaryotic initiation factor 2alpha hyperphosphorylation, induction of GCN4 translation, and hypersensitivity to amino acid starvation. We conclude that Tor signals via Sap-Sit4 complexes to control both transcriptional and translational programs that couple cell growth to amino acid availability. |
| Databáze: | OpenAIRE |
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