The HOG pathway controls osmotic regulation of transcription via the stress response element (STRE) of the Saccharomyces cerevisiae CTT1 gene

• Published in: The EMBO journal 1994-09, Vol.13 (18), p.4382-4389
• Main Authors: Schüller, C., Brewster, J.L., Alexander, M.R., Gustin, M.C., Ruis, H.
• Format: Article
• Language: English
• Subjects: Action of physical and chemical agents; Adaptation, Physiological; Biological and medical sciences; Calcium-Calmodulin-Dependent Protein Kinases - metabolism; Catalase - biosynthesis; Catalase - genetics; Cyclic AMP-Dependent Protein Kinases - metabolism; Fundamental and applied biological sciences. Psychology; Gene Expression Regulation, Fungal; Genes, Fungal - genetics; Microbiology; Mitogen-Activated Protein Kinase Kinases; Mitogen-Activated Protein Kinases; Molecular Sequence Data; Mycology; Osmotic Pressure; Phosphotyrosine; Protein Kinases - metabolism; Regulatory Sequences, Nucleic Acid - genetics; RNA, Messenger - biosynthesis; Saccharomyces cerevisiae; Saccharomyces cerevisiae - physiology; Saccharomyces cerevisiae Proteins; Signal Transduction; Transcription, Genetic; Tyrosine - analogs & derivatives; Tyrosine - analysis
• ISSN: 0261-4189; 1460-2075
• DOI: 10.1002/j.1460-2075.1994.tb06758.x

The HOG signal pathway of the yeast Saccharomyces cerevisiae is defined by the PBS2 and HOG1 genes encoding members of the MAP kinase kinase and of the MAP kinase family, respectively. Mutations in this pathway (deletions of PBS2 or HOG1, or point mutations in HOG1) almost completely abolish the induction of transcription by osmotic stress that is mediated by stress response elements (STREs). We have demonstrated previously that STREs also mediate induction of transcription by heat shock, nitrogen starvation and oxidative stress. This study shows that they are also activated by low external pH, sorbate, benzoate or ethanol stress. Induction by these other stress signals appears to be HOG pathway independent. HOG1‐dependent osmotic induction of transcription of the CTT1 gene encoding the cytosolic catalase T occurs in the presence of a protein synthesis inhibitor and can be detected rapidly after an increase of tyrosine phosphorylation of Hog1p triggered by high osmolarity. Consistent with a role of STREs in the induction of stress resistance, a number of other stress protein genes (e.g. HSP104) are regulated like CTT1. Furthermore, catalase T was shown to be important for viability under severe osmotic stress, and heat shock was demonstrated to provide cross‐protection against osmotic stress.