Stress-induced map kinase Hog1 is part of transcription activation complexes.
In response to hyperosmotic environments, most eukaryotic cells activate a specialized mitogen-activated protein (MAP) kinase pathway. In S. cerevisiae, the key protein kinase, Hog1, coordinates the transcriptional induction of a variety of genes devoted to osmoadaptation and general stress protection. Depending on the promoter context, Hog1 can function through a variety of structurally unrelated transcription factors. Using chromatin precipitation assays, we discovered that the kinase itself becomes intimately linked with promoter regions during stress responses. This interaction is dependent on the presence of stress-mediating transcriptional activators. In turn, Hog1 modulates promoter association of at least one of these factors. Additional findings highlight the possibility that Hog1 constitutes an integral part of the upstream activation complex, perhaps targeting not only the activator but also components of the general transcription machinery.
Alepuz
P M
PM
Department of Biochemistry and Molecular Cell Biology, Ludwig Boltzmann-Forschungsstelle, University of Vienna, Dr. Bohrgasse 9, A1030 Vienna, Austria.
Jovanovic
A
A
Reiser
V
V
Ammerer
G
G
D002374:Catalase / Q000235:genetics / Q000378:metabolism; D002467:Cell Nucleus / Q000201:enzymology; D002843:Chromatin / Q000235:genetics / Q000378:metabolism; D015966:Gene Expression Regulation, Fungal; D005993:Glycerolphosphate Dehydrogenase / Q000235:genetics / Q000378:metabolism; D006360:Heat-Shock Proteins / Q000235:genetics / Q000378:metabolism; D007716:Kluyveromyces; D020928:Mitogen-Activated Protein Kinases / Q000235:genetics* / Q000378:metabolism; D009004:Monosaccharide Transport Proteins / Q000235:genetics / Q000378:metabolism; D009997:Osmotic Pressure; D010766:Phosphorylation; D011401:Promoter Regions, Genetic / Q000502:physiology; D029701:Saccharomyces cerevisiae Proteins; D012568:Schizosaccharomyces; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism; D015533:Transcriptional Activation / Q000235:genetics*
D002843:Chromatin; C120535:HOT1 protein, S cerevisiae; C112591:HSP12 protein, S cerevisiae; D006360:Heat-Shock Proteins; D009004:Monosaccharide Transport Proteins; D029701:Saccharomyces cerevisiae Proteins; D014157:Transcription Factors; D005993:Glycerolphosphate Dehydrogenase; D002374:Catalase; C088589:HOG1 protein, S cerevisiae; D020928:Mitogen-Activated Protein Kinases