The stress-activated Hog1 kinase is a selective transcriptional elongation factor for genes responding to osmotic stress.
Regulation of gene expression by stress-activated protein kinases (SAPKs) is essential for cell adaptation to extracellular stimuli. Exposure of yeast to high osmolarity results in activation of the SAPK Hog1, which associates with transcription factors bound at target promoters and stimulates transcriptional initiation. Unexpectedly, activated Hog1 also associates with elongating Pol II and components of the elongation complex. Hog1 is selectively recruited to the entire coding region of osmotic stress genes, but not to constitutively expressed genes. Selective association of Hog1 with the transcribed region of osmoresponsive genes is determined by the 3' untranslated region (3' UTR). Lastly, Hog1 is important for the amount of the RNA polymerase II (Pol II) elongation complex and of mRNA produced from genes containing osmoresponsive coding regions. Thus, in addition to its various functions during transcriptional initiation, Hog1 behaves as a transcriptional elongation factor that is selective for genes induced upon osmotic stress.
Proft
Markus
M
Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts 02115, USA.
Mas
Glòria
G
de Nadal
Eulàlia
E
Vendrell
Alexandre
A
Noriega
Núria
N
Struhl
Kevin
K
Posas
Francesc
F
D020413:3' Untranslated Regions / Q000378:metabolism; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism; D015966:Gene Expression Regulation, Fungal; D020928:Mitogen-Activated Protein Kinases / Q000235:genetics* / Q000378:metabolism; D008954:Models, Biological; D009997:Osmotic Pressure; D012319:RNA Polymerase II / Q000378:metabolism; D012333:RNA, Messenger / Q000096:biosynthesis; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000502:physiology*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics* / Q000378:metabolism; D035602:Transcriptional Elongation Factors / Q000235:genetics* / Q000378:metabolism
D020413:3' Untranslated Regions; D005656:Fungal Proteins; D012333:RNA, Messenger; D029701:Saccharomyces cerevisiae Proteins; D035602:Transcriptional Elongation Factors; C088589:HOG1 protein, S cerevisiae; D020928:Mitogen-Activated Protein Kinases; D012319:RNA Polymerase II; C511736:RPB1 protein, S cerevisiae