Regulation of transcription elongation in response to osmostress

Cells trigger massive changes in gene expression upon environmental fluctuations. The Hog1 stress-activated protein kinase (SAPK) is an important regulator of the transcriptional activation program that maximizes cell fitness when yeast cells are exposed to osmostress. Besides being associated with...

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Bibliographic Details
Authors: Silva, Andrea, Cavero, Santiago, Begley, Victoria, Solé, Carme, Böttcher, René, Chávez, Sebastián, Posas Garriga, Francesc, Nadal Clanchet, Eulàlia de
Format: article
Status:Published version
Publication Date:2017
Country:España
Institution:Universitat Pompeu Fabra
Repository:Repositorio Digital de la UPF
OAI Identifier:oai:repositori.upf.edu:10230/34223
Online Access:http://hdl.handle.net/10230/34223
http://dx.doi.org/10.1371/journal.pgen.1007090
Access Level:Open access
Keyword:Phosphorylation
Osmotic shock
Transcriptional control
Gene expression regulation
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Summary:Cells trigger massive changes in gene expression upon environmental fluctuations. The Hog1 stress-activated protein kinase (SAPK) is an important regulator of the transcriptional activation program that maximizes cell fitness when yeast cells are exposed to osmostress. Besides being associated with transcription factors bound at target promoters to stimulate transcriptional initiation, activated Hog1 behaves as a transcriptional elongation factor that is selective for stress-responsive genes. Here, we provide insights into how this signaling kinase functions in transcription elongation. Hog1 phosphorylates the Spt4 elongation factor at Thr42 and Ser43 and such phosphorylations are essential for the overall transcriptional response upon osmostress. The phosphorylation of Spt4 by Hog1 regulates RNA polymerase II processivity at stress-responsive genes, which is critical for cell survival under high osmostress conditions. Thus, the direct regulation of Spt4 upon environmental insults serves to stimulate RNA Pol II elongation efficiency.