The yeast MAPK Hog1 is not essential for immediate survival under osmostress.
The yeast HOG pathway is activated in response to increased osmolarity and affects many cellular activities. As cells lacking Hog1 are osmo-sensitive it is believed that Hog1 is essential for survival under osmostress. We show, however, that hog1Delta cells survive and even proliferate to some degree under high osmostress for many hours. If forced to enter G1/G0 prior the exposure to osmostress, hog1Delta cells survive for at least 6days. We suggest that the primary role of Hog1 is not to preserve viability upon exposure to stress. We discuss the possibility that Hog1 is needed for proliferation under osmostress.
Maayan
Inbal
I
Department of Biological Chemistry, The Alexander Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem, Israel.
Engelberg
David
D
D002453:Cell Cycle; D049109:Cell Proliferation; D016193:G1 Phase; D005800:Genes, Fungal; D020935:MAP Kinase Signaling System; D020928:Mitogen-Activated Protein Kinases / Q000235:genetics / Q000378:metabolism*; D009154:Mutation; D009997:Osmotic Pressure; D012441:Saccharomyces cerevisiae / Q000166:cytology* / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism*
D029701:Saccharomyces cerevisiae Proteins; C088589:HOG1 protein, S cerevisiae; D020928:Mitogen-Activated Protein Kinases