Debaryomyces hansenii, a highly osmo-tolerant and halo-tolerant yeast, maintains activated Dhog1p in the cytoplasm during its growth under severe osmotic stress.
The HOG pathway is an important mitogen-activated protein kinase (MAPK) signal transduction pathway in Saccharomyces cerevisiae that mediates adaptation of cells to hyper-osmotic stress. Activation of this pathway causes rapid but transient, phosphorylation of the MAPK Hog1p. Phosphorylated Hog1p is rapidly transported to the nucleus that results in the transcription of target genes. The HOG pathway appears to be ubiquitous in yeast. Components of HOG pathway have also been identified in Debaryomyces hansenii, a highly osmotolerant and halotolerant yeast. We have studied activation of HOG pathway in D. hansenii under different stress conditions. Our experiments demonstrated that the pathway is activated by high osmolarity, oxidative and UV stress but not by heat stress. We have provided evidence, for the first time, that D. hansenii maintains phosphorylated Dhog1p in the cytoplasm during its growth under severe osmotic stress.
Sharma
Pratima
P
Institute of Microbial Technology, Sector 39A, Chandigarh, 160036 India.
Meena
Netrapal
N
Aggarwal
Monika
M
Mondal
Alok K
AK
D003593:Cytoplasm / Q000378:metabolism; D005656:Fungal Proteins / Q000378:metabolism*; D008856:Microscopy, Fluorescence; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism*; D009997:Osmotic Pressure; D010766:Phosphorylation; D004718:Saccharomycetales / Q000201:enzymology / Q000378:metabolism*; D015398:Signal Transduction
D005656:Fungal Proteins; D020928:Mitogen-Activated Protein Kinases