An osmosensing signal transduction pathway in yeast.
Yeast genes were isolated that are required for restoring the osmotic gradient across the cell membrane in response to increased external osmolarity. Two of these genes, HOG1 and PBS2, encode members of the mitogen-activated protein kinase (MAP kinase) and MAP kinase kinase gene families, respectively. MAP kinases are activated by extracellular ligands such as growth factors and function as intermediate kinases in protein phosphorylation cascades. A rapid, PBS2-dependent tyrosine phosphorylation of HOG1 protein occurred in response to increases in extracellular osmolarity. These data define a signal transduction pathway that is activated by changes in the osmolarity of the extracellular environment.
Brewster
J L
JL
Department of Biochemistry and Cell Biology, Rice University, Houston, TX 77251.
de Valoir
T
T
Dwyer
N D
ND
Winter
E
E
Gustin
M C
MC
D000595:Amino Acid Sequence; D015152:Blotting, Northern; D017871:Calcium-Calmodulin-Dependent Protein Kinases; D005800:Genes, Fungal; D008969:Molecular Sequence Data; D009994:Osmolar Concentration; D010766:Phosphorylation; D010769:Phosphothreonine / Q000378:metabolism; D019000:Phosphotyrosine; D011494:Protein Kinases / Q000737:chemistry / Q000235:genetics*; D015183:Restriction Mapping; D012441:Saccharomyces cerevisiae / Q000235:genetics*; D015398:Signal Transduction / Q000235:genetics*; D014443:Tyrosine / Q000031:analogs & derivatives / Q000378:metabolism; D014882:Water-Electrolyte Balance / Q000235:genetics*
D010769:Phosphothreonine; D019000:Phosphotyrosine; D014443:Tyrosine; D011494:Protein Kinases; D017871:Calcium-Calmodulin-Dependent Protein Kinases