Under low osmolarity conditions (click "Low Osmolarity"), the Sln1 kinase is active, and a phosphoryl group is transferred from Sln1 to Ypd1, and then to the Ssk1 and Skn7 response regulators. Phosphorylated Ssk1 cannot activate the Hog1 MAPK cascade, whereas aspartate phosphorylation stimulates gene expression by Skn7. In contrast, high osmolarity stress (click "High Osmolarity") inhibits the Sln1 kinase, and the unphosphorylated form of Ssk1 induces activation of the Hog1 cascade. Sln1 is shown as a monomer for simplicity, although dimerization may necessary for Sln1 activation (see text). H, histidine; A, aspartate; P, phosphate.
Citation: J. L. Santos, K. Shiozaki, Fungal Histidine Kinases. Science's STKE (2001), http://stke.sciencemag.org/cgi/content/full/OC_sigtrans;2001/98/re1.
This movie is in Macromedia Flash Player format. If you have difficulty viewing the movie, please consult the following information from Macromedia :