※ Hisk family introduction

    Hisk can serve as a histidine kinase and act as a osmosensor at the plasma membrane. Phosphorylation of Sln1p inhibits the HOG1 MAP kinase osmosensing pathway via a phosphorelay mechanism including Ypd1p and the response regulator, Ssk1p. SLN1 also activates an MCM1-dependent reporter gene, P-lacZ, but this function is independent of Ssk1p. There are genetic and biochemical evidence showing that Skn7p is the response regulator for this alternative Sln1p signaling pathway. Skn7p-dependent oxidative-stress activation is also regulated by the SLN1 phosphorelay functions of Skn7p (1).

Reference
1. Li, S., Ault, A., Malone, C.L., Raitt, D., Dean, S., Johnston, L.H., Deschenes, R.J. and Fassler, J.S. (1998) The yeast histidine protein kinase, Sln1p, mediates phosphotransfer to two response regulators, Ssk1p and Skn7p. EMBO J, 17, 6952-6962