Dynamic Signaling in the Hog1 MAPK Pathway Relies on High Basal Signal Transduction

作者：Macia Javier; Regot Sergi; Peeters Tom; Conde Nuria; Sole Ricard^*; Posas Francesc

来源：Science Signaling, 2009, 2(63): ra13.

DOI：10.1126/scisignal.2000056

Appropriate regulation of the Hog1 mitogen-activated protein kinase (MAPK) pathway is essential for cells to survive osmotic stress. Here, we show that the two sensing mechanisms upstream of Hog1 display different signaling properties. The Sho1 branch is an inducible nonbasal system, whereas the Sln1 branch shows high basal signaling that is restricted by a MAPK-mediated feedback mechanism. A two-dimensional mathematical model of the Snl1 branch, including high basal signaling and a Hog1-regulated negative feedback, shows that a system with basal signaling exhibits higher efficiency, with faster response times and higher sensitivity to variations in external signals, than would systems without basal signaling. Analysis of two other yeast MAPK pathways, the Fus3 and Kss1 signaling pathways, indicates that high intrinsic basal signaling may be a general property of MAPK pathways allowing rapid and sensitive responses to environmental changes.

• 出版日期2009-3-24