Regulation of ion homeostasis under salt stress.
When under salt stress, plants maintain a high concentration of K(+) and a low concentration of Na(+) in the cytosol. They do this by regulating the expression and activity of K(+) and Na(+) transporters and of H(+) pumps that generate the driving force for transport. Although salt-stress sensors remain elusive, some of the intermediary signaling components have been identified. Evidence suggests that a protein kinase complex consisting of the myristoylated calcium-binding protein SOS3 and the serine/threonine protein kinase SOS2 is activated by a salt-stress-elicited calcium signal. The protein kinase complex then phosphorylates and activates various ion transporters, such as the plasma membrane Na(+)/H(+) antiporter SOS1.
Zhu
Jian Kang
JK
Department of Plant Sciences, University of Arizona, Tucson, Arizona 85721, USA. jkzhu@ag.arizona.edu
D000222:Adaptation, Physiological / Q000187:drug effects / Q000235:genetics* / Q000502:physiology; D006706:Homeostasis / Q000187:drug effects; D063245:Plant Development; D010944:Plants / Q000187:drug effects / Q000235:genetics*; D011188:Potassium / Q000378:metabolism* / Q000494:pharmacology; D015398:Signal Transduction / Q000187:drug effects; D012964:Sodium / Q000378:metabolism* / Q000494:pharmacology
D012964:Sodium; D011188:Potassium