Salt and drought stress signal transduction in plants.
Salt and drought stress signal transduction consists of ionic and osmotic homeostasis signaling pathways, detoxification (i.e., damage control and repair) response pathways, and pathways for growth regulation. The ionic aspect of salt stress is signaled via the SOS pathway where a calcium-responsive SOS3-SOS2 protein kinase complex controls the expression and activity of ion transporters such as SOS1. Osmotic stress activates several protein kinases including mitogen-activated kinases, which may mediate osmotic homeostasis and/or detoxification responses. A number of phospholipid systems are activated by osmotic stress, generating a diverse array of messenger molecules, some of which may function upstream of the osmotic stress-activated protein kinases. Abscisic acid biosynthesis is regulated by osmotic stress at multiple steps. Both ABA-dependent and -independent osmotic stress signaling first modify constitutively expressed transcription factors, leading to the expression of early response transcriptional activators, which then activate downstream stress tolerance effector genes.
Zhu
Jian-Kang
JK
Department of Plant Sciences, University of Arizona, Tucson, Arizona 85721, USA. jkzhu@ag.arizona.edu
D000040:Abscisic Acid / Q000096:biosynthesis / Q000502:physiology; D006706:Homeostasis; D009997:Osmotic Pressure; D010944:Plants / Q000378:metabolism*; D011494:Protein Kinases / Q000378:metabolism; D015398:Signal Transduction; D012965:Sodium Chloride; D014867:Water
D014867:Water; D012965:Sodium Chloride; D000040:Abscisic Acid; D011494:Protein Kinases