Glutamate triggers long-distance, calcium-based plant defense signaling

  title={Glutamate triggers long-distance, calcium-based plant defense signaling},
  author={Masatsugu Toyota and Dir Spencer and Satoe Sawai-Toyota and Wang Jiaqi and Tong Zhang and Abraham J Koo and Gregg A. Howe and Simon Gilroy},
  pages={1112 - 1115}
Rapid, long-distance signaling in plants A plant injured on one leaf by a nibbling insect can alert its other leaves to begin anticipatory defense responses. Working in the model plant Arabidopsis, Toyota et al. show that this systemic signal begins with the release of glutamate, which is perceived by glutamate receptor–like ion channels (see the Perspective by Muday and Brown-Harding). The ion channels then set off a cascade of changes in calcium ion concentration that propagate through the… 
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Noxious effects of cell surface display glutamate sensors on plant growth and development
Overall, data indicate sensor noxiousness was dependent on its membrane-tethering and likely caused by sequestration of extracellular glutamate, specifically at the cell surface, thereby either disrupting the supply of glutamate to meristematic cells and/or by impairing local glutamatergic signaling during development.


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Regardless of how signals move from cell to cell, they help prepare distant parts of the plant for impending challenges from specific biotic or abiotic stresses.
Salt stress-induced Ca2+ waves are associated with rapid, long-distance root-to-shoot signaling in plants
Plants possess a rapid stress signaling system based on Ca2+ waves that propagate through the plant at rates of up to ∼400 µm/s, and this system likely elicits systemic molecular responses in target organs and may contribute to whole-plant stress tolerance.
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