Editors' ChoicePlant biology

Water Conservation Signal

STKE  03 Apr 2001:
Vol. 2001, Issue 76, pp. tw2
DOI: 10.1126/stke.2001.76.tw2

Sphingosine-1 phosphate (S1P) is a component of several signal transduction cascades in animal cells; however, a role for S1P in plants has been defined. Ng et al. first confirm that S1P is found in plant leaves and that drought conditions increase S1P levels. Treatment of leaves with S1P produces a dose-dependent decrease in stomatal pore aperture that is dependent on calcium. S1P treatment produced calcium oscillations in isolated guard cells, suggesting that S1P initiates a calcium signaling event that regulates stomatal pore closure. Abscisic acid is another signaling molecule that is regulated by calcium and that is involved in stomatal pore control. Treatment of leaves with an inhibitor of sphingosine kinase attenuated the decrease in stomatal pore aperture produced by abscisic acid, suggesting that the S1P signal and the abscisic acid signal converge to regulate water conservation pathways in plants.

C. K.-Y. Ng, K. Carr, M. R. McAinsh, B. Powell, A. M. Hetherington, Drought-induced guard cell signal transduction involves sphingosine-1-phosphate. Nature 410, 596-599 (2001). [Online Journal]