Stomatal closure induced by phytosphingosine-1-phosphate and sphingosine-1-phosphate depends on nitric oxide and pH of guard cells in Pisum sativum

Abstract

Phyto-S1P and S1P induced stomatal closure in epidermis of pea ( Pisum sativum ) by raising the levels of NO and pH in guard cells. Phosphosphingolipids, such as phytosphingosine-1-phosphate (phyto-S1P) and sphingosine-1-phosphate (S1P), are important signaling components during drought stress. The biosynthesis of phyto-S1P or S1P is mediated by sphingosine kinases (SPHKs). Although phyto-S1P and S1P are known to be signaling components in higher plants, their ability to induce stomatal closure has been ambiguous. We evaluated in detail the effects of phyto-S1P, S1P and SPHK inhibitors on signaling events leading to stomatal closure in the epidermis of Pisum sativum. Phyto-S1P or S1P induced stomatal closure, along with a marked rise in nitric oxide (NO) and cytoplasmic pH of guard cells, as in case of ABA. Two SPHK inhibitors, DL-threo dihydrosphingosine and N',N'-dimethylsphingosine, restricted ABA-induced stomatal closure and prevented the increase of NO or pH by ABA. Modulators of NO or pH impaired both stomatal closure and increase in NO or pH by phyto-S1P/S1P. The stomatal closure by phyto-S1P/S1P was mediated by phospholipase D and phosphatidic acid (PA). When present, PA elevated the levels of pH, but not NO of guard cells. Our results demonstrate that stomatal closure induced by phyto-S1P and S1P depends on rise in pH as well as NO of guard cells. A scheme of signaling events initiated by phyto-S1P/S1P, and converging to cause stomatal closure, is proposed.

Glucosylhydroxyceramides Modulate Secretion Machinery of a Subset of Plasmodesmata Proteins and a Change in the Callose Accumulation

“…In plant, the sphingolipid metabolite S1P involves in guard cell signal transduction (Ng et al, 2001; Coursol et al, 2003; Coursol et al, 2005; Worrall et al, 2008; Puli et al, 2016). S1P in guard triggers alteration in nitric oxide (NO), cytoplasmic calcium and cytoplasmic pH (Ng et al, 2001; Puli et al, 2016). Reactive oxygen species and cytoplasmic calcium are well known trigger of callose accumulation, probably through posttranslational regulation of callose synthases (Xu et al, 2017; Wu et al, 2018).…”

Characterization of tissue specific expressed proteins and metabolites in Cenchrus polystachion (L.) Schult and their role in apomixis

“…Sphingosine and 3-O-Sulfogalactosylceramide were upregulated among all other metabolites in both pollen (5.2) folds and seed (1.82) folds. Sphingosine and sphingosine 1 phosphate (S1P) regulation is interrelated and increased levels of sphingosine can bring about direct intracellular responses by increasing the cytosolic calcium concentration (Ca2+) which was also reported in Pisum sativum [42]. Phytosphingosine play import role in calcium mediated stomatal closure resulting in lesser rate of photosynthesis.…”

Effect of Sphingosine-1-Phosphate on Intracellular Free Ca2+ in Cat Esophageal Smooth Muscle Cells

“…Although some S1P-mediated responses are attributed to the action of an intracellular second messenger, most of the effects of S1P are thought to be receptor-mediated ( Nema et al ., 2016 ; Puli et al ., 2016 ; Ng et al ., 2017 ; Serafimidis et al ., 2017 ). The S1PR1-induced Rac1 activation was Ca 2+ dependent and that the increase in intracellular Ca 2+ was triggered by the action of PI–PLC and the IP3 receptor, it was suggested that the Ca 2+ was released from the store in the ER ( Li et al ., 2015 ).…”