Plasmalemma Abscisic Acid Perception Leads to RAB18 Expression via Phospholipase D Activation in Arabidopsis Suspension Cells
AUTOR(ES)
Hallouin, Matthieu
FONTE
American Society of Plant Physiologists
RESUMO
Abscisic acid (ABA) plays a key role in the control of stomatal aperture by regulating ion channel activities and water exchanges across the plasma membrane of guard cells. Changes in cytoplasmic calcium content and activation of anion and outward-rectifying K+ channels are among the earliest cellular responses to ABA in guard cells. In Arabidopsis suspension cells, we have demonstrated that outer plasmalemma perception of ABA triggered similar early events. Furthermore, a Ca2+ influx and the activation of anion channels are part of the ABA-signaling pathway leading to the specific expression of RAB18. Here, we determine whether phospholipases are involved in ABA-induced RAB18 expression. Phospholipase C is not implicated in this ABA pathway. Using a transphosphatidylation reaction, we show that ABA plasmalemma perception results in a transient stimulation of phospholipase D (PLD) activity, which is necessary for RAB18 expression. Further experiments showed that PLD activation was unlikely to be regulated by heterotrimeric G proteins. We also observed that ABA-dependent stimulation of PLD was necessary for the activation of plasma anion current. However, when ABA activation of plasma anion channels was inhibited, the ABA-dependent activation of PLD was unchanged. Thus, we conclude that in Arabidopsis suspension cells, ABA stimulation of PLD acts upstream from anion channels in the transduction pathway leading to RAB18 expression.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=166559Documentos Relacionados
- Alterations in Water Status, Endogenous Abscisic Acid Content, and Expression of rab18 Gene during the Development of Freezing Tolerance in Arabidopsis thaliana.
- Role of Abscisic Acid in Drought-Induced Freezing Tolerance, Cold Acclimation, and Accumulation of LT178 and RAB18 Proteins in Arabidopsis thaliana.
- Abscisic acid signal transduction in guard cells is mediated by phospholipase D activity
- Plasma Membrane Depolarization Induced by Abscisic Acid in Arabidopsis Suspension Cells Involves Reduction of Proton Pumping in Addition to Anion Channel Activation, Which Are Both Ca2+ Dependent
- Antisense suppression of phospholipase D alpha retards abscisic acid- and ethylene-promoted senescence of postharvest Arabidopsis leaves.