The role of plasma membrane H⁺‐ATPase in jasmonate‐induced ion fluxes and stomatal closure in Arabidopsis thaliana

Abstract

SUMMARYMethyl jasmonate (MeJA) elicits stomatal closure in many plant species. Stomatal closure is accompanied by large ion fluxes across the plasma membrane (PM

Stomatal Defense a Decade Later

“…In particular, methylated JA (MeJA) has been used extensively to elucidate JA-dependent responses. Although some studies have provided evidence that MeJA closes the stomatal pore (Suhita et al, 2004;Munemasa et al, 2007;DesclosTheveniau et al, 2012;Hua et al, 2012;Yan et al, 2015), this could not be verified by other research groups (Speth et al, 2009;Savchenko et al, 2014). This inconsistency might be explained by the fact that an endogenous ABA threshold is needed for MeJA-induced stomatal closure (Hossain et al, 2011).…”

Contrasting nutrient–disease relationships: Potassium gradients in barley leaves have opposite effects on two fungal pathogens with different sensitivities to jasmonic acid

“…Furthermore, the allocation of K and Ca into individual cell types (Fricke, Hinde, Leigh, & Tomos, ) could change under K starvation, which again might differentially affect pathogens with specific invasion patterns. With reported effects of JA on ion fluxes being taken into account (Evans, Gottlieb, & Bach, ; Yan et al, ), it is also possible that an initial rise in JA leads to redistribution of K and/or Ca between cellular compartments and cell types. Monitoring ion concentrations and pathogen development at a much higher spatial resolution would be a good way forward to test these hypotheses.…”

“…To visualize the leaf profiles of potentially relevant parameters, we assigned a semiquantitative score between −−− (much lower than the median) and +++ (much higher than the median) to the measured absolute values, and we plotted this score against the leaf zones for both K-replete and K-deprived plants. As can be seen in Figure 7, R. commune (Evans, Gottlieb, & Bach, 2003;Yan et al, 2015), it is also possible that an initial rise in JA leads to redistribution of K and/or Ca between cellular compartments and cell types. Monitoring ion concentrations and pathogen development at a much higher spatial resolution would be a good way forward to test these hypotheses.…”

Herbivore exposure alters ion fluxes and improves salt tolerance in a desert shrub

“…NMT (Yan, McLamore, et al, ) uses computer‐controlled stepper motors to oscillate an ion‐selective microelectrode near the surface of tissues, providing real‐time measurements of ion transmembrane flux (McLamore & Porterfield, ). The ion flux is calculated on the basis of Fick's law of diffusion, J 0 = ﹣ D ·( dc / dx ), where J 0 represents the ion flux (in units of pmol·cm −2 ·s −1 ), dc / dx is the ion concentration gradient, and D is the ion diffusion constant (in cm −2 ·sec −1 ) in a particular medium (Sun, Li, Yin, Shangguan, & Xu, ).…”

“…The ion flux is calculated on the basis of Fick's law of diffusion, J 0 = ﹣ D ·( dc / dx ), where J 0 represents the ion flux (in units of pmol·cm −2 ·s −1 ), dc / dx is the ion concentration gradient, and D is the ion diffusion constant (in cm −2 ·sec −1 ) in a particular medium (Sun, Li, Yin, Shangguan, & Xu, ). Net K + , Na + , H + , and Ca 2+ fluxes during plant response to stresses were measured using an NMT system (NMT‐YG‐100; Younger USA LLC, Amherst, MA, USA; Sun, Chen, et al, ; Sun, Dai, et al, ; Yan, Luo, et al, ; Yan, McLamore, et al, ; Zhang et al, ). Prepulled silanized glass micropipettes (diameter = 4–5 μm, XY‐DJ‐01; Xuyue [Beijing] Science and Technology Co. Ltd., Beijing, China) were prepared and calibrated as described below.…”